Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Department of Neurological Surgery, University of California, San Francisco, 400 Parnassus Avenue, San Francisco, CA 94143, USA.
Curr Biol. 2021 Feb 8;31(3):601-612.e3. doi: 10.1016/j.cub.2020.11.035. Epub 2020 Nov 25.
Vision is the primary sense humans use to evaluate and respond to threats. Understanding the biological underpinnings of the human threat response has been hindered by lack of realistic in-lab threat paradigms. We established an immersive virtual reality (VR) platform to simultaneously measure behavior, physiological state, and neural activity from the human brain using chronically implanted electrodes. Subjects with high anxiety showed increased visual scanning in response to threats as compared to healthy controls. In both healthy and anxious subjects, the amount of scanning behavior correlated with the magnitude of physiological arousal, suggesting that visual scanning behavior is directly linked to internal state. Intracranial electroencephalography (iEEG) recordings from three subjects suggested that high-frequency gamma activity in the insula positively correlates with physiological arousal induced by visual threats and that low-frequency theta activity in the orbitofrontal cortex (OFC) negatively correlates with physiological arousal induced by visual threats. These findings reveal a key role of eye movements and suggest that distinct insula and OFC activation dynamics may be important for detecting and adjusting human stress in response to visually perceived threats.
视觉是人类用于评估和应对威胁的主要感觉。由于缺乏现实的实验室威胁范式，人类威胁反应的生物学基础一直难以理解。我们建立了一个沉浸式虚拟现实 (VR) 平台，使用慢性植入电极同时测量人类大脑的行为、生理状态和神经活动。与健康对照组相比，高焦虑组在面对威胁时表现出更多的视觉扫视。在健康和焦虑的受试者中，扫视行为的数量与生理唤醒的幅度相关，这表明视觉扫视行为与内部状态直接相关。三名受试者的颅内脑电图 (iEEG) 记录表明，岛叶的高频伽马活动与视觉威胁引起的生理唤醒呈正相关，而眶额皮质 (OFC) 的低频 theta 活动与视觉威胁引起的生理唤醒呈负相关。这些发现揭示了眼球运动的关键作用，并表明岛叶和 OFC 激活动态的不同可能对检测和调节人类对视觉感知威胁的应激反应很重要。
