Primate Research Institute, Kyoto University, Inuyama, Japan.
Eur J Neurosci. 2012 May;35(9):1504-12. doi: 10.1111/j.1460-9568.2012.08061.x. Epub 2012 Apr 16.
The primate amygdala consists of several subnuclei. Neurons in this brain area have been known to respond to stimuli belonging to specific categories of objects, such as faces, animals, and artifacts. However, little is known about the functional differences among the nuclei of the primate amygdala. To clarify functional differences among these subnuclei in object categorization, we compared the responsiveness of neuronal populations among the lateral, basal and central nuclei of the monkey amygdala. The activity of 203 neurons was recorded while video clips of 13 stimuli belonging to three categories (monkey, human, and artifact) were presented. Of these neurons, 37, 39 and 37 neurons in the lateral, basal and central nuclei, respectively, responded to at least one of the stimuli. We applied a cluster analysis to the neuronal population responses from these nuclei, and also calculated information about the three categories and monkey identity from each neuronal population. We found that the three categories and monkey identity could be more properly classified by neuronal responsiveness in the central nucleus, which is an output gate of the amygdala, than by that in the lateral and basal nuclei. These results suggest that the information about objects suitable for the generation of appropriate emotional response is built up within the primate amygdala via an intra-amygdala network from the lateral nucleus to the central nucleus.
灵长类动物的杏仁核由几个亚核组成。人们已经知道，这个大脑区域的神经元会对属于特定物体类别（如人脸、动物和人工制品）的刺激做出反应。然而，对于灵长类动物杏仁核核团之间的功能差异知之甚少。为了阐明这些亚核在物体分类中的功能差异，我们比较了猴子杏仁核的外侧核、基底核和中央核中神经元群体的反应。当呈现属于三个类别（猴子、人类和人工制品）的 13 个刺激的视频剪辑时，记录了 203 个神经元的活动。在这些神经元中，分别有 37、39 和 37 个神经元对至少一个刺激有反应。我们对来自这些核团的神经元群体反应进行了聚类分析，并从每个神经元群体中计算了关于三个类别和猴子身份的信息。我们发现，通过杏仁核的输出门中央核的神经元反应，而不是通过外侧核和基底核的神经元反应，可以更恰当地对三个类别和猴子身份进行分类。这些结果表明，关于适合产生适当情绪反应的物体的信息是通过从外侧核到中央核的杏仁核内网络在灵长类动物杏仁核中建立起来的。
