EFFECTS OF NITRAZEPAM AMYLOBARBITONE AND PLACEBO ON SOME PERCEPTUAL MOTOR AND COGNITIVE TASKS IN NORMAL SUBJECTS

Some behavioural effects of placebo, 5 and 10 mg of nitrazepam and 100 and 200 mg of sodium amylobarbitone were compared in 10 healthy young subjects. Both doses of nitrazepam had a more pronounced effect upon measures of motor response time, decision time and digit symbol substitution than either dose of the barbiturate, but the effects of the benzodiazepine were probably diminishing at a time (150 min after drug administration) when those of the barbiturate were still increasing. Nitrazepam markedly increased the latency of after-image development and reduced its duration. There was a tendency for an increased information load to slow decision time more when subjects were treated with sodium amylobarbitone than with nitrazepam. Comparison of performance under placebo of subjects who did and did not sleep when treated with 10 mg nitrazepam suggested that the effects of this dose of the drug were predominantly hypnotic for the former and tranquillizing" for the latter. © 1969 Springer-Verlag."