THE GEOMETRICAL ANALYSIS OF THE PHOTOPIC CORNEAL ERG. I. ON- AND OFF-RESPONSES,
Abstract
The corneal ERG of the response to a photopic stimulus in the frog shows five potential changes: to ON, a small rapid negative (I), a large rapid positive (II), and a slow negative (III); to OFF, a large rapid positive (IV) and a slow negative (V). When stimulus intervals are sufficiently long, the negative potentials III and V return to the zero resting potential. The temporal course of these potentials can be expressed by probability functions, in which the voltage is analogous to the normal ordinate, and the time analogous to the normal deviate. An example is developed for the condition of alternation between 8500 lux and total darkness at 2500 milliseconds of each, which shows excellent agreement between the empirical CRT trace and the derived geometrical pattern. The electronic equipment, including preparation of electrodes, the effect of filtering the amplification system, and the specifications of the stimulator are discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 19, 1960
- Accession Number
- AD0619230
Entities
People
- Robert H. Peckham
- William M. Hart