Pharmacological models of memory dysfunction? A comparison of the effects of scopolamine and lorazepam on word valence ratings, priming and recall.

The effects of scopolamine (0.3, 0.6 mg IM) lorazepam (2 mg oral) and placebo on word valence ratings, priming and word recall were assessed in a double-blind independent group design with 36 subjects. Subjects given active drugs rated words as having more of an affective load than subjects given placebo. Priming, as assessed in a word-stem completion task, was not significantly affected by any treatment. Word recall showed some impairment following all active treatments. Performance on the stem completion task was unrelated to subjectively rated sedation but did not relate to word-valence ratings in different ways across drug treatments. Performance on the recall task was unrelated to valence ratings but did relate to the sedative effects on lorazepam. Implications are drawn out for pharmacological models of memory dysfunction.