Wilson David I G, Bowman E M
School of Psychology, University of St. Andrews, St. Mary's Quadrangle, South Street, St. Andrews, Fife, Scotland KY16 9JP, UK.
J Neurophysiol. 2005 Jul;94(1):49-61. doi: 10.1152/jn.01332.2004. Epub 2005 Mar 2.
It has been proposed that nucleus accumbens neurons respond to outcome (reward and punishment) and outcome-predictive information. Alternatively, it has been suggested that these neurons respond to salient stimuli, regardless of their outcome-predictive properties, to facilitate a switch in ongoing behavior. We recorded the activity of 82 single-nucleus accumbens neurons in thirsty rats responding within a modified go/no-go task. The task design allowed us to analyze whether neurons responded to conditioned stimuli that predicted rewarding (saccharin) or aversive (quinine) outcomes, and whether the neural responses correlated with behavioral switching. Approximately one third (28/82) of nucleus accumbens neurons exhibited 35 responses to conditioned stimuli. Over 2/3 of these responses encoded the nature of the upcoming rewarding (19/35) or aversive (5/35) outcome. No response was selective solely for the switching of the rat's behavior, although the activity of approximately one third of responses (11/35) predicted the upcoming outcome and was correlated with the presence or absence of a subsequent behavioral switch. Our data suggest a primary functional role for the nucleus accumbens in encoding outcome-predicting information and a more limited role in behavioral switching.
有人提出，伏隔核神经元对结果（奖励和惩罚）以及结果预测信息有反应。另一种观点认为，这些神经元对显著刺激有反应，而不管其结果预测特性如何，以促进正在进行的行为的转换。我们在经过改良的“去/不去”任务中记录了82只口渴大鼠伏隔核单神经元的活动。该任务设计使我们能够分析神经元是否对预测奖励（糖精）或厌恶（奎宁）结果的条件刺激有反应，以及神经反应是否与行为转换相关。大约三分之一（28/82）的伏隔核神经元对条件刺激有反应。其中超过三分之二的反应编码了即将到来的奖励（19/35）或厌恶（5/35）结果的性质。没有反应仅对大鼠行为的转换具有选择性，尽管大约三分之一的反应（11/35）的活动预测了即将到来的结果，并与随后行为转换的存在或不存在相关。我们的数据表明，伏隔核在编码结果预测信息方面具有主要功能作用，而在行为转换方面的作用较为有限。
