Reactivating specific memories during sleep in conjunction with a suppression context

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Gayathri Subramanian¹ (gayathrisubramanian2024@u.northwestern.edu), Christina Zelano¹, Ken A Paller¹, Eitan Schechtman²; ¹Northwestern University, ²University of California, Irvine

Recently acquired memories are reactivated during sleep, leading to their strengthening. Reactivation can be biased using odor and sound presentations during sleep to benefit associated memories (targeted memory reactivation). For example, when a rose odor served as context during object-location learning and was later presented during sleep, location recall improved. Likewise, sounds linked with individual objects and unobtrusively presented during sleep also improved recall. We hypothesized that joint reactivation of odors and sounds may create synergistic effects. In addition, we hypothesized that odors could enhance memory suppression. Participants first engaged in an odor-based directed-forgetting task, whereby one odor was linked with instructions to remember and another with instructions to forget. A third odor was not used and functioned as a control. During a nap, each of the three odors were presented concurrently with sounds previously linked with object-location learning. Spatial recall was tested after sleep. Objects reactivated with the control odor showed memory-strength-dependent improvement, as in previous targeted-memory-reactivation studies. Contrary to prediction, concurrent presentation of remember or forget odors with object sounds did not clearly impact spatial recall. Furthermore, sleep spindles were more frequent following control-odor presentation than for the other two odors, suggesting that reactivation of spatial memories was only effective in the control condition. Overall, results parallel prior findings showing that two sound cues presented in rapid succession during sleep block consolidation. We posit that conjoint presentation of a sound with a meaningful odor nullifies the benefits of reactivation.

Topic Area: LONG-TERM MEMORY: Episodic