The nervous system is hypothesized to compute reward prediction errors (RPEs) to promote adaptive behavior. Correlates of RPEs have been observed in the midbrain dopamine system, but the extent to which RPE signals exist in other reward-processing regions is less well understood. In the present study, we quantified outcome history-based RPE signals in the ventral pallidum (VP), a basal ganglia region functionally linked to reward-seeking behavior. We trained rats to respond to reward-predicting cues, and we fit computational models to predict the firing rates of individual neurons at the time of reward delivery. We found that a subset of VP neurons encoded RPEs and did so more robustly than the nucleus accumbens, an input to the VP. VP RPEs predicted changes in task engagement, and optogenetic manipulation of the VP during reward delivery bidirectionally altered rats’ subsequent reward-seeking behavior. Our data suggest a pivotal role for the VP in computing teaching signals that influence adaptive reward seeking.

假设神经系统计算奖励预测误差（RPE）以促进适应性行为。在中脑多巴胺系统中已观察到RPE的相关性，但对其他奖励处理区域中RPE信号存在的程度的了解却很少。在本研究中，我们在腹侧苍白球（VP）中定量了基于结果历史的RPE信号，该功能是与奖励寻求行为相关的基底神经节区域。我们训练了大鼠对奖励预测线索做出响应，并拟合了计算模型来预测奖励交付时单个神经元的放电速率。我们发现，VP神经元的一个子集编码RPE，并且比伏隔核（VP的输入）更强大。副总裁RPE预测了任务投入的变化，奖励传递过程中VP的光遗传学操纵和双向操纵改变了大鼠随后的奖励寻求行为。我们的数据表明VP在计算影响自适应奖励寻求的教学信号中起着关键作用。