Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, Building 49, MSC 4415, 49 Convent Drive, Bethesda, MD 20892-4415, USA.
Curr Opin Neurobiol. 2010 Apr;20(2):212-20. doi: 10.1016/j.conb.2010.02.001. Epub 2010 Feb 22.
Recent research indicates that the orbital prefrontal cortex (PFo) represents stimulus valuations and that the amygdala updates these valuations. An exploration of how PFo and the amygdala interact could improve the understanding of both. PFo and the amygdala function cooperatively when monkeys choose objects associated with recently revalued foods. In other tasks, they function in opposition. PFo uses positive feedback to promote learning in object-reward reversal tasks, and PFo also promotes extinction learning. Amygdala function interferes with both kinds of learning. The amygdala underlies fearful responses to a rubber snake from the first exposure on, but PFo is necessary only after the initial exposure. The amygdala mediates an arousal response in anticipation of rewards, whereas PFo sometimes suppresses such arousal. A role for PFo in advanced cognition, for the amygdala in instinctive behavior, and for cortex-subcortex interactions in prioritizing behaviors provides one account for these findings.
最近的研究表明，眶额前皮质（PFo）代表刺激价值，而杏仁核则更新这些价值。探索 PFo 和杏仁核如何相互作用，可以增进对两者的理解。当猴子选择与最近重新评估的食物相关的物体时，PFo 和杏仁核会协同作用。在其他任务中，它们则作用相反。PFo 利用正反馈来促进物体奖励反转任务中的学习，并且 PFo 还促进消退学习。杏仁核的功能会干扰这两种学习。杏仁核对从第一次暴露开始的橡胶蛇的恐惧反应是基础，但 PFo 只在最初暴露后才是必要的。杏仁核对奖励的预期产生唤醒反应，而 PFo 有时会抑制这种唤醒。PFo 在高级认知中的作用，杏仁核在本能行为中的作用，以及皮层-皮层下相互作用在优先行为中的作用，为这些发现提供了一种解释。
