Transcranial Direct Current Stimulation Over the Right Frontal Inferior Cortex Decreases Neural Activity Needed to Achieve Inhibition: A Double-Blind ERP Study in a Male Population

Abstract

Inhibitory control refers to the ability to inhibit an action once it has been initiated. Impaired inhibitory control plays a key role in triggering relapse in some pathological states, such as addictions. Therefore, a major challenge of current research is to establish new methods to strengthen inhibitory control in these "high-risk" populations. In this attempt, the right inferior frontal cortex (rIFC), a neural correlate crucial for inhibitory control, was modulated using transcranial direct current stimulation (tDCS). Healthy participants (n = 31) were presented with a "Go/No-go" task, a well-known paradigm to measure inhibitory control. During this task, an event-related potential (ERP) recording (T1; 32 channels) was performed. One subgroup (n = 15) was randomly assigned to a condition with tDCS (anodal electrode was placed on the rIFC and the cathodal on the neck); and the other group (n = 16) to a condition with sham (placebo) tDCS. After one 20- minute neuromodulation session, all participants were confronted again with the same ERP Go/No-go task (T2). To ensure that potential tDCS effects were specific to inhibition, ERPs to a face-detection task were also recorded at T1 and T2 in both subgroups. The rate of commission errors on the Go/No-go task was similar between T1 and T2 in both neuromodulation groups. However, the amplitude of the P3d component, indexing the inhibition function per se, was reduced at T2 as compared with T1. This effect was specific for participants in the tDCS (and not sham) condition for correctly inhibited trials. No difference in the P3 component was observable between both subgroups at T1 and T2 for the face detection task. Overall, the present data indicate that boosting the rIFC specifically enhances inhibitory skills by decreasing the neural activity needed to correctly inhibit a response.

Without Blinking an Eye: Proactive Motor Control Enhancement

“…Previous studies have found that anodal stimulation of the rIFG resulted in a shorter SSRT, an index of efficient response inhibition (Campanella et al 2017;Jacobson et al 2011;Jacobson et al 2012a, b;Stramaccia et al 2015). The current study did not replicate this finding.…”

Just Swap Out of Negative Vibes? Rumination and Inhibition Deficits in Major Depressive Disorder: Data from Event-Related Potentials Studies

“…An interesting question would be whether boosting inhibition in MDD patients could lead to less rumination. For instance, cognitive training ( Ditye et al, 2012 ) and neuromodulation techniques, such as repetitive Transcranial Magnetic Stimulation (rTMS) or transcranial Direct Current Stimulation (tDCS) ( Hsu et al, 2011 ; Ditye et al, 2012 ; Juan and Muggleton, 2012 ; Campanella et al, 2016 ), have already been used to boost inhibitory functioning in normal controls and other psychopathological states. Indeed, cognitive training is an effective tool to improve a variety of cognitive functions.…”

“…Indeed, cognitive training is an effective tool to improve a variety of cognitive functions. Regarding tDCS, it has previously been demonstrated that stimulation over the right inferior frontal gyrus (rIFG) facilitates behavioral inhibition performance and modulates its neurophysiological correlates ( Campanella et al, 2016 ). Recently, researchers have begun to combine cognitive training and brain stimulation in order to assess the enhancing/synergic effect of those techniques.…”

Addiction: Brain and Cognitive Stimulation for Better Cognitive Control and Far Beyond

“…In another study, tDCS over the pre SMA during a stop-signal task increases activity in the pre SMA after anodal stimulation during stop trials and was associated with improved inhibitory control [171]. Finally, after applying tDCS over the rIFG, two studies [170,172] observed a decrease in P3 amplitude during no-go and/or stop trials in anodal compared to inactive stimulation. The clinical value of those results in the case of addictive behaviors remains to be seen.…”