What role do the parallel chanels of the retina play in the processing of stereopsis and motion parallax?

V.S. Weiner and P.H. Schiller, 2006
Soc Neurosci. Abstr., 801.13.

Abstract
Previous work has established that the parasol retinal ganglion cells in the primate retina receive convergent input from the red, green and blue cones, have dendritic arbors and receptive fields three times those of midget cells, and are not capable of processing information at high spatial frequencies (Schiller & Logothetis, TINS, 1990, 13, 292-398). Research has also shown that the midget and koniocellular cells of the retina break down color information along two major axes, the red/green and the blue/yellow (Derrington, Krauskopf & Lennie, J. Physiol, 1984, 357, 241-265).
We have developed a random-dot display that can provide disparity and motion parallax cues separately or in combination and can, in addition, be set up to not activate the parasol system and to selectively drive the red/green or the blue yellow channels that originate in the retina. Using this system with rhesus monkeys as subjects, we were able to determine the role the midget, parasol and koniocellular systems play in stereopsis and in motion parallax.
The parasol system was rendered unresponsive by using high spatial frequency isoluminant random dot displays. When this was done, performance of the animals was greatly attenuated on the motion parallax task but was unaffected on the disparity task. These findings suggests that in monkeys the parasol system plays a central role in the processing of motion parallax information.
The red/green and blue/yellow axes in our experiments were selectively activated by presenting cone isolating stimulus displays at isoluminance. When this was done, performance of the monkeys on the disparity task remained outstanding with red/green isoluminant displays, but became significantly impaired using isolumiant blue/yellow stimuli of comparable color contrast. These findings suggest that the red/green midget cells of the retina play a central role in processing stereopsis and that the blue/yellow midget and koniocellular cells play a minor role in this process.


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Citation: V.S. Weiner and P.H. Schiller What role do the parallel chanels of the retina play in the processing of stereopsis and motion parallax? Program No. 801.13. 2006 Neuroscience Meeting Planner. Atlanta, GA: Society for Neuroscience, 2006. Online.



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