Memory Reconsolidation Memory is subject to change.

1. The Effects of Stress on Memory Reconsolidation of Emotional StimuliJoelle Dorskind, Advisor: Dr. Almut Hupbach Lehigh University Psychology Department Reconsolidation • Goal of this study • To determine the effects of stress on memory reconsolidation, specifically looking at the effects of emotional memory reconsolidation. • I hypothesized that stress would modulate (enhance or impair) memories, especially emotional ones, when stress is administered after memory reactivation. Design Stable Memory Reactivation Plastic Memory • Discussion • Contrary to the hypothesis, there was no difference between the cold pressor and warm water control groups in memory performance for both the negative and neutral images. • There was also no difference in performance for non-reactivated items. • There was a significant difference among the reactivated images when comparing negative and neutral pictures (not modulated by the cold pressor). • Participants recognized more negative compared to neutral images, and were less likely to reject neutral pictures. • Increasing the number of reactivated items did not change the results. • Stress and Reconsolidation • Andreano & Cahill (2006) have shown that stress can effectively modulate the long-term initial storage of memories (i.e., consolidation). • High levels of stress hormones interfere with memory storage. • Glucocorticoid-induced memory enhancement is known to depend on beta-adrenoceptor activation in the basolateral amygdala (McGaugh, 2000). • This is due to the presence of many corticosteroid receptors in the hippocampus, which are key in the formation of new memories. • Will stress exert the same memory modifying effect when it occurs right after memory retrieval? • Important implications for anxiety disorders associated with traumatic memories, such as post-traumatic stress disorder (PTSD). • References • Andreano, J.M. and Cahill, L. Glucocorticoid Release and Memory Consolidation in Men and Women. Psychological Science 17:466-70 (2006). • Hupbach, A., Gomez, R., & Hardt, O. (2007). Reconsolidation of episodic memories: A subtle reminder triggers integration of new information. Learning Memory, 14, 47-53. • Hupbach, A., Gomez, R., & Nadel, L. (2009). Episodic memory reconsolidation: Updating or source confusion?. Memory, 17(5), 502-510. • McGaugh, J. L. (2000). Memory-a century of consolidation. Science, 287, 248-251. • Nader, K., Schafe, G. E., & Le Doux, J. E. (2000). Fear memories require protein synthesis in the amygdala for reconsolidation after retrieval. Nature, 406(17), 722-726. Memory Reconsolidation • Memory is subject to change. • Nader et al. (2000) hypothesized that reactivation of a stored memory puts that memory into a fragile state. • A reactivated memory needs to be reconsolidated (“re-stored”) in order be retained, or else, it might be lost. • Reconsolidation has been extensively studied in animals, and only recently have researchers begun to look at reconsolidation in human memory. • Hupbach et al. (2007, 2009) have successfully demonstrated reconsolidation effects in humans.