Can Prefrontal tDCS Improve Memory in Younger or Older Adults? A Rigorous Clinical Trial with Null Results

Poster Session E - Monday, April 15, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Tesnim Arar¹, Gabriella V. Hirsch¹, Taylor A. Chamberlain², Cheyenne D. Wakeland-Hart², Miranda Malone¹, Diane S. Lauderdale¹, L. Philip Schumm¹, David A. Gallo¹; ¹University of Chicago, ²Columbia University

Previous work has found that a single session of anodal tDCS to the left dorsolateral prefrontal cortex (dlPFC) can temporarily improve memory in younger or older adults, but this effect has not always been replicated and may be moderated by time of day (see Wong et al., 2018). Here, we report the results from a randomized, controlled trial designed to replicate these time-of-day findings in episodic memory in younger adults, and also to determine the extent these tDCS on working memory and among older adults. We conducted the largest double-blind, between-subjects, multi-session tDCS study on memory to date. One-hundred and fifty younger adults and 91 older adults received anodal tDCS or sham stimulation to the left dlPFC or left parietal cortex prior to episodic memory retrieval and working memory tasks at different times of day (i.e., morning and afternoon). We found expected effects of task difficulty manipulations on each of our memory measures. However, contrary to our primary pre-registered hypotheses, we did not find any effect of tDCS or time of day on younger or older adults’ episodic or working memory performance. Based on these and prior results, we conclude that a single session of tDCS using the typical (and often recommended) parameters does not improve episodic memory retrieval or working memory in either age group.

Topic Area: METHODS: Other