Acute administration of citalopram facilitates memory consolidation in healthy volunteers.

OBJECTIVES: Decreasing serotonergic neurotransmission in humans has been found to impair memory consolidation. Such effects may be relevant to the memory deficits seen in major depression and the cognitive actions of antidepressant drugs used to treat them. However, the improvement in cognitive function often found following successful pharmacological treatment in depression may be confounded by symptom improvement. RATIONALE: The present study assessed the effects of an acute challenge with the selective serotonergic re-uptake inhibitor citalopram in healthy (non-depressed) females. METHODS: Immediate and delayed recall/recognition was assessed using the auditory verbal learning test following 10 mg (intravenous) citalopram or placebo in a double-blind between groups design. RESULTS: Immediate recall on the verbal memory test was unaffected by citalopram administration. However, volunteers receiving citalopram showed enhanced long-term memory performance in terms of delayed recall and recognition relative to those receiving placebo. Sustained attention performance was also comparable in the two groups of subjects suggesting that non-specific increases in information processing are not responsible for this effect. CONCLUSIONS: These results indicate that augmentation of serotonergic neurotransmission is associated with increased memory consolidation, which may be relevant to its therapeutic and cognitive actions in acutely depressed patients.