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Abstract #27731 Published in IGR 13-1
Responses of Primate Retinal Ganglion Cells to Perimetric Stimuli
Swanson WH; Sun H; Lee BB; Cao DInvestigative Ophthalmology and Visual Science 2011; 52: 764-771
Purpose. Perimetry is used clinically to assess glaucomatous ganglion cell loss. It has been proposed that frequency-doubling stimuli are better than the conventional size III perimetric stimulus in preferentially stimulating magnocellular (M) versus parvocellular (P) ganglion cells. However, little is known about how primate ganglion cells respond to perimetric stimuli. The authors recorded contrast responses of M and P ganglion cells to size III and frequency-doubling stimuli and compared contrast gain of M and P cells to these stimuli to assess the ability of these stimuli to preferentially stimulate M versus P cells. Methods. Data were recorded from 69 macaque retinal ganglion cells, by an in vivo preparation, at eccentricities of 5° to 15°. The size III stimulus was a circular luminance increment 26 min arc in diameter, 200 ms in duration. The frequency-doubling stimulus was a sinusoidal grating (0.5 cyc/deg) temporally modulated in counterphase at 13 Hz. A Michaelis-Menten function was fit to each cell's contrast responses to assess contrast gain. Results. For both size III and frequency-doubling stimuli, ganglion cell responses increased linearly at low contrasts, and then the increase slowed at high contrasts (saturation). The mean (± SE) difference in estimated log contrast gain between M and P cells for the size III stimulus was significantly higher than that for the frequency-doubling stimulus (1.24 ± 0.09 vs. 0.89 ± 0.13; P < 0.01). Conclusions. The size III stimulus was superior to the frequency-doubling stimulus in preferentially stimulating M cells versus P cells.
Classification:
5.2 Primates (Part of: 5 Experimental glaucoma; animal models)
6.6.3 Special methods (e.g. color, contrast, SWAP etc.) (Part of: 6 Clinical examination methods > 6.6 Visual field examination and other visual function tests)
2.13 Retina and retinal nerve fibre layer (Part of: 2 Anatomical structures in glaucoma)
