Discussion
autistic
Differences in sensory processing are core to ASD, and have been postulated to arise from alterations in excitation–inhibition balance [We then focused on the pre-deviant standards expected to be most affected by repetition suppression. We demonstrated, for the first time, that activating GABAWe further moved beyond group-level approaches to capture the extent to which an individual responded to modulation of the GABA system with arbaclofen as its sensitivity index. This index strongly correlated with that individual’s ASD symptomology measured by the total AQ score. Moreover, a single AQ question capturing subjective sensitivity to sounds (perception), is also strongly correlated with GABAergic response. Thus, more autistic characteristics, including auditory perceptual features, were associated with greater establishment of repetition suppression by arbaclofen. The correlation analyses were under-taken to understand if the extent of GABA function differences at the sensory processing level are related to the extent of autistic features. We interpret the correlation result as indicating that the direction and extent of arbaclofen-elicited (i.e. GABA-dependent) shift in sensory processing is associated with the extent of an individual’s autistic features. Indeed, the transition between a weakening and strengthening suppression in response to arbaclofen was observed at AQ score 26—the ‘cut-off’ for ASD. In other words, GABA