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bioRxiv · 10.1101/2022.09.23.509144

Tug-of-peace: Visual Rivalry and Atypical Visual Motion Processing in MECP2 Duplication Syndrome of Autism

Abstract

Extracting common patterns of neural circuit computations in the autism spectrum and confirming them as a cause of specific core traits of autism is the first step towards identifying cell- and circuit-level targets for effective clinical intervention. Studies in human subjects with autism have identified functional links and common anatomical substrates between core restricted behavioral repertoire, cognitive rigidity, and over-stability of visual percepts during visual rivalry. To be able to study these processes with single-cell precision and comprehensive neuronal population coverage, we developed the visual bi-stable perception paradigm for mice. Our task is based on plaid patterns consisting of two transparent gratings drifting at an angle of 120{degrees} relative to each other. This results in spontaneous reversals of the perception between local component motion (motion of the plaid perceived as two separate moving grating components) and integrated global pattern motion (motion of the plaid perceived as a fused moving texture). Furthermore, this robust paradigm does not depend on the explicit report of the mouse, since the direction of the optokinetic nystagmus (OKN, rapid eye movements driven by either pattern or component motion) is used to infer the dominant percept. Using this paradigm, we found that the rate of perceptual reversals between global and local motion interpretations of the stimulus is reduced in the MECP2 duplication mouse model of autism. Moreover, the stability of local motion percepts is greatly increased in MECP2 duplication mice at the expense of global motion percepts. Thus, our model reproduces a subclass of the core features in human autism (reduced rate of visual rivalry and atypical perception of visual motion). This further offers a well-controlled approach for dissecting neuronal circuits underlying these core features.

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BibTeXRIS

Bogatova, D., Smirnakis, S., Palagina, G.. 2022-09-26. Tug-of-peace: Visual Rivalry and Atypical Visual Motion Processing in MECP2 Duplication Syndrome of Autism. https://doi.org/10.1101/2022.09.23.509144

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