Moment-to-moment tracking of state value in the amygdala.
Moment-to-moment tracking of state value in the amygdala.
复制标题
实时跟踪杏仁核的状态值。
DOI：
10.1523/jneurosci.1400-08.2008
复制
发表时间：
2008-10-01
影响因子：
5.3
通讯作者：
Salzman, C. Daniel
中科院分区：
文献类型：
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作者：
Belova, Marina A.;Paton, Joseph J.;Salzman, C. Daniel
As an organism interacts with the world, how good or bad things are at the moment - the value of the organism’s current state - is an important parameter that is likely to be encoded in the brain. As the environment changes and new stimuli appear, estimates of state value must be updated to support appropriate responses and learning. Indeed, many models of reinforcement learning posit representations of state value. We examined how the brain mediates this process by recording amygdala neural activity while monkeys performed a trace-conditioning task requiring fixation. The presentation of different stimuli induced state transitions; these stimuli included unconditioned stimuli (USs, liquid rewards and aversive air-puffs), newly learned reinforcement-predictive visual stimuli (conditioned stimuli, CSs), and familiar stimuli long associated with reinforcement (fixation point, FP). The FP had a positive value to monkeys, since they chose to foveate it to initiate trials. Different populations of amygdala neurons tracked the positive or negative value of the current state, regardless of whether state transitions were caused by the FP, CSs, or USs. Positive value-coding neurons increased their firing during the fixation interval, and fired more strongly after rewarded CSs and rewards than after punished CSs and air-puffs. Negative value-coding neurons did the opposite, decreasing their firing during the fixation interval and firing more strongly after punished CSs and air-puffs than after rewarded CSs and rewards. This representation of state value could underlie how the amygdala helps coordinate cognitive, emotional, and behavioral responses depending upon the value of one’s state.
