TMS studies of working memory enhancement and deep brain stimulation

Authors

• B Luber
• Z-D Deng
• A Peterchev
• S Davis
• D Murphy
• SH Lisanby

Abstract

We present two studies employing novel uses of TMS. In the first, cognitive paired-associate stimulation (CPAS) is introduced. Healthy adult volunteers undergo two days of total sleep deprivation in order to produce a temporary deficit in working memory (WM) performance. 5Hz TMS is applied to lateral occipital complex while subjects simultaneously perform a WM task in four sessions over the course of sleep deprivation. This repeated use of simultaneous TMS and WM training resulted in almost complete remediation of deprivation-induced WM deficits, a full 18hrs after the last TMS session. This CPAS methodology may have applications in defending functional circuitry in the brain against deterioration found in other settings, such as aging. In the second study, a method to target deep brain structures using TMS is demonstrated. Using diffusion tensor imaging (DTI), white matter tracts were traced from a seed area in BA25 (a region far to deep to reach directly with TMS) to frontal pole cortex, which is easily targeted by TMS. Using concurrent single pulse TMS and fMRI, we show that BA25 is activated in a dose-dependent way with this stimulation. This represents an initial step towards using tractography-guided TMS to noninvasively target areas for therapy and for research no matter where they are situated in the brain.

Scientific Focus Area: Neuroscience

This page was last updated on Friday, March 26, 2021