Werner Reichardt Center for Integrative Neuroscience, 72076 Tuebingen, Germany.
Annu Rev Neurosci. 2012;35:463-83. doi: 10.1146/annurev-neuro-062111-150403. Epub 2012 Apr 5.
Neurons in early sensory cortex show weak but systematic correlations with perceptual decisions when trained animals perform at psychophysical threshold. These correlations are observed across repeated presentations of identical stimuli and cannot be explained by variation in external factors. The relationship between the activity of individual sensory neurons and the animal's behavioral choice means that even neurons in early sensory cortex carry information about an upcoming decision. This relationship, termed choice probability, may reflect the effect of fluctuations in neuronal firing rate on the animal's decision, but it can also reflect modulation of sensory responses by cognitive factors, or network properties such as variability that is shared among populations of neurons. Here, we review recent work clarifying the relationship among fluctuations in the responses of individual neurons, correlated variability, and behavior in a variety of tasks and cortical areas. We also discuss the possibility that choice probability may in part reflect the influence of cognitive factors on sensory neurons and explore the situations in which choice probability can be used to make inferences about the role of particular sensory neurons in the decision-making process.
早期感觉皮层中的神经元在经过训练的动物在感觉阈限时进行感知决策时，表现出微弱但系统的与感知决策相关的活动。这些相关性在相同刺激的重复呈现中是可以观察到的，并且不能用外部因素的变化来解释。单个感觉神经元的活动与动物的行为选择之间的关系意味着，即使是早期感觉皮层中的神经元也携带有关即将到来的决策的信息。这种关系称为选择概率，它可能反映了神经元放电率的波动对动物决策的影响，但它也可能反映了认知因素对感觉反应的调制，或者是网络属性（如神经元群体之间共享的变异性）。在这里，我们回顾了最近的工作，这些工作阐明了个体神经元反应的波动、相关变异性和各种任务和皮层区域中的行为之间的关系。我们还讨论了选择概率可能部分反映认知因素对感觉神经元的影响，并探讨了在何种情况下选择概率可用于对特定感觉神经元在决策过程中的作用做出推断。
