Hand gestures alert auditory cortices: Possible impacts of learning on foreign language processing

Abstract

When acquiring a foreign language, the first challenge is to break into the speech stream to identify basic linguistic units. The present study tested the hypothesis that hand gestures facilitate this process by alerting auditory cortices to attend to and identify meaningful phonemic information. During fMRI data acquisition, participants watched videos of an actor speaking in Russian under three conditions. Sentences were produced with just speech alone or were accompanied by two types of hand gestures: 1) metaphoric gesture and 2) free gesture. The main finding was that there was increased auditory cortex activation when both types of gestures accompanied speech compared to speech alone, but there were no differences between the two speech + gesture conditions (or gesture alone conditions). These results suggest that hand gestures may play a role in focusing attention to auditory processing to increase capacity when listening to novel speech in a foreign language.