Schultz W, Tremblay L, Hollerman J R
Institute of Physiology and Program in Neuroscience, University of Fribourg, CH-1700 Fribourg, Switzerland.
Cereb Cortex. 2000 Mar;10(3):272-84. doi: 10.1093/cercor/10.3.272.
This article reviews and interprets neuronal activities related to the expectation and delivery of reward in the primate orbitofrontal cortex, in comparison with slowly discharging neurons in the striatum (caudate, putamen and ventral striatum, including nucleus accumbens) and midbrain dopamine neurons. Orbitofrontal neurons showed three principal forms of reward-related activity during the performance of delayed response tasks, namely responses to reward-predicting instructions, activations during the expectation period immediately preceding reward and responses following reward. These activations discriminated between different rewards, often on the basis of the animals' preferences. Neurons in the striatum were also activated in relation to the expectation and detection of reward but in addition showed activities related to the preparation, initiation and execution of movements which reflected the expected reward. Dopamine neurons responded to rewards and reward-predicting stimuli, and coded an error in the prediction of reward. Thus, the investigated cortical and basal ganglia structures showed multiple, heterogeneous, partly simultaneous activations which were related to specific aspects of rewards. These activations may represent the neuronal substrates of rewards during learning and established behavioral performance. The processing of reward expectations suggests an access to central representations of rewards which may be used for the neuronal control of goaldirected behavior.
本文回顾并阐释了与灵长类动物眶额皮质中奖励预期和奖励发放相关的神经元活动，并与纹状体（尾状核、壳核和腹侧纹状体，包括伏隔核）及中脑多巴胺能神经元中放电缓慢的神经元进行了比较。在延迟反应任务执行过程中，眶额神经元表现出三种主要的与奖励相关的活动形式，即对奖励预测指令的反应、在奖励即将到来之前的预期期内的激活以及奖励之后的反应。这些激活常常基于动物的偏好区分不同的奖励。纹状体中的神经元也会因奖励的预期和检测而被激活，但除此之外还表现出与反映预期奖励的动作准备、启动和执行相关的活动。多巴胺能神经元对奖励和奖励预测刺激做出反应，并对奖励预测中的误差进行编码。因此，所研究的皮质和基底神经节结构表现出多种、异质性且部分同时发生的激活，这些激活与奖励的特定方面相关。这些激活可能代表了学习和既定行为表现过程中奖励的神经元基质。奖励预期的处理表明可以获取奖励的中枢表征，这些表征可用于对目标导向行为的神经元控制。
