Electroretinogram and visually evoked cortical potential in Tay-Sachs disease: a report of two cases

The electroretinogram (ERG) and visually evoked cortical potential (VECP) were recorded in two cases of Tay-Sachs disease where diagnosis was well established: 1. ERGs of high amplitude and of normal wave form were recordable with prominent oscillatory potentials. Responses were always equal in both eyes. 2. VECPs were extinguished in both cases. These findings were interpreted as showing that Tay-Sachs disease is caused by the degeneration of ganglion cells in the nervous system and that the ganglion cells in the retina do not affect the ERGs of vertebrate animals.