NEURAL MECHANISMS OF MOTIVATION AND REWARD

在我们对动机的研究中，我们发现猴子工作得更快， 更少的错误，当提示指示果汁奖励将是 在下一次正确回答后立即发送，而不是在提示时 表明将需要进行更多的试验。大脑中的单个神经元 当腹侧纹状体跟随一个或多个 没有回报的试验，从而提供了一种神经信号，可能会强化 行为复杂。神经元的反应因此直接与 复合体中线索意义的联想学习 行为任务。改变提示符的含义伴随着一个 神经活动的平行变化。具体地说，神经元跟踪 关于动物是在开始、结束还是在一个 最终导致奖励的行为序列。这些神经元 静脉注射可卡因作为奖励时的反应不同 来自那些对果汁有反应的人，他们的反应同样强烈 无论试验是否获得奖励，表明神经元反应 与可卡因相关的不仅仅是增强的正常信号，而是 在性质上不同。

In our studies of motivation, we have found that monkeys work faster and with fewer errors when a cue indicates that a juice reward will be delivered immediately after the next correct response than when the cue indicates that additional trials will be needed. Single neurons in the ventral striatum signal the rewarded trial when it follows one or more unrewarded trials, thus providing a neural signal that could reinforce complex behavior. The neuronal responses are thus directly related to the associative learning of the meaning of the cue in a complex behavioral task. Changing the meaning of the cue is accompanied by a parallel change in neural activity. Specifically, the neurons keep track of whether the animal is at the beginning, end, or in the course of a behavioral sequence that ultimately leads to reward. The neurons that responded when intravenous cocaine was used as the reward were different from those that responded to juice, and they responded equally strongly whether the trial was rewarded or not, indicating that neuronal responses related to cocaine are not simply enhanced normal signals, but are qualitatively different.