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bioRxiv · 10.1101/2024.04.03.587978

Saccadic compression of time as a marker for Developmental Dyslexia

Domenici, N.·Tonelli, A.·Ponente, C.·Gori, M.
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Abstract

About 10% of the worlds population is dyslexic, experiencing reading impairments unrelated to cognitive deterioration. Due to its impact, identifying the mechanisms subtending dyslexia is paramount. However, while most research focused on the eye movements phenomenology, none investigated their perceptual, transient consequences. In fact, it has been shown that rapid eye movements (i.e., saccades) are accompanied by temporary distortions of space and time. Such distortions have been linked to the receptive fields predictive remapping, which anticipates the movement and compensates for the gazes displacement. Here, we demonstrate that dyslexic children show reduced flexibility in modulating temporal information around the saccadic onset. Moreover, accuracy oscillations within the delta band, phase-locked to the saccades onset, preceded transient temporal compression in typical readers. Conversely, no oscillatory behavior was observed in dyslexic participants, suggesting that the absence of transient temporal distortions originated from the mismatch between the anticipatory remapping and the saccadic onset.

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Domenici, N., Tonelli, A., Ponente, C., Gori, M.. 2024-04-04. Saccadic compression of time as a marker for Developmental Dyslexia. https://doi.org/10.1101/2024.04.03.587978

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