 Hyperscanning is a brain imaging technique that measures brain synchrony caused by social interactions. Recent research on hyperscanning has revealed substantial interbrain synchrony, IBS, but little is known about the link between IBS and mental workload. To study this link, we conducted an experiment consisting of button pressing tasks of three different difficulty levels for the cooperation and competition modes with 56 participants aged 23.7 and hashtag X00B1, 3.8 years, mean and hashtag X00B1, standard deviation. We attempted to observe IBS using functional near-infrared spectroscopy, FNIRS, and galvanic skin response, GSR, to assess the activities of the human autonomic nervous system. We found that the IBS levels increased in a frequency band of 0.075 and hashtag X2013, 0.15 Hz, which was unrelated to the task repetition frequency in the cooperation mode according to the task difficulty level. Significant relative interbrain synchrony, ribs, increases were observed in 3 and 10 channels out of 15 for the hard tasks compared to. This article was authored by Jin Wu Park, Jae Young Shin, and Ji Chai Jung. We are article.tv, links in the description below.