Some observations on the c-wave of the electroretinogram in the intact frog eye

A cone-triggered c-wave in the chicken ERG time integration characteristics

The c-waves recorded from the cone-dominant retina of the chicken proved to be cone-triggered. The time course and time integration properties of this retinal potential were compared with those of the rod-triggered c-wave recorded in the frog under scotopic conditions. The results clearly demonstrate that there is no evidence for time integration in cone-triggered c-waves but that rod-triggered c-waves follow the Bunsen-Roscoe law over more than 2 log units. We propose that these time-related differences may be used in other species as a differentiation criterion between cone-triggered and rod-triggered c-waves.

Evidence for both photopic and scotopic characteristics in the c-wave of chicken and frog ERG

The electroretinographic c-wave was studied in two species with duplex retinas, the frog (rod-dominant) and the chicken (highly cone-dominant). In both species a cone driven c-wave was recorded in addition to the classical rod-driven c-wave. An attempt was made to specify the differential characteristics with respect to time-course, time integration, adaptational changes and spectral sensitivity of cone-driven vs rod-driven c-waves. These data confirm the generality of the c-wave generation by both rod and cone systems.