Poster B71, Sunday, March 26, 8:00 – 10:00 am, Pacific Concourse
Motor cortex in figurative language comprehension: a TMS study
Yury Shtyrov1,2, Elena Kulkova2, Matteo Feurra2, Andriy Myachykov2,3; 1Aarhus University, Denmark, 2NRU Higher School of Economics, Moscow, 3Northumbria University, Newcastle upon Tyne
The embodied cognition view postulates that comprehension of concrete action-related language involves the brain’s motor systems. It remains unclear, however, whether they similarly contribute to the processing of figurative and abstract language. Here, we used TMS of primary motor cortex (M1) to investigate its involvement in concrete and figurative language processing. Participants read literal (‘she took the bag’), idiomatic (‘she took the chance’) and metaphoric (‘she took the proposal’) sentences incorporating action-related words as well as action-unrelated and abstract sentences. Single-pulse TMS was delivered to left M1, right M1 or control site (vertex). Sentence comprehension was assessed using a semantic judgement task (SJT). While SJT reaction times were generally affected by TMS, this effect diverged between sentence types and hemispheres depending on the action reference. In the left hemisphere, comprehension of metaphoric and abstract sentences was inhibited by TMS regardless of the action verb inclusion. Literal and idiomatic sentences showed a similar pattern for action-unrelated stimuli while faster RTs were observed for literal and idiomatic expressions incorporating action words, suggesting a facilitatory effect of M1 TMS on their comprehension. Right-hemispheric TMS significantly facilitated processing of literal action-related sentences relative to action-unrelated ones, while RTs for other sentence types did not depend on action reference. Our data suggest that motor-related semantics engages motor cortex in the processing of both literal and idiomatic semantics, this effect being underpinned by differentially lateralised cortical networks. Metaphors, however, do not show similar reliance on action semantics, likely due to referential connections outside the motor cortex.
Topic Area: LANGUAGE: Semantic