Department of Physics, Pennsylvania State University, 104 Davey Laboratory, PMB 206, University Park, PA 16802, USA.
Proc Natl Acad Sci U S A. 2009 Nov 10;106(45):19156-61. doi: 10.1073/pnas.0909881106. Epub 2009 Oct 22.
Encoding time is universally required for learning and structuring motor and cognitive actions, but how the brain keeps track of time is still not understood. We searched for time representations in cortico-basal ganglia circuits by recording from thousands of neurons in the prefrontal cortex and striatum of macaque monkeys performing a routine visuomotor task. We found that a subset of neurons exhibited time-stamp encoding strikingly similar to that required by models of reinforcement-based learning: They responded with spike activity peaks that were distributed at different time delays after single task events. Moreover, the temporal evolution of the population activity allowed robust decoding of task time by perceptron models. We suggest that time information can emerge as a byproduct of event coding in cortico-basal ganglia circuits and can serve as a critical infrastructure for behavioral learning and performance.
编码时间普遍是学习和构建运动和认知行为所必需的，但大脑如何计时仍不清楚。我们通过记录猕猴执行常规视觉运动任务的前额叶皮层和纹状体中的数千个神经元，在皮质基底神经节回路中寻找时间表示。我们发现，一小部分神经元表现出与强化学习模型要求非常相似的时间戳编码：它们的尖峰活动峰值在单个任务事件后以不同的时间延迟分布。此外，群体活动的时间演化允许通过感知器模型对任务时间进行稳健解码。我们认为，时间信息可以作为皮质基底神经节回路中事件编码的副产品出现，并作为行为学习和表现的关键基础设施。
