Neural basis of social-categorization function of language

Languages provide social-category markers that tag people as one or another social group. We investigate how the brain sorts words into one or another language category as a neural basis of this social-categorization function of language. We show that a neural network, including the anterior temporal, insular, orbital frontal, and ventral occipito-temporal cortices in both hemispheres, computes correlation distances between two words to represent intra-language similarity and inter-language difference during categorization of visual words of alphabetic and non-alphabetic languages. These processes occur as early as 150 ms post-stimulus, recruit within-hemisphere functional connections, operate independently of words’ semantic meanings and pronunciations, and exhibit consistently across individuals with diverse language backgrounds. These findings advance our understanding of the neural mechanisms of the social-categorization function of language.