On Neural Correlates of Categorical Perception

The neural substrates of visual categories have been the subject of an increasing number of neurophysiological studies. Categorization tasks are often used as a tool, in these studies, to induce well-defined categories via behavioral training. Here, we highlight the important difference between the neuronal substrates underlying perceptual versus behavioral categories. To illustrate this distinction, we examine a recently reported study of the neural representation of motion categories. Using a simple model of categorical perception, we identify potential neural signatures of perceptual motion categories. Our exercise indicates that the neural correlates of categorical motion perception can be subtler than the binary response profile that is often treated as the litmus test of visual categorization.