Visual response latency of X- and Y-cells in the dorsal lateral geniculate nucleus of the cat.
Publication/Presentation Date
1-1-1986
Abstract
Visual response latencies and rise times of X- and Y-cells in the dorsal lateral geniculate nucleus (dLGN) of anaesthetized, paralyzed cats were measured during repeated stimulation with sinusoidal grating patterns. Measurements were restricted to individual stimulus trials on which the instantaneous discharge rate exceeded a criterion amplitude defined in terms of the baseline activity of each cell. The latencies of response onsets and response peaks were systematically related to the spatial frequency and contrast of the grating stimuli. Response latencies of Y-cells were shortest for gratings of low spatial frequency (0.17 c/deg) and increased monotonically with increases in spatial frequency. Response latencies of X-cells were shortest for gratings of intermediate spatial frequency (0.75 c/deg) and longer for lower and higher spatial frequencies. Latencies decreased monotonically with increases in stimulus contrast from 5 to 40% for both X- and Y-cells. In general, short-latency responses were less variable than long-latency responses. This was true for absolute as well as relative measures of variability. The mean onset and peak latencies of Y-cell responses were 10-15 msec shorter than the corresponding latencies of X-cell responses to stimuli of optimal spatial frequency and contrast. The rise times (latency of response peak minus latency of response onset) of Y-cell responses were consistently shorter than those of X-cells in spite of the higher peak responses of Y-cells. The results of this study are consistent with the idea that low spatial frequency information is passed through the lateral geniculate nucleus more quickly than is high spatial frequency information. These data provide support for models of visual processing wherein a coarse, global analysis of the visual scene by Y-cells precedes a finer, local analysis by X-cells.
Volume
26
Issue
7
First Page
1041
Last Page
1054
ISSN
0042-6989
Published In/Presented At
Sestokas, A. K., & Lehmkuhle, S. (1986). Visual response latency of X- and Y-cells in the dorsal lateral geniculate nucleus of the cat. Vision research, 26(7), 1041–1054. https://doi.org/10.1016/0042-6989(86)90038-6
Disciplines
Medicine and Health Sciences
PubMedID
3798741
Department(s)
Department of Medicine
Document Type
Article