The neurobiology of communication in natural settings
Abstracts
Communication in natural settings is accompanied by an abundance of contextual information, including both sensory information external to the listener and knowledge or expectations internal to the listener. Most language research discards context in favor of studying isolated speech sounds or words. Rather than take this approach, much of my research investigates how the brain makes use of contextual information contained in more ecologically relevant and context-rich stimuli. I will present experiments that provide evidence that the cortical networks supporting speech perception and language comprehension are not functionally fixed but, rather, re-organize themselves depending on the type of context available to listeners. The patterns of activity in these different networks support a active model in which the motor system’s ability to predict the forthcoming sensory consequences of executing a motor plan associated with observed movements or discourse content play a central role in communication. Results suggest that prediction constrains the identification of speech sounds in the case of speech-associated mouth movements and the semantic interpretation of the intended message in the case of co-speech gestures and discourse context. Thus, the neurobiology of natural communication is supported by a dynamic and active mechanism that makes use of context. This contrasts with most contemporary views of the neurobiology of speech perception and language comprehension as context insensitive and comprising a relatively static and circumscribed set of cortical areas.