Dyad averaged BMI-dependent interbrain synchrony during continuous mutual prediction in social coordination

Area of Science:

• Psychology
• Neuroscience
• Social Interaction Research

Background:

• Obesity is associated with psychological challenges, including social stigmatization and difficulties in social connections.
• Limited research exists on real-time social dynamics within dyads exhibiting diverse body mass index (BMI) levels.

Purpose of the Study:

• To investigate the impact of dyadic body mass index (BMI) on real-time social coordination during a joint finger-tapping task.
• To examine interbrain synchrony and behavioral coordination in relation to BMI during different interaction conditions.

Main Methods:

• Utilized a joint finger-tapping task involving participant dyads.
• Monitored brain activity using functional near-infrared spectroscopy (fNIRS).
• Compared behavioral and interbrain synchrony across Bidirectional Interaction, Unidirectional Interaction, and No Interaction conditions.

Main Results:

• Both Bidirectional and Unidirectional Interaction conditions showed greater behavioral and interbrain synchrony than the No Interaction condition.
• In the Bidirectional Interaction condition, higher dyadic BMI was linked to poorer behavioral coordination.
• Higher dyadic BMI also correlated with reduced interbrain synchrony specifically in the Bidirectional Interaction condition.

Conclusions:

• Social coordination, especially in tasks requiring continuous mutual prediction and adjustment, is influenced by the body mass index (BMI) of interacting individuals.
• Dyadic BMI may play a significant role in modulating the neural mechanisms underlying social synchrony and coordination.