Neutral and emotional episodic memory: global impairment after lorazepam or scopolamine.
BACKGROUND
Benzodiazepines and anticholinergic drugs have repeatedly been shown to impair episodic memory for emotionally neutral material in humans. However, their effect on memory for emotionally laden stimuli has been relatively neglected.


OBJECTIVE
We sought to investigate the effects of the benzodiazepine, lorazepam, and the anticholinergic, scopolamine, on incidental episodic memory for neutral and emotional components of a narrative memory task in humans.


METHODS
A double-blind, placebo-controlled independent group design was used with 48 healthy volunteers to examine the effects of these drugs on emotional and neutral episodic memory.


RESULTS
As expected, the emotional memory advantage was retained for recall and recognition memory under placebo conditions. However, lorazepam and scopolamine produced anterograde recognition memory impairments on both the neutral and emotional components of the narrative, although floor effects were obtained for recall memory. Furthermore, compared with placebo, recognition memory for both central (gist) and peripheral (detail) aspects of neutral and emotional elements of the narrative was poorer after either drug.


CONCLUSIONS
Benzodiazepine-induced GABAergic enhancement or scopolamine-induced cholinergic hypofunction results in a loss of the enhancing effect of emotional arousal on memory. Furthermore, lorazepam- and scopolamine-induced memory impairment for both gist (which is amygdala dependent) and detail raises the possibility that their effects on emotional memory do not depend only on the amygdala. We discuss the results with reference to potential clinical/forensic implications of processing emotional memories under conditions of globally impaired episodic memory.
Kamboj
Sunjeev K
SK
Clinical Psychopharmacology Unit, Sub-department of Clinical Health Psychology, University College London, London, WC1E 6BT, UK. sunjeev.kamboj@ucl.ac.uk
Curran
H Valerie
HV
D000293:Adolescent; D000328:Adult; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D004311:Double-Blind Method; D004644:Emotions / Q000187:drug effects; D005260:Female; D018757:GABA Modulators / Q000494:pharmacology; D006801:Humans; D008140:Lorazepam / Q000494:pharmacology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D018727:Muscarinic Antagonists / Q000494:pharmacology*; D012601:Scopolamine / Q000494:pharmacology*
D014151:Anti-Anxiety Agents; D018757:GABA Modulators; D018727:Muscarinic Antagonists; D012601:Scopolamine; D008140:Lorazepam