Accession Number : ADA112802

Title :   Visual Acuity and Its Dependence Upon Receptor Density and Retinal Ganglion Cell Receptive Field Overlap.

Descriptive Note : Final rept.,


Personal Author(s) : Wolbarsht,Myron L ; Ringo,James

Full Text :

Report Date : Nov 1981

Pagination or Media Count : 40

Abstract : The organization of the retina was investigated with regard to visual acuity. In particular, the receptive fields of the ganglion cells were analyzed and described in terms of, primarily, their anatomical relations to each other, i.e., receptor spacing and secondly, the neural organization. In a typical eye (cat) the sensitivity to angular separation on the basis of anatomical makeup has an upper limit of 8 cycles per degree for acuity. On the other hand, it is predicted that, for neural processing of overlapping ganglion cell receptive fields in the retina, the behavioral response should be at least twice as good, i.e., approximately 16 cycles per degree. The different methods of analyzing receptive fields compare the sensitivity of the receptors with a static stimulus (sensitivity profile and Ricco field - area x intensity - test), and displacement sensitivity (the response to a small stimulus spot switched between the two positions just touching each other). Present data, which indicates that in the area of high sensitivity in the cat retina at least 15 receptive field centers must overlap, leads to the conclusion that the retinal visual acuity is not limited by the receptive field size, but rather displacement sensitivity and the processing of the information by higher visual centers.

Descriptors :   *Visual acuity , Density , Retina , Ganglia , Sensitivity , Displacement , Cats

Subject Categories : Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE