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bioRxiv · 10.1101/075465

State-dependent modulation of functional connectivity in early blind individuals

Maxime Pelland·Pierre Orban·Christian Dansereau·Franco Lepore·Pierre Bellec·Olivier Collignon
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Abstract

Resting-state functional connectivity (RSFC) studies have highlighted how visual experience influences the brains functional architecture. Reduced RSFC coupling between occipital (visual) and temporal (auditory) regions has been reliably observed in early blind individuals (EB) at rest. In contrast, task-dependent activation studies have repeatedly demonstrated enhanced co-activation and connectivity of occipital and temporal regions during auditory processing in EB. To investigate this apparent discrepancy, the functional coupling between temporal and occipital networks at rest was directly compared to that of an auditory task in both EB and sighted controls (SC). Functional brain clusters shared across groups and cognitive states (rest and auditory task) were defined. In EBs, we observed higher occipito-temporal correlations in activity during the task than at rest. The reverse pattern was observed in SC. We also observed higher temporal variability of occipito-temporal RSFC in EB suggesting that occipital regions in this population may play a role of multiple demand system. Our study reveals how the connectivity profile of sighted and early blind people is differentially influenced by their cognitive state, bridging the gap between previous task-dependent and RSFC studies. Our results also highlight how inferring group-differences in functional brain architecture solely based on resting-state acquisition has to be considered with caution.\n\nHighlightsO_LIOccipito-temporal functional connectivity is modified by cognitive states.\nC_LIO_LIThis modulation is different in blind and sighted individuals.\nC_LIO_LIBlind participants have higher occipito-temporal temporal variability at rest.\nC_LIO_LIThe group difference in variability at rest explains the differences in modulation.\nC_LIO_LIInferring group differences with resting-state data should be subject to caution.\nC_LI

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Maxime Pelland, Pierre Orban, Christian Dansereau, Franco Lepore, Pierre Bellec, Olivier Collignon. 2016-09-16. State-dependent modulation of functional connectivity in early blind individuals. https://doi.org/10.1101/075465

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