Effects of high-definition transcranial direct current stimulation on drug craving in patients with methamphetamine use disorder

Background: High-definition transcranial direct current stimulation (HD-tDCS) has been used as a non-invasive brain stimulation technique in drug-addicted populations. The current study found that HD-tDCS may reduce drug craving in methamphetamine (MA) addicts by stimulating the left and right sides of the dorsolateral prefrontal cortex (DLPFC) in the brain. Methods: In this study, 60 patients with MA use disorder were recruited and randomly assigned to three groups: the left DLPFC group, the right DLPFC group, and the sham stimulation group, the groups received a 20-min HDtDCS intervention for 8 consecutive days. The stimulation intensity was set at 1.5 mA, but in the sham stimulation group, the current increased to 1.5 mA within 30 s of the start of the intervention, and then rapidly decreased to 0 to cause the stimulation sensation. All groups completed tests related to physiological, explicit and implicit drug craving during the pre and post-testing phases, and were followed up after 1 month. Results: (a) compared with the pre-test data, the left and right DLPFC groups at the post-test stage showed significant decreases in heart rate values, explicit and implicit drug craving scores, while the sham stimulation group showed no significant differences; (b) the intervention effects on drug craving scores were compared between the left and right DLPFC groups found no significant differences; (c) one-month follow-up test found that compared with the pre-test, the left and right DLPFC groups follow-up test explicit craving scores were significantly lower compared to the pre-test, but significantly higher compared to the post-test; also implicit drug craving scores were not significantly different compared to the pre-test, but increased compared to the post-test. Conclusion: These results suggest that eight consecutive sessions of HD-tDCS may be effective in reducing immediate drug craving in patients with MA use disorder, but whether the effects of the intervention are sustained needs to be confirmed by further research.