Functional selectivity for social interaction perception in the human superior temporal sulcus during natural viewing

Area of Science:

• Neuroscience
• Social Cognitive Neuroscience
• Cognitive Psychology

Background:

• Recognizing social interactions is vital for humans.
• Previous research linked social interaction processing to the superior temporal sulcus (STS) using simple stimuli, and the medial prefrontal cortex (mPFC) using movies.
• The unique neural basis for social interaction perception in naturalistic stimuli, independent of other social cues, remains unclear.

Purpose of the Study:

• To investigate the unique brain mechanisms for perceiving naturalistic social interactions.
• To differentiate the neural processing of social interactions from other social and perceptual information in real-world stimuli.

Main Methods:

• Utilized functional magnetic resonance imaging (fMRI) with a movie-watching paradigm.
• Analyzed two independent fMRI datasets using advanced machine learning techniques, including voxel-wise encoding and variance partitioning.
• Controlled for covarying perceptual and social information like faces, voices, and theory of mind.

Main Results:

• Broad social-affective features predicted neural responses in social brain regions, including the STS and mPFC.
• The STS demonstrated robust and unique selectivity for social interactions, independent of other features.
• This STS selectivity for social interactions was consistent across two separate fMRI datasets.

Conclusions:

• Naturalistic social interaction perception recruits distinct neural circuitry within the STS.
• The STS plays a critical role in social understanding, separate from the theory of mind network (mPFC).
• Dedicated neural mechanisms in the STS support the perception of complex social dynamics in real-world scenarios.