Stress effects on declarative memory retrieval are blocked by a beta-adrenoceptor antagonist in humans

Previous evidence indicates that stress hormone effects on memory consolidation depend on concurrent emotional arousal-induced noradrenergic activity. Here, we asked whether this is also true for stress effects on memory retrieval and hypothesized that administration of the beta-adrenoceptor antagonist propranolol would block the effects of stress on declarative and procedural retrieval performance. In a double-blind, placebo-controlled, crossover study, 44 healthy young men learned a list of emotional and neutral words (declarative memory task) and completed a serial reaction time task (procedural memory task). On the following day, participants received either a placebo or 40 mg propranolol orally. One hour later, they were exposed to stress (socially evaluated cold pressor test (SECPT)) or a control condition 30 min prior to retention testing. Stress selectively enhanced the retrieval of emotionally arousing words. Pretreatment with propranolol had no effect on memory alone but blocked the stress-induced memory enhancement for emotional words, confirming the importance of noradrenergic activity in stress effects on memory retrieval. Memory for neutral words and the procedural task was neither affected by stress nor by propranolol. The present findings suggest that stress (hormone) effects on emotional memory retrieval require concurrent noradrenergic activation. Procedural memory retrieval and the retrieval of neutral verbal material appear to be less susceptible to stress.