The effects of single-dose lorazepam on memory and behavioural learning.
To assess the influence of lorazepam on memory and behavioural learning, a non-clinical sample of undergraduate psychology students (n = 24), received lorazepam (2.5 mg) or placebo orally. Pre-drug and post-drug neuropsychological assessment comprised the Rey auditory verbal learning test, verbal fluency test, digit span and word stem completion. Relative to placebo, lorazepam induced a marked deficit in delayed free-recall, perceptual priming, and written word fluency, with preservation of digit span. Behavioural learning was assessed on a computer-aided vicarious exposure treatment for obsessive-compulsive disorder, administered post-drug, and repeated 1 week later, drug free. Compared to placebo, lorazepam treated participants enacted 51% less exposure activity on the behavioural learning task post-drug. Whilst both groups enacted increased exposure at the drug-free session, exposure activity was 49% less in the lorazepam group, indicating a carryover effect of the impaired learning under drug 1 week before. There were no significant differences between lorazepam and placebo on indices of overall activity on the program. These results suggest lorazepam-induced impairment in the ability to learn behavioural strategies, possibly due to impaired acquisition of information into long-term episodic memory. These findings suggest caution in the co-prescribing of benzodiazepines in people undergoing behavioural therapies in clinical populations.
Matthews
Allison
A
School of Psychology, University of Tasmania, Hobart, Australia. allison.matthews@utas.edu.au
Kirkby
Kenneth C
KC
Martin
Frances
F
D000293:Adolescent; D000328:Adult; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D005260:Female; D006235:Hand Disinfection; D006801:Humans; D007858:Learning / Q000187:drug effects*; D008140:Lorazepam / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D008570:Memory, Short-Term / Q000187:drug effects; D009483:Neuropsychological Tests; D009771:Obsessive-Compulsive Disorder / Q000523:psychology
D014151:Anti-Anxiety Agents; D008140:Lorazepam