Mechanisms of the contextual interference effect in individuals poststroke. Stroke motor recovery: active neuromuscular stimulation and repetitive practice schedules Motor Task Variation Induces Structural Learning Independent learning of internal models for kinematic and dynamic control of reaching Dissociated Contextual Interference Effects in Children and Adults Multiple Motor Learning Experiences Enhance Motor Adaptability Contextual Interference Effects on the Acquisition and Retention of Fundamental Motor Skills Contextual interference in learning new patterns of bimanual coordination. Contextual interference effect on perceptual-cognitive skills training. Exploring the Dynamic Nature of Contextual Interference: Previous Experience Affects Current Practice But Not Learning Practice Schedule and Acquisition, Retention, and Transfer of a Throwing Task in 6-YR.-Old Children Effects of Contextual Interference and Age on Acquisition, Retention, and Transfer of Motor Skill Blocked and Random Practice Organization in the Learning of Rhythmic Dance Step Sequences Motor learning following unilateral stroke. Effects of Contextual Interference on Acquisition and Retention of Three Volleyball Skills High Levels of Contextual Interference Enhance Handwriting Skill Acquisition Learning of grasp control in children with hemiplegic cerebral palsy. Effects of Contextual Interference on Learning Technical Sports Skills Practice Variability and Transfer of a Racket Skill Effects of Cognitive Processes and Task Complexity on Acquisition, Retention, and Transfer of Motor Skills Contextual Interference Effects in Learning Volleyball Skills Does the Contextual Interference Effect Last over Extended Transfer Trials?
Although intermixing different motor learning tasks via r and om schedules enhances long-term retention compared with " blocked " schedules , the mechanism underlying this context ual interference effect has been unclear . Furthermore , previous studies have reported inconclusive results in individuals poststroke . We instructed participants to learn to produce three grip force patterns in either r and om or blocked schedules and measured the context ual interference effect by long-term forgetting : the change in performance between immediate and 24-h posttests . Nondisabled participants exhibited the context ual interference effect : no forgetting in the r and om condition but forgetting in the blocked condition . Participants at least 3 mo poststroke exhibited no forgetting in the r and om condition but marginal forgetting in the blocked condition . However , in participants poststroke , the integrity of visuospatial working memory modulated long-term retention after blocked schedule training : participants with poor visuospatial working memory exhibited little forgetting at 24 h. These counterintuitive results were predicted by a computational model of motor memory that contains a common fast process and multiple slow processes , which are competitively up date d by motor errors . In blocked schedules , the fast process quickly improved performance , therefore reducing error-driven up date of the slow processes and thus poor long-term retention . In r and om schedules , interferences in the fast process led to slower change in performance , therefore increasing error-driven up date of slow processes and thus good long-term retention . Increased forgetting rates in the fast process , as would be expected in individuals with visuospatial working memory deficits , led to small up date s of the fast process during blocked schedules and thus better long-term retention Objective : To investigate progress toward motor recovery in patients with chronic hemiparesis ( mean time since stroke 3.2 years ) , comparing different types of practice schedules . Design : To increase voluntary control of the upper extremity , active neuromuscular stimulation was administered during blocked and r and om practice schedules as patients performed three specific movements : wrist/finger extension , elbow joint extension , and shoulder joint abduction . Methods : 34 stroke subjects volunteered to participate and were r and omly assigned to one of three treatment groups : blocked practice ( the same movement was repetitively performed on successive trials ) combined with active neuromuscular stimulation ; r and om practice ( different movements on successive trials ) along with active stimulation ; or no active stimulation assistance control group . Subjects completed two days of 90 minute training for each of two weeks with at least 24 hours of rest between sessions . A session was three sets of 30 successful active neuromuscular stimulation trials with the three movements executed 10 times/set . Results : Mixed design analyses on three categories of behavioural measures indicated motor improvements for the blocked and r and om practice /stimulation groups in comparison with the control group during the post-test period , with a larger number of blocks moved , faster premotor and motor reaction times , and less variability in the sustained muscular contraction task . Conclusions : Upper extremity rehabilitation intervention of active stimulation and blocked practice performed as well as stimulation/r and om practice . Moreover , these purpose ful voluntary movement findings support and extend sensorimotor integration theory to both practice schedules Summary When we have learned a motor skill , such as cycling or ice-skating , we can rapidly generalize to novel tasks , such as motorcycling or rollerblading [ 1–8 ] . Such facilitation of learning could arise through two distinct mechanisms by which the motor system might adjust its control parameters . First , fast learning could simply be a consequence of the proximity of the original and final setting s of the control parameters . Second , by structural learning [ 9–14 ] , the motor system could constrain the parameter adjustments to conform to the control parameters ' covariance structure . Thus , facilitation of learning would rely on the novel task parameters ' lying on the structure of a lower-dimensional subspace that can be explored more efficiently . To test between these two hypotheses , we exposed subjects to r and omly varying visuomotor tasks of fixed structure . Although such r and omly varying tasks are thought to prevent learning , we show that when subsequently presented with novel tasks , subjects exhibit three key features of structural learning : facilitated learning of tasks with the same structure , strong reduction in interference normally observed when switching between tasks that require opposite control strategies , and preferential exploration along the learned structure . These results suggest that skill generalization relies on task variation and structural learning Psychophysical studies of reaching movements suggest that h and kinematics are learned from errors in extent and direction in an extrinsic coordinate system , whereas dynamics are learned from proprioceptive errors in an intrinsic coordinate system . We examined consolidation and interference to determine if these two forms of learning were independent . Learning and consolidation of two novel transformations , a rotated spatial reference frame and altered intersegmental dynamics , did not interfere with each other and consoli date d in parallel . Thus separate kinematic and dynamic models were constructed simultaneously based on errors computed in different coordinate frames , and possibly , in different sensory modalities , using separate working-memory systems . These results suggest that computational approaches to motor learning should include two separate performance errors rather than one 24 7-yr.-old children and 24 university-age adults  practice d a ballistic aim ing task under either low context ual interference ( blocked practice ) or high context ual interference ( r and om practice ) . All subjects performed 90 acquisition trials , followed by 20 transfer trials and 15 retention trials . Similar to previous findings , the adults performed the acquisition trials better under blocked than under r and om conditions , yet performed the retention and transfer tests better after r and om than blocked practice . No differences in acquisition were found between blocked and r and om practice conditions for the children ; nevertheless , the r and om group performed the retention and transfer tests better than the blocked group . The results are discussed in relation to applied and theoretical issues of context ual interference Traditional motor learning theory emphasizes that skill learning is specific to the context and task performed . Recent data suggest , however , that subjects exposed to a variety of motor learning paradigms may be able to acquire general , transferable knowledge about skill learning processes . I tested this idea by having subjects learn five different motor tasks  , three that were similar to each other and two that were not related . A group of experimental subjects first performed a joystick- aim ing task requiring adaptation to three different visuomotor rotations , with a return to the null conditions between each exposure . They then performed the same joystick- aim ing task but had to adapt to a change in display gain instead of rotation . Lastly , the subjects used the joystick aim ing task to learn a repeating sequence of movements . Two groups of control subjects performed the same number of trials , but learned only the gain change or the movement sequence . Experimental subjects showed generalization of learning across the three visuomotor rotations . Experimental subjects also exhibited transfer of learning ability to the gain change and the movement sequence , result ing in faster learning than that seen in the control subjects . However , transient perturbations affected the movements of the experimental subjects to a greater extent than those of the control subjects . These data demonstrate that humans can acquire a general enhancement in motor skill learning capacity through experience , but it comes with a cost . Although movement becomes more adaptable following multiple learning experiences , it also becomes less stable to external perturbation This study was design ed to examine the effect of three practice models ( repetitions , r and om , and combined ) on the acquisition and retention of fundamental motor skills .  54 girls in Grade 4 were r and omly assigned to the three different practice groups who practice d three skills of ball rolling , racket striking , and ball kicking . All subjects received pretests , posttests , and a 3-wk . retention test . Performance was significantly improved during practice in the three groups for the three skills . The repetitions group performed better than the other two groups at the end of practice . The context ual interference effect in retention was only shown for the racket-striking skill , in which the r and om group was significantly better than the repetitions and the combined groups . An attempt was made to attribute that specific result to the special characteristics of the striking skill in this study as an open skill with which subjects had a previous experience Two experiments are reported in which the question of whether or not context ual interference effects are found in motor tasks that require the acquisition of new coordination patterns was examined . Participants ( N = 18 , Experiment 1 ; N = 12 , Experiment 2 )  practice d 3 novel bimanual patterns ( 45 degrees , 90 degrees , and 135 degrees relative phase ) in either a r and om or a blocked order . No statistically significant acquisition or retention differences between groups were found when all 3 patterns were practice d on each of 2 days ( Experiment 1 ) . When the blocked group practice d 1 pattern on each of 3 acquisition days ( Experiment 2 ) , however , typical context ual interference effects were found : The blocked group performed better than the r and om group in practice , but the r and om group performed better than the blocked group in a delayed ( by I week ) retention test . The experiments revealed that context ual interference effects can arise in motor tasks that require the acquisition of new coordination patterns and are not limited to tasks involving novel scaling of a previously existing pattern INTRODUCTION Context ual interference ( CI ) effect predicts that a r and om order of practice for multiple skills is superior for learning compared to a blocked order . We report a novel attempt to examine the CI effect during acquisition and transfer of anticipatory judgments from simulation training to an applied sport situation . METHOD Participants were required to anticipate tennis shots under either a r and om practice schedule or a blocked practice schedule .  Response accuracy was recorded for both groups in pretest , during acquisition , and on a 7-d retention test . Transfer of learning was assessed through a field-based tennis protocol that attempted to assess performance in an applied sport setting . RESULTS The r and om practice group had significantly higher response accuracy scores on the 7-d laboratory retention test compared to the blocked group . Moreover , during the transfer of anticipatory judgments to an applied sport situation , the decision times of the r and om practice group were significantly lower compared to the blocked group . CONCLUSION The CI effect extends to the training of anticipatory judgments through simulation techniques . Furthermore , we demonstrate for the first time that the CI effect increases transfer of learning from simulation training to an applied sport task , highlighting the importance of using appropriate practice schedules during simulation training ABSTRACT There is evidence that the learning benefits of context ual interference ( CI ) are moderated by experience , yet we do not know if these experiences are related to specific practice with r and om schedules . In two experiments , CI practice schedule was manipulated on Day 1 . We evaluated its impact on 3 new tasks on Day 2 ; in the same or different practice schedule ( Experiment 1 ) or when participants chose their practice ( Experiment 2 ) . Typical CI effects were observed for both sets of tasks , although on Day 2 , there were no longer any costs from r and om practice . Previous practice affected how practice was scheduled . The prior r and om group switched more than the prior blocked group . Although switching was related to retention , overall the groups did not differ . Therefore , specific experiences with a method of practice influence later choices about how to practice , performance in practice , but not necessarily what is retained Earlier studies have raised questions about the usefulness of variable and r and om practice in learning motor tasks so this study was design ed to investigate the effects of context ual interference in young children , and specifically to evaluate the effectiveness of variable or r and om practice structure in 6-yr.-old boys and girls . Participants on a variable practice schedule showed better performances than those on a blocked schedule . The differences between the two groups were significant in the acquisition , retention , and transfer phases . These results support the hypothesis that context ual interference enhances skill learning . Because the study involved groups of young children in the setting of their normally scheduled physical education class , the practical applications of the results are evident This experiment was design ed to Investigate the varying conditions of context ual interference within three age groups . 40 5-yr.-olds , 40 7-yr.-olds , and 40 11-yr.-olds practice d the task of throwing beanbags under either low context ual interference ( blocked practice ) , high context ual interference ( r and om practice ) , or medium context ual interference ( combined practice ) . All subjects performed 30 acquisition trials , 12 retention trials and 6 transfer trials . Analysis indicated that only the 7-yr.-old subjects differed in their performance in the various practice groups . As hypothesized and suggested by developmental theories , the combined and blocked practice groups acquired the task better . On the other h and , the 5- and 11-yr.-olds did not differ in performance in the different practice groups . Whether this is associated with difficulty of the task or the length of practice can be assessed in further study . Context ual interference in different age groups needs further investigation This study investigated the role played by Blocked ( low context ual interference ) and R and om ( high context ual interference ) schedules in the acquisition of rhythmic footstep sequences by adolescent females ( N = 40 , M age = 15.8 yr . , SD = 1.3 ) . After a baseline assessment ( T0 ) , motor learning was assessed after six sessions ( T1 ) in terms of the participants ' ability to reproduce the step sequences using visual and auditory guidance . A retention test ( T2 ) also occurred 21 days after T1 . Analysis of variance yielded significant main effects of group , test , and an interaction . Both groups improved performance from T0 to T1 , but the Blocked schedule group outperformed the R and om schedule group at T2 . Significant group differences were not observed at T2 . The R and om schedule group 's performance did not significantly change from T1 to T2 , and the Blocked schedule group 's performance significantly decreased . Apparently , the learning of rhythmic footstep dance sequences was not influenced by practice organization OBJECTIVE To determine the effect of different motor learning schedules on stroke patients '  rate of acquisition and retention of a functional movement sequence using the hemiparetic upper limb . DESIGN R and omized controlled group study using a retention design with two retention trials . SETTING Outpatient neurorehabilitation clinic . PATIENTS Twenty-four patients with chronic hemiparesis secondary to a single unilateral cerebral stroke without evidence of severe cognitive or language impairment . MAIN OUTCOME MEASURE The primary hypothesis was that hemiparetic motor learning that occurred under conditions of context ual interference ( ie , r and om practice ) would be retained better than learning that occurred under conditions of repetitive drill ( blocked practice ) . RESULTS A significant difference was found among the three groups ( ie , r and om- practice , blocked- practice , control ) on both the first retention measure ( chi 2 = 13.50 , p < .01 ) and the second retention measure ( chi 2 = 12.59 , p < .01 ) . More importantly , a significant difference was found between the r and om- practice and blocked- practice groups on both the first retention measure ( U = 68.5 , p < .01 ) and the second retention measure ( U = 62.0 , p = .05 ) . CONCLUSIONS Findings provide empirical evidence to support the contention that r and om practice is more effective than blocked practice , with respect to retention over time , when hemiparetic stroke patients attempt to learn functional motor skills Manipulating the organization of practice conditions , through context ual interference , was identified as a method to promote motor skill acquisition by Brady in 1998 . The generalizability of this learning effect is question able and the amount of repetition versus the amount of change in task presentation requires investigation . The purpose of this study was to explore explanations for the performance of learners practicing the AAHPERD volleyball skills test when the change in task presentation varied . High school students were r and omly assigned to blocked , r and om , and r and om-blocked practice groups . While all groups significantly improved all skills during acquisition , there was no support for the context ual interference effect . Potential explanations might be dependent upon the learners ' skill and the complexity of the task to be learned . Further research is warranted examining context ual interference effect on practice organization at levels of difficulty appropriate to facilitate cognitive processing of task-related information The authors conducted 3 experiments to examine whether introducing high levels of context ual interference is useful in h and writing skill acquisition . For all experiments , elementary school students ( Ns = 44 , 50 , and 78 , respectively ) were r and omly assigned to 1 of 2 practice schedules — blocked or r and om practice —in the acquisition phase . In the blocked condition , each of 3 letters ( h , a , and y ) or ( in Experiment 1 ) symbols was h and written 24 times consecutively . In the r and om condition , each letter ( or symbol ) was practice d 24 times , but in an intermixed , un systematic sequence . Overall , the results showed that the r and om practice schedule leads to enhanced retention and transfer performance of h and writing skill acquisition This study examined whether children with hemiplegic cerebral palsy ( CP ) have anticipatory control of fingertip forces during lifts of familiar objects , and what type of practice ( blocked or r and om ) best enhances the retention of anticipatory control during lifts of novel objects . Eighteen children with hemiplegic CP ( 7 females , 11 males ; 7 to 14 years of age , mean age 10 years , SD 1.8 ) and 18 age-matched typically developing children ( 8 males , 10 females ; mean age 10.4 years , SD 1.7 ) participated in the study . In the first experiment the children lifted familiar objects of various weights and sizes five times each , while the vertical lifting ( load ) force was measured . Most participants demonstrated higher rates of load force increase for heavier ( and larger ) objects already during the first lift , indicating anticipatory control . Furthermore , the load force rates generally were similar across the five lifts for each object , suggesting that they had stable representations of the objects ' properties . In the second experiment children lifted three novel objects varying in weight ( but identical in volume ) 27 times each , in either a blocked or a r and om order , followed by nine immediate and nine delayed ( 24 hours ) retention trials . Blocked practice result ed in greater differentiation of the force rates between objects during acquisition than did r and om practice . Both practice schedules result ed in similar retention . These findings suggest that children with hemiplegic CP have a priori internal representations used for anticipatory force scaling with familiar objects . Furthermore , the results indicate that these children can form and retain internal representations of novel objects for anticipatory control , irrespective of the type of practice schedule employed . Thus , clinical ly based practice sessions that incorporate lifts with novel objects may enhance anticipatory force scaling and related prehensile function in children with hemiplegic CP The effects of context ual interference on  learning skills of volleyball ( volley , bump , serve ) are influenced by the scheduling of actual practice sessions : the activities can be proposed in a repetitive practice schedule ( blocked practice ) by continuously repeating the same task ( low interference ) or in r and om practice schedules by performing more tasks or variations of one same activity ( high interference ) . High context ual interference , even though causing immediate limited performance , leads to superior performance on retention and transfer tests .  Four experimental groups ( 13 students each ) were placed in conditions of r and om , blocked , serial , and serial with high interference practice for 8 meetings ( 2 tests and 6 practice ) . Analysis yielded significant differences among the groups on a transfer test ( long transfer ) for the serve , so results in this instructional setting are partially in line with those generally found in laboratory experiments This study used a foreh and hitting task to explore the effect of racket variability on ‘ out of range ’ transfer .  48 11-yr.-old girls were r and omly assigned to four treatment groups of R and om Variability , Blocked Variability , Specific , and Control . The experimental groups had 32 trials for 4 successive days after which all groups were tested on 4 transfer conditions . Retention tests were given after 1 , 4 , and 8 days and the data were examined for treatment , range , and occasion effects . Analysis showed the superiority of practice over no practice  , variable over specific practice  , and r and om over blocked variability for transfer with two ‘ out of range ’ dimensions . Accuracy decayed between the transfer tests . These results are consistent with schema theory , and it is recommended that physical education teachers should focus variable practice on task dimensions that are new to their classes This experiment was design ed to investigate the effect of cognitive problem-solving operations ( termed context ual interference ) and complexity of tasks on the acquisition retention and transfer of motor skills .  Ninety-six children , ages 7.5–9.5 practised the task of throwing beanbags under either low context ual interference ( blocked practice ) , high context ual interference ( r and om practice ) or medium context ual interference ( combined practice ) . Half of the participants acquired a complex task and the other half a simple task . All participants performed 30 acquisition trials , 9 retention trials and 4 transfer trials . Results indicated that participants who practised in the blocked practice group did not differ in their performance whether they acquired complex or simple tasks . On the other h and , participants from the r and om and combined practice groups who acquired simple tasks performed better than those who acquired complex tasks . These findings support the hypothesis that there is a limit to the interference during practice that will benefit retention and transfer , thus creating the context ual interference effect . It seems that the complex-task condition combined with r and om or combined practice schedule increased the difficulty of acquisition , possibly impeding the cognitive processing during acquisition , thus impairing the learning process The aim of this study was to examine the context ual interference effect on learning three volleyball skills .  Participants were 26 novice female volleyball players ( M age = 12.4 yr . , SD = 1.2 ) . They were assigned into two groups , Low Interference ( n = 13 ) and High Interference ( n = 13 ) . Two practice schedules were used : blocked ( Low Interference ) and r and om ( High Interference ) . The training period lasted for 10 weeks and included 2 training sessions of 75 min . each per week . The pretest was performed before the first training session , the posttest was performed after the completion of the last training period , and the retention test was performed two weeks after the posttest . A 2 ( Groups ) × 3 ( Measurement Periods ) analysis of variance with repeated measures indicated significant improvement in performance between pre- and posttests for both High Interference and Low Interference groups for the three skills included in this study . There was no significant main effect of group or interaction effect of group and measure . These findings suggest that either blocked or r and om practice could be effectively used in learning of volleyball skills by unskilled children The context ual interference effect ( r and om practice yields better transfer and retention compared to blocked practice ) detected in a study of 24 boys and 33 girls r and omly selected ( M age = 10.5 yr . , SD = .6 ) performing a linear positioning motor task seemed to dissipate in extended transfer trials
AIM We aim ed to identify and evaluate the quality and evidence of the motor learning literature about intervention studies regarding the context ual interference ( CI ) effect ( blocked vs. r and om practice order ) in children with brain lesions and typically developing ( TD ) children .