Schedule of Events | Symposia

The Role of the Temporoparietal Junction in Theory of Mind: Evidence from Intracranial EEG

Poster Session A - Saturday, March 29, 2025, 3:00 – 5:00 pm EDT, Back Bay Ballroom/Republic Ballroom

Shweta Soni¹ (shwetanbrc@gmail.com), Julia WY Kam¹, Fady Girgis¹; ¹University of Calgary

Theory of Mind (ToM), a core mental process of human social cognition, is the ability to attribute thoughts, beliefs and intentions to oneself and others, and to understand that these mental states can differ from others. While neuroimaging techniques suggest the involvement of a variety of brain areas within the default mode network in ToM, comprehensive investigations of the neurophysiological basis of ToM remain limited. To address this, we examined intracranial EEG (iEEG) in 13 pharmacoresistant epileptic patients during a ToM task. We recorded brain responses from electrodes implanted over the temporoparietal junction (TPJ) and other areas while participants read ToM stories and responded via keyboard to associated ToM and control questions. Our results revealed significantly greater high-frequency broadband activity (70–170 Hz) in the TPJ in response to ToM questions compared to control questions. Moreover, TPJ electrodes showed significantly more power in higher frequencies during ToM than non-TPJ (i.e., insula as the control region) electrodes, suggesting a key role of the TPJ in supporting ToM processes. Leveraging the millimeter-scale spatial and millisecond-scale temporal resolution of iEEG, this study provides crucial insights into the spatiotemporal dynamics of ToM processes and holds significant implications for understanding psychiatric and neurological disorders like autism spectrum disorder, schizophrenia, and social anxiety disorder that are characterized by challenges in ToM processes. Keywords: Neuroimaging; Intracranial EEG; Theory of Mind; Social cognition; Neurophysiology

Topic Area: ATTENTION: Other