Cortical representation of verb processing in sentence comprehension: Number of complements, subcategorization, and thematic frames

The processing of various attributes of verbs is crucial for sentence comprehension. Verb attributes include the number of complements the verb selects, the number of different syntactic phrase types (subcategorization options), and the number of different thematic roles (thematic options). Two functional magnetic resonance imaging experiments investigated the cerebral location and pattern of activation of these attributes. Experiment 1 tested the effect of number of complements. Experiment 2 tested the number of options of subcategorization and of thematic frames. A group of mismatch verbs with different number of options for subcategorization and thematic frames was included to distinguish between the effects of these attributes. Fourteen Hebrew speakers performed a semantic decision task on auditorily presented sentences. Parametric analysis revealed graded activations in the left superior temporal gyrus and the left inferior frontal gyrus in correlation with the number of options. By contrast, the areas that correlated with the number of complements, the right precuneus and the right cingulate, were not conventionally linguistic. This suggests that processing the number of options is more specifically linguistic than processing the number of complements. The mismatch verbs showed a pattern of activation similar to that of the subcategorization group but unlike that of the thematic frames group. By implication, and contrary to claims by some linguists, subcategorization seems indispensable in verb processing.