Oscillatory potentials as predictors to amplitude and peak time of the photopic b-wave of the human electroretinogram

Abstract

The oscillatory potentials are viewed by many as small oscillations of a high-frequency domain that ride on the b-wave of the electroretinogram. A study of electroretinograms and oscillatory potentials performed in 25 normal subjects was undertaken to substantiate my claim that oscillatory potentials are fast retinal potentials that are integrated to form the b-wave. The prominence of the OPs on the ascending limb of the b-wave was found to be only weakly correlated (r = -0.37) to the amplitude of the oscillatory potentials (measured in the 100-1000 Hz recordings). There was, however, a high correlation (r = 0.78) between the prominence of the oscillatory potentials and their frequency domain as determined by the peak-to-peak timing. Furthermore, the peak-to-peak timing of the oscillatory potentials was highly correlated with the b-wave peak time (r = 0.86) as well as with the 'a-wave trough to b-wave peak' time (r = 0.90), while the amplitude of the oscillatory potentials was correlated to the amplitude of the b-wave (r = 0.78). Interestingly, when combining the amplitude of the oscillatory potentials with the time interval between oscillatory potentials 2 and 3 and 3 and 4, a higher correlation (r = 0.88) was found with the b-wave amplitude. The latter finding would support my claim that the b-wave represents an integration (amplitude as a function of time) of the oscillatory potentials.