摘要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 B0wave. 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.