During clinical electroretinographic examination of patients we observed a new phenomenon which we called "exhaustion phenomenon" (phénomène d'épuisement). This phenomenon has been further studied in cats.
Briefly, it is as follows: If the darkadapted cat retina is stimulated intermittently with light of 50 lux intensity (measured at the cornea), one-tenth second duration, and one second frequency, the b-potential in the ERG is practically the same for each stimulus. If, however, the procedure is repeated on a cat with impaired oxygen supply, the b-potentials on intermittent stimulation become progressively smaller and finally may almost disappear. If the intermittent stimulation is now suspended for a time, e. g., one minute, while the cat still remains in darkness, the b-potential will be found to have returned to its former level, but on intermittent stimulation it will again become smaller. We ascribed this phenomenon to a delayed recovery of the adaption state in hypoxemia.
HORSTEN GPM, WINKELMAN JE. Effect of Temporary Occlusion of the Aorta on the Electroretinogram. AMA Arch Ophthalmol. 1957;57(4):557–565. doi:10.1001/archopht.1957.00930050569010
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