Date of Award
Master of Arts
Stress has been found to both facilitate and impair memory depending on the memory phase during which the stressor occurs. Generally, stress has been shown to facilitate memory consolidation and impair retrieval. Research has revealed conflicting findings regarding the effect of stress on encoding. While some studies have demonstrated an impairing effect, others have found a facilitatory effect of stress on memory performance. To explain these findings, researchers have suggested a time-dependent effect of stress on memory. Stress is proposed to facilitate memory for temporally proximate events and impair memory for events occurring after a delay. The current study sought to test this hypothesis. Participants were exposed to a cold pressor stress manipulation then randomly assigned to a delay interval between 0 and 60 minutes long. After the delay, participants learned a series of positive, negative and neutral word pairs, and were given a 24 hour delayed cued recall test. Results demonstrated that a cubic regression model was able to significantly predict memory performance based on delay. However, the results differed depending on the sex of the participants. While female participants displayed the expected increased performance at short delays and decreased performance at 15 to 40 minute delay intervals, male participants displayed increased performance at 20 to 35 minute delay intervals. As discussed, a potential explanation for these findings is that the magnitude, direction and time course of the effect of stress on memory may depend on the perceived severity of the stressor and the extent to which participants experience increase activity in the sympathetic-adrenal-medullary axis, hypothalamic-pituitary-adrenal axis or both.
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