Abstract
OBJECTIVE: This study investigated the effects of repeated transcranial direct current stimulation on response inhibition and sought to elucidate the underlying neurobehavioral mechanisms. METHODS: In a randomized, triple-blind, sham-controlled, 36 male soccer players were assigned to active-tDCS, sham-tDCS, or no-intervention control groups. The active-tDCS group received 20-min 1.5 mA tDCS over the right dorsolateral prefrontal cortex (DLPFC) five times weekly for 4 weeks, alongside regular training. The sham-tDCS group received 1-min 1.5 mA tDCS with regular training, and the no-intervention control group only regular trained. Pre- and post-intervention, all participants performed a Go/No-go task while behavioral and event-related potential (ERP) data were recorded. Behavioral metrics: Go reaction time (RT), Go accuracy (ACC), and No-go accuracy. ERP metrics: P3 amplitude and latency. RESULTS: Behavioral: Only the active-tDCS group showed significantly shorter Go RT post-intervention compared to baseline and the control group. The ACC for the three groups of Go and No-go tasks remained unchanged. ERP: Only the active-tDCS group exhibited increased P3 amplitude and reduced P3 latency during both Go and No-go trials. A significant three-way interaction indicated that latency shortening in No-go trials was most pronounced at central sites Cz/Cpz. The sham-tDCS group and the no-intervention control group showed no significant changes in P3 amplitude and latency between pre-tests and post-tests. DISCUSSION: These preliminary findings suggest that repeated tDCS over the right prefrontal cortex may enhance behavioral response speed in soccer players, accompanied by neurophysiological changes indicative of optimized processing efficiency (increased P3 amplitude and shortened latency). However, given the exploratory nature and modest sample size, these results warrant confirmation in larger-scale studies. CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/showproj.html?proj=288285, ChiCTR2500109387.