Studies investigating the neural mechanisms by which associations between cues and predicted outcomes control behavior often use associative learning frameworks to understand the neural control of behavior. These frameworks do not always account for the full range of effects that novelty can have on behavior and future associative learning. Here, in mice, we show that dopamine in the nucleus accumbens core is evoked by novel, neutral stimuli, and the trajectory of this response over time tracked habituation to these stimuli. Habituation to novel cues before associative learning reduced future associative learning, a phenomenon known as latent inhibition. Crucially, trial-by-trial dopamine response patterns tracked this phenomenon. Optogenetic manipulation of dopamine responses to the cue during the habituation period bidirectionally influenced future associative learning. Thus, dopamine signaling in the nucleus accumbens core has a causal role in novelty-based learning in a way that cannot be predicted based on purely associative factors.

研究线索和预测结果之间的关联控制行为的神经机制通常使用联想学习框架来理解行为的神经控制。这些框架并不总能考虑新颖性对行为和未来联想学习产生的全方位影响。在这里，我们在小鼠身上发现，伏隔核核心中的多巴胺是由新的中性刺激引起的，并且随着时间的推移，这种反应的轨迹跟踪了对这些刺激的习惯。在联想学习之前对新线索的习惯会减少未来的联想学习，这种现象称为潜在抑制。至关重要的是，逐次试验的多巴胺反应模式追踪了这一现象。在习惯化期间，多巴胺对提示的反应的光遗传学操纵双向影响未来的联想学习。因此，伏隔核核心中的多巴胺信号传导在基于新颖性的学习中具有因果作用，其方式无法基于纯粹的关联因素进行预测。