School of Psychological Sciences, University of Haifa, Haifa 3498838, Israel.
Division of Medical Psychology, Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn 53105, Germany.
Soc Cogn Affect Neurosci. 2022 Feb 3;17(1):142-150. doi: 10.1093/scan/nsab122.
Lonely people often crave connectedness. However, they may also experience their environment as threatening, entering a self-preserving state that perpetuates loneliness. Research shows conflicting evidence about their response to positive social cues, and little is known about their experience of observed human touch. The right inferior frontal gyrus (rIFG) is part of an observation-execution network implicated in observed touch perception. Correlative studies also point to rIFG's involvement in loneliness. We examined the causal effect of rIFG anodal transcranial direct current stimulation on high- and low-loneliness individuals observing human touch. In a cross-over design study, 40 participants watched pictures of humans or objects touching or not touching during anodal and sham stimulations. Participants indicated whether pictures contained humans or objects, and their reaction time was measured. Results show that the reaction time of low-loneliness individuals to observed human touch was significantly slower during anodal stimulation compared to high-loneliness individuals, possibly due to them being more emotionally distracted by it. Lonely individuals also reported less liking of touch. Our findings support the notion that lonely individuals are not drawn to positive social cues. This may help explain the perpetuation of loneliness, despite social opportunities that could be available to lonely people.
孤独的人常常渴望与他人建立联系。然而，他们也可能会感到周围的环境充满威胁，从而进入一种自我保护的状态，使孤独感持续存在。研究表明，他们对积极的社交线索的反应存在相互矛盾的证据，而对于他们对观察到的人类触摸的体验知之甚少。右侧额下回（rIFG）是参与观察到的触觉感知的观察-执行网络的一部分。相关研究也指出 rIFG 与孤独感有关。我们研究了 rIFG 阳极经颅直流电刺激对高孤独感和低孤独感个体观察人类触摸的因果效应。在一项交叉设计研究中，40 名参与者在阳极刺激和假刺激期间观看人类或物体接触或不接触的图片。参与者需要指出图片中是否包含人类或物体，并测量他们的反应时间。结果表明，与高孤独感个体相比，低孤独感个体在阳极刺激下对观察到的人类触摸的反应时间明显较慢，这可能是因为他们对其感到更加情绪化的分心。孤独的个体也报告对触摸的喜爱程度较低。我们的研究结果支持了这样一种观点，即孤独的个体不会被积极的社交线索所吸引。这可能有助于解释孤独感的持续存在，尽管孤独的人可能有社交机会。
