Research Article

Study of EEG Inter-brain Synchrony during Nonverbal Facial Communication Games

Hao-Teng Hsu 1, Yuri Shelepin 2, Po-Lei Lee 1 *
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1 Department of Electrical Engineering, National Central University, Taoyuan City, 32001, Taiwan2 Laboratory of Physiology of Vision, Pavlov Institute of Physiology, Russian Academy of Sciences, St. Petersburg, 199034, Russia* Corresponding Author
International Journal of Clinical Medicine and Bioengineering, 6(3), September 2026, 1-15, https://doi.org/10.35745/ijcmb2026v06.03.0001
Submitted: 13 September 2024, Published: 30 September 2026
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ABSTRACT

Inter-brain synchrony can arise from task cooperation, neural mirroring, social interaction, or shared attention and perception. This study investigated brain synchrony between individuals with different linguistic backgrounds playing nonverbal facial communication games. Two eight-channel EEG systems were used to simultaneously measure participants located in different countries. Twelve participants in six groups were recruited to play an Easy and a Difficult nonverbal facial communication game, and their EEG signals were analyzed using two-layer empirical mode decomposition. Phase-locking values were obtained for frequency-modulated and amplitude-modulated intrinsic mode functions, and comparisons were made between the Easy and Difficult conditions. The results showed that as the number of execution times increased, the phase-locking values in the frontal cortex were significantly higher in both the alpha and beta bands under the Difficult condition.  This study demonstrated inter-brain synchrony in brain waves when two participants were engaged in a more challenging nonverbal cooperative game.
Keywords: Electroencephalography, Empirical mode decomposition, Hyperscan

CITATION (APA)

Hsu, H.-T., Shelepin, Y., & Lee, P.-L. (2026). Study of EEG Inter-brain Synchrony during Nonverbal Facial Communication Games. International Journal of Clinical Medicine and Bioengineering, 6(3), 1-15. https://doi.org/10.35745/ijcmb2026v06.03.0001

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