OBJECTIVES: Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation method that uses electrodes placed on the scalp to modulate the activity of specific cortical structures in the brain. This technique has wide applications in neurology, psychiatry, and psychology. Research findings suggest that tDCS can influence the expression of psychological traits, such as impulsivity, by stimulating brain structures involved in impulse control, such as the prefrontal cortex (PFC). The study investigated whether tDCS can reduce impulsivity levels in healthy individuals from the general population.

METHODS: The study group consisted of 61 volunteers aged 18-28 years, without diagnosed neurological or psychiatric disorders. Participants were randomly assigned to the active stimulation group (n=29) and the sham stimulation group (n=32). Before the stimulation cycle, participants completed the Polish version of the Barratt Impulsiveness Scale-Brief (BIS-Brief) whose scales assess two components of impulsivity: self-control and impulsivity in action. Stimulation was conducted for five consecutive days, 20 minutes per day for the Real group. The anodal electrode was placed over the F3 area (10-20 system), and the cathodal electrode was placed contralaterally over the F4 area. During the real and sham neuromodulation sessions, short videos were shown to promote healthy behaviors e.g., physical activity, healthy food choices, proper sleeping habits etc., needed to complete another part of the study. Participants completed a post-test 10 to 14 days after the stimulation cycle ended.

RESULTS: The results of the one-tailed independent samples t-test indicated that the change score (post-test minus pre-test) showed a significant reduction in impulsivity in action subscale, but not in self-control in the real stimulation group compared to the sham group.

CONCLUSIONS: These findings suggest that even a relatively short course of neuromodulation with tDCS may prove an effective method of reducing impulsivity. tDCS may thus have the potential to alleviate symptoms of disorders related to impulsive behaviour.