Neural representation of nouns and verbs in congenitally blind and sighted individuals

In blind individuals, language processing activates not only classic language networks, but also the "visual" cortex. What is represented in visual areas when blind individuals process language? Here, we show that area V5/MT in blind individuals, but not other visual areas, responds differently to spoken nouns and verbs. We further show that this effect is present for concrete nouns and verbs, but not abstract or pseudo nouns and verbs. This suggests that area V5/MT in blind individuals represents physical properties of noun and verb referents, salient in the concrete word category, but not conceptual or grammatical distinctions, present across categories. We propose that this motion-sensitive area captures systematically different motion connotations of objects (nouns) and actions (verbs). Overall, our findings suggest that responses to language in the blind visual cortex can be deconstructed to representing physical properties of words' referents, which are projected onto typical functional organization of this region.