Transcranial magnetic stimulation over left inferior frontal and posterior temporal cortex disrupts gesture-speech integration

Zhao, Wanying; Riggs, Kevin; Schindler, Igor; Holle, Henning

Abstract

Language and action naturally occur together in the form of co-speech gestures and there is now convincing evidence that listeners display a strong tendency to integrate semantic information from both domains during comprehension. A contentious question, however, has been which brain areas are causally involved in this integration process. In previous neuroimaging studies, left inferior frontal gyrus (IFG) and posterior middle temporal gyrus (pMTG) have emerged as candidate areas, however, it is currently not clear whether these areas are causally or merely epiphenomenally involved in gesture-speech integration. In the present series of experiments, we directly tested for a potential critical role of IFG and pMTG by observing the effect of disrupting activity in these areas using transcranial magnetic stimulation (TMS) in a mixed gender sample of healthy human volunteers. The outcome measure was performance on a Stroop-like gesture task (Kelly et al., 2010a), which provides a behavioural index of gesture-speech integration. Our results provide clear evidence that disrupting activity in IFG and pMTG selectively impairs gesture-speech integration, suggesting that both areas are causally involved in the process. These findings are consistent with the idea that these areas play a joint role in gesture-speech integration, with IFG regulating strategic semantic access via top-down signals acting upon temporal storage areas.

• Journal Article Type: Article
• Publication Date: Feb 21, 2018
• Print ISSN: 0270-6474
• Electronic ISSN: 1529-2401
• Publisher: Society for Neuroscience
• Peer Reviewed: Peer Reviewed
• Volume: 38
• Issue: 8
• Article Number: 1748-17
• Pages: 1891-1900
• APA6 Citation: Zhao, W., Riggs, K., Schindler, I., & Holle, H. (2018). Transcranial magnetic stimulation over left inferior frontal and posterior temporal cortex disrupts gesture-speech integration. Journal of Neuroscience, 38(8), 1891-1900. https://doi.org/10.1523/JNEUROSCI.1748-17.2017
• DOI: https://doi.org/10.1523/JNEUROSCI.1748-17.2017
• Keywords: General Neuroscience
• Copyright Statement: ©2018 the Authors