Neural basis for sentence comprehension: Grammatical and short‐term memory components

We monitored regional cerebral activity with BOLD fMRI while subjects were presented written sentences differing in their grammatical structure (subject‐relative or object‐relative center‐embedded clauses) and their short‐term memory demands (short or long antecedent‐gap linkages). A core region of left posterior superior temporal cortex was recruited during all sentence conditions in comparison to a pseudofont baseline, suggesting that this area plays a central role in sustaining comprehension that is common to all sentences. Right posterior superior temporal cortex was recruited during sentences with long compared to short antecedent‐gap linkages regardless of grammatical structure, suggesting that this brain region supports passive short‐term memory during sentence comprehension. Recruitment of left inferior frontal cortex was most clearly associated with sentences that featured both an object‐relative clause and a long antecedent‐gap linkage, suggesting that this region supports the cognitive resources required to maintain long‐distance syntactic dependencies during the comprehension of grammatically complex sentences. Hum. Brain Mapping 15:80–94, 2001. © 2001 Wiley‐Liss, Inc.