Cognitive performance in light current users and ex-users of ecstasy (MDMA) and controls.

Previous research has shown that heavy users of ecstasy (MDMA) may suffer impaired cognitive functioning, and the present study set out to investigate whether such impairment might also be found in light users or ex-users of MDMA. Sixty subjects, comprising 20 current light users, 20 ex-users, and 20 non-users of ecstasy, were tested on an extensive battery of cognitive tests. Current light users of ecstasy achieved significantly lower scores on the overall cognitive test battery than did the non-users (p = .011), though there were no significant differences on any individual subtests. However, the scores obtained by the ex-users of ecstasy did not differ significantly from those of the non-users. It was concluded that current light users of ecstasy show a small but significant cognitive impairment, but that no such impairment is detectable in ex-users who had abstained from the drug for at least 6 months.

Memory test performance under three different waveforms of ECT for depression.

Thirty-eight patients suffering from severe depression were given a course of ECT (Electroconvulsive therapy) in one of three waveforms. These were high-energy sine wave (HS), high-energy pulse (HP), and low-energy pulse (LP). Patients were assigned to one of these treatments on a double-blind basis. The patients were given a battery of memory tests before ECT commenced, after three treatments, at the termination of treatment, and two weeks after the last treatment. The marked improvement in both verbal and nonverbal memory scores was attributed to the lifting of depression. No significant differences were found between the memory scores of the three treatment groups at any point during the treatment period.

The effect of memory impairment on verbal recognition scores and the marking of acoustic and semantic distractors.

A test of verbal recognition, yielding separate scores for semantic and acoustic distractor errors as well as a simple recognition score, successfully discriminated between various groups of brain-damaged, depressive, and normal subjects in a sequence predictable from their pathology. However, the profile of distractor errors was similar for all groups tested, with a consistent tendency for subjects to make more semantic errors than acoustic errors in all cases. It was concluded that the failure to find qualitative coding differences was probably a consequence of the procedure used and did not necessarily contradict previous findings that amnesics were less effective than normal subjects in coding semantically.