The dorsolateral prefrontal cortex in idiom interpretation: An rTMS study

Neuropsychological studies have suggested that a prefrontal lesion can impair idiom comprehension. We tested the role of the dorsolateral prefrontal cortex (DLPFC) in idiom processing by using repetitive transcranial magnetic stimulation (rTMS) in normal participants. Each subject was presented with a written (idiomatic or literal) sentence followed by four pictures. rTMS was applied over left or right DLPFC or in a sham condition after picture presentation. Reaction times (RTs) decreased for the two types of sentence during rTMS, but accuracy was affected only in the case of idioms. The results show that both left and right DLPFC are involved in monitoring the idiomatic response, thus complementing neuropsychological studies.