Nonlinearties in the Electroretinogram

The intraretinal electroretinogram is investigated utilizing a systems analysis approach to its evaluation. Complex stimuli are employed to elicit both the transient and steady state response of the retina to light. Extraction of the response is over tungsten microelectrodes and dc amplification with appropriate impedance matching characteristics in the input stage and data averaging technqiues. The system response is discussed in terms of its linear and nonlinear content. From dynamic considerations specific characteristics are noted such as asymmetrical rectification with the on‐channel having an amplitude response greater than the off‐channel and different latencies and temporal characteristics. Neither channel exhibits a dc response. The steady state frequency response provides band width information and the rate of attention at higher frequencies. At low frequencies the harmonic content is large and diminishes with increasing frequency. The presence of nonlinear components is discussed in terms of retinal anatomy.