Grammatical classes in the brain: MVPA reveals the cortical signature of verbs, adjectives and nouns

This study identified selective functional brain correlates of the distinct grammatical categories of verb, adjective and noun within a left lateralized language network. These results provide a robust indication of the neural underpinning of nouns and the first evidence on the representation of adjectives as grammatical category, thus making specific contributions also to the study of conceptual combination processes involving noun+adjective combinations, associated with the left anterolateral temporal lobe. Moreover, these data confirm the most consistent neuroanatomical findings from previous studies on verb-selectivity and provide new evidence on how grammatical category-specific information is represented in the brain when stimuli are controlled for crucial semantic features of verbs, as opposed to other word classes, and the effect of familiarity, imageability and concreteness is ruled out. In summary, this study specifically expands the current knowledge on how grammatical categories are captured in the brain, by assessing the role of language-sensitive regions in representing word classes and by identifying the kind of distinctions that drives neural selectivity.