Data from: Activity patterns of serotonin neurons underlying cognitive flexibility

Serotonin is implicated in mood and affective disorders. However, growing evidence suggests that a core endogenous role is to promote flexible adaptation to changes in the causal structure of the environment, through behavioral inhibition and enhanced plasticity. We used long-term photometric recordings in mice to study a population of dorsal raphe serotonin neurons, whose activity we could link to normal reversal learning using pharmacogenetics. We found that these neurons are activated by both positive and negative prediction errors, and thus report signals similar to those proposed to promote learning in conditions of uncertainty. Furthermore, by comparing the cue responses of serotonin and dopamine neurons, we found differences in learning rates that could explain the importance of serotonin in inhibiting perseverative responding. Our findings show how the activity patterns of serotonin neurons support a role in cognitive flexibility, and suggest a revised model of dopamine–serotonin opponency with potential clinical implications.

五羟色胺（Serotonin）与情绪及情感障碍密切相关。然而，越来越多的研究证据表明，其核心内源性功能是通过行为抑制与增强突触可塑性，促进机体对环境因果结构的变化做出灵活适应。本研究利用小鼠长期光纤光度记录技术，对中缝背核五羟色胺神经元群体进行了研究，并通过药物遗传学手段将该神经元的活动与正常逆转学习建立了功能关联。研究发现，此类神经元可被正向与负向预测误差共同激活，其所传递的信号与不确定性条件下促进学习的信号特征高度相似。此外，通过对比五羟色胺神经元与多巴胺神经元的线索响应特征，本研究发现二者在学习速率上存在显著差异，该差异可解释五羟色胺在抑制持续性反应中的重要作用。本研究结果阐明了五羟色胺神经元的活动模式如何支撑其在认知灵活性中的功能，并提出了修订版的多巴胺-五羟色胺拮抗模型，该模型具备潜在的临床应用价值。