Abstract

Much evidence links the a-wave feature of the gross electroretinogram (ERG) to receptor function and it has been well accepted since the work of Penn and Hagins in 1969 that the a-wave is generated by the summated photocurrents of the individual photoreceptors. However, up to the present, it has not been possible to separate the ERG waveform into components such that the component attributed to receptoral activity (a-wave) exhibits the parametric behavior known to occur for the photocurrent of isolated rod photoreceptors in response to very brief light flashes. In the analysis that follows, we present evidence in support of a component schema of a-wave and b-wave representation within the gross ERG waveform that identifies the features of an a-wave component in essential agreement with the major known parametric features of receptor photocurrent response. We also identify several important b-wave features not previously described.

© 1990 Optical Society of America