小柯机器人

美国范德比尔特大学Erin S. Calipari团队近期取得重要工作进展，他们研究发现伏隔核核心中的多巴胺信号介导潜在的抑制作用。这一研究成果2022年7月28日在线出版于《自然—神经科学》杂志上。

在这里，研究人员在小鼠中表明伏隔核核心中的多巴胺是由新颖的中性刺激引起的，并且随着时间的推移，这种反应的轨迹会跟踪对这些刺激的习惯。在联想学习之前习惯于新线索会减少未来的联想学习，这种现象被称为潜在抑制。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。光遗传学操纵在习惯期对提示的多巴胺反应，双向影响了未来的联想学习。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。

据介绍，调查线索和预测结果之间的关联控制行为的神经机制的研究，通常使用联想学习框架来理解行为的神经控制。这些框架并不总是考虑到新颖性对行为和未来联想学习的全部影响。

附：英文原文

Title: Dopamine signaling in the nucleus accumbens core mediates latent inhibition

Author: Kutlu, Munir Gunes, Zachry, Jennifer E., Melugin, Patrick R., Tat, Jennifer, Cajigas, Stephanie, Isiktas, Atagun U., Patel, Dev D., Siciliano, Cody A., Schoenbaum, Geoffrey, Sharpe, Melissa J., Calipari, Erin S.

Issue&Volume: 2022-07-28

Abstract: 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. Kutlu, Zachry, Melugin et al. show that dopamine in the nucleus accumbens core is evoked by novel, neutral stimuli and tracks stimulus familiarity in the absence of valence-based predictions. These signals influence the speed of future learning for familiar stimuli.

DOI: 10.1038/s41593-022-01126-1

Source: https://www.nature.com/articles/s41593-022-01126-1

Nature Neuroscience：《自然—神经科学》，创刊于1998年。隶属于施普林格·自然出版集团，最新IF：28.771
官方网址：https://www.nature.com/neuro/
投稿链接：https://mts-nn.nature.com/cgi-bin/main.plex