Combined Bifrontal Transcranial Direct Current Stimulation and Auditory Stroop Training in Chronic Tinnitus

Patients with tinnitus experience difficulties in cognitive control and executive functions. Many of which are regarded as the cause of tinnitus rather than its complications. Methods for the improvement of inhibitory and cognitive control seem to be effective in the control of tinnitus. In this study, transcranial direct current stimulation and auditory Stroop exercise were have been to improve inhibitory control and the ability to ignore tinnitus in patients suffering from chronic tinnitus. 34 patients with chronic tinnitus (> 6 months) were randomly divided into two groups. The first group consist of 17 patients who received 6 sessions of tDCS followed by 6 sessions of auditory Stroop training. The second group received 6 sessions of sham tDCS followed by 6 sessions of auditory Stroop training. The initial evaluations including pure tone audiometry, psychoacoustic measurements, tinnitus handicap inventory (THI) survey and visual analog scale (VAS) of annoyance and loudness were performed before, immediately after, and one month after the tDCS, sham, and Stroop training. The results of this study revealed a significant reduction in THI score, VAS of loudness, and annoyance of tinnitus. A significant correlation was detected between the reaction time of incongruent words in the Stroop task and improvement of THI score and VAS of annoyance. Combined tDCS and Stroop training efficiently improve chronic tinnitus.