The influence of adaptation on DC-component of human electroretinogram

The effect of light stimulus intensity and background light illumination on human DC-electroretinogram-(ERG) was measured over a wide range. The DC-component, which followed the B-wave, could be recorded by a long lasting light stimulus with DC-recording (direct coupling). The DC-component showed in comparison to the base line positive or negative values depending on the stimulus intensity. The DC-component rose with increasing light stimulus intensities and fell with increasing background light luminances. When the amplitudes of the DC-component to serial stimulus intensities and different background luminances showed responses different to those of the A-wave, they had similar properties to those of B-wave. The site of the "neural" adaptation in vision may be located in the inner retinal layers, from which both DC-component and B-wave originate.