Interpersonal brain synchronization during face-to-face economic exchange between acquainted dyads

Area of Science:

• Neuroscience
• Social Neuroscience
• Cognitive Neuroscience

Background:

• Interpersonal brain synchronization (IBS) is observed during social interactions.
• Previous studies indicated face-to-face interactions with strangers increase IBS.
• The effect of IBS in acquainted pairs remains unclear.

Purpose of the Study:

• To investigate if face-to-face interactions increase IBS in acquainted pairs.
• To explore the influence of partner familiarity on neural synchronization.
• To examine brain activity during an economic game in different interaction settings.

Main Methods:

• Functional near-infrared spectroscopy (fNIRS) hyperscanning was used to record neural activity.
• Participants were acquainted pairs playing an ultimatum game.
• Two conditions were tested: face-to-face and face-blocked virtual economic exchange.

Main Results:

• No significant increase in cooperative behavior or task-induced IBS was observed in face-to-face interactions between acquainted pairs.
• Pair-specific IBS was significant in the task condition, not due to face-to-face interaction.
• Significant IBS was found in frontal and temporal brain regions.

Conclusions:

• Face-to-face interaction in acquainted pairs does not appear to increase interpersonal brain synchronization.
• IBS is influenced by the specific individuals interacting and the nature of the interaction.
• Findings highlight the context-dependent nature of neural synchronization in social settings.