Nusinowitz S, Hood D C, Birch D G
Retina Foundation of the Southwest, Dallas, Texas 75231, USA.
J Opt Soc Am A Opt Image Sci Vis. 1995 Oct;12(10):2259-66. doi: 10.1364/josaa.12.002259.
The analysis of electroretinogram a waves from locally stimulated populations of rods is complicated by the presence of scattered light within the eye. Scattered-light and cone contributions can be assessed after brief flashes of light designed to saturate only rods in the locally stimulated area. Subtracting the scattered-light and the cone responses from the local electroretinogram gives a pure rod a wave that can be fitted with models of photoreceptor activity. We demonstrate the feasibility of this technique by recording local rod a waves from a group of five normal subjects and by fitting the a waves with the rod model to derive transduction parameters. The local rod a waves are compared with expected responses derived from simulations in which the response of the entire retina to heterogeneous illumination is mimicked.
