DNA Methylation: A Potential Mediator of the Memory Regulatory Effects of taVNS.

Transcutaneous auricular vagus nerve stimulation (taVNS), an emerging noninvasive neuromodulation technique, has shown promise for improving memory. A better understanding of the epigenetic mechanisms underlying the effects of taVNS would inform the molecular outcomes essential for memory and cognition. In this review, we synthesize the current literature on the neurophysiological and biochemical basis of taVNS. Next, we explore how DNA methylation regulators (e.g., DNA methyltransferase 3a) and readers (e.g., methyl-CpG binding protein 2) differentially regulate memory, and how their activity and expression can be regulated by neuronal activity. Finally, we describe the potential involvement of DNA methylation in mediating the memory regulatory effects of taVNS and discuss possible directions for future studies.