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Vaidya, C. J.

Publications and source records attributed to Vaidya, C. J..

2 recordsLinked to original sources

From cognitive abstraction to adaptive behavior: neural bases of concept learning in autistic adolescents

BACKGROUNDLearned knowledge does not consistently generalize to new contexts in autistic individuals, limiting potential for adapting to real-world demands. This challenge is hypothesized to stem from difficulties with forming abstract representations, potentially arising from perceptual processing that favors local details over the gestalt. We tested the prediction that generalization would be primarily based on exemplar-specific representations in autistic youth using computational modelling coupled with neuroimaging. METHODSSixty-four autistic adolescents without intellectual disability (69% males; ages 14-18 years) completed a category generalization task during functional magnetic resonance imaging at two time points. Computational models estimated abstract (prototype-based) and specific (exemplar-based) representations and underlying neural correlates. We further examined associations with adaptive functioning and moderation by autistic traits. RESULTSContrary to predictions, we observed a consistent prototype-dominant majority, a subgroup who generalized without consistent representational reliance, and a small minority who failed to acquire category structure. Prototypes were represented in bilateral ventromedial prefrontal cortex (VMPFC), inferior parietal lobule (IPL), right frontal pole, and right lateral occipital cortex, while exemplars were represented in bilateral cuneus. Better generalization predicted better real-world adaptive functioning. Moreover, greater prototype-related activation in left IPL predicted better adaptive functioning in participants with higher autistic traits. CONCLUSIONSThese findings challenge the prevailing view that concept learning in autism relies primarily on hyper-specific perceptual processing, identify meaningful variability in representational strategies, and reveal neural pathways through which abstract representation may support real-world adaptive behavior.

neuroscience↗

Precision inhibitory stimulation of individual-specific cortical hubs slows information processing in humans

Non-invasive brain stimulation (NIBS) is a promising treatment for psychiatric and neurologic conditions, but outcomes are variable across treated individuals. This variability may be due in part to uncertainty in the selection of the stimulation site - a challenge complicated further by the variable organization of individual human brains. In principle, precise targeting of individual-specific brain areas serving outsized roles in cognition could improve the efficacy of NIBS. Network theory predicts that the importance of a node in network can be inferred from its connections; as such, we hypothesized that targeting individual-specific \"hub\" brain areas with NIBS would impact cognition more than non-hub brain areas. We first demonstrate that the spatial positioning of hubs is variable across individuals, but highly-reproducible when mapped with sufficient per-individual rsfMRI data. We then tested our hypothesis in healthy individuals using a prospective, within-subject, double-blind design. We found that inhibiting a hub with NIBS disrupted information processing during working-memory to a greater extent than inhibiting a non-hub area of the same gyrus. Furthermore, inhibition of hubs linking specific control networks and sensorimotor systems was retrospectively found to be most impactful. Based on these findings, we propose that precise mapping of individual-specific brain network features could inform future interventions in patients.\n\nSIGNIFICANCE STATEMENTThe network organization of every persons brain is different, but non-invasive brain stimulation (NIBS) interventions do not take this variation into account. Here we demonstrate that the spatial positions of brain areas theoretically serving important roles in cognition, called hubs, differs across individual humans, but are stable within an individual upon repeated neuroimaging. We found that administering NIBS to these individual-specific hub brain areas impacted cognition more than stimulation of non-hub areas. This finding indicates that future NIBS interventions can target individual-specific, but cognitively-relevant features of human brains.

neuroscience↗