Table 1:
Studies about tDCS of the DLPFC for addictive disorders.
| Studies | n | Participants | Design | Number of sessions | Stimulation site | Polarity | Current (mA) | Effects | Side effects | Location |
|---|---|---|---|---|---|---|---|---|---|---|
| DLPFC as the stimulation site | ||||||||||
| Fregi et al. (2008) | 24 | Smokers: >15 cigarettes per day; 1.5 h abstinence |
Randomized, double-blinded, sham-controlled, crossover study | 3 (1 anodal left; 1 anodal right; 1 sham) | Left and right DLPFC | A/C/S | 2 | Reduction of cue-induced craving after both active tDCS conditions; no effect on mood changes | Scalp burning, headache, itching, no difference between groups | 10–20 EEG system |
| Xu et al. (2013) | 24 | Smokers: >15 cigarettes per day; 1.5 h abstinence |
Single-blind, sham-controlled study | 2 (1 Ac and 1 S) | Left DLPFC | A/S | 2 | No effect on cue-induced nicotine smoking following active tDCS; no effect on attention; mood improvement | Tingling, scalp burning, sleepiness | 10–20 EEG system |
| Boggio et al. (2009) | 27 | Smokers: > 10 cigarettes per day; 1.5 h abstinence | Randomized, double-blinded, sham-controlled, crossover study | 5 | Left DLPFC | A/S | 2 | Reduction of cue-provoked craving and cigarette consumption | Scalp burning, headache, itching; no difference between groups | 10–20 EEG system |
| Fecteau et al. (2014) | 12 | Light, moderate and heavy smokers | Randomized, double-blind, sham-controlled study | 5 | Left and right DLPFC | A/C/S | 2 | Reduction in number of cigarettes smokers lasting up to 4 days following active stimulation. No effect on risk task. Effect on Ultimatum task, rejection of cigarettes as an offer | Sleepiness, headache, pain | 10–20 EEG system |
| Nakamura-Palacios et al. (2012) | 49 | Alcohol-dependent: detoxified; treatment-seekers; 7 days abstinence | Randomized, single-blind, sham-controlled study | 2 (1 Ac and 1 S) while participants were exposed to visual cues | Left DLPFC | A/S | 1 | No effect on frontal activity as indexed by P3 in response to auditory alcohol related stimuli, except that in Lesch IV alcoholics showing increasing P3 amplitude after real tDCS | Itching and tingling reported for both sham and real stimulation | 10–20 EEG system |
| Boggio et al. (2008) | 13 | Alcohol-dependent: detoxified; treatment seekers; >10 days abstinence | Randomized, double-blind, sham-controlled, cross-over study | 3 (1 anodal left/cathodal right; 1 anodal right/cathodal left; 1 sham) | Left and right DLPFC | A/C/S | 2 | Reduction of craving by both active tDCS conditions | Discomfort, headache | 10–20 EEG system |
| da Silva et al. (2013) | 13 | Alcohol-dependent: detoxified; in treatment; >10 days abstinence; in routine clinical treatment | Randomized, single-blind, sham-controlled study | 5 (1/week) | Left DLPFC | A/S | 2 | No effects of real stimulation on relapse rate; reduction in craving for alcohol and in POMS depression score | NS | 10–20 EEG system |
| den Uyl et al. (2015) | 41 | Heavy drinkers | Randomized, double-blind, sham-controlled study | 3 (1 DLPFC; 1 IFG; 1 sham) | Left DLPF and IFG | A/S | 1 | Reduction of inclination toward drinking by real DLPFC stimulation. No effect of IFG stimulation. No effect of real stimulation on alcohol-related attentional biases | None | 10–20 EEG system |
| Conti et al. (2014) | 13 | Crack-cocaine: average of 30 days of abstinence | Randomized, single-blind, sham-controlled study | 5 | Left and right DLPFC | A/C/S | 2 | Inhibitory effect on P3 drug-cued cortical activation by a single dose of active tDCS; increase after 5 sessions | Itching and tingling reported for both sham and real tDCS | 10–20 EEG system |
| Gaudreault et al. (2021) | 17 | Cocaine inpatients | Randomized double-blind sham-controlled | 2 (1 right anodal/left cathodal; 1 sham) | Left and right DLPFC | A/C/S | 2 | Reduction in craving induced by real stimulation | Tingling, burning, itching, and the experience of fatigue | 10–20 EEG system |
| Shahbabaie et al. (2014) | 32 | Methamphetamine-dependent; abstinent | Randomized, double-blind, crossover sham-controlled study | 2 (1 Ac and 1 S) at rest and during cue-inducing task | Right DLPFC | A/S | 2 | Reduction in spontaneous craving after 10 min stimulation induced by real stimulation; increase in cue-induced craving by real stimulation | Drowsiness, tingling, itching | 10–20 EEG system |
| Shahbabaie et al. (2018) | 15 | Methamphetamine-dependent | Double-blind, sham-controlled crossover study | 2 (1 anodal right/cathodal left; 1 sham) | Left and right DLPFC | A/S | 2 | Reduction in craving induced by real stimulation | NS | 10–20 EEG system |
| Xu et al. (2021) | 75 | Methamphetamine-dependent; abstinent | Randomized, single-blind, sham controlled study | 3 (1 CCAT + anodal right/cathodal left; 1 CCAT + sham;1 control) | Left and right DLPFC | A/C/S | 1.5 | Reduction in cue-induced craving and improvement in accuracy of two back tasks of real stimulation | Tingling and itching | 10–20 EEG system |
| Other stimulation sites | ||||||||||
| Wang et al. (2016) | 20 | Heroin-dependent; in treatment; 1.5–2 years abstinence | Randomized, single-blind, sham controlled study | 2 (1 Ac and 1 S) | FPT | C/S | 1.5 | Significant difference between pre- and poststimulation cue-induced craving score following real stimulation | None | 10–20 EEG system |
| Meng et al. (2014) | 30 | Smokers: >8 cigarettes per day | Randomized, double-blind, sham-controlled study | 3 (2 Ac and 1 S) | FPT | C/S | 1 | Bilateral cathodal stimulation of the FPT areas significantly reduced the attention to smoking-related cues and daily cigarette consumption on the following day | Tingling, itching, pain | 10–20 EEG system |
A = anodal; Ac = active; C = cathodal; FPT = fronto-parietal-temporal areas; IFG = inferior frontal gyrus; NS = not specified; POMS = Profile of Mood States; S = sham.