Interpersonal synchrony enhanced through 20 Hz phase-coupled dual brain stimulation

Area of Science:

• Neuroscience
• Social Cognition
• Motor Control

Background:

• Interpersonal synchrony in movement is crucial for social behavior.
• Theories propose a link between synchronized brain oscillations and synchronized movements.

Purpose of the Study:

• To investigate the causal relationship between interpersonal brain oscillations and movement synchrony.
• To determine if inducing beta band oscillations enhances interpersonal movement synchrony.

Main Methods:

• Used transcranial alternating current stimulation (tACS) to induce beta band (20 Hz) oscillations in the motor cortex of paired individuals.
• Participants performed a rhythmic finger-tapping task.
• Compared in-phase, anti-phase, and sham tACS stimulation during movement preparation and execution.

Main Results:

• In-phase 20 Hz beta band stimulation significantly enhanced interpersonal movement synchrony compared to anti-phase or sham conditions.
• The enhancement was most prominent for initial taps after the preparatory period.
• No synchrony enhancement was observed with 2 Hz or 10 Hz stimulation.

Conclusions:

• Phase-coupling of beta band neural oscillations in motor cortices facilitates interpersonal alignment of sensorimotor processes.
• This alignment supports rhythmic action initiation and improves synchronous movement.
• Phase-locked dual brain stimulation is a valuable tool for studying the causal impact of interpersonal brain synchrony.