Color selectivity of neurons in the posterior inferior temporal cortex of the macaque monkey

Cereb Cortex. 2010 Jul;20(7):1630-46. doi: 10.1093/cercor/bhp227. Epub 2009 Oct 30.

Abstract

We recorded the activities of neurons in the lateral surface of the posterior inferior temporal cortex (PIT) of 3 hemispheres of 3 monkeys performing a visual fixation task. We characterized the color and shape selectivities of each neuron, mapped its receptive field (RF), and studied the distributions of these response properties. Using a set of color stimuli that were systematically distributed in Commission Internationale de l'Eclairage-xy chromaticity diagram, we found numerous color-selective neurons distributed throughout the area examined. Neurons in the ventral region tended to have sharper color tuning than those in the dorsal region. We also found a crude retinotopic organization in the ventral region. Within the ventral region of PIT, neurons in the dorsal part had RFs that overlapped the foveal center; the eccentricity of RFs increased in the more ventral part, and neurons in the anterior and posterior parts had RFs that represented the lower and upper visual fields, respectively. In all 3 hemispheres, the region where sharply tuned color-selective neurons were concentrated was confined within this retinotopic map. These findings suggest that PIT is a heterogeneous area and that there is a circumscribed region within it that has crude retinotopic organization and is involved in the processing of color.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology*
  • Analysis of Variance
  • Animals
  • Brain Mapping
  • Choice Behavior / physiology*
  • Color Perception / physiology*
  • Macaca fascicularis / anatomy & histology*
  • Macaca fascicularis / physiology
  • Neurons / physiology*
  • Pattern Recognition, Visual / physiology
  • Photic Stimulation / methods
  • Reaction Time / physiology
  • Temporal Lobe / cytology*
  • Temporal Lobe / physiology
  • Time Factors
  • Visual Fields
  • Visual Pathways / physiology