Perceptual categorization depends on the assignment of different stimuli to specific groups based, in principle, on the notion of flexible categorical boundaries. To determine the neural basis of categorical boundaries, we record the activity of pre-SMA neurons of monkeys executing an interval categorization task in which the limit between short and long categories changes between blocks of trials within a session. A large population of cells encodes this boundary by reaching a constant peak of activity close to the corresponding subjective limit. Notably, the time at which this peak is reached changes according to the categorical boundary of the current block, predicting the monkeys' categorical decision on a trial-by-trial basis. In addition, pre-SMA cells also represent the category selected by the monkeys and the outcome of the decision. These results suggest that the pre-SMA adaptively encodes subjective duration boundaries between short and long durations and contains crucial neural information to categorize intervals and evaluate the outcome of such perceptual decisions.

中文翻译：

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时间间隔相对分类期间灵长类 SMA 前的分类边界的神经基础。


感知分类取决于原则上基于灵活分类边界的概念将不同刺激分配给特定组。为了确定分类边界的神经基础，我们记录了执行区间分类任务的猴子的前 SMA 神经元的活动，其中短类别和长类别之间的限制在会话内的试验块之间发生变化。大量细胞通过达到接近相应主观极限的恒定活动峰值来编码该边界。值得注意的是，达到该峰值的时间根据当前块的分类边界而变化，从而在逐次试验的基础上预测猴子的分类决策。此外，前SMA细胞还代表了猴子选择的类别和决策的结果。这些结果表明，前 SMA 自适应地编码短持续时间和长持续时间之间的主观持续时间边界，并包含对间隔进行分类和评估此类感知决策结果的关键神经信息。