Categorical representation from sound and sight in the ventral occipito-temporal cortex of sighted and blind

Abstract

and Olivier Collignon (olivier.collignon@uclouvain.be). AbstractThe Ventral Occipito-Temporal Cortex (VOTC) shows reliable category selective response to visual information. Do the development, topography and information content of this categorical organization depend on visual input or even visual experience? To further address this question, we used fMRI to characterize the brain responses to eight categories (4 living, 4 non-living) presented acoustically in sighted and early blind individuals, and visually in a separate sighted group. Using a combination of decoding and representational similarity analyses, we observed that VOTC reliably encodes sounds categories in the sighted and blind groups, using a representational structure strikingly similar to the one found in vision. Moreover, we found that the representational connectivity between VOTC and large-scale brain networks was substantially similar across modalities and groups. Blind people however showed higher decoding accuracies and higher inter-subject consistency for the representation of sounds in VOTC, and the correlation between the representational structure of visual and auditory categories was almost double in the blind when compared to the sighted group. Crucially, we also demonstrate that VOTC represents the categorical membership of sounds rather that their acoustic features in both groups. Our results suggest that early visual deprivation triggers an extension of the intrinsic categorical organization of VOTC that is at least partially independent from vision.

The contribution of object size, manipulability, and stability on neural responses to inanimate objects

“…By positing a key role for domain-related processing, this view provides an account of data from congenitally blind individuals, who show response preferences in similarly located regions of occipitotemporal cortex when hearing the names of animate versus inanimate objects or big versus small artifacts (e.g., Mahon et al, 2009; Wolbers et al, 2011; He et al, 2013; Peelen et al, 2013; Bi et al, 2015; Mattioni et al, 2020). Since ontogenetic visual experience could not have contributed to the similar patterns of object-preferring effects in high-level visual areas in congenitally blind and sighted individuals, it invites the conclusion that the observed specialization predates such experience.…”

Visual object categorization in infancy

“…The organization of the human visual cortex by object categories appears to be a hallmark in the evolution of the primate brain: it is replicated in the visual cortex of monkeys 7,19 , and is resistant to variations of individual visual experience [20][21][22][23] . A similar organization across species and conspecifics with different environment and life-long visual experience, suggests a neural code optimized by evolution.…”

Brain Regions Involved in Conceptual Retrieval in Sighted and Blind People

“…Moreover, previous tasks mostly involved the discrimination of concepts belonging to distinct superordinate categories rather than the analysis of concepts as individual entities (Handjaras et al, 2017) based on their idiosyncratic perceptual features. Therefore, it may not surprising that associative regions (e.g., pMTG) or even regions of the anterior part of the ventral occipital-temporal cortex ( VOTC) that are not strictly visual but receive multiple inputs from different sensory and nonsensory systems (such as the emotional, language, or navigation network) might show preferential responses to some specific superordinate categories independently of sensory inputs or even sensory (visual) experience (Mattioni et al, 2019;Handjaras et al, 2017;Peelen & Downing, 2017;van den Hurk, Van Baelen, & Op de Beeck, 2017).…”