Objective: Elevated glucocorticoid levels impair retrieval of emotional information, and animal studies indicate that this effect depends on concurrent emotional arousal-induced increases in noradrenergic transmission within the brain. The authors investigated whether the beta-adrenoceptor antagonist propranolol blocks glucocorticoid-induced memory retrieval impairments in human subjects.
Method: In a double-blind, placebo-controlled study, 42 healthy volunteers were presented a set of words with variable emotionality and asked to learn them for recall. A day later, cortisone (25 mg), propranolol (40 mg), or both drugs were administered orally 1 hour before a free-recall test.
Results: Cortisone selectively impaired the recall of emotionally arousing words by 42%. This impairment was blocked by the concurrent administration of propranolol. Propranolol alone did not affect recall of either emotional or neutral words.
Conclusions: A pharmacological blockade of beta-adrenoceptors prevents glucocorticoid-induced memory retrieval deficits in human subjects. This finding may have important implications for the treatment of memory deficits in hypercortisolemic states, such as stress and depression.