Cerebellar involvement in verb generation: an fMRI study.

A possible role of the human cerebellum in the generation of verbs corresponding to presented nouns has been suggested. Previous functional brain imaging studies have compared generation of verbs with the reading of nouns as a measure of verb generation. In the present fMRI study involving healthy human subjects, the effects of speech articulation and motor imagery associated with verb production were investigated in greater detail. Generation of verbs to visually presented nouns was compared to a condition in which subjects read those same verbs that had been individually generated by each subject. Activation in lobule HVI/Crus I of the right cerebellar hemisphere was found as a measure of verb generation. In contrast, reading of verbs as a measure of speech articulation evoked cerebellar activations in both left and right paravermal lobule VI. These results suggest an involvement of the right lateral cerebellar hemisphere in linguistic functions during verb generation. Alternatively, effects of inner speech could also possibly explain the results.