Activation of Inhibition: Diminishing Impulsive Behavior by Direct Current Stimulation over the Inferior Frontal Gyrus

摘要

A common feature of human existence is the ability to reversendecisions after they are made but before they are implemented.nThis cognitive control process, termed response inhibition, refersnto the ability to inhibit an action once initiated and has been localizednto the right inferior frontal gyrus (rIFG) based on functionalnimaging and brain lesion studies. Transcranial direct current stimulationn(tDCS) is a brain stimulation technique that can facilitatenas well as impair cortical function. To explore whether responseninhibition can be improved through rIFG electrical stimulation,nwe administered focal tDCS before subjects performed the stopnsignal task (SST), which measures response inhibition. Notably,nactivation of the rIFG by unilateral anodal stimulation significantlynimproved response inhibition, relative to a sham condition,nwhereas the same tDCS protocol did not affect response time innthe go trials of the SST and in a control task. Furthermore, the SSTnwas not affected by tDCS at a control site, the right angular gyrus.nOur results are the first demonstration of response inhibition improvementnwith brain stimulation over rIFG and further confirmnthe rIFG involvement in this task. Although this study was conductednin healthy subjects, present findings with anodal rIFGstimulationnsupport the use of similar paradigms for the treatment ofncognitive control impairments in pathological conditions. ■