Another issue with the discourse coherence criterion is that we have no welldefined notion of "the same" cs-system between a producer and interpreter, at least not when the producer and interpreter are different people. We can ignore this problem or circumvent it by imagining that the interpreter and producer are the same person. This is the case for self-reflective grammaticality/acceptability intuitions that are often used in syntactic theory construction. However, in the more general situation where producer and interpreter are not the same person, the concept of discourse coherence requires further assumptions regarding similarity of cs-systems between different individuals.

# **6.2.3 Incremental organization in interpretation**

How does a stable configuration first arise in interpretation? In the canonical interpretation trajectory, sensory systems exert forces on c-systems and s-systems, which activate them and induce cs-resonances. The canonical trajectory makes the assumption that all cs-resonances were in an active, unexcited state before ϕ/e organization occurs, as in the trajectories below. But this oversimplification is obviously empirically inadequate. In most cases we expect some organization to arise before production of an utterance has finished.

To expand the empirical scope of our model of interpretation, incremental ϕ/e organization is necessary. However, the evolution of states during periods in which sensory systems activate cs-systems is generally unconstrained. Figure 6.9 contrasts two highly ordered, memory stack-like trajectories in which systems are incrementally e-organized. In the precedency mapping, each newly activated system becomes excited and occupies the first above-ground level, while previously excited systems are each promoted one level. If the interpreter enters a production regime, the interpretation-production mechanism behaves as a firstin first-out buffer, in a sense.

### 6 Grammaticality intuitions

Figure 6.8: Conceptual-syntactic systems are activated by perceptual systems.

Figure 6.9: Comparison of recency and precedency mappings in the e-organization of perceptually activated systems.

In the recency mapping, each newly excited system becomes the most highly excited system. In this case the relative excitations must be inverted before a production of the utterance could occur. This would suggest a new type of reorganization operator, Êinv. This inversion operation is somewhat problematic because it does not seem to occur in other circumstances; it is an ad hoc set of operations that is necessary to convert the recency-based organization to one which is consistent with production.

In any case, both precedency and recency incremental e-organization are probably too inflexible to be of much general use. Recall our depiction of the chaotic emergence of stable ϕ/e-configurations in production. We might expect something quite similar in interpretation: asymmetries in when individual sensory systems become active and exert forces on c- and s-systems, ambiguities in mappings from sensory systems to c- and s-systems, variation in the growth and competition timecourses of cs-resonances, inhomogeneity in the initial conditions, fluctuations in the surroundings – all of these make highly systematic organization scenarios such as those above quite unlikely.

A somewhat more realistic picture is one in which ϕ-configurations arise incrementally and exert a strong influence on subsequent e-organization. Meaning relations can form as cs-systems become active, and part of the stabilization process involves excitation of those systems. Hence we expect ϕ-configuration emergence to bias e-organization. For example, in the interpretation trajectory of *Bo knows Al drinks coffee* below, ϕ-configurations are organized as soon as the relevant cs-systems are active. In the subsequent examples, we show the most recently perceived system as grounded in the epoch prior to the one in which it becomes excited. Hence [knows]{V} is active in the epoch (e2), prior to participating in the configuration |Bo knows| in (e3). Likewise, [Al]{N} is active in (e3) and through a selective reorganization becomes excited in (e4). Incrementally organized states bias subsequent reorganizations. For example, the incrementally organized |Al drinks| state in epoch (e5) biases the system to reorganize to (e6), where |Al drinks coffee| is excited.

Figure 6.10: The immediate organization bias in incremental ϕ organization.

The excitation of [Bo][knows] in (e3) is hypothesized to result from an expectation that a newly active cs-system will enter into a ϕ-configuration with previously excited systems, without any intervening ϕ-configurations being organized. In our framework an "expectation" of this sort can be conceptualized as forces which promote coupling of a newly activated cs-system with an already activated or excited system. We refer to this as the *immediate organization bias*, and consider it to be the basis for incremental organization. Immediate organization explains why utterances such as *Al, Bo knows, drinks coffee* are more difficult to parse: the interpreter cannot couple [Bo]{N} with the previously activated/excited system, [Al]{N}.

### 6 Grammaticality intuitions

One empirically desirable consequence of incremental organization and the immediate organization bias is that a ϕ-configuration can prevent a newly excited system from participating in a stable configuration. To see why, consider the utterance in (12):

### (12) Al drinks coffee and tea is brewing.

This sentence is designed to create a garden path effect. The interpreter may initially understand *tea* as an object of *drinks*, because of the immediate organization bias. A possible interpretation trajectory is shown in Figure 6.11. (Note that the trajectory here and in examples to follow depict incremental e-organization, but this is not strictly necessary. The e-organization serves only to facilitate the depiction of the relevant ϕ-configurations). The garden path relational meaning experience of *drinks tea* corresponds to [tea]{−N} and [drinks]{V} being in a ϕconfiguration, shown in epoch (e3). However, [brew]{V} must −ϕ couple to a {−N} system in order to be coherent. Grounding of the |drinks tea| configuration prevents [brew]{V} and [tea]{−N} from being in a stable configuration. The inability of [tea]{−N} to couple to both [drinks]{V} and [brew]{V} is due to the selective reorganization from (e4) to (e5). The interpreter may then become aware of the non-coherence of the state in (e5). This awareness induces a grounding of all systems (e6) and reorganization to the state in (e7).

Figure 6.11: A garden path trajectory in which awareness of noncoherence induces grounding and reorganization.

On the other hand, the above utterance might not induce a garden path effect. The garden path arises because the selective reorganization Ê2 grounds only

### 6.2 Grammatical coherence

[coffee]{N}, as in Figure 6.12(A). Alternatively, if the selective reorganization Ê2 occurs as in (B), grounding |Al drinks coffee|, then [tea]{N} does not couple with [drinks]{V} and can couple with [brew]{V} in (e3).

Figure 6.12: A garden path occurs with the selective reorganization in (A) but not with the selective reorganization in (B).

The selective reorganization in (B) which grounds all of the cs-systems associated with |Al drinks coffee| would be more likely to occur in interpretation when the utterance is spoken slowly (or when a comma is present: *Al drinks coffee, and tea is brewing*), and less likely to occur when it is spoken quickly. Thus we can view prosodic manipulations such as boundary-lengthening as a mechanism for diminishing the forces which give rise to the immediate organization bias.

Our analysis of the garden path repair raises the question of how the interpreter, after becoming aware of the incoherence of the configuration in (e5), knows to reorganize so that [tea]{N} and [brew]{V} are coupled. This is an important, challenging question, which deserves future attention. In some circumstances, the interpreter does not – without assistance – achieve a coherent reorganization. This suggests that the |drink tea| system may not be sufficiently decoupled by grounding. The assistance, in everyday conversation, may be in the form of intonation (*Al drinks coffee, … and tea is brewing*). Indeed, even in the textbook example (*the horse raced past the barn fell*), some students who are unfamiliar with the example must be explicitly cued to evoke the relevant configuration (i.e. with *the horse that was raced…*) before they are able to achieve a coherent interpretation.

Garden path phenomena are a subset of a more general circumstance in which the system trajectory gets trapped in some subspace, preventing the trajectory from evolving to other possible states. In the prototypical garden path, the utterance is non-coherent when the system trajectory enters the trapping region,

### 6 Grammaticality intuitions

but more generally, the trapping subspace may be coherent and simply prevents some alternative, potentially coherent trajectory from occurring. This is why ambiguities can be difficult to notice. Consider the sentence in (13):

### (13) Al drinks soda coffee and tea are my favorites.

In interpretation of (13), immediate organization creates a strong bias for a |Al drinks soda| configuration to arise. This prevents the alternative coherent interpretation in which the producer means that *Al*, *drinks*, *soda*, *coffee*, and *tea* are their favorite things. The trapping substate here is a cs-resonance of [drinks] with {V}, which prevents a [drinks]{N} system from being excited. There are many circumstances in which garden path effects can arise (Ferreira 2005; Pritchett 1988), and comparisons of behavior in these should provide valuable information regarding incremental organization.

It should be noted here that the o/el conception does not gel with certain types of probabilistic models in which representations themselves are considered probabilistic (e.g. Chater & Manning 2006; Manning 2003). The system state is unarguably deterministic: there is one and only one state at any given moment of time, and so we should not reason that there are multiple parses of an utterance, each associated with a probability. Certainly, multiple configurations may be simultaneously active, to varying degrees, but this differs conceptually and implementationally from models in which a unity normalization is applied to construct a probability distribution over states.

Incremental e-organization is also relevant to understanding why "word salad" utterances such as those in (14) do not typically lead to coherence. In the marginal cases, intonation/punctuation can facilitate coherence when (in fixed order languages) the e-organization deviates from the typical ϕ-e mapping. We infer from these examples that incremental organization is influenced by learned ϕ-to-e mappings. What is important about this, from the perspective of our conceptual model, is that interpretation does not necessarily have access to ϕ relations. Interpreters may need to use e-to-ϕ mappings, which are inversions of learned ϕ-to-e mappings, in conjunction with immediate organization. Intonation/punctuation may diminish the influence of immediate organization on incremental organization.

	- b. \* Bo drinks Al knows coffee.
	- c. \* Coffee Bo Al drinks knows.
	- d. ? Al Bo knows drinks coffee. cf. Al Bo knows drinks coffee.

6.2 Grammatical coherence

e. ? Coffee Bo knows Al drinks. cf. Coffee – Bo knows – Al drinks. f. ? Bo Al drinks coffee knows. cf. ?Bo – Al drinks coffee – knows.

In (14)(a–c), there seems to be no amount of intonational/punctuational information which can make the highly abnormal mappings coherent. This suggests that, because of the immediate organization bias, substantial departures from learned ϕ-e mappings make achieving coherence more difficult. What constitutes a "substantial" departure is an open question.

# **6.2.4 Factors which influence coherence experiences**

It is important to view grammatical coherence as a phenomenon which is associated with an *experience*. More specifically, we experience a trajectory of relational meaning configurations which may or may not be stable. Although our generic hypothesis is that grammaticality/acceptability intuitions reflect these experiences, we have not considered which aspects of the trajectory our intuitions are sensitive to. A comprehensive study of intuitions should consider a wide variety of factors, e.g. the number of simultaneously excited ϕ-configurations, ϕ-configurations in which some systems are active but unexcited, activation of systems which cannot be immediately organized, interference from s-system differentiation, interference from c-system differentiation, the ϕ of differentiated systems, previously active systems which interfere with the excitation of newly active cs-systems from being organized, etc.

Here we focus on interference, which seems to underlie many of the factors listed above in some way or another. The immediate organization bias can also be seen as a mechanism which minimizes interference by stabilizing newly activated systems as soon as possible. Consider the sentences in (15)-(18), where in each set of sentences, the (a) examples seem more acceptable than the (b) examples, which are in turn more acceptable than the (c) examples. Furthermore, center embedding sentences in (15) and (16) are generally less coherent than their tail recursion counterparts in (17) and (18).

### (15) **Center embedding**

### (16) **Center embedding**

a. I saw Al, who Bo likes.

### 6 Grammaticality intuitions

### (17) **Tail recursion**

### (18) **Tail recursion**

A hypothesized interpretation trajectory for the center embedding of relative clauses in (16b) is shown in Figure 6.13. Note that we have omitted some intervening epochs in the trajectory to avoid clutter. As we hypothesized earlier the object relative [who]{rel} system +ϕ couples to the relativized {N} and −ϕ couples to a {V}. Thus in (e2) a [who]{rel} system +ϕ couples to [Al]{N}, and in (e3) a [who]{rel} system +ϕ couples to [Bo]{N}. We conceptualize these [who]{rel} systems as differentiations of a general {rel} system, just like [Al]{N} and [Bo]{N} are differentiations of {N}. Furthermore, we assume that a system is grounded after having participated in its expected ϕ-configuration, unless that system is relativized. Hence we imagine that [I]{PRO} and [saw]{V} are grounded after (e1) but [Al]{N} remains above-ground because it couples with [who]{rel} in (e2). Thus {rel} systems cause some other system to which they are coupled to remain excited.

Figure 6.13: Interpretation trajectory for a center-embedded relative clause.

### 6.2 Grammatical coherence

Given the above analysis, the first question we ask is: why is (16b) less likely to induce a coherent state than (16a)? One simple difference is that (16b) requires more ϕ-configurations to be simultaneously excited than (16a). This follows from our hypothesis that each [who]{rel} system +ϕ couples to an {N} and −ϕ couples to a {V}, along with our assumption that systems coupled to {rel} remain excited to participate in a configuration in a subsequent epoch. Having multiple systems of the same class simultaneously excited is potentially problematic because of differentiation interference. In the example there is s-differentiation interference between [Al]{N}, [Bo]{N}, and [Cam]{N}, and between [saw]{V} and [likes]{V}. There is also c-differentiation interference between [who] systems, and between [likes] systems, although the [likes] subsystems are not simultaneously excited.

Interestingly, because of the ϕ-configuration invariance principle, [Al]{N} and [Bo]{N} must have a ϕ-distal relation, while [Al]{N} and [Cam]{N} must have a ϕ-proximal relation. This follows from our hypotheses regarding role-to-ϕ patterns for [who]{rel}, transitive {V}, and agent/patient role {N}. Note that we use the term *relation* here rather than configuration because we do not want to imply that the ϕ pattern arises directly from ϕ-coupled s-systems. The [Al], [Bo], and [Cam] {N} systems must interfere through s-differentiation. Because (16b) is substantially worse than (16a), we might guess that the differentiation associated with proximally ϕ-related [Al]{N} and [Cam]{N} induces more interference than the differentiation associated with the distally ϕ-related [Al]{N} and [Bo]{N}. This makes a lot of sense given our speculation that {N} to {+N}/{−N} differentiation is relatively unproblematic compared to differentiation within {+N} or {−N}. In other words, differentiation of a system into two systems with proximal ϕ may induce more interference than differentiation into two systems with distal ϕ.

Perhaps most problematically, there is an epoch of the center embedding interpretation in which a newly activated system cannot be immediately organized. Specifically, in (e2) [Bo]{N} is coupled with a {rel} system but is not coupled to any lexical {V} system in (e3).

Indeed, the reason that the tail-recursive utterances in (17) and (18) are more coherent than their center-embedded counterparts in (15) and (16) is that each newly activated system can be immediately organized. A possible interpretation trajectory for the tail-recursion of (18c) is shown in Figure 6.14.

The tail-recursion in Figure 6.14 does not have any epochs in which a newly activated cs-system does not ϕ-couple to any previously activated or excited lexical system. In (e2) [Bo]{N} couples with [likes]{V} before the {rel} system couples to [Bo]{N}. This contrasts with (e2) of the center embedding in Figure 6.13, where [Bo]{N} couples with {rel}, and where epochs in which the |Cam likes| configuration arises intervene before the |Bo likes| configuration is organized.

### 6 Grammaticality intuitions

Figure 6.14: Tail-recursive trajectory: newly activated systems can be immediately organized.

Furthermore, the |likes who| configuration in (e2) of the tail recursion trajectory can be grounded in the transition to (e3), which avoids the circumstance where two {N}{rel} configurations are excited. Loosely speaking, we can attribute the difference in grammaticality intuitions for center embedding and tail recursion to difficulty in "keeping things in memory" longer. But more usefully, we see that the difficulty is the instability of keeping an {N} excited when it is not ϕ-coupled with a {V} and interferes with other {N} systems. In other words, coupling to {V} helps stabilize {N} systems and thereby diminishes interference between simultaneously excited {N} systems.

In addition to interference, "contextual" factors, i.e. the state of the surroundings prior to an interpretation, must have an influence on coherence. Consider the utterance in (19):

(19) read you a book on modern music?

The utterance in (19) probably does not induce a coherent trajectory on first interpretation. Now, read the list of utterances in (20):

	- b. have you a book on ancient music?
	- c. have you a dictionary of English?
	- d. want you a dictionary of English?
	- e. want you a book on ancient music?
	- f. want you a book on modern music?
	- g. seen you a book on modern music?
	- h. seen you a book on ancient music?
	- i. seen you a dictionary of English?

6.2 Grammatical coherence

The repetition of similar trajectories induces a structural priming effect. The last sentence coheres much more quickly than it did the first time around. Such effects suggest that every time some particular state trajectory occurs, trajectories which require a similar pattern of re-organizations can occur more quickly or with less interference, in interpretation of subsequent utterances. A variety of empirical studies provide evidence that such priming of this sort occurs and can have effects on a multi-day timescale (Bock et al. 2007; Ferreira & Bock 2006; Nagata 1988; 1992; Pickering & Ferreira 2008; Rowland et al. 2012). We can view such learning as macroscale changes in the forces which regulate ϕ-to-e mapping: the forces are altered to favor trajectories which are similar to a recently experienced one. There are many interesting questions that one might ask regarding the timescales on which such effects arise.

In contrast to the factors mentioned above, which are generally associated with interference, grammatical coherence does not appear to be as strongly affected by flavors of relational meaning. This can be inferred from the classic *colorless green ideas* example (Chomsky 1956), which does not evoke a strong unacceptability intuition. It does, however, seem to induce an atypical meaning experience.

(21) colorless green ideas sleep furiously

The example satisfies the utterance coherence criteria, and there is no reason to posit any particularly strong interference. Any oddness we experience in interpretation of the utterance must therefore derive from some other mechanism. One possible account of the oddness of the experience involves an aggregate effect of weakly activated, weakly interacting c-systems. Recall that we have assumed that interactions between c-systems are typically not very strong, particularly between lexical c-systems. This assumption is important because strong interactions would compromise flexibility of relational meaning experiences. Yet weak interactions are not the same as no interactions. Indeed, whenever a c-system is excited, many other c-systems must become active. Although we typically omit them from representations, these grounded systems may in the aggregate have a substantial effect on other c-systems. In Figure 6.15 we imagine that excitation of [green] induces ground-level excitation of many other c-systems that are associated with [green] (such as [leaf], [grass], [emerald], [apple], etc.), which

### 6 Grammaticality intuitions

we label as <green>. The c-systems <green> which are primed by [green] interact weakly with all of the c-systems <colorless> which are primed by [colorless].

Figure 6.15: Conceptual oddness can arise from many weak interactions between c-systems.

We might furthermore posit that these weak interactions between <green> and <colorless> are somewhat stronger because there is more population overlap/interference between more similar c-systems: c-systems associated with a commonly excited superordinate population like [color] may interact more strongly than c-systems which are not associated with a superordinate population, like [coffee] and [toothpaste]. The integrated effects of the <green>-<colorless> interactions may cause the experience of semantic oddness. Although a more detailed understanding of the experience is desirable, we infer it does not result from interference caused by s-system differentiation.

Many questions remain open regarding the factors which influence coherence. Although we have only scratched the surface of many issues, the o/el framework provides a useful basis for investigating intuitions as experiences. Importantly, we have rejected the distinction between grammaticality and acceptability. Our analysis of grammatical coherence has focused primarily on how coherence arises in interpretation. Another relevant question is whether coherent trajectories necessarily arise in production. Perhaps an invariant, stable ϕ-configuration arises in both production and interpretation, despite the lack of constraint on initial conditions. This similarity between production and interpretation is represented in Figure 6.16.

Production and interpretation are similar in that there are many possible initial states which may evolve toward the same locally invariant ϕ-configuration. In production, variation in e-organization can be used to select cs-systems in different orders (constrained by language-specific ϕ-e mappings), and yet all of these will evoke the same invariant ϕ-configuration for an interpreter. It is important to

Figure 6.16: Production and interpretation trajectories exhibit a local increase in order.

consider that both production and interpretation involve local increases in order. The local concentration of order only occurs when a system has work done on it by the surroundings; hence we deduce that both production and interpretation are driven by surroundings forces. Microscopically, these forces are presumably manifested from electrochemical gradients that the nervous system functions to maintain. In other words, coherence is possible because the microscale system self-organizes to a state in which macroscopic, coherent, ordered patterns arise.

# **6.2.5 Constituency intuitions**

What gives rise to intuitions about constituency, i.e. about how words are grouped, or organized? For example, in the utterance *Al drinks the cold coffee*, we experience an intuition that the words *the cold coffee* constitute a "group" in a way that the words *the cold* do not. In conventional terminology, *the cold coffee* is a constituent, while *the cold* is not a constituent. But what does it mean for words to "be grouped" or to "form a unit" when our conceptual model has no objectlike units, and thus no connection or containment of units? Here we show how we can understand these sorts of intuitions through analysis of coherence. Note that viewing constituency as intuitional rather than configurational (i.e. as a particular class of substate) is consistent with the observation that many ordering phenomena are not amenable to constituency-based analysis (Langacker 1997; Phillips 2003).

### 6 Grammaticality intuitions

Conventional phrase structure grammars account for constituency intuitions with the connection/containment blend whereby a node contains all of the nodes which are below it and connected directly or indirectly to it. Thus in the schema in Figure 6.17, *the cold* is not a constituent because there is no node which contains exactly those syntactic objects – the DP node also contains *coffee*. An additional constraint that non-trivial constituents must correspond to a phrasal node can be imposed, so that terminal elements such as *coffee*, *the*, or *cold* are only constituents in a vacuous sense.

Figure 6.17: Orientation and connection patterns are the basis for constituency in conventional frameworks.

Our intuitions about constituents are associated with constituency "tests", some of which are exemplified in Table 6.2 (cf. Carnie 2013; Ouhalla 1999 for more comprehensive introductions). Note that these tests are less applicable to verb phrase constituency and some other sorts of constituents; our focus here is on determiner-adjective-noun constituents.

The general procedure for conducting a constituency test is as follows. First, a candidate set of words ε is chosen from a base sentence, which in o/el terms is a trajectory ψ0 in which cs-systems associated with ε are selected. The trajectory is typically comprised of temporally contiguous e-epochs. In o/el terms this means that the trajectory is not interrupted by intervening epochs in which no systems are selected or in which systems other than ε are selected. Indeed, ε corresponds to a subpart of the trajectory ψ0 in a subspace of the system. The test is applied by constructing a test sentence (i.e. trajectory) ψCT, according to some particular pattern (e.g. topicalization, passivization, etc.). Grammaticality/acceptability (i.e. coherence) intuitions evoked from the sentence are then assessed to infer constituency.

In the case of the topicalization test, ψCT is a trajectory in which the candidate ε is the first part of the selectional phase of ψCT. The coherence intuitions

### 6.2 Grammatical coherence

Table 6.2: Noun phrase constituency tests.

that arise from this procedure for a variety of ε are represented in (22). The only ε which does not induce a relatively non-coherent experience is *the cold coffee*, and according to conventional analyses this is because these words exactly correspond to the words contained in a phrasal node. The conventional analysis of the topicalization test is somewhat unsatisfying because *cold coffee* could also correspond to a phrasal node (depending on various analytic choices) but nonetheless fails the test; further stipulations are necessary to explain why the topicalization pattern cannot apply to *cold coffee*.

	- b. \* the cold, Al drinks coffee.
	- c. \* the, Al drinks cold coffee.
	- d. \* coffee, Al drinks the cold.
	- e. \* cold coffee, Al drinks the.

The o/el re-analysis of constituency begins with a subtle but important point: we do not have intuitions about constituency until we interpret a potential constituent in some other context. More technically, constituency intuitions are *always* associated with the coherence of interpretation of a sub-part of a coherent trajectory, when that subpart is interposed in another trajectory. There are no "constituency intuitions" until we engage in a particular mode of interpretation which involves these metalinguistic trajectory manipulations. This conception not only leads to a new, useful understanding of constituency, based on the notion of coherence, but also explains why constituency intuitions do not accord

### 6 Grammaticality intuitions

with acceptability for patterns of ellipsis and anaphora, which we examine in detail in the next chapter. To illustrate, consider the following reference trajectory ψ0 , of *Al drinks the cold coffee*:

Figure 6.18: Reference trajectory for constituency tests: *Al drinks the cold coffee.*

To assess the constituency intuition for *the cold coffee*, we identify the trajectory in Figure 6.18 of epochs (e3–e4), in which [the]{D}, [cold]{Adj}, and [coffee]{N} are selected. We construct the candidate trajectory ε by ignoring state space dimensions associated with other non-test systems in (e3–e4), i.e. dimensions related to [Al]{N} and [drinks]{V}. However, we take note of the ϕ-configurations which involve the test systems and non-test systems, since we attempt to integrate these with the constituency test trajectory ψCT. We then construct ψCT, by combining ε and ψCT according to a desired pattern. This construction procedure predetermines which patterns are suitable (e.g. topicalization, clefting, passive, pseudocleft). Patterns which omit or replace ε(i.e. ellipsis, anaphora) lead to different intuitions about grouping, as does coordination.

A test trajectory for topicalization of the candidate *the cold coffee* is shown in Figure 6.19. Although immediate organization of [coffee]{N} with a {V} system is not possible after (e1), excitation of [drinks]{V} in (e3) allows [coffee]{N} to participate in a ϕ-configuration. We can further hypothesize that after epochs of initial system excitation (e1–e3), a coherent reiterative simulation (e3, e3′) can arise, in which utterance coherence criteria are met. This analysis entails that constituency intuitions arise from experiencing the achievement of a coherent trajectory, and not necessarily from an experience of the path that is taken to achieve that trajectory.

In contrast to *the cold coffee*, the topicalization test of *the cold* does not lead to a coherent state. The likely reason is shown in Figure 6.20: neither [cold]{Adj} nor [the]{D} can ϕ-couple to the lexical {N} system [coffee]{N}, which is necessary for the expected ϕ-configurations of {Adj} and {D}. This raises the question of why in (e4) [the]{D} and [cold]{Adj} cannot couple to [coffee]{N} and thus give rise to the ϕ-configuration required for coherence. One possibility is that the immediate

6.2 Grammatical coherence

Figure 6.19: Topicalization test trajectory for constituency of *the cold coffee*.

organization bias is stronger for {D} and {Adj} systems than for {N} systems. It may be more difficult to maintain {D} and {Adj} systems in an unstable state across multiple epochs than it is to maintain {N} systems.

Figure 6.20: Topicalization test trajectory for a non-constituent does not lead to a coherent state.

Similar accounts can be extended to passivization, pseudocleft and cleft tests, shown in Figure 6.21. The grayed ϕ-configurations with {D} and {Adj} are ones which, because of the intervening epochs, are unable to participate in the expected configuration. There may be other reasons why coherence does not occur in these examples. For instance, [cold] might couple to an {N} system, which allows for immediate organization with [is]{Aux} in all three examples. In the cleft, [cold] might couple with [Al]{N}, in which case [drinks]{V} would have no {N} system to +ϕ couple with because [Al]{N} couples with [is]{Aux}. Thus the immediate organization bias may be an important factor in determining the coherence intuitions associated with constituency.

There may be a variety of additional reasons why coherence is not achieved when some particular ψCT is constructed, and a more comprehensive analysis is desirable, one which could predict when coherence is expected in a broader range of constituency tests. The o/el framework nonetheless brings us some clarity by discouraging us from thinking of "constituents" as objects; instead, we reconceptualize constituency as a phenomenon which derives from experiences

Figure 6.21: Non-coherence in passive, cleft, and pseudocleft constituency tests.

of coherence or the lack thereof. This requires us to refocus our investigations of constituency phenomena on temporal patterns in interpretation, as opposed to atemporal, abstract structural relations.

# **6.3 Electrophysiological and behavioral manifestations of coherence**

Grammatical coherence on the utterance scale depends on epoch scale coherence, which in turn depends on auto-spectral and cross-spectral coherence of excited c- and s-systems. Thus spectral coherence is the fundamental basis for many aspects of grammaticality intuitions. Here we show how spectral coherence can be related to electrophysiological and behavioral phenomena, specifically focusing on event-related potentials (ERPs) in sentence processing. In order to accomplish this, we first develop a set of linking hypotheses. The coherence phenomena analyzed below are assumed to occur before the reiterative trajectories which are necessary for grammatical coherence; intuitions regarding grammatical coherence are dependent on and arise subsequently to the electrophysiological manifestations of spectral coherence. By means of its emphasis on coherence, the o/el framework provides an alternative vocabulary for understanding various psycholinguistic phenomena.

# **6.3.1 Linking hypotheses for spectral coherence**

One of the major methodological instruments used to study syntactic and conceptual processing is electroencephalography (EEG). EEG measures voltage fluctuations generated by neural spiking in the brain, using electrodes placed on the

### 6.3 Electrophysiological and behavioral manifestations of coherence

scalp. When EEG signals are aligned to the time at which a stimulus is presented, changes in measured voltages are observed – these are called event-related potentials (ERPs). A number of different ERP patterns have been identified. These are hypothesized to be associated with syntactic and/or semantic "processing," a concept which we reinterpret in the current framework. ERPs are commonly given names which refer to when and/or where they are observed, along with whether the observed voltages are negative or positive relative to a reference voltage. For example, researchers have identified an "N400" which is a negative voltage change that occurs in association with semantic processing, a "P600" which is a positive voltage change that occurs in association with syntactic and/or conceptual reanalysis (as in the interpretation of garden path sentences), and an "ELAN" (early left anterior negativity) which is associated with syntactic category processing.

Here we develop a set of linking hypotheses which allow for the o/el model to generate ERP patterns that are in some ways qualitatively similar to observed ERPs. The key idea behind this approach is that "processing" – a rather vague term – can be reinterpreted more mechanistically as change in the auto-spectral coherence of c- and s-systems, and change in the cross-spectral coherence of cssystems. For reasons that are made clear below, our focus is on the time-course of such changes as a function of stimuli, rather than their spatial distributions in the brain.

When a single neuron spikes or receives input from other neurons, there is a transmembrane ionic current associated with changes in membrane potential. When the axons of many neurons are oriented similarly in space, the voltage changes associated with individual neurons and synapses combine to create a change in the electrical potential which is measurable above the scalp. Thus the EEG signal is an integration of state changes in many neurons which have similar orientations. Axons of pyramidal cortical neurons generate most of the cortical EEG signal because these are closest to the scalp (Federmeier & Laszlo 2009; Kutas & Dale 1997). The extracellular fluid and cranium act as coarse spatial filters on the signal, and hence the spatial resolution of EEG is poor compared to other measurement techniques such as fMRI. Furthermore, the mathematical problem of localizing the origins of EEG signals in the brain is underdetermined. However, the temporal resolution of EEG is far superior to fMRI and thus it is better suited to investigating the time-course of syntactic/semantic processing.

Even in the absence of sensory stimuli, the brain exhibits EEG signals with power at a range of frequencies (Buzsaki 2006). These oscillations are thought to provide a basis for interactions between brain areas, and to facilitate processing of sensory stimuli (Fries et al. 2001; Gray et al. 1989). Event-related potentials

### 6 Grammaticality intuitions

(ERPs) are measured by presenting a stimulus and averaging the stimulus timelocked electrical activity over a large number of trials. The assumptions behind this approach are that the electrical response to the stimulus is of fixed polarity and occurs at a fairly consistent latency relative to stimulus presentation (Penny et al. 2002). The averaging is necessary because there is typically a large amount of neural activity that is not specific to the stimulus (i.e. noise). There are two main theories on the neural origins of event-related potentials (ERPs): the phase resetting (phase modulation, PM) theory and the evoked response (amplitude modulation, AM) theory (Makeig et al. 2002; Penny et al. 2002; Shah et al. 2004).

In the evoked response theory, stimuli "evoke" a neural population response, and EEG power increase is expected in a single trial. Averaging evoked responses over multiple trials amplifies this power increase and thereby produces the ERP pattern. In the phase-resetting theory, sensory stimuli induce a phase-reset of ongoing EEG rhythms. Under this view, the reason the ERP pattern is observed is due to averaging over trials: in a single trial, no increase in neural activity is expected, but the EEG rhythm will be phase-coherent across trials when timealigned to the stimulus onset; hence averaging over multiple trials is necessary to observe an ERP, which reflects phase-coherence. Another possibility is that both phase-modulation and amplitude modulation influence ERPs (Penny et al. 2002; Shah et al. 2004). For current purposes we assume that both of these effects contribute to coherence.

Many language-related ERP studies investigate sentence processing by comparing ERPs between conditions in which some relevant syntactic or semantic aspect(s) of sentences are varied. The comparisons are made by aligning EEG signals to the time when a manipulated word is presented in a sentence. It is important to keep in mind that there is an EEG signal response to the presentation of each word in a sentence, and that the response to any given word is often influenced by responses to preceding words. Thus the dynamics of the EEG signal in response to any particular utterance are quite complicated.

A set of linking hypotheses is necessary to relate power changes in the EEG signal – (and ultimately, ERPs) – to spectral coherence dynamics in interpretation trajectories. To illustrate these hypotheses we consider c- and s-system coherence trajectories and their first-derivatives in a canonical interpretation trajectory for *Al drinks coffee*, shown in Figure 6.22. As each word is perceived, sensory systems are excited (not shown). The specific pattern of excitation of sensory systems will in general be based on acoustic information of the stimuli (in the case of auditory stimuli) or visual information (in the case of graphemic/orthographic stimuli), but may also be influenced by "top-down" influences from previously excited conceptual and syntactic systems. Note that we have not developed a

### 6.3 Electrophysiological and behavioral manifestations of coherence

specific model of sensory systems in the o/el framework – such systems have generally been subsumed as part of the surroundings of c- and s-systems. Approximately 40-50ms after stimulus onset, active sensory systems begin to exert forces on both c- and s-systems, causing them to become excited. The particular c- and s-systems which experience these forces necessarily depend on learned associations between sensory systems and c-/s-systems. For example, we have learned that the auditory or visual stimulus *Al* excites an {N} s-system and [Al] c-system. Of course, other c- and s-systems may also be excited by the stimulus, particularly in cases of homophony, and the extent to which a given c- or s-system may be excited by a stimulus is conditioned by learning (i.e. supra-utterance scale system evolution) and context (forces from the surroundings which evolve on the utterance scale).

When the sensory systems activated by *Al* begin to activate {N} and [Al] systems, those systems begin to evolve toward an active state in which the individual neurons in the relevant populations are collectively oscillating. Thus there will be a transient period of time in which the auto-spectral coherence of each system is increasing. Recall that our microscale conception of the coherence process is that individual neuronal spikes within the population become more predictable and correlated, and on the macroscale this results in a narrowing of the power spectrum of the system, i.e. the emergence of a more ordered state. The power spectra of c- and s-systems at selected points of time are shown in Figure 6.22. Both the widths and peak amplitudes of the spectra are assumed to be related to the coherence of the systems; the increase in coherence is modeled here with a first-order differential equation: ̇x = −a (x − xmax), where a is a fixed growth rate parameter and xmax is an equilibrium which represents a maximal degree of coherence.

There are several key features of the trajectories to notice. First, although the s-systems and c-systems associated with a stimulus are activated at the same time, the c-system cannot reach an above-ground state until after the s-system does. This reflects the hypothesis that excitation depends on the emergence of a cs-resonance. Second, there is "priming" for both c- and s-systems. For example, shortly after the {V} system is excited, an {−N} system is activated. Likewise, shortly after the [drinks] system is excited, a [coffee] system is activated. These priming effects are assumed to be pervasive, particularly for c-systems: presumably [drinks] activates a large number of c-systems (e.g. [tea], [whisky], etc.). Note that only priming of [coffee] is shown here in order to avoid visual clutter. A crucial consequence of the priming is that when the *coffee* stimulus does occur, the {−N} and [coffee] systems already have some degree of coherence, and hence the change in coherence that is necessary to reach an above-ground state

is smaller. This also results in a shorter period of time from the stimulus onset to the emergence of an above-ground [coffee]{−N} system. Finally, e-organization operations are shown here to occur after all three cs-systems have been excited; this aspect of the system trajectory is a somewhat arbitrary choice, rather than a necessity. It is possible that |Al drinks| could be e-organized in a more incremental fashion, prior to the emergence of the |coffee {−N}| system.

Figure 6.22: Coherence and coherence process signals of s-systems and c-systems in an interpretation trajectory.

The coherence trajectories shown for s-systems and c-systems above can be used to generate ERPs. Specifically, a short-time integration of the magnitude of the rate of change of coherence is hypothesized to correlate with power of the EEG signal. We emphasize that it is the *magnitude of the rate of change of spectral coherence*, rather than coherence itself, which is the relevant predictor. This follows from reasoning about how coherence is achieved on the microscopic scale. Coherence in a given population is reflected in the temporal distribution of spikes, or in other terms, their predictability/correlation or degree of order. Coherence is achieved over a period of time when the interactions between neurons in the population and interactions with other populations induce an excited state,

### 6.3 Electrophysiological and behavioral manifestations of coherence

which entails a narrow spectral peak. If a population takes longer to reach the excited state, there will be more spiking in the population. Furthermore, when the population is initially activated, differentiation interference experienced from other populations is expected to be larger, and the size of the population (number of neurons which interact) may be larger – the population will to a greater extent include or interact with neurons from populations which are associated with other systems. Thus in order for the population evolve to the excited state, microscopic interactions are necessary, and more of these interactions entails more neural spiking. The microscopic considerations therefore point to *changes* in coherence as the most direct predictor of EEG power, rather than the excitation levels of systems.

Changes in coherences in the trajectory in Figure 6.22 are the envelopes of the filled regions in the panels labelled "s-system coherence" and "c-system coherence". Power spectra of the integrated spiking rates of systems are shown at selected timepoints. These power spectra are understood to evolve continuously and require an analysis window that is sufficiently large to resolve the lowestfrequency components of the population spiking rate. As discussed previously, the process of achieving a degree of coherence sufficient for excitation involves a narrowing of the frequency distribution. The widths and peak amplitudes of these spectra are assumed to be related to the coherence signals shown for the ssystems and c-systems. It is important to note that the coherence signals here are constructed from the simplifying assumption that coherence evolves as a linear system toward an equilibrium value – an important long-term endeavor in the o/el framework is to develop a microscale model of population dynamics from which integrated spike rate can be derived, in turn allowing for derivation of coherence and order parameters (i.e. e and θ).

Another assumption depicted in the spectra is that the peak frequencies of the systems are initially different. The frequency locking process was modeled here with first-order systems that evolve toward a time-varying equilibrium that is the coherence-weighted average of the peak frequencies of all of the s-systems and c-systems which are ϕ-coupled. Thus the peak frequency {V} of evolves toward a value that is the weighted average of the peak frequencies of {+N}, {V}, {−N}, and [drinks]; in contrast, the peak frequency of [drinks] evolves toward a value that is the weighted average of only {V} and [drinks]. Hence the frequency dynamics reflect the fundamental principle that s-systems are strongly ϕ-coupled to each other and resonate with a c-system. The overall effect of the frequency dynamics is that s-system peak frequencies evolve to a common frequency more quickly than c-system peak frequencies. This in turn has consequences for cross-spectral

### 6 Grammaticality intuitions

coherence: cross-spectral coherence of s-systems is expected to increase before cross-spectral coherence of c-systems.

In order to facilitate the interpretation of ERP effects as changes in coherence, *coherence-process signals* are calculated from the magnitude of the first derivative of coherence. This magnitude is low-pass filtered (using a rectangular-window moving average), which approximates a short-time integration of changes in coherence. The resulting signals are called "coherence-process signals" because they arise from the process of achieving coherence; they should not be confused with auto-spectral or cross-spectral coherence. Several different coherenceprocess signals are shown in the bottom panel of Figure 6.22. The s-system coherence process signals are summed over the {+N}, {V}, and {−N} systems; likewise the c-system signals are summed over the [Al], [drinks], and [coffee] systems.

In theory, other coherences are also relevant, particularly the cross-spectral coherence between s-systems and c-systems, and between cs-systems. However, cross-spectral coherence cannot be calculated without phase information, which in turn cannot be calculated without a model that generates an explicit spike-rate time series. In the absence of such a model, cross coherences are approximated by the products of power spectra. The cross-coherence-process signals shown in the figure are thus low-pass filtered derivatives of the integration over frequency of products of spectra, summed over the relevant pairs of systems. Specifically, the s-system cross-coherence-process signal is the sum over the crosscoherence-process signals of {+N}{V}, {V}{−N}, and {N}{−N}; the c-system crosscoherence-process signal is the sum over the cross-coherence-process signals of [Al][drinks], [drinks][coffee], and [Al][coffee]; and the c-s cross-coherenceprocess signal is the sum over the cross-coherence-process signals of {+N}[Al], {V}[drinks], and {−N}[coffee].

In general, all of the coherence process signals may contribute to the EEG signal, but for current purposes we will focus on only one or two such signals to analyze ERP effects. Ultimately, the set of assumptions and approximations in the above model should be viewed together as an ansatz, an educated guess which may or may not be verified by its results. As we see below, the results are in many ways qualitatively consistent with observations.

# **6.3.2 Relations between coherence and ERP patterns**

The first ERP we analyze is the ELAN (early left-anterior negativity), which is a negative peak observed from 100-300 ms after stimulus presentation. The ELAN is associated primarily with identification of the syntactic category of a word (Friederici 2002; Hahne & Friederici 1999; Steinhauer & Drury 2012). The main

### 6.3 Electrophysiological and behavioral manifestations of coherence

empirical finding is that a word whose syntactic category is relatively unexpected results in an increase in the amplitude of the peak, compared to words whose syntactic category is relatively expected, given prior context. For example, in (23a), a word that is a noun such as *coffee* is expected given that the preceding word *drinks* is a transitive verb; in (23b) the preposition *on* is less expected.

(23) a. Al drinks coffee.

category matches expectation: smaller ELAN

b. Al drinks \*on coffee. category mismatches expectations: larger ELAN

In o/el terms, activation of a less expected system – e.g. the {P} s-system in (23b) – elicits a larger negative peak than activation of a more expected system – e.g. the {−N} s-system in (23a). This can be described as a priming effect: the word *drinks* excites a {V} s-system which resonates with [drink], and also activates a {−N} system which will typically resonate with a subsequently activated c-system. This priming effect is shown in Figure 6.23 where {−N} is activated shortly after {V}.

Figure 6.23: Early left anterior negativity (ELAN): activation of less expected s-system results in a larger coherence-process signal than activation of a more expected s-system.

There are several reasons why the coherence-process signal after presentation of the mismatching category {P} is greater than the signal when the expected {N}

### 6 Grammaticality intuitions

is presented. Because the {−N} system is already activated, a smaller increase in coherence is required to achieve an excited state when *coffee* is presented compared to the increase required for the {P} system to reach a coherent state when the preposition *on* is presented. Hence one source of the ERP effect is that excitation of {P} requires a greater change of coherence, and as elaborated above, coherence-process signals reflect an integration of changes in coherence. Another possible source of the ERP effect may be interference between {P} and {−N}. This interference is expected to slow achievement of coherence of {P} and possibly decrease the coherence of {−N} – these effects are illustrated in Figure 6.23 as well. An increase in the period of time over which coherence is achieved, and a change in the coherence of the already active {−N}, both contribute to a larger coherence-process signal.

The next ERP we consider is the N400, which is a negative peak observed from 300-500 ms after stimulus presentation. The amplitude of the N400 is inversely correlated with the extent to which a word is semantically expected (Federmeier & Laszlo 2009; Friederici 2002; Kutas & Federmeier 2011). For example, the c-system [coffee] which is activated by utterance (24a) is more expected than the c-system [toothpaste] activated in (24b).The word *coffee* has a greater cloze probability than *toothpaste* in this context, i.e. a greater likelihood of completing the sentence *Al drinks*.

	- concept more consistent with expectations: smaller N400
	- b. Al drinks toothpaste. concept less consistent with expectations: larger N400

The analysis of the N400 is directly parallel to the analysis of the ELAN: [coffee] is primed by [drinks] to a greater extent than [toothpaste], and hence the achievement of coherence of [toothpaste] requires a greater change in coherence than [coffee]. The key difference between the ELAN and the N400 is that the ELAN arises from activation of s-systems, while the N400 arises from activation of c-systems. As described above, c-system excitation is delayed relative to s-system excitation, because c-system excitation requires resonance with an excited s-system.

The N400 effect does not require a sentential context and is influenced by a number of factors which include semantic category membership, word frequency, and neighborhood density (Kutas & Federmeier 2011; Lau et al. 2008). In lists of words in which a semantic category expectancy is generated, a word whose semantic category deviates from the expectation will induce a larger N400.

### 6.3 Electrophysiological and behavioral manifestations of coherence

Figure 6.24: N400: activation of less expected c-system results in a larger coherence process signal than activation of a more expected csystem.

For example, in the utterances in (25), *toothpaste* will induce a larger N400 than *wine*. The N400 is sensitive to word frequency as well: in the utterances in (26), *ouzo* will induce a larger N400 than *coffee*. In both cases, it is sensible to assume that prior to presentation of the stimulus *wine*, a [wine] system is already active to some degree, and hence a smaller change in coherence of [wine] occurs post-stimulus than in cases where the stimulus-activated c-system has been preactivated to a lesser degree. In other words, the frequency effect arises because [drinks] activates ("primes") a higher-frequency c-system like [wine] to a greater extent than a lower-frequency c-system like [ouzo].

	- b. coffee, tea, whisky, toothpaste
	- b. Al drinks ouzo.

The interpretation of neighborhood density effects on the N400 is somewhat different from the effects discussed above. A word with a denser neighborhood will induce a larger N400 than a word with a sparser neighborhood (Holcomb et al. 2002; Müller et al. 2010). This effect should be understood to arise because stimuli with denser neighborhoods will activate more c-systems than those with

### 6 Grammaticality intuitions

sparser neighborhoods. When more c-systems are active, there is more competition between c-systems for a cs-resonance and the c-systems interfere with each other to a greater extent. Hence it will take longer for a coherent cs-resonance to emerge than in a condition where fewer c-systems are primed.

An interesting finding regarding the N400 is that it is often insensitive to negation (Kutas & Federmeier 2011). Hence N400s for *toothpaste* are similar in *Al drinks toothpaste* and *Al do not drink toothpaste*. This suggests that negation and possibly quantification in general does not influence the priming effects that modulate the amplitude of the N400. This raises questions regarding relational meaning experiences which involve negation and quantification; an analysis of such meaning experiences has not yet been developed in the o/el framework.

In the same time period as the N400, a left anterior negativity (LAN) is sometimes observed in response to morphosyntactic agreement violations (Friederici 2002; Gunter et al. 2000; Kutas & Federmeier 2011; Osterhout & Holcomb 1992). For example, *the students drinks coffee*, where the verbal number agreement mismatches the number of the subject argument, will elicit a greater N400 than *the student drinks coffee*. This suggests that excitation of grammatical s-systems (i.e. {number}, {person}, {tense} etc.) occurs later in time than excitation of lexical ssystems (i.e. {N}, {V}, {P}, etc.), where expectation mismatches are associated with the ELAN. This is consistent with the notion that grammatical s-systems must be coupled to excited lexical s-systems in order to become excited themselves. This accords with the idea that the utterance *the*, which excites only {D}[definite], does not give rise to a coherent configuration: there is no lexical cs-resonance for {D}[definite] to couple with. It should be noted, however, that agreement violations do not always appear to elicit a LAN effect, but instead may elicit a later effect called the P600, which we consider next. In these cases, both prior syntactic and conceptual excitation may be required for effects to manifest in coherence-process signals.

The P600 is a positive EEG signal occurring from 600-1000 ms after a stimulus. The P600 has a centro-parietal location, as opposed to the left-anterior locations of the ELAN and LAN. It has been associated with syntactic violations, processes of reanalysis and repair (as in garden-path sentences), and syntactic complexity (Friederici 2002). Although some researchers view the P600 as a languagespecific ERP component, others have argued that the P600 is not distinct from the more general P3, an ERP that is associated with attention-related reorientation behavior (Sassenhagen & Bornkessel-Schlesewsky 2015). This raises the question of whether in the o/el model the P600 (or P3) can be understood differently from the ELAN, N400, and LAN, all of which are attributable to priming, i.e. pre-stimulus activation of systems below the excitation threshold.

### 6.3 Electrophysiological and behavioral manifestations of coherence

To address this, let's consider a garden path sentence such as *Al drinks coffee and tea is brewing*. Assume that in the garden-path interpretation there is a state in which an |Al drinks coffee| configuration is excited, followed by a state in which an |Al drinks tea| configuration is excited. Upon occurrence of the stimuli *is brewing*, the relevant cs-systems [be]{aux} and [brew]{V} become active, but because [tea]{N} is already coupled to [drink]{V}, [tea]{N} is not able to couple stably to [brew]{V}. This results in [brew]{V} failing to achieve coherence. We conjecture that this non-coherence induces a "repair" process, which involves selectively grounding e-operations and subsequent reorganization operations. If the reorganization leads to a grammatically coherent trajectory, the repair is successful. However, the grounding and reorganization e-operations that occur during the repair result in many changes in spectral and cross-spectral coherence, which are manifested as changes in EEG power. This is illustrated in Figure 6.25.

Figure 6.25: P600 in a garden-path interpretation: detection of noncoherence and reorganizations for repair result in a large coherenceprocess signal.

One question we might ask is why the P600 has a different spatial distribution and sign than other ERPs. Consider that there are several differences in the mechanisms which cause coherence changes during a repair, compared to those associated with priming effects. For starters, the ELAN and N400 are associated with the timecourse of excitation of cs-systems, which occurs prior to the emergence of a stable configuration; this excitation does not necessitate any e-organization. In contrast, the P600 is associated with e-operations on already-excited

### 6 Grammaticality intuitions

or already-activated systems, and hence is expected to occur later. Secondly, it may be useful to construct *coherence-response systems*, which are systems which become active when cs-states are non-coherent. Coherence response systems provide a mechanism for "monitoring" the state of the system, and likely play a role in shaping grammaticality intuitions discussed earlier. It would not be surprising if coherence response systems have a different spatial distribution than cs-systems, but the imprecision in spatial localization of ERP generators warrants caution in drawing inferences in this regard.

# **6.3.3 Toward a new vocabulary of psycholinguistic analysis**

The o/el framework offers an alternative vocabulary for interpreting psycholinguistic observations of behavior. There are several advantages of this vocabulary: (i) It brings temporal phenomena to the fore with a conceptual model that is focused on dynamics. (ii) It avoids potentially misleading anthropomorphizations. (iii) It provides a basis for a more specific conception of *information*. (iv) It avoids conceptual dissonance that arises in describing phenomena which necessitate simultaneous reference to incompatible structures.

To illustrate these advantages, let's consider how ERP effects are typically described in psycholinguistic literature. Such effects are commonly attributed to "mismatches," "processing difficulty," or "reanalysis/repair" (see e.g. Friederici 2002; Kutas & Federmeier 2011). For instance, the ELAN is understood as the result of a mismatch between the syntactic category of a stimulus and the expected category, which occurs in a process of word category "identification". The N400 is understood as an index of difficulty in "processing" which occurs in the "integration" of semantic and syntactic "information". The P600 is understood as an index of complexity or the need for "reanalysis".

Psycholinguistic studies do not always provide more specific details regarding what these terms mean in the context of a conceptual model of syntax. Basic questions arise which call for detailed answers: what is "processing"? What does it mean to "identify" a syntactic category? What form does the "expectation" of a category take? What is a "category", anyway? Object-based conceptions do not readily help us understand the behavioral manifestations of processing, because objects are atemporal. In contrast, the systems of the o/el framework evolve in time and are characterized in terms of states. Thus "identification" of a category can be understood as a state space trajectory in which sensory systems activate conceptual and syntactic systems, and in which those systems subsequently evolve from an active state to an excited state, via coupling/resonance

### 6.3 Electrophysiological and behavioral manifestations of coherence

mechanisms. The microscale conceptual model further informs our understanding of the trajectory by allowing us to think of the evolution as emergence of spectrally coherent collective oscillations in neural populations. The *trajectory* IS the "processing," and there are no categories, but rather, *systems*.

The concept of "processing information" is potentially misleading for a couple reasons. First, *processing* evokes a computational interpretation of phenomena, and most computational models impose temporally discrete operations on system states. The states of systems we have constructed are understood to evolve continuously in the pre-stable phase of trajectories, and this evolution should not be viewed as the consequence of discrete operations. Of course, discrete computations applied in the limit of infinitesimally small time increments provides an effectively continuous approximation to system dynamics, but computational interpretations in linguistic theories rarely adopt this infinitesimal limit construal. Thus use of the word *processing* has the potential to evoke a counterproductive discretization of time in pre-stable phases of system state trajectories. Second, the computational interpretation tends to evoke symbols, because many computational models of language are developed to manipulate symbolic representations, rather than states defined in continuous dimensions. Because symbols are objects, any interpretation of behavior which evokes them will lead to many of the problems of the object metaphor which we have discussed in this book.

In a deeper sense, the interpretation of information processing as symbol manipulation unnecessarily obscures the nature of the state space and thereby leads to an inadequate conception of *information*. What do people mean when they say that the brain "processes information"? The word *information* seems to be often used in a non-technical sense, and is rarely defined in a rigorous manner. The tenets of information theory (Shannon 1948) hold that information is *produced* when a previously undetermined (or unobserved) system state is determined (or observed). The information produced by the determination process is measured as the change in entropy (H) of the system from before determination to after determination. The entropy is the negative sum of the log probabilities of states, weighted by their probabilities, as shown in the equation below. Thus information is entropy lost in the determination of a system state.

(27) Information produced = Entropy before – Entropy after

$$\mathbf{H} = -\sum\_{\mathbf{i}} \mathbf{p}\_{\mathbf{i}} \log \left( \mathbf{p}\_{\mathbf{i}} \right) = -\mathbf{p}\_{\mathbf{1}} \log \left( \mathbf{p}\_{\mathbf{1}} \right) - \mathbf{p}\_{\mathbf{2}} \log \left( \mathbf{p}\_{\mathbf{2}} \right) - \dots - \mathbf{p}\_{\mathbf{n}} \log \left( \mathbf{p}\_{\mathbf{n}} \right)$$

In the case of a system which generates equiprobable discrete states, such as a coin flip or a random selection of a character from the alphabet, the information

### 6 Grammaticality intuitions

that is produced from each flip or character selection (i.e. from the determination process), increases when there are more possible states: hence there is more information produced by selecting a character of the alphabet than by flipping a coin. In both cases, the entropy after determination is zero – the system state is fully determined, but the number of possible states before determination is greater for the alphabet, which has 26 possible states, than for the coin, which has only 2. The same reasoning can be generalized to continuous variables, in which case it is the probability-weighted volume of the state space before determination that matters for calculating the information that is produced. It is crucial to recognize that a state of the system itself does not "have information," but rather, information is something that is "gained" by a reduction of volume of the state space or "lost" by an increase of volume of the state space. Furthermore, the first terms in the products in the entropy equation, which are probabilities of states (pi ), are weighting terms which specify how much each sub-volume of state space contributes to the total entropy associated with the space. The information gained by determination of a state is maximal when those probabilities are uniformly distributed over the space.

How does the technical understanding of information gel with the o/el conception of a state space trajectory? The o/el analysis might seem to imply that no information can ever be lost or gained: the system state is always determined, and evolves according to deterministic laws; thus there is no determination process which allows for a change in entropy. However, consider that our analyses always partition the full system state into systems and a surroundings: it is only the systems whose states are always determined; the surroundings state is never determined. Hence entropy can be transferred from systems to the surroundings. Indeed, this is exactly what happens on the microscale when a c-system or s-system becomes active: the entropy of the population decreases, by means of being transferred to the surroundings. This entails a reduction in the number of accessible microstates of the system, but not of the universe.

Alternatively, we can say that the order (i.e. negentropy, see Schrödinger 1944) of the system increases. Thus information has been produced *locally*, i.e. in the region of state space which is relevant to describing the system. This local increase is always offset by an increase of entropy in the surroundings, and according to the second law of thermodynamics is always greater than or equal to the local decrease. It is more appropriate, in o/el terms, to think of "information processing" as local increase or decrease of order in systems. The advantages of this perspective are that we allow for a more detailed accounting of the temporal evolution of probability mass in state space, and are better able to see the connection between

### 6.3 Electrophysiological and behavioral manifestations of coherence

information and our analytical choices in partitioning the universe into systems vs. surroundings.

Another advantage of the o/el conception is that "expectation" or "prediction" of a category or meaning are not associated with an ad hoc, anthropomorphic mechanism. Instead, a more phenomenologically neutral description is available in which the activation of a system induces activation of other systems which are likely to become active in the future. This mechanism allows us to understand ELAN, LAN, and N400 effects just as readily as conventional vocabularies. "Prediction" is problematic because it evokes a potentially misleading anthropomorphization of the system. The verb *predict* entails an animate agent (cf. *Bo predicted Al would drink coffee* vs. ?*The table predicted Al would drink coffee*). There is no theoretical necessity to conceptualize the system as animate, or as the sort of entity which "makes predictions". Rather, we say that the system state evolves such that its location in state space tends to move closer to states which are statistically more likely to arise in the future. This aspect of the system is a consequence of supra-utterance scale "learning" mechanisms which are viewed microscopically as changes in within- and between-population interactions.

The conventional vocabulary often employs terms like *reanalysis* or *repair*. But what is being reanalyzed, and what entity is doing the reanalyzing? In some cases authors propose to interpret these terms with object-based representations. For example, reanalysis has been described with substitution and adjunction operations on elementary trees in a tree-adjoining grammar conception (Ferreira et al. 2004). Thus reanalysis involves the unmerging of some objects, while keeping those objects present, in order to re-merge them subsequently. One problem with this sort of conceptualization is that is does not predict any inherent cost for the "floating structures" or "unintegrated objects" which arise in such models, nor for the operations which create them. Why should object structures which are not connected to other object structures be problematic? It is certainly possible in such models to stipulate that unmerged objects give rise to processing difficulty, but this does not address the question of *why* the processing difficulty arises, or what "processing" is in a mechanistic sense.

The o/el framework provides greater clarity regarding what processing is, what "unintegrated structures" are, and why the reanalysis that produces them leads to behavioral effects such as increased P600, slowed reading times, and/or saccadic backtracking. In conventional approaches, unintegrated structures are structures of objects that are not merged into some other structure which is already present. Instead of imagining of objects in space, the o/el conception posits systems which can be characterized by their spectral coherence and coupling to other systems. Unintegrated structures are cs-systems which are (i) not

### 6 Grammaticality intuitions

coupled to other cs-systems and (ii) are not spectrally coherent. A consequence of these conditions is that these systems experience stronger interference from other systems, and are therefore less stable. The repair process, as described in our analysis of the P600, involves the application of grounding and subsequent reorganization operations. This allows for alternative ϕ-configurations to arise, and subsequently for a grammatically coherent interpretation trajectory to occur. The initial instability and the reorganization operations are associated with changes in spectral coherence which manifest in ERPs. We have furthermore conjectured that there may be *coherence response systems* which respond to noncoherent states by inducing reorganizations. Along these lines, a sensible endeavor is to develop a model of oculomotor control in which coherence response systems influence reading behavior; this will allow for reading time and saccadic backtracking to be modeled in the framework.

One of the most fundamental problems with object-based conceptions of psycholinguistic phenomena is that they do not lend well to reasoning about the "parallel" activation of systems. Consider the garden path utterance in (28) below. The interpreter may excite a |dressed baby| configuration, but this leads to a non-coherent state because [played]{V} cannot participate in a ϕ-configuration with a {+N} system. The experience of non-coherence may then induce reorganizations which lead to a coherent trajectory involving |Al dressed (himself)| and |baby played| configurations. Psycholinguistic studies have found evidence that the garden-pathed relational meaning of |dressed baby| may "linger," based on the observation that interpreters will sometimes answer "yes" to question (29a) (Slattery et al. 2013), indicating that the originally engaged configuration remains in memory after the repair.

	- b. Did Al dress himself?

The issue here is how to conceptualize working memory and "lingering structures". As we explored earlier, a standard mapping of the object metaphor is that two linguistic units cannot occupy the same position in a structure, just as two different objects cannot occupy the same space. Thus in order to adapt a conventional conceptualization of structure to account for this sort of phenomenon, it is necessary to circumvent violations of the standard mapping. To wit, Slattery et al. (2013) describe an account in which there is an "overlay function" which allows a lingering structure to be 'present "underneath"' the new structure. The fact

### 6.3 Electrophysiological and behavioral manifestations of coherence

that the authors scare-quote "underneath" suggests a subtle discomfort with the spatial implications of this metaphor, which are dissonant with the conventional conception. The lingering structure must be underneath the new one because objects cannot occupy the same space. But what is the nature of this new space that is underneath another space in which structures of objects can be "present"?

It is not the notion that interpretation involves parallel (i.e. simultaneous) activation of systems that is the problem, but rather, the notion that working memory is a space for objects. The problems are easily resolved when we see that our use of the term *working memory* refers to certain aspects of a state (or dimensions of a state space), rather objects occupying space. A working memory state can be defined in the same ϕ/e state space as the one in which production and interpretation trajectories are defined. A "lingering structure" is a set of activated cs-resonances, which by virtue of being in an active state have an increased likelihood of being integrated into a stable configuration. These same systems may also prevent newly activated systems from participating in a configuration or may destabilize other systems.

The o/el framework thus provides an alternative vocabulary that, because of its emphasis on the dynamics of systems and construction of state spaces, clarifies our conception of information, avoids anthropomorphization, and links our conceptual model of language more directly to behavioral observations. The disadvantage of the alternative vocabulary is that it is unfamiliar. The only way to change that is to practice using the vocabulary, and thereby explore its utility for conceptualizing phenomena. To that end, the next chapter examines several syntactic phenomena which have received much attention in the conventional perspective.

# **7 Syntactic phenomena**

In this chapter we apply the tools of the o/el framework to a variety of syntactic phenomena, such as ellipsis, anaphora, wh-expressions, and island patterns.1 We reject various object-metaphor conceptualizations of these phenomena – movement, copying, deletion, feature matching, etc. – but may use some terminology that evokes them for convenience. In most cases we pursue analyses from the perspective of production. However, we make the assumption that producers obtain a coherent trajectory prior to selectional production; hence we conflate producer and interpreter to some degree by conjecturing that utterance coherence is required for production. One can envision a parallel approach which pursues analyses from the perspective of interpretation; but due to our emphasis on potentially reiterative trajectories (i.e. utterance coherence), production-based and interpretation-based analyses may not be substantively different.

# **7.1 Ellipsis**

From a conventional perspective, ellipsis is commonly conceptualized as a phenomenon in which objects are "deleted" from a structure, often when those same objects are present elsewhere in the structure (Merchant 2001; 2005; 2013). For example, consider the utterance in (1). We might expect *Al drank* to be selected again in the second clause.

(1) Al drank coffee first and (Al drank) tea second.

1These phenomena are of course very complicated and hence the treatments presented here are necessarily incomplete. The goal is to illustrate the general applicability of the o/el framework, rather than establish a definitive understanding of the phenomena. Moreover, the analyses conducted are of coherence intuitions that are my own, and without further empirical work there is no guarantee that my intuitions correspond to intuitions which other speakers may have. I can only hope that there is no great disparity between my intutitions and those which are normal among native speakers. The reliance I have on *Al* and *Bo*, *drinks* and *eats*, and *coffee*, *tea*, and *granola*, is a potential problem as well, to the extent that proper names, simple/habitual tense-aspect ambiguity, and mass nouns could lead to abnormal coherence intuitions in various contexts.

### 7 Syntactic phenomena

The elided words in this example, and in general, are not necessarily a constituent in the conventional view. Although we can imagine any sequence of words being elided, not all possible ellipses are coherent. Here we construct an o/el understanding of ellipsis and develop analyses of why some ellipses are coherent and others are not.

# **7.1.1 Motoric vs. syntactic accounts**

With o/el conceptual tools, there are two types of accounts of ellipsis, one motoric and the other syntactic. This is also the case for conventional approaches. For several reasons, the syntactic account is preferable, but let's consider both approaches for the sake of argument.

For the motoric account, we imagine that cs-system trajectories are canonical: the cs-systems associated with elided words are in fact selected, but gm-systems in the g-domains of these cs-systems are not selected. This account is "motoric" because ellipsis is understood as the non-selection of gestural-motoric systems; it can be construed as m-gating applied to particular systems. In contrast, for the syntactic account, we imagine that cs-systems associated with the elided words are not selected.

To see how motoric and syntactic accounts differ, let's consider the gapping ellipsis in (12): *Al drank coffee first and tea second*, shown in Figure 7.1. In both accounts, [Al]{N} and [drank]{V} are promoted to selection and demoted, prior to epoch (e1). For the motoric account, at a later epoch (e2), [Al]{N} is once again promoted to selection level. However, the g-domain associated with this cs-system is not re-excited (or alternatively, is excited but does not reach selection-level). The same applies to [drank]V in the following epoch. In contrast, in the syntactic account [Al]{N} and [drank]{V} remain excited during the later epoch (e2) but are not re-promoted to selection level.

In both approaches, [Al]{N} and [drank]{V} persist in an above ground state and give rise to |Al drank tea| and |drank second| ϕ-configurations. The two approaches differ regarding whether the clausal e-reorganization of cs-systems is canonical (the motoric account) or selective (the syntactic account). The question is, do both possible types of ellipsis occur, or should we always prefer just one in our analyses? These two accounts relate to an old disagreement about whether non-constituent coordination is really coordination of constituents in deep structure, with the apparent non-constituent coordination being a consequence of surface deletion (Dalrymple et al. 1991; Merchant 2001; Sag et al. 1985).

(2) Al drank coffee first and (*Al drank* → Ø) *tea second*

Figure 7.1: Motoric vs. syntactic accounts of ellipsis.

One of the motivations for positing such deep structure is to serve semantic interpretation. The conventional paradigm requires objects to be "present" *somewhere*, so that meaning can be determined from structure. In the o/el framework, relational meaning experiences arise from attentionally focused (excited) cs-system ϕ-configurations, and hence the relevant systems must be above ground and ϕ-coupled. Importantly, selection-level excitation is not required for relational meaning, and this allows for a syntactic account in which systems can persist in an excited state and support ϕ-configurational meaning, without being selected.

# **7.1.2 Ellipsis in coordinative vs. subordinative reorganizations**

The syntactic account of ellipsis makes use of a selective reorganization operation associated with the transition from one clausal ϕ-configuration to another, in which only some excited systems are grounded. In particular, the grounded systems are only those which interfere with systems that are promoted from ground. One useful application of this approach is to account for coherence intuitions of ellipses in coordinate vs. subordinate clause structures. Consider the coherence contrast between the sentences in (3):

	- b. \*/? Al drank coffee, if Bo tea.

### 7 Syntactic phenomena

Why is ellipsis of the {V} system less coherent when in a subordinate clause than in a coordinate clause? The coherence contrast suggests that [drink]{V} cannot as readily form a ϕ-configuration with [Bo] and [tea] after a subordinate clause reorganization, compared to a coordinate clause reorganization. Because of this we infer that [drink]{V} in (3b) is more likely to be grounded in the epochs during which [Bo] and [tea] are excited than in in (3a). To account for the contrast, we hypothesize a distinction between reorganizations associated with coordinate and subordinate clauses: coordinating reorganizations typically allow for cs-systems to remain excited, subordinating reorganizations are more likely to ground all previously excited systems.

Specifically, in a coordinative reorganization, lexical cs-systems from the previous epoch can remain excited, if those systems do not interfere with a cs-system promoted from ground in the coordinative reorganization. Hence in the coordination trajectory in Figure 7.2, [drank]{V} remains excited after Ê4 , while [Al] and [coffee] are grounded. The reason [Al]{N} and [coffee]{N} are grounded in this reorganization is because they interfere with cs-systems [Bo]{N} and [tea]{N}. In contrast, Ê4 in the subordinative reorganization grounds all cs-systems, including [drank]{V}. Hence [Bo] and [tea] cannot participate in a ϕ-configuration with a {V} in (e4), thereby inducing non-coherence. Note that our analysis constructs just one [drink]{V} system, but we might also allow for an analysis in which [drink] and {V} systems are differentiated in parallel. Parallel c-/s- differentiations of this sort can be viewed as states which induce ellipsis, i.e. the non-selection of cs-systems which experience parallel c-/s- differentiation.

One aspect of the above analysis worth emphasizing is that we think of the coordinating conjunctions such as [and]{conj}, [but]{conj}, and [or]{conj} as systems which are specifically associated with promoting some other systems from ground in a coordinative reorganization. Hence when [Bo]{N} and [tea]{N} are promoted from ground in reorganization Ê4 , we imagine [and]{conj} to be activated and excited. In contrast, we analyze subordinators such as [if]{sub}, [when]{sub}, etc. as cs-systems which are activated in parallel with grounded cs-systems. This suggests a fundamental difference between coordination and subordination such that subordinators correspond to systems which are in ϕconfigurations with other systems (usually {V}), while coordinators are the manifestation of ungrounding promotion operations.

Furthermore, the reader should note that the non-coherence intuitions motivating the above analysis can be diminished if one "tries hard" to evoke the |Bo drank tea| configuration in the subordinative reorganization. Perhaps this effortful adjustment adapts the subordinative reorganization to be more like a coordinative one, i.e. one which maintains [drank]{V} above ground. Thus we infer

### 7.1 Ellipsis

Figure 7.2: Coordinative reorganization vs. subordinative reorganization.

that in the typical subordinative reorganization trajectory, excitation of a subordinate clause grounds all other systems in previously excited configurations, but this operation can be overridden via a mechanism which maintains some relevant systems in an excited state. This effortful excitation is a potential source of variability in coherence intuitions of ellipses (see Frazier & Clifton 2005; Phillips 2003; Phillips & Parker 2014 for examples of empirical variability).

The o/el conception of ellipsis avoids any concept of deletion or omission of objects in a structure. Ellipsis corresponds to a trajectory in which some cssystem(s) are not selected yet remain sufficiently excited to participate in an attended ϕ-configuration. Because subordinative reorganizations tend to ground previously excited systems, ellipsis in a subordinate clause is not coherent. There are, however, circumstances when previously grounded systems can be re-promoted from ground and thus participate in the ϕ-configuration of the subordinate clause.

One such circumstance involves the presence of an auxiliary s-system {Aux} in both the main and subordinate clauses. Consider the patterns in Table 7.1. Contrary to expectation, we observe that ellipsis in a subordinate clause is coherent, but only when an auxiliary verb is present in the subordinate clause, as in the pseudo-gapping and VP-ellipsis patterns (Johnson 2001; 2009; Merchant 2001).

The relevant difference between gapping/stripping and pseudo-gapping/VPellipsis is the excitation of an {Aux} system in the subordinate clause. This suggests that there is a mechanism for re-exciting a previously grounded cs-system,

### 7 Syntactic phenomena

Table 7.1: Four varieties of ellipsis in coordinate and subordinate clauses.

when that cs-system is coupled to another highly excited system. We call this *assisted persistence*. Hence we envision in the pseudo-gapping example of Figure 7.3(B) that promotion of {Aux}[will] by Ê5 allows for {V}[drink] to remain above-ground (i.e. the demotion of {V} is non-grounding). This allows for a coherent |Bo drink tea| ϕ-configuration. The assisted persistence mechanism may be related to the observation that [will]{Aux} and [drink]{V} could be analyzed as differentiated cs-systems, which are strongly coupled in association with both clauses. Note that ellipses with non-identical auxiliaries such as *Al will drink coffee, and Bo did tea* are much less coherent.

Figure 7.3: An auxiliary allows for a verb to persist in an excited state.

### 7.1 Ellipsis

The assisted persistence mechanism is highly constrained. {Aux} can allow both {V} and {−N} to persist across a clausal reorganization (4a), but the trajectory is somewhat less coherent if only {V} persists (4b). Coherence is strongly compromised when if only {−N} or {+N} are required to persist above ground, as in (4c) and (4d). This suggests that relative e-organization may be a factor in assisted persistence and that coherence intuitions will differ in languages with different fixed word orders.

	- b. (?)Al will drink coffee, if Bo will (drink) tea.
	- c. ?Al will drink coffee, if Bo will brew (coffee).
	- d. ?Al will drink coffee, if (Al) will brew coffee.

Another interesting aspect of the phenomenon is the influence of g-domain identity. When the {Aux} selection is associated with a contracted gm-organization in the subordinate clause, the elision trajectory is less coherent. This condition is exemplified by the coherence contrasts in (5). The ellipsis is only coherent in (5c) where the non-contracted auxiliary occurs.

	- b. ?Al will drink coffee, if Bo'll tea.
	- c. Al'll drink coffee, if Bo will (tea).

These patterns might suggest that gm-excitation plays a role in the assisted persistence mechanism, but there is an alternative interpretation. Note that a key difference in cs-organization between contracted and uncontracted forms of the auxiliary is whether {Aux} occupies a level of its own or is co-selected with other systems. As exemplified in Figure 7.4(A), when [will]{Aux} is selected independently from other lexical systems, [drink]{V} can persist in an excited state in the reorganization Ê5 . However, when [will]{Aux} is co-selected with [Al]{N} as in Figure 7.4(B), the reorganization grounds [drink]{V}.

Other types of s-systems than {Aux} can assist the persistence of cs-systems. Consider the complement clause elisions in (6). As expected, the elision is more coherent in the coordinated clause (6a) than the subordinated one (6b). However, the selection of the nonfinite clause s-system [to]{fin} in (6c) seems to facilitate a coherent interpretation. This suggests that [to]{fin} assists the persistence of systems associated with the elided complement clause. Nominal modifiers can assist persistence as well, as do quantifiers in utterances such as *Al drank two coffees, if Bo drank one*.

### 7 Syntactic phenomena

Figure 7.4: Assisted persistence from an auxiliary system is stronger when the auxiliary is independently selected.

	- b. ?Al was ordered to drink coffee when he refused (to drink coffee).
	- c. Al was ordered to drink coffee when he refused to.

By using the term *persistence*, we imply that the relevant system is excited before and after the clausal reorganization, and remains so throughout. In top example trajectory of Figure 7.5, [drink]{V} fails to be grounded by the subordinative reorganization Ê5 because [will]{Aux} is excited. Note that an alternative possibility shown in Figure 7.5 is that [drink]{V} is grounded by Ê5 , and is promoted from ground by a subsequent reorganization. Because this grounding-andpromotion analysis results in a noncoherent epoch (e5), we prefer the persistence analysis.

In the above analyses, we have constructed two [will]{Aux} systems by presupposing parallel differentiations of the c-system [will] and the s-system {Aux}. However, we did not represent parallel c-/s- differentiations for [drink]{V}. As mentioned above, the excitation persistence mechanism can be interpreted as a manifestation of parallel differentiation of [drink]{V}. In other words, we imagine that there are two [drink]{V} cs-systems which are highly overlapping and thus interact strongly. Ellipsis is often coherent precisely when parallel c-/s- differentiation of a lexical system occurs in association with different clauses. Parallel c-/s- differentiation can thus be seen as a state which induces non-selection of

Figure 7.5: Two possibilities for persistence: non-grounding reorganization and grounding with subsequent promotion.

excited systems. Subordinative reorganization can in this light be viewed to interfere with parallel c-/s- differentiation of lexical cs-systems, while assisted persistence – in the form of coupling with an {Aux} system – can stabilize parallel c-/s- differentiation.

# **7.1.3 Reiterative facilitation of persistent excitation**

The above analyses can be generalized to cases in which the elision of a system precedes the selection of that same system. We accomplish this by applying the persistent excitation analysis to a reiterative trajectory. The interactions of this more general analysis with the varieties of ellipsis above (gapping, stripping, VP ellipsis, pseudogapping, etc.) are somewhat complicated and intuitions can be difficult to assess. For simplicity, we consider only the object NP ellipsis in (7) (cf. Wilder 1997). The ellipsis in a coordinated clause (7a) seems to cohere more readily than examples (7b) and (7c), where one of the clauses is subordinate. The persistent excitation analysis developed above, with no further mechanism, predicts that none of the three trajectories should cohere because the non-selected cs-systems seem not to have been excited in any preceding epochs.

	- b. ? Al brews so Bo drinks coffee.
	- c. ? If Al brews, Bo drinks coffee.

### 7 Syntactic phenomena

However, recall that reiterative simulation creates periodic trajectories in which absolute notions of precedence become less tenable. To account for the coherence of (7a), we can imagine that the producer obtains a reiterative trajectory before selectional production. In the trajectory of Figure 7.6, (e0–e5) are reiterative and non-selectional. The key insight is that when the trajectory transitions to a selectional regime with reorganization Ê6 , [coffee]{N} has already been excited and can remain so. Thus the presence of a reiteration prior to selectional production allows for coherence of (e6) and (e7). What is more challenging to explain is the non-promotion of [coffee] in Ê8 ; this might be understood as an anticipatory reorganization of excitation for the ϕ-configuration of the second clause.

Figure 7.6: A reiterative trajectory before selectional production facilitates persistent excitation.

Why do the sentences with a subordinated clause in (7b) and (7c) fail to cohere as readily as the coordinated clauses in (7a)? Presumably the distinction between coordinative and subordinative reorganization applies to reiterative trajectories as well. To account for non-coherence of (7c), we suspect that the subordinative reorganization destabilizes coupling of [brews]{V} with [coffee]{N} because it grounds [coffee]{N} in the reiterative trajectory. To account for non-coherence of (7c), we could infer that initial organization, or organization of a main clause, also involves grounding demotions. Hence [coffee]{N} is not excited in epochs when [Al]{N} and [brews]{V} are excited, resulting in non-coherence.

The generalizations that emerge from the above analyses are as follows: only coordinative reorganizations allow unassisted persistence of excitation; subordinative and main-clause reorganizations ground previously excited systems; some other mechanism, such as assisted persistence, is required to maintain excitation of systems through a subordinative or main-clause reorganization.

# **7.1.4 Contextual excitation and ellipsis**

Another influence on coherence of trajectories with ellipsis is excitation of systems by discourse context. Contextually excited cs-systems which, despite not

### 7.1 Ellipsis

being selected in the same sentence, and perhaps never being selected at all, can participate in ϕ-configurations if they have above-ground excitation. Consider the answer ellipsis examples in (8):

(8) a. S1: Who drank coffee? S2: Al. b. S1: What did Al drink? S2: Coffee.

In these examples, cs-systems which were excited for S2 as an interpreter of S1 may not be promoted to selection level for S2 as a producer. Hence for the question response in (8a), [drank]{V} and [coffee]{N} are excited in the production trajectory for S2, but may not be selected. These systems nonetheless can participate in the |Al drank coffee| ϕ-configuration. As shown in Figure 7.7, S2 will couple the selected cs-system of the response to the relevant wh-system, which remains active in production epochs (e1–e3). In a sense, our analysis has the spirit of analyses in which answer fragments have "fully sentential structures" (Merchant 2005), but our conceptualization of structure here is radically different.

Figure 7.7: Ellipsis in a question response: cs-systems excited in the interpretation trajectory remain excited in the production trajectory of the response.

In the above analyses, we have established a viable set of analytic tools for understanding various aspects of the phenomenon of ellipsis. These tools include persistent excitation, assistance of persistent excitation through coupling to excited systems, and reiterative trajectories which precede selectional production. In combination with hypothesized differences in grounding propensities of coordinative vs. subordinative/main clause reorganizations, the analytic tools can explain a variety of ellipsis patterns. Further evidence of their utility comes from applying them to other phenomena, such as anaphora.

### 7 Syntactic phenomena

# **7.2 Anaphora**

From the conventional perspective, anaphora is the occurrence of an expression (syntactic object) whose interpretation depends on the presence of another object, and coreference is the more general circumstance in which two expressions refer to the same person or thing (Hankamer & Sag 1976; Huang 2000; Reinhart 1983; 2016; Safir 2004). In (9), anaphors and their coreferent expressions are indexed:

(9) Ali brews coffeej and hei drinks itj .

There are a number of sensible questions from the conventional perspective, such as whether there are structural constraints on coreference patterns and on the temporal ordering of coreferent expressions in sentences. From an o/el perspective, we reframe these questions, asking what conditions induce the selection of anaphors in production trajectories. The focus here is on nominal anaphora, with the presumption that the account can be extended to verbal anaphora.

# **7.2.1 Anaphoric systems**

Because of their unique behavior, we posit a new class of s-systems for anaphors, {pro}, and also a class of anaphoric c-systems, which we label generically as [pro]. As expected, these systems form cs-resonances, {pro} differentiates readily into {+pro} and {-pro}, and {pro} can be co-selected with a variety of grammatical s-systems, e.g. {person}, {number}, {gender}. The {pro} s-system is unlike {N} in that {ADJ} and {D} systems do not readily ϕ-couple with {pro} (i.e. \**the cold it*). The [pro] c-system is unusual in that it evokes a nonspecific meaning; this may explain why it does not couple with {Adj} or {D}. We hypothesize that in typical uses, the specificity of meaning experiences from ϕ-configurations with {pro} results from +ϕ coupling between {pro} and some other excited system. This system may be excited from contextual forces, may have been excited earlier in an utterance, or may be excited in a reiterative trajectory preceding selectional production.

Consider the utterance *he drinks it* and two possible initial configurations of production, shown in Figure 7.8. The state in (A), in which no lexical {N} systems are excited, cannot give rise to a coherent meaning experience. Instead we hypothesize an initial configuration such as (B), where each {pro} is coupled to an excited lexical s-system. These lexical systems are not promoted to selection during production. Another somewhat atypical characteristic of [pro]{pro} systems

### 7.2 Anaphora

is that their g-domains tend to vary as a function of co-selected grammatical systems. The set of co-selected grammatical s-systems determines the g-domain of [pro]{pro}, as represented in (B). To avoid clutter, we usually omit these grammatical systems from representations.

Figure 7.8: Pronominal systems are coupled to lexical systems.

The excitation of a {pro} system is an alternative and less direct mechanism for stabilizing a ϕ-configuration. For coherence to occur, each {pro} must be coupled to a lexical cs-system. An even stronger account posits that excitation of an {N} system always activates a corresponding {pro} system. For the trajectory of (10) shown in Figure 7.9, we could imagine that during epochs in which the first clause is attended (e.g. e1), {pro} systems coupled to {N}[Al] and {N}[coffee] are activated. In later epochs (e.g. e4) with attention on the second clause, those {PRO} systems are excited and are promoted to selection instead of [Al]{N} and [coffee]{N}. The lexical systems nonetheless remain above ground, another example of persistent excitation. Moreover, because coherence occurs with anaphors in a subordinated clause (e.g. *Al drinks coffee, if he brews it*), we infer that {pro} systems facilitate the persistence of excitation of the lexical system with which they are coupled. Thus the excitation of {pro} systems by Ê4 keeps [Al]{N} and [coffee]{N} above ground, which is another example of assisted persistence.

### (10) Al drinks coffee, and he brews it.

One of the interesting characteristics of {pro} systems is that there is evidently a bias to select them instead of lexical systems, but only when the relevant lexical system has already been selected. The bias is not an obligation, since productions can occur such as *Al drinks coffee, and Al brews coffee*. Nonetheless, an explanation for the {pro} bias is desirable. One possible mechanism to create a bias for

### 7 Syntactic phenomena

Figure 7.9: Pronominal systems assist in the persistence of lexical systems.

promotion of {PRO} rather than {N} may involve recent demotion of the conceptual and/or gestural systems associated with lexical cs-system. In other words, recently demoted systems are less amenable to be subsequently promoted.

Anaphora is similar to ellipsis, in that it occurs when parallel c-system and ssystem differentiation is required. Generally, we can view anaphora and ellipsis, along with direct reference and null pronominal reference, as different classes of trajectories for evoking a meaning experience. These are compared in Table 7.2.

Direct reference and ellipsis create relational meaning experiences from ϕ-configurations directly through coupling of lexical s-systems. In contrast, anaphora creates relational meaning more indirectly. For example, by coupling to both [Al]{N} and [drinks]{V}, {pro} indirectly brings about the ϕ-configuration |Al drinks coffee|. In direct reference and anaphora, the relevant cs-system which participates in the ϕ-configuration(s) is selected; in ellipsis, this cs-system is not selected. Given this taxonomy of reference, a logical possibility is a non-selected [pro]{pro} system giving rise to a ϕ-configuration indirectly. This could correspond to a null pronominal or big pro, as in *Al wants* pro *to drink coffee*.

# **7.2.2 Temporal ordering of anaphoric and lexical systems**

In some circumstances, an anaphor and its lexical antecedent can be selected in either temporal order, as shown by the example of backward anaphora in (11b)

7.2 Anaphora

Table 7.2: Classification of referential mechanisms.

below (cf. Kazanina et al. 2007; Reuland & Avrutin 2005). In conventional approaches, such examples violate a hypothesized principle requiring antecedents to "precede" anaphors in a structural sense, and hence necessitate a movement analysis (Chomsky 1993). Instead of moving object structures, we can understand such phenomena to be associated with a reiterative trajectory, just as we did for ellipses.

We imagine that the reiterative trajectory in Figure 7.10 (e0–e6) precedes selectional production of the utterance. Thus the lexical antecedent of the matrix clause can persist in an excited state when overt production of the subordinate clause occurs. The utterances (11a) and (11b) can be distinguished according to when, in the context of the reiteration, production transitions to a selectional regime. When the transition occurs in conjunction with a reorganization to (e0), sentence (11a) is produced; when the transition occurs with reorganization to (e3), sentence (11b) is produced. In this case, promotion of [it]{pro} assists the persistence of [coffee]{N}, which was excited in non-selectional epochs of the reiteration.

	- b. When Bo brews it, Al drinks coffee.

However, the coherence contrast between the examples in (12) suggests that reorganization to a main clause exerts a stronger grounding force on systems

### 7 Syntactic phenomena

Figure 7.10: Backward anaphora is possible when a reiterative trajectory precedes selectional production.

than reorganization to a subordinate or coordinated clause. When a production trajectory transitions to a selectional regime for a main clause, all systems are grounded, except those associated with the main clause. Hence [coffee]{N} is grounded during attention to the relevant ϕ-configuration in (12b), rendering the trajectory noncoherent. In the trajectory for (12b) in Figure 7.11, we show a reiteration of epochs (e0–e6). Note that the reorganization of attention to the main clause (Ê7 ) demotes [coffee]{N} to ground, and hence [coffee]{N} is not available when production subsequently transitions to a selectional regime. Of course, with some effort, [coffee]{N} can be promoted to an excited state in this transition, and we suspect that this accounts for variation in coherence intuitions.

	- b. ? Al drinks it, and/when Bo brews coffee.

From the perspective of interpretation, sentence (12b) may evoke an exophoric relation between [it]{PRO} and a contextually activated system. Because of the immediate organization bias, an interpretation trajectory may involve excitation of a lexical {N} system which is not selected in an utterance, and this would naturally interfere with the intended interpretation.

The analyses we have developed of anaphora and ellipsis are based on the idea that various characteristics of clausal reorganizations influence the propensity for lexical cs-systems to remain excited. For ellipsis we observed that persistence

7.2 Anaphora

Figure 7.11: Reorganization to a main clause grounds all unattended systems.

of an elided cs-system is assisted when the system is coupled to another aboveground system, such an {Aux} system. For anaphora, we interpret {pro} as an assisting system of this sort. In both cases, when a reiterative regime precedes a selectional one, the normal temporal relation of antecedent/dependent relations can be reversed. Moreover, the analyses indicate a hierarchy of reorganizations based on the propensity of the reorganization to ground a system that has a promoted competitor. Table 7.3 shows this hierarchy:

Table 7.3: Hierarchy of reorganizations based on grounding propensity.

The reorganization-grounding hierarchy is a key aspect of our analyses of ellipsis and anaphora patterns. It is important to recognize that such analyses are only necessary because we have rejected the assumption that systems associated with different clauses are equivalently co-present. This rejection is desirable because of differentiation interference, which derives from the microscale model of differentiation. Moreover, we show below that differentiation motivates a novel analysis of binding.

### 7 Syntactic phenomena

# **7.2.3 Binding theory**

In general the forces which influence whether an anaphoric {pro} or lexical system is promoted to selection level are not so strong that only one option is possible. Both anaphoric and direct reference options are available in many contexts, although re-selection of the lexical cs-system as in (13a) tends to sound somewhat overly formal compared to selection of the anaphor as in (13b):

	- b. Al likes coffee and Bo likes it.

The biasing forces for selection of {pro} over a lexical system are stronger when the coreference obtains between two systems that participate in a ϕ-configuration with the same lexical system, as in the examples below. The conventional approach to this phenomenon is to identify a structural pattern ("binding domain") in which coreference obligates the reflexive form (Chomsky 1982; 1993; Haegeman 1994; Reinhart 1976; Safir 2004). From an o/el perspective, no such structure exists and therefore an alternative analysis is needed. To that end, we observe that reflexives are strongly preferred in a fairly unique configuration, one in which a c-system and an s-system differentiate in parallel and the differentiated systems obtain a −ϕ relation. Following our earlier analysis of pronoun g-domains, we begin by assuming that reflexive forms (i.e. *myself*, *ourselves*, *yourself* …) are the g-domain of a [self]{pro} cs-system, i.e. that there is a [self] csystem which is a subclass of [pro], and that the g-domain of [self] is determined by co-selected grammatical s-systems for [person], [number], [gender], etc.

	- b. \* Ali likes himi .

Consider that there is a unique pattern of interference in the prototypical reflexive construction, in which a {V} is coupled to both a {+N} agent and a {−N} patient, and both of these {N} are coupled to the same c-system. We show this circumstance in Figure 7.12(A), where the following conditions are required: {pro} must be +ϕ coupled to an excited lexical system, here [Al]{−N}; {pro} must be −ϕ coupled to [likes]{V}; and [Al]{+N} must be +ϕ coupled with [likes]{V}. It follows from transitivity of coupling that the only way for such a configuration to be stable is for [Al] to differentiate such that there is a [Al]{+N} system and a [Al]{−N} system. In other words, the differentiated [Al] systems have a distal ϕ relation; we call this a *destructive c-differentiation*. States of destructive c-differentiation in particular are associated with strong preference for the reflexive form. The

### 7.2 Anaphora

trajectory of (15b) in Figure 7.12(B) shows that the destructive c-differentiation must apply to c-systems which are excited in the same epoch, i.e. simultaneously attended, in order to induce excitation of the [self] system.

	- b. Ali likes Bo, and Bo likes himi .

Figure 7.12: Reflexives are associated with destructive c-differentiation interference.

It is informative to consider a related utterance, *Al likes Al*, which is readily coherent in a contrastive context, e.g. *Al doesnt like Bo. Al doesnt like Cam. Al likes Al*. This also requires destructive c-differentiation of [Al] such that there are [Al]{+N} and [Al]{−N} systems, but [Al]{−N} is typically co-selected with a focus system [foc]{foc}. The fact that [foc] or [self] (which we now see as a special type of [pro]) are strongly biased to occur in the destructive c-differentiation context suggests that these systems may serve to stabilize a configuration which is otherwise unstable.

The relational meaning experience associated with destructive c-differentiation of {N} often takes on an additional flavor. For example, *Al likes himself* may have some idiomatic quality of meaning that differs from *Al likes Bo*, or *Al likes coffee*. The additional idiomatic quality is perhaps more obvious in examples like *Al knows himself, Al kicks himself*, or *Al pushes himself* – all of which induce idiosyncratic meaning experiences which are not readily analyzed as compositional.2 These special flavors of meaning are difficult to describe, but our conceptual model suggests that they involve alternative patterns of c-system excitation induced by co-excitation of reflexive [self] and a verbal cs-system.

2Of course, in the o/el framework there is no conventional notion of compositionality, because meaning experiences are not combined in the way that objects are combined.

### 7 Syntactic phenomena

To further analyze binding phenomena lets consider the examples in (16) where the reflexive form does not readily cohere. Initial configurations for each of these sentences are shown in Figure 7.13. One important aspect of the analysis is the hypothesis that {Poss} s-systems are similar to {P} systems in that {Poss} typically relates two systems, one of which {Poss} is +ϕ coupled with, the other it is −ϕ coupled with. In examples (B) and (C), we see that because of the hypothesized configurations for {Poss}, the [Al] c-differentiation is not destructive, i.e. the differentiated [Al] systems in fact interfere constructively. Hence the required conditions are not present for use of [self].

	- b. \* Al's friends like himselfi .
	- c. \* Al likes himself's friends.

Figure 7.13: The reflexive is not coherent in the absence of destructive c-differentiation.

The analysis of (B) and (C) cannot be extended to (A), where the [self] form is +ϕ coupled to {V}. To explain the noncoherence of (A) a different account is needed.This could involve a number of factors, such as the +ϕ relation of [self] to {V}, its status as clause-initial, and/or its selection before the lexical system [Al]{N} to which it is coupled. There are many additional complications in the analysis of self forms which we do not address in detail here (see König & Siemund 2000; Safir 2004). Logophoric and emphatic uses of self-forms as in *Al likes the picture of himself* and *Al, himself a coffee-drinker, eats granola* most likely involve a different cs-system than the one we posited above, and this system is not subject to the same constraints as [self]{pro}.

Although a more comprehensive analysis is still in order, it is reassuring that to conceptualize binding phenomena in the o/el framework, we did not need to 7.3 Wh-questions and islands

invent new mechanisms. Instead, the contexts in which self-forms are obligatory and prohibited correspond fairly well to a particular form of differentiation interference, which is predicted by our model whether or not self-forms are present in a given language. Furthermore, it appears that a general analysis of anaphora can be built upon the very same concepts of grounding vs. non-grounding reorganization that are generally useful in the o/el framework.

# **7.3 Wh-questions and islands**

In conventional approaches, a common analysis of question formation in many languages involves an object movement schema (Baker 1970; Cheng 1997; Chomsky 1965; Karttunen 1977). For example, the wh-question in (17a) is understood to be created by moving the wh-expression in (17b). The wh-expression in (17b) is in the same position where it would occur in the corresponding declarative utterance (17c):

	- b. Al drank what?
	- c. Al drank coffee.

Below we construct an o/el understanding of Wh question patterns based on excitation in pre-selectional production, similar to our earlier analysis of topicalization. We then extend the account to a variety of so-called island effects, circumstances in which wh-promotion does not readily occur.

# **7.3.1 Wh-systems and long-distance dependencies**

The first question to address is whether we should pursue an analysis that proliferates s-systems and/or c-systems, i.e. whether we construct {whN}, {whADV}, etc. and/or [wh-nominal], [wh-adverbial], etc. Observe that wh-forms such as *what*, *who*, *why*, *how*, *where*, etc., when used for questions, have distributions which are similar to those of a variety of s-systems and obtain identical ϕ-coupling relations to {V}. An analysis is possible that proliferates classes of ssystems for these expressions, such as {whN}, {whV}, {whADJ}, and {whADV}, but this proliferation is unnecessary. Instead, we view wh-expressions as the gdomains of a special class of c-systems, which we refer to as *wh-systems.* These wh-systems form cs-resonances with the lexical s-systems that we have already constructed. We thus propose the configurations in Figure 7.14 for the examples in (17).

### 7 Syntactic phenomena

Figure 7.14: Example configurations with [wh]{N} systems.

In support of this approach, we observe in Table 7.4 that not only does each lexical s-system have a corresponding wh-expression, but for some lexical s-system classes there are several different g-domains which are associated with different flavors of meaning (cf. the adverbials, as well as person vs. non-person {N}). The conceptual specificity of the g-domains supports the c-system subclass analysis, since in general we do not expect to construct classes of s-systems to accommodate detailed variation in meaning flavors.

Table 7.4: [Wh] c-systems and associated s-systems.

Wh-systems are hypothesized to have relatively weak interactions with the sensory-motor surroundings, compared to prototypical c-systems. Recall that prototypical c-systems, on the microscale, are distributed populations that interact with diverse sensory and motor systems. For example, [coffee] is associated with the smell of coffee, its taste, its temperature, what it looks like, the sound of it brewing, steam coming off of it, etc.; various episodic memories associated with coffee: brewing it in different contexts, buying it, spilling it, etc.; various mo-

### 7.3 Wh-questions and islands

tor memories: how to hold a cup of it, how to drink it, etc. Prototypical lexical csystems have many such associations, and we conceptualize these as interactions with sensory and motor systems. In contrast, we hypothesize that wh-systems lack strong interactions with the surroundings. Of course, wh-systems do not lack surroundings interactions entirely: semantic differences such as person/animate from non-person/non-animate (*who* vs. *what*) can differentiate wh-systems. But the semantic differentiation of wh-systems is evidently more generic.

Furthermore, we conjecture that the wh-system population sizes are relatively large and/or more distributed compared to prototypical lexical c-systems. One consequence of this is that there is more internal interference in a wh-system than in a prototypical c-system, and this makes prototypical c-systems likely to outcompete wh-systems for excited cs-resonances. We can also view wh-systems as super-populations, overlapping with large numbers of c-systems. For example, all nominal concepts (i.e. c-systems which couple to {N}) might share a [whN] subpopulation that couples to {N}. This implies that when a c-system such as [coffee] is activated, the c-system [what]{N} would also be activated, but [coffee] typically outcompetes [whN] for cs-resonance. When no specific c-systems (such as [coffee] or [tea]) experience strong surroundings forces, then perhaps the corresponding wh-system [whN] is more likely to become excited.

Another consequence of the population size/spread conjecture is that when wh-systems do form excited cs-systems, the e values of those systems will be relatively high. This provides a potential explanation for why wh-systems have a tendency to be promoted to selection-level in initial e-configurations: the relatively high e values of wh-systems augments the e value of the corresponding cs-system in the pre-stable phase of production. Relatedly, wh-systems are often co-selected with a {focus} s-system, i.e. [qestion]{focus}, which is similar to [contrast]{focus} and may further augment excitation.

The activation of a wh-system and [Q] (i.e. [qestion]) normally results in an initial configuration in which the wh-system is promoted to selection level through augmented excitation, as shown in Figure 7.15. However, promotion does not inevitably occur from augmented excitation, as shown by echo questions, i.e. *Al drank WHAT?* and Wh in-situ, i.e. *Who drank what?* Note that many conventional analyses require movement of in-situ wh-forms in a semantic representation (i.e. logical form), because the relevant meaning relations must be viewed as patterns of connection (see Reinhart 1998; Watanabe 1992).

Another question pattern to consider is one in which no particular wh-system is excited, i.e. yes/no questions as in Figure 7.16. In such cases, lexical cs-systems are selected and the meaning experience involves questioning a clausal set of ϕ-configurations. In the examples below, the |Al drank coffee| configuration is

### 7 Syntactic phenomena

Figure 7.15: Wh-systems are often promoted to selection level in initial configurations.

questioned. In this case there is no wh-system to promote, and promotion of {tense} with *do*-support occurs instead. The noncoherence of in situ utterances with {tense} promotion (i.e. \**Al did drink what?*) suggests that {tense} promotion is a consequence of promotion of [q]{focus} and/or promotion of [wh]{N}.

Figure 7.16: Questions without wh-systems.

Further support for the connection of {tense} promotion with [q]{focus} promotion comes from the non-coherence of {tense} promotion when the subject NP is questioned, as shown below in (18a) and (18b). In these utterances, neither [Q]{focus} nor [wh]{N} are promoted from augmented excitation – [wh]{N} already occupies the initial selection level because of learned ϕ-e mappings. Note that *do*-support for [tense] systems should be distinguished from emphatic *do* in *Al did drink coffee* and the corresponding question in (c).

	- b. \* Who did drink coffee?
	- c. Who DID drink coffee?

### 7.3 Wh-questions and islands

In the o/el conceptualization, wh-question patterns involve promotion of a whsystem in the pre-stable organization phase. Whether this promotion occurs is determined by the surroundings forces. The [Q]{focus} system we have posited can be interpreted as a manifestation of the relevant surroundings states. Moreover, from the coherence of (18c) and multiple-wh utterances such as *who drank what?* we infer that [Q]{focus} can occur at most once with each set of co-selected systems. This reinforces the notion that [Q]{focus} and [contrast]{focus} have a deep similarity, based on their pragmatic origins and manifested in their propensity to couple with the accentual s-system, {ˆ}. Recall that {ˆ} is special by virtue of its association with the selection level of an e-potential. One possibility we leave for future consideration is whether in some question trajectories [Q]{focus} is re-promoted to selection level with each re-organization; an analysis of this sort could account for the intonational patterns associated with yes/no questions and clausal contrast.

The o/el conception is not consistent with any object-metaphor conception in which word-objects move from one position to another. A conventional justification for a structural notion of movement involves the concept of a *trace* (a phonologically "empty" syntactic object, cf. Chomsky 1965), which could be interpreted in the o/el framework as a cs-system without a g-domain. To assess this, lets consider the non-coherence of the utterances in (19).

	- b. \* What did Al drink coffee?

How do we account for the non-coherence of (19b), where [what] and [coffee] c-systems are excited? We could stipulate that a [trace]{N} system is excited and coupled to {V}, as shown below in Figure 7.17(A). However, this is not necessary in the o/el framework. The non-coherence of (19b) follows straightforwardly from our configurational invariance hypotheses. A transitive {V} system such as [drink]{V} +ϕ couples to one agentive {N} system and −ϕ couples to one patientive {N} system. In the initial configuration shown in Figure 7.17(B), [coffee]{N} has no lexical {V} system to couple to (because [drink]{V} is already coupled with [what]{N}), and thus the epoch is non-coherent.

The trace account in Figure 7.17(A) is also problematic because e-levels are only organized for cs-systems with a g-domain. In all other analyses, cs-systems with no g-domain are co-organized with some cs-system which has a non-empty g-domain. This condition can be interpreted as a consequence of the accentuation hypothesis whereby each set of co-selected cs-systems can excite at most one accentual s-system: excitation of {ˆ} is viewed as a consequence of selection, rather than a syntactic-conceptual resonance. Furthermore, recall that in

### 7 Syntactic phenomena

Figure 7.17: Movement/trace analyses of questions are problematic.

languages with stress, {ˆ} manifests as a primary stress/accent in gm-organization. Because systems with empty g-domains (such as a hypothetical [trace]{N} system) cannot be stressed, the trace analysis shown above is untenable.