[The behavior of the b-wave in the electroretinogram of light-adapted frogs during serial light exposure]

In light-adapted frogs (adaptation luminance 10(3) asb) repeated flashes of high intensity (10(5) asb) caused decrease of the b-wave in the electroretinogram as compared to the results obtained with dark-adapted animals. The amplitude changes were monotonous in all cases; they were dependent on the spacing and duration of the stimulus. With short intervals (2-10 sec) the amplitude adjusted to a new level no later than after 8 flashes. With longer intervals (30 and 60 sec), however, the amplitude decreased slowly and steadily over the whole period of experiment. Under these conditions, adjustment to a new level was prevented by disturbing factors, which additionally reduced the retinal sensitivity depending on the duration of the experiment.