Effects of tDCS applied over the left IFG and pSTG language areas on verb recognition task performance

Abstract

Knowledge about the relevance of the left inferior frontal gyrus (lIFG) and the left posterior superior temporal gyrus (lpSTG) in visual recognition of word categories is limited at present. tDCS is a non-invasive brain stimulation method that alters cortical activity and excitability, and thus might be a useful tool for delineating the specific impact of both areas on word recognition. The objective of this study was to explore whether the visual recognition process of verb categories is improved by a single tDCS session. lIFG and lpSTG areas were separately modulated by anodal tDCS to evaluate its effects on verbal recognition. Compared to sham stimulation, motor reaction times (RTs) were reduced after anodal tDCS over the lpSTG, and this effect was independent of the performing hand (right/left). These findings suggest that this region is involved in visual word recognition independently from the performing hand.