A comparative study of b- and d-waves of the electroretinogram, in frogs (Rana catesbeiana).

The aim of this study was to compare the b- and d-waves of the ERG, evoked respectively by ON and OFF stimuli. The experiments were carried out on frogs. The d-wave is facilitated by light adaptation and relatively high stimulus intensity. The depth profiles of b- and d-waves are different. Aspartic acid abolished only the b-wave whereas nembutal affected the d-wave. These results suggested that b- and d-waves were produced by separate neuronal mechanisms, even though both appeared as positive deflection in the corneal ERG and were sensitive to K+ ion.