The primate amygdala and the control of visual search of emotional stimuli

描述(申请人提供)：人类和猴子使用眼球运动来探索他们的世界，并在他们的视觉环境中识别情感和社会上重要的元素。通过面部表情、手势和姿势进行非语言社交交流的成功与否，关键取决于对他人发出的信号的快速而正确的评估。猴子和人类的眼睛在面部表情的视觉探索(扫描路径)过程中执行的扫视和注视序列受到两个过程的影响：自下而上的视觉过程将视觉注意力分配到图像的显著元素(例如眼睛)，以及自上而下的过程反映目标、专业知识和瞬时情绪状态。大多数精神障碍都伴随着异常的扫描路径，然而缺陷的来源却鲜为人知。观察到杏仁核受损的患者无法探索眼睛，并显示出与自闭症、精神分裂症、社交恐惧症和情感障碍患者类似的扫视路径异常，这表明杏仁核参与了面部探索过程中视觉注意力的引导。杏仁核在这一过程中的确切作用尚不清楚。杏仁核是两个具有分离功能的主要核群的复合体，我们认为不同的核群参与了扫描路径精化的自下而上和自上而下的组成部分。这项应用提供的资源将用于选择性地灭活猴子杏仁核的中央内侧和基底外侧核群，并确定每个核群对自下而上和自上而下的面孔探索过程的贡献。这一结果有望阐明杏仁核对获取社会和情感相关信息的贡献--这是设计更有效的干预社会情绪障碍的关键先决条件。 公共卫生相关性：这项应用的目标是确定灵长类杏仁核在将视觉注意力分配给具有增强的情感和社会意义的视觉目标方面的作用。该提议的核心假设是，在对面孔的视觉探索过程中，眼球运动的模式取决于自上而下和自下而上的过程，并且这些过程可以定位于不同的杏仁核群。核团的中央内侧群相互连接到脑干的反射和自主神经中心，被认为是为了形成一个有助于自下而上控制眼球运动的回路。相比之下，基底外侧核复合体在功能上与高级皮质视觉区域相连，预计将提供自上而下的眼球运动控制。为了验证这些假设，我们将使用可逆失活来分别操作杏仁复合体的两个组成部分，并测量视觉引导的眼跳和探索面部表情图像的变化。这个项目反映了一种新的综合方法，使用可逆失活和电生理控制下的电生理学相结合，提供神经活动和行为之间的因果推断，以及扫描路径监测，揭示未经训练的行为对自然刺激的反应。结果将分离两个杏仁核成分在引导眼球运动的回路中的作用，澄清杏仁核的两个潜在的临床相关功能。

DESCRIPTION (provided by applicant): Humans and monkeys use eye movements to explore their world and identify, in their visual environment, the emotionally and socially important elements. The success of non-verbal social communication with facial expressions, gestures, and postures depends critically on the fast and correct evaluation of the signals displayed by others. The sequence of saccades and fixations executed by the eyes of monkeys and humans during the visual exploration of facial expressions (scanpaths) are influenced by two processes: bottom-up visual processes which allocate visual attention to salient elements of the image (e.g., the eyes), and top-down processes that reflect goals, expertise, and momentary emotional states. The majority of psychiatric disorders are accompanied by aberrant scanpaths, yet the source of the deficit is poorly understood. The observation that patients with amygdala damage fail to explore the eyes and show scanpath abnormalities similar to patients with autism, schizophrenia, social phobia, and affective disorders, suggests that the amygdala is involved in guiding visual attention during face exploration. The precise contribution of the amygdala to this process is unknown. The amygdala is a complex of two main nuclear groups with dissociable functions and we propose that different nuclear groups are involved in the bottom-up and top-down components of scanpath elaboration. The resources afforded by this application will be used to selectively inactivate the centromedial and basolateral nuclear groups of the monkey amygdala and determine the contribution of the each nuclear group to bottom-up and top-down processes of face exploration. The results are expected to clarify the contribution of the amygdala to the acquisition of socially and emotionally relevant information-a critical prerequisite in designing a more effective intervention in socio-emotional disorders. PUBLIC HEALTH RELEVANCE: The goal of this application is to determine the role of the primate amygdala in allocating visual attention to visual targets of enhanced emotional and social significance. The proposal is centered on the hypothesis that the pattern of eye movements during the visual exploration of faces depends on both top-down and bottom-up processes and that these processes can be localized to different groups of amygdaloid nuclei. The centromedial group of nuclei, reciprocally connected to reflexive and autonomic centers in the brain-stem, are hypothesized for form a circuit that contributes to bottom-up control of eye movements. In contrast, the basolateral nuclear complex, functionally connected to high-level cortical visual areas, is expected to provide top-down control of eye movements. To test these hypotheses, we will use reversible inactivation to separately manipulate the two components of the amygdalar complex, and measure the alterations in visually-guided saccades and in the exploration of images of facial expressions. This project reflects a novel integrative approach using a combination of reversible inactivation with electrophysiology under electrophysiological control, which affords causal inference between neural activity and behavior, and scanpath monitoring, which reveals untrained behavioral responses to naturalistic stimuli. The outcome will dissociate the role of two amygdaloid components within the circuit that guides eye movements, clarifying two potentially clinically relevant functions of the amygdala.