NATURE OF EFFICIENCY DECREMENT PRODUCED BY NITROUS OXIDE ON MONKEYS IN A VISUAL DISCRIMINATION AND DELAYED RESPONSE TEST

¹ Department of Pharmacology, Albert Einstein College of Medicine, New York, New York

A mixture of 80% nitrous oxide in oxygen was administered to five monkeys while they were working for a liquid reward in a visual discrimination and delayed response situation. Animals had to discriminate a neon figure "3" from a "4" in one test and had to delay a response for 2 seconds in the other. Both accuracy and total response rate were depressed by nitrous oxide, but there were no consistent differences between effects upon visual discrimination and upon delayed response. There was a marked increase in perseverative errors with the drug. Nitrous oxide produces impairment of discriminative behavior as well as general depression at the highest concentration compatible with normal oxygen intake.