Thompson John A, Costabile Jamie D, Felsen Gidon
Department of Neurosurgery, University of Colorado School of Medicine, Aurora, United States.
Department of Physiology and Biophysics, University of Colorado School of Medicine, Aurora, United States.
Elife. 2016 Jul 25;5:e16572. doi: 10.7554/eLife.16572.
Decisions are influenced by recent experience, but the neural basis for this phenomenon is not well understood. Here, we address this question in the context of action selection. We focused on activity in the pedunculopontine tegmental nucleus (PPTg), a mesencephalic region that provides input to several nuclei in the action selection network, in well-trained mice selecting actions based on sensory cues and recent trial history. We found that, at the time of action selection, the activity of many PPTg neurons reflected the action on the previous trial and its outcome, and the strength of this activity predicted the upcoming choice. Further, inactivating the PPTg predictably decreased the influence of recent experience on action selection. These findings suggest that PPTg input to downstream motor regions, where it can be integrated with other relevant information, provides a simple mechanism for incorporating recent experience into the computations underlying action selection.
决策会受到近期经历的影响，但其背后的神经机制尚未被完全理解。在此，我们在行动选择的背景下探讨这一问题。我们聚焦于脚桥被盖核（PPTg）的活动，它是中脑的一个区域，为行动选择网络中的多个核团提供输入，实验对象是经过良好训练的小鼠，它们基于感官线索和近期的试验历史来选择行动。我们发现，在行动选择时，许多PPTg神经元的活动反映了前一次试验的行动及其结果，并且这种活动的强度预测了即将做出的选择。此外，抑制PPTg可预见地降低了近期经历对行动选择的影响。这些发现表明，PPTg向其可以与其他相关信息整合的下游运动区域的输入，为将近期经历纳入行动选择背后的计算提供了一种简单机制。
