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Atypical sensory processing one of the more ubiquitous symptoms in autism spectrum disorder, the exact nature of these sensory issues remains unclear, with different studies showing either enhanced or deficient sensory processing. Using a well-established continuous free-recall task that assesses visual working memory, the current study provides novel evidence reconciling these apparently discrepant findings by showing both enhanced and impaired sensory processing in the same individuals on distinct aspects of the same task and stimuli. Autistic children exhibited perceptual advantages in both likelihood of recall and recall precision relative to their typically-developed peers. When autistic children did make errors, however, they showed a higher probability of erroneously binding a given colour with the incorrect spatial location. These data indicate that although the initial perceptual representations of sensory inputs were maintained with enhanced fidelity, the subsequent cognitive process of binding multiple features of sensory information into one percept was impaired. These data align with neural-architecture models for feature binding in visual working memory, suggesting that atypical population-level neural noise in the report dimension (colour) and cue dimension (spatial location) may drive both the increase in probability of recall and precision of colour recall as well as the increase in proportion of binding errors, respectively. These changes are likely to impact core symptomatology associated with autism, as perceptual binding and working memory play significant roles in higher-order tasks, such as communication.

Visual working memory (VWM) involves the encoding and maintenance of visual information over time, with the requirement that object features be accurately bound to spatial locations. We and others have shown that damage to the right hemisphere leads to impaired spatial working memory. Here, we test the notion that right brain damage (RBD) may have consequences for domain general VWM. We had eight RBD patients and a group of healthy control participants perform a VWM task under different loads (1 to 3 items to recall) and spatial competition (high vs. low). All participants were asked to remember the colour of target items presented on the right side of space. Patients showed impaired encoding of information evident in poor precision of memory representations and increased guessing rates even at a set size of only one item. Our data suggests that VWM capacity is severely limited following RBD. Although five of the eight patients presented with neglect, it is not clear whether this deficit in VWM is unique to the syndrome. We suggest that future work should directly pit attention and VWM demands against one another in the same patients to determine whether the confluence of deficits in these domains is the critical determinant of the neglect syndrome. Regardless of the implications for the neglect syndrome, however, our data show that VWM deficits in RBD patients extend into non-spatial feature space.

We examined whether the selection mechanisms committed to the suppression of ignored stimuli can be modified by experience to produce a sustained, rather than transient, change in behavior. Subjects repeatedly ignored the shape of stimuli, while attending to their color. On subsequent attention to shape, there was a robust and sustained decrement in performance that was selective to when shape was ignored across multiple-color-target contexts, relative to a single-color-target context. Thus, amount of time ignored was not sufficient to induce a sustained performance decrement. Moreover, in this group, individual differences in initial color target selection were associated with the subsequent performance decrement when attending to previously ignored stimuli. Accompanying this sustained decrement in performance was a transfer in the locus of suppression from an exemplar (e.g., a circle) to a feature (i.e., shape) level of representation. These data suggest that learning can influence attentional selection by sustained attentional suppression of ignored stimuli.

How and what we attend to is foundational in determining the content of our experience, thus differences in attention contribute significantly to how we perceive the world, learn, and develop. Personality also plays a role in constraining how we learn to perceive the world and it is conceivable that some facets of personality interact with visual attention; however, the relationship between these two constitutional aspects of psychology remains unclear. To address this interplay between cognition and personality, we looked at how the Big Five personality traits relate to the spatial scope of attention, as indexed by the spatial distribution of Inhibition of Return (IOR). IOR is marked by a decrement in reaction time when a target appears at a cued location, more than 200 ms after that cue. As the cue/target distance increases there is a release from inhibition, providing a measure of the spatial distribution of IOR and reflecting the spatial scope of attention. The results presented here show personality does predict the distribution of IOR. Specifically, higher trait Openness is associated with a broader distribution of IOR and attention. This finding suggests there is an intimate connection between personality, particularly Openness, and the spatial allocation of attention.

If some of the distractors in a visual search task are previewed prior to the presentation of the remaining distractors and the target, search time is reduced relative to when all of the items are displayed simultaneously. Here, we tested whether the ability to preferentially search new items during such a preview search is limited. We confirmed previous studies: The proportion of fixations on old items was significantly less than chance. However, the probability of fixating old locations was negatively affected by increasing the number of previewed distractors, suggesting that inhibition is limited to a small number of old items. Furthermore, the ability to inhibit old locations was limited to the first four fixations, indicating that by the fifth fixation, the resources required to sustain inhibition had been depleted. Together, these findings suggest that inhibition of old items in a preview search is a top-down mediated process dependent on capacity-limited cognitive resources.