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bioRxiv · 10.1101/2020.05.08.077289

Connectome and microcircuit models implicate atypical subcortico-cortical interactions in autism pathophysiology

Abstract

AO_SCPLOWBSTRACTC_SCPLOWBoth macroscale connectome miswiring and microcircuit anomalies have been suggested to play a role in the pathophysiology of autism. However, an overarching framework that consolidates these macro and microscale perspectives of the condition is lacking. Here, we combined connectome-wide manifold learning and biophysical simulation models to understand associations between global network perturbations and microcircuit dysfunctions in autism. Our analysis established that autism showed significant differences in structural connectome organization relative to neurotypical controls, with strong effects in low-level somatosensory regions and moderate effects in high-level association cortices. Computational models revealed that the degree of macroscale anomalies was related to atypical increases of subcortical inputs into cortical microcircuits, especially in sensory and motor areas. Transcriptomic decoding and developmental gene enrichment analyses provided biological context and pointed to genes expressed in cortical and thalamic areas during childhood and adolescence. Supervised machine learning showed the macroscale perturbations predicted socio-cognitive symptoms and repetitive behaviors. Our analyses provide convergent support that atypical subcortico-cortical interactions may contribute to both microcircuit and macroscale connectome anomalies in autism.

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Park, B.-y., Hong, S.-J., Valk, S. L., Paquola, C., Benkarim, O., Bethlehem, R. A. I., Di Martino, A., Milham, M., Gozzi, A., Yeo, B. T. T., Smallwood, J., Bernhardt, B.. 2020-05-10. Connectome and microcircuit models implicate atypical subcortico-cortical interactions in autism pathophysiology. https://doi.org/10.1101/2020.05.08.077289

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