Chapter

Color Vision

Nigel Daw

in How Vision Works

Published in print January 2012 | ISBN: 9780199751617
Published online May 2012 | e-ISBN: 9780199932375 | DOI: http://dx.doi.org/10.1093/acprof:oso/9780199751617.003.0004
Color Vision

Show Summary Details

Preview

Color vision is trichromatic, as a result of three kinds of cone photoreceptors with different spectral sensitivities. The output of the long-wavelength cones is subtracted from the output of the middle wavelength cones to give a red/green opponent color signal in the retina, and another subtraction in different cells gives a yellow/blue opponent color signal. These signals are conveyed to the lateral geniculate nucleus without much change, then to V1, where double opponent (opponent for color in the center of the receptive field, with the opposite sign of response in the surround) cells are found in upper layers in what are called blobs. The blobs project to the thin stripes in V2, then to clusters of color-coded cells in V4, and to inferotemporal cortex. Lack of one type of cone leads to color blindness, and lesions near V4 leads to achromatopsia.

Keywords: color vision; trichromatic; opponent colors; double opponent cells; blobs; v4; inferotemporal cortex; color blindness; achromatopsia

Chapter.  7865 words.  Illustrated.

Subjects: Neuropsychology

Full text: subscription required

How to subscribe Recommend to my Librarian

Buy this work at Oxford University Press »

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.