期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2015
卷号：112
期号：15
页码：4773-4778
DOI：10.1073/pnas.1504723112
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceA key step in studying perceptual categorization mechanisms is to understand how neurons from early sensory cortices encode the relevant features categorized of a sensory stimulus and how they relate to it. We studied the encoding capacities of primary somatosensory cortex (S1) neurons while trained monkeys categorized only one sensory feature of a vibrotactile stimulus: frequency, amplitude, or duration. The results suggest a hierarchical encoding scheme in S1: from neurons that encode all sensory features of the vibrotactile stimulus to neurons that encode only one sensory feature. Sensory feature encoding in S1 could serve downstream networks for constructing perceptual categorization. Neurons of the primary somatosensory cortex (S1) respond as functions of frequency or amplitude of a vibrotactile stimulus. However, whether S1 neurons encode both frequency and amplitude of the vibrotactile stimulus or whether each sensory feature is encoded by separate populations of S1 neurons is not known, To further address these questions, we recorded S1 neurons while trained monkeys categorized only one sensory feature of the vibrotactile stimulus: frequency, amplitude, or duration. The results suggest a hierarchical encoding scheme in S1: from neurons that encode all sensory features of the vibrotactile stimulus to neurons that encode only one sensory feature. We hypothesize that the dynamic representation of each sensory feature in S1 might serve for further downstream processing that leads to the monkey's psychophysical behavior observed in these tasks.
