Different neural networks for conceptual retrieval in sighted and blind

Abstract

We investigated the experiential bases of knowledge by asking whether people that perceive the world in a different way also show a different neurobiology of concepts. We characterized the brain activity of early-blind and sighted individuals during a conceptual retrieval task in which participants rated the similarity between color and action concepts. Between-categories analysis showed that, whereas multimodal concepts (action) activated a similar fronto-temporal network in the sighted and blind, color knowledge activated partially different brain regions in the two groups, with the posterior portion of the right IPS being significantly more active in the sighted compared to the blind. Interestingly, regions that were similarly activated in sighted and blind during conceptual processing (lpMTG for action, and precuneus for color), showed, however, an increased task-dependent connectivity with occipital regions in the blind. Finally, within-category adaptation analysis showed that word-pairs referring to perceptually similar color or actions led to repetitionsuppression in occipital visual areas in the sighted only, whereas adaptation was observed in language-related temporal regions in the blind. Our results show that visual deprivation changes the neural bases of conceptual retrieval, which is partially grounded in sensorimotor experience.Keywords: Concepts; Color; Action; Blindness; Neuroplasticity; fMRI; Adaptation . CC-BY-NC-ND 4.0 International license It is made available under a (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint . http://dx.doi.org/10.1101/384552 doi: bioRxiv preprint first posted online Aug. 23, 2018; CONCEPTUAL KNOWLEDGE IN BLIND 3Significance statement: (max 120 words) Do people with different sensory experience conceive the world differently? We tested whether conceptual knowledge builds on sensory experience by looking at the neurobiology of concepts in early blind individuals. We show that cortical regions involved in the processing of multimodal concepts (actions) are mostly similar in blind and sighted, whereas strictly visual concepts (colors) activated partially different brain topographies. Moreover, brain regions classically involved in conceptual retrieval showed different connectivity profiles in the blind, working in concert with reorganized "visual" areas. Finally, we further demonstrate that perceptual distance between concepts is represented in the visual cortex of the sighted, but not the blind.Blindness changes how the brain implements conceptual knowledge, which is partially grounded in sensorimotor experience.

Ecological meanings: A consensus paper on individual differences and contextual influences in embodied language

“…To conclude, unique sensorimotor experiences, either congenital or acquired, or the result of specific training, such as sports, sometimes lead to differences in conceptual representations and language processing. However, these differences may be difficult to detect: the flexibility of the conceptual system makes use of compensation strategies, as missing semantic information could be extracted from other sources, such as word cooccurrences (Bottini et al, 2020), intact perceptual channels (Cattaneo et al, 2008), or emotion . Notably, while differences in experiences are relatively easy to identify or manipulate, variability in cognitive processing of those experiences (such as mental simulation or imagery strategies) is more subtle and might be considered a mediator between past sensorimotor inputs and linguistic tasks at hand.…”

Shared understanding of color among congenitally blind and sighted adults

“…Finally, the present results are not inconsistent with the possibility of other color knowledge, not studied here, that differs among sighted and blind people. Indeed, recent evidence suggests both neural similarities and differences between blind and sighted people's representations of color: while objects with similar colors show similar patterns of activity in the anterior temporal lobe of both blind and sighted individuals, color perception regions in visual cortex additionally encode color similarity in sighted individuals (70, see also [71][72]. The full typology of color knowledge in sighted and blind people remains to be fully described.…”