Brain and Mind Institute, The University of Western Ontario, London, ON, Canada.
Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, The University of Western Ontario, London, ON, Canada.
Soc Neurosci. 2020 Feb;15(1):36-51. doi: 10.1080/17470919.2019.1626763. Epub 2019 Jun 10.
Personal space regulation ensures the maintenance of a margin of safety between the individual and the surrounding world. However, little is known about the specific neural mechanisms implicated in regulating the distance from conspecifics versus non-social stimuli. Here, we investigated the neural correlates of personal space intrusions by social versus non-social stimuli. Thirty volunteers underwent fMRI scanning while viewing approaching or withdrawing faces (Social) and insects/arachnids (Non-social). Preferred distance to the stimuli was assessed behaviourally in a computerized task, and in real life. Results showed that approaching social and non-social stimuli of varying threat levels elicited activation of frontoparietal regions previously linked to peripersonal space, as well as of the midbrain periaqueductal gray, suggesting the engagement of defensive mechanisms by personal space intrusions. However, functional connectivity patterns of the midbrain differed for social and non-social stimuli, with enhanced coupling with the premotor cortex to approaching social stimuli. Additionally, connectivity strength between the midbrain and the premotor cortex was associated with preferred interpersonal distance. These findings highlight a common defensive architecture implicated in personal space regulation to social and non-social stimuli, and the specific neural mechanisms involved in regulating the distance from conspecifics.
个人空间调节确保了个体与周围世界之间安全距离的维持。然而，对于调节与同类相比与非社交刺激的距离所涉及的特定神经机制知之甚少。在这里，我们研究了社交与非社交刺激引起的个人空间侵犯的神经相关性。三十名志愿者在观看接近或远离面部（社交）和昆虫/蛛形纲动物（非社交）的 fMRI 扫描时进行了扫描。在计算机化任务和现实生活中，通过行为评估了对刺激的偏好距离。结果表明，接近不同威胁水平的社交和非社交刺激会引发与peripersonal 空间相关的额顶叶区域以及中脑导水管周围灰质的激活，表明个人空间侵犯会引发防御机制。然而，社交和非社交刺激的中脑功能连接模式不同，与接近社交刺激时的运动前皮层的耦合增强。此外，中脑与运动前皮层之间的连接强度与人际距离偏好相关。这些发现强调了一种共同的防御结构，涉及社交和非社交刺激的个人空间调节，以及涉及调节与同类相比的距离的特定神经机制。
