Response: Towards a neural representation for unique hues

Abstract

We recently reported that a population of color-tuned neurons in posterior inferior temporal cortex of macaque monkey represents all colors and that this population shows a bias towards certain colors: we found that many cells were tuned to red, followed by peaks to green, blue, and an indistinct peak corresponding to yellow [1]. This appears to be the closest explicit neural representation of unique hues found in the primate. John Mollon suggests that the distribution is what one would expect of neurons found earlier in the visual pathway, in lateral geniculate nucleus (LGN), if tested with the colors we used to measure tuning. Previous work has shown that LGN cells respond linearly to changes in cone contrast and do not represent unique hues. While we acknowledge that our stimuli would constrain the population's color-tuning distribution if the neurons were linear, the recorded cells have narrow nonlinear color tuning, quite unlike LGN cells. Thus, the population tuning is consistent with our initial interpretation. © 2009 Elsevier Ltd. All rights reserved.