The amygdala, social behavior, and danger detection
The amygdala, social behavior, and danger detection
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DOI：
10.1196/annals.1280.015
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发表时间：
2003-01-01
期刊：
影响因子：
--
通讯作者：
Amaral, DG
中科院分区：
文献类型：
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作者：
Amaral, DG
杏仁核是颞叶前部的一个独特部分，涉及多种功能，包括恐惧的表达、记忆的调节和社会沟通的调解。虽然对啮齿动物的研究通常涉及情感，但对非人类灵长类动物和人类的研究大多涉及杏仁核在感知社会信号（如面部表情）和维持社会地位（如灵长类动物的统治等级制度）方面的作用。我们已经建立了一个研究项目，其主要目标是定义构成物种典型社会交流基础的神经系统。该计划的第一阶段是在杏仁核对物种典型的社会行为至关重要的前提下启动的。我们试图更详细地研究在杏仁核的离散、双侧损伤之后社会行为的损害。然而，我们发现，双侧杏仁核受损的成熟恒河猴不仅能够进行物种典型的社会行为，而且实际上参与了更多的亲缘性社会互动。受伤的动物也表现出对通常会引起恐惧的刺激（如蛇的复制品）缺乏恐惧。在第二项正在进行的恒河猴婴儿系列研究中，我们正在研究杏仁核在发育过程中是否对获得社会知识至关重要。在两周大时接受双侧杏仁核损伤并由其生母抚养的幼仔动物表现出同龄所有预期的社会行为。这些动物和成年动物一样，表现出对蛇等物体的恐惧。然而，与成年人不同的是，当他们被置于新的社会环境中时，他们会表现出更多的恐惧。这些研究的结果与杏仁核对物种典型的社会行为或在发育过程中获得社会知识不是必需的结论是最一致的。我们假设杏仁核是评估环境潜在危险系统的关键组成部分。因此，它对社会行为具有调节作用——也就是说，当新同类被评估为潜在对手时，它通常会抑制与它们的社会互动。这一观点预测，杏仁核的过度活跃与恐惧或焦虑的增加有关，并可能导致社交恐惧症等疾病。
The amygdala is a distinctive portion of the anterior temporal lobe that has been implicated in a variety of functions including expression of fear, modulation of memory, and mediation of social communication. While work on the rodent amygdala often deals with emotion, much of the research in nonhuman primates and in man deals with its role in the perception of social signals, such as facial expressions, and the maintenance of social position, such as in primate dominance hierarchies. We have established a program of research that has as its major goal the definition of neural systems that underlie species-typical social communication. A first phase of the program was launched on the premise that the amygdala is essential for species-typical social behavior. We sought to examine in more detail the impairments of social behavior that followed discrete, bilateral lesions of the amygdala. We found, however, that mature rhesus monkeys with bilateral lesions of the amygdala not only were capable of species-typical social behavior, but actually engaged in more affiliative social interactions. The lesioned animals also demonstrated a striking lack of fear of normally fear-inducing stimuli such as replicas of snakes. In a second, ongoing series of studies in the infant rhesus monkey, we are examining whether the amygdala is essential for gaining social knowledge during development. Infant animals that receive bilateral lesions of the amygdala at two weeks of age and are raised by their biological mothers demonstrate all expected social behaviors for their ages. These animals, like the adults, demonstrate a lack of fear of objects such as snakes. However, unlike the adults, they demonstrate more fear when placed into novel social situations. The results from these studies are most consistent with the conclusion that the amygdala is not necessary for species-typical social behavior or for gaining social knowledge during development. We hypothesize that the amygdala is a critical component of a system that evaluates the environment for potential dangers. As such, it has a modulatory role on social behavior-that is, it typically inhibits social interaction with novel conspecifics while they are evaluated as potential adversaries. This perspective predicts that hyperactivity of the amygdala would be associated with increased fear or anxiety and may contribute to disorders such as social phobia.