Wolfson Institute for Biomedical Research and Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.
Institute of Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
Nat Neurosci. 2022 Sep;25(9):1225-1236. doi: 10.1038/s41593-022-01151-0. Epub 2022 Aug 30.
Primary sensory cortex is thought to process incoming sensory information, while decision variables important for driving behavior are assumed to arise downstream in the processing hierarchy. Here, we used population two-photon calcium imaging and targeted two-photon optogenetic stimulation of neurons in layer 2/3 of mouse primary somatosensory cortex (S1) during a texture discrimination task to test for the presence of decision signals and probe their behavioral relevance. Small but distinct populations of neurons carried information about the stimulus irrespective of the behavioral outcome (stimulus neurons), or about the choice irrespective of the presented stimulus (decision neurons). Decision neurons show categorical coding that develops during learning, and lack a conclusive decision signal in Miss trials. All-optical photostimulation of decision neurons during behavior improves behavioral performance, establishing a causal role in driving behavior. The fact that stimulus and decision neurons are intermingled challenges the idea of S1 as a purely sensory area, and causal perturbation suggests a direct involvement of S1 decision neurons in the decision-making process.
初级感觉皮层被认为处理传入的感觉信息，而对于驱动行为很重要的决策变量则被假定在处理层次结构的下游产生。在这里，我们在纹理辨别任务期间使用群体双光子钙成像和靶向小鼠初级体感皮层（S1）第 2/3 层神经元的双光子光遗传学刺激，以测试决策信号的存在并探测其行为相关性。一小部分神经元携带与行为结果无关的刺激信息（刺激神经元），或与呈现的刺激无关的选择信息（决策神经元）。决策神经元表现出在学习过程中发展的类别编码，并且在错过试验中缺乏明确的决策信号。在行为期间对决策神经元进行全光学光刺激可提高行为表现，从而在驱动行为中建立因果作用。刺激和决策神经元交织在一起的事实挑战了 S1 作为纯粹感觉区域的观点，并且因果干扰表明 S1 决策神经元直接参与决策过程。
