Neuronal interactions between mentalising and action systems during indirect request processing

Soc Cogn Affect Neurosci. 2016 Sep;11(9):1402-10. doi: 10.1093/scan/nsw062. Epub 2016 Apr 29.

Abstract

Human communication relies on the ability to process linguistic structure and to map words and utterances onto our environment. Furthermore, as what we communicate is often not directly encoded in our language (e.g. in the case of irony, jokes or indirect requests), we need to extract additional cues to infer the beliefs and desires of our conversational partners. Although the functional interplay between language and the ability to mentalise has been discussed in theoretical accounts in the past, the neurobiological underpinnings of these dynamics are currently not well understood. Here, we address this issue using functional imaging (fMRI). Participants listened to question-reply dialogues. In these dialogues, a reply is interpreted as a direct reply, an indirect reply or a request for action, depending on the question. We show that inferring meaning from indirect replies engages parts of the mentalising network (mPFC) while requests for action also activate the cortical motor system (IPL). Subsequent connectivity analysis using Dynamic Causal Modelling (DCM) revealed that this pattern of activation is best explained by an increase in effective connectivity from the mentalising network (mPFC) to the action system (IPL). These results are an important step towards a more integrative understanding of the neurobiological basis of indirect speech processing.

Keywords: dynamic causal modelling; embodied cognition; language comprehension; mentalising; neuropragmatics; semantics; theory of mind.

MeSH terms

  • Adolescent
  • Adult
  • Brain Mapping
  • Comprehension
  • Female
  • Humans
  • Interpersonal Relations
  • Magnetic Resonance Imaging
  • Motor Cortex / physiology
  • Neural Pathways / physiology
  • Neurons / physiology*
  • Prefrontal Cortex / physiology
  • Semantics
  • Speech Perception / physiology
  • Theory of Mind / physiology*
  • Young Adult