The effect of quinalbarbitone on the cerebral response to flicker in man

Abstract Cerebral rhythms recorded between occiput and vertex were quantified by frequency analysis both in the resting state and during repetitive photic stimulation at frequencies from 5–30 c/sec. Measurements were made in 6 subjects before and after ingestion of quinalbarbitone (75 and 150 mg) in a controlled experiment. Without stimulation quinalbarbitone resulted only in increases in activity, particularly at the higher frequencies, and in a shift of the spectrum toward the lower frequencies. These findings confirm previous reports. The addition of photic stimulation did not result in a generalised enhancement of the drug effects obtained without stimulation. There were increases in response at frequencies below that of the mean initial peak response at 10 c/sec, but there were significant decreases at frequencies just above it. It was speculated that these effects might be attributed to a prolongation of the visual recovery function by the barbiturate. At the higher frequencies there were no significant changes in the results with stimulation in contrast to the pronounced increases in activity without stimulation.