A Discussion of tACS Literature
The effects of transcranial alternating current stimulation (tACS) at individual alpha peak frequency (iAPF) on motor cortex excitability in young and elderly adults.
Fresnoza, Shane, Monica Christova, Theresa Feil, Eugen Gallasch, Christof Körner, Ulrike Zimmer, & Anja Ischebeck. 2018. The effects of transcranial alternating current stimulation (tACS) at individual alpha peak frequency (iAPF) on motor cortex excitability in young and elderly adults. Experimental Brain Research. 236: 2573-88.
Summary: In this study experimenters collected a variety of cortical excitability measures using a combination of TMS and tACS presented at individualized alpha frequencies compared to sham. The researchers compared participants in two age groups (18-28 & 56-67 years old) to determine if the alpha-tACS changed later in adulthood where alpha is shown to reduce in power and frequency. MEP amplitudes increased for both older and younger adults, but SICI was found to show differential patterns between the groups. SICI shifted to facilitation in the younger group 60 minutes after alpha-TACS, whereas the older group started out showing facilitation effects at SICI latencies, then shifting to the more traditionally seen inhibition at 60 minutes. These findings highlight the potential for using tACS in older populations to normalize cortical activity patterns that
Contributed by: Christopher Walker, PhD
Every week, there are new and exciting scientific papers published on studies that investigated tACS. Reading and understanding these papers unfortunately requires both access to (sometimes quite expensive) scientific journals and in-depth "insider knowledge." Our goal is to share with you brief summaries of tACS studies that give you a big-picture idea of what the publications are about. There are too many studies to feature all of them but we will continuously update this page. If you have a specific study you would like to get featured, please contact us. The contributors are personnel from the Frohlich Lab and the Carolina Center for Neurostimulation.