Faculty of Psychology, Southwest University, Chongqing, 400715, China.
Information Systems and Decision Sciences, California State University, Fullerton, CA, USA.
Brain Imaging Behav. 2021 Jun;15(3):1667-1675. doi: 10.1007/s11682-020-00361-z.
Human cooperation behavior based on reciprocal altruism has been a hallmark of ancient and modern societies. Prior studies have indicated that inter-brain synchronization (IBS) between partners could exist during cooperation. However, how the sex composition of dyads influences the neural synchronization is still poorly understood. Here, we adopted functional near-infrared spectroscopy (fNIRS) based hyperscanning and a task of building blocks to investigate the sex composition effect on IBS in face-to-face cooperation in a natural situation, by evaluating brain-to-brain interactions of forty-five same-sex and mixed-sex dyads. Results showed significantly stronger inter-brain synchronization in Brodmann area 10 (BA10) in cooperation. In addition, variance analysis indicated that only male-male dyads showed increased inter-brain synchronization in left inferior frontal region (i.e., BA10) specific to cooperation. More importantly, the inter-brain synchronization in male-male dyads was significantly greater than that in male-female and female-female dyads. These findings provide support for the impact of sex composition on social cooperation in a naturalistic interactive setting and extend our knowledge on the neural basis of face-to-face cooperation.
基于互惠利他主义的人类合作行为一直是古今社会的一个显著特征。先前的研究表明，在合作过程中，伙伴之间可能存在脑间同步（IBS）。然而，双元的性别构成如何影响神经同步还知之甚少。在这里，我们采用基于功能近红外光谱（fNIRS）的超扫描和积木任务，通过评估四十五个同性别和混合性别二元组的脑间相互作用，在自然情境下面对面合作中研究性别构成对 IBS 的影响。结果表明，合作中大脑区域 10（BA10）的脑间同步性明显增强。此外，方差分析表明，只有男性-男性二元组在合作时左额下回（即 BA10）的脑间同步性增加。更重要的是，男性-男性二元组的脑间同步性明显大于男性-女性和女性-女性二元组。这些发现为自然互动环境中性别构成对社会合作的影响提供了支持，并扩展了我们对面对面合作神经基础的认识。
