AUTHOR=Cellini Nicola , Shimizu Renee E. , Connolly Patrick M. , Armstrong Diana M. , Hernandez Lexus T. , Polakiewicz Anthony G. , Estrada Rolando , Aguilar-Simon Mario , Weisend Michael P. , Mednick Sara C. , Simons Stephen B. 

TITLE=Short Duration Repetitive Transcranial Electrical Stimulation During Sleep Enhances Declarative Memory of Facts

JOURNAL=Frontiers in Human Neuroscience

VOLUME=13

YEAR=2019

URL=https://www.frontiersin.org/journals/human-neuroscience/articles/10.3389/fnhum.2019.00123

DOI=10.3389/fnhum.2019.00123

ISSN=1662-5161

ABSTRACT=<p>Transcranial electrical stimulation (tES) during sleep has been shown to successfully modulate memory consolidation. Here, we tested the effect of short duration repetitive tES (SDR-tES) during a daytime nap on the consolidation of declarative memory of facts in healthy individuals. We use a previously described approach to deliver the stimulation at regular intervals during non-rapid eye movement (NREM) sleep, specifically stage NREM2 and NREM3. Similar to previous studies using tES, we find enhanced memory performance compared to sham both after sleep and 48 h later. We also observed an increase in the proportion of time spent in NREM3 sleep and SDR-tES boosted the overall rate of slow oscillations (SOs) during NREM2/NREM3 sleep. Retrospective investigation of brain activity immediately preceding stimulation suggests that increases in the SO rate are more likely when stimulation is delivered during quiescent and asynchronous periods of activity in contrast to other closed-loop approaches which target phasic stimulation during ongoing SOs.</p>