THE PERSISTENCE OF MENTAL IMPAIRMENT FOLLOWING A HYPNOTIC DOSE OF A BARBITURATE

¹ The Anesthesia Laboratory of the Harvard Medical School at the Massachusetts General Hospital, Boston, Massachusetts

The effect of 0.1 gm. of pentobarbital sodium on a variety of complex psychological functions has been investigated. As long as five and one-half to eight hours after ingestion of the drug and following a light breakfast, significant impairment of visual perception, attention, arithmetical performance, and recall was demonstrated. Associations were increased in number after drug administration, but these were less "reality determined", i.e., showed less relation to external stimuli than after the placebo: In a confusing and disturbing test situation, the drug effect was to facilitate resistance to distraction. Serial learning and an "analogies" test failed to show drug effect.

These findings are offered as objective confirmation of the frequent complaint of "hangover" after the use of pentobarbital sodium in ordinary hypnotic dose. It is suggested that the prolonged effects detected here must be considered as factors which limit the usefulness of this and similar agents when such persistence of effect might be undesirable; that is, where it is important that the individual's full mental faculties be available.