Auditory features modelling demonstrates sound envelope representation in striate cortex

Published: March 29, 2021, 1:03 a.m.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.04.15.043174v1?rss=1 Authors: Martinelli, A., Handjaras, G., Betta, M., Leo, A., Cecchetti, L., Pietrini, P., Ricciardi, E., Bottari, D. Abstract: Primary visual cortex is no longer considered exclusively visual in its function. Proofs that its activity plays a role in multisensory processes have accrued. Here we provide evidence that, in absence of retinal input, V1 maps sound envelope information. We modeled amplitude changes occurring at typical speech envelope time-scales of four hierarchically-organized categories of natural (or synthetically derived) sounds. Using functional magnetic resonance, we assessed whether sound amplitude variations were represented in striate cortex and, as a control, in the temporal cortex. Sound amplitude mapping in V1 occurred regardless of the semantic content, was dissociated from the spectral properties of sounds and was not restricted to speech material. As in the temporal cortex, a spatially organized representation of amplitude modulation frequencies emerged in V1. Our results demonstrate that human striate cortex is a locus of representation of sound attributes. Copy rights belong to original authors. Visit the link for more info