Table 1.
Studies | Studied condition | N | Participants inclusion criteria | Mean age (years) | Proportion of females | Main exclusion criteria | Design | Objective | Main experimental conditions | Main outcome measures | Main results | Drop out (reason) |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Fregni et al., 2008b | Food craving | 23 | Healthy subjects aged 18–55. Frequent food craving (>3 times/day) and strong urges to eat |
23.7 | 91.3% | NS | Randomized Sham-controlled Double-blind Crossover design |
Investigate the effect of tDCS on food cue-induced craving-related behavior | Exposition to food and watching a movie of food associated with strong craving | Food craving (VAS) and food consumption before and after treatment Visual attention to food using an eye tracking system |
Craving for viewed foods was reduced by anode right/cathode left tDCS After sham stimulation, exposure to real food or food-related movie increased craving After anode left/cathode right tDCS, the food-related stimuli did not increase craving levels |
2 (School work) |
Goldman et al., 2011 | Food craving | 19 | Healthy subjects aged 21–70 with frequent food cravings (≥3 times/week during the past month) BMI < 40 |
32.4 | 68.4% | Pregnancy History of an ED or depression Suicidality Implanted metal devices History of seizures, brain surgery |
Randomized Sham-controlled Single-blind Within-subject crossover design |
Investigate the effect of tDCS on food cue-induced craving and the ability to resist foods | Twenty-four images of foods (e.g., ice cream, cheese-burgers, pizza) were presented in random | Food craving and ability to resist tasting (VAS) while viewing food image | Food cravings ratings were reduced in both conditions The percent change in self-reported cravings from pre- to post-stimulation was significantly greater for real stimulation Decrease in food craving, particularly for sweets and carbohydrates No change in food consumption |
1 (NS) |
Montenegro et al., 2012 | Hunger, satiety and desire to eat sensations | 9 | Overweight subjects 2–3 h fasting | 24 | 44.4% | Cardiovascular disease Pregnancy, History of eating disorders Depression Implanted metal parts |
Randomized Single-blinded Sham-Controlled Crossover design |
Investigate the effect of tDCS isolated or combined with aerobic exercise on the desire to eat, hunger, and satiety | No exposition to food | Appetite sensations (VAS) evaluated at four moments: baseline; after tDCS; post-exercise; 30 min post-exercise | tDCS on left DLPFC decreased the desire to eat at baseline tDCS associated with exercise had greater suppressing effect in desire to eat compared to either tDCS or exercise alone tDCS associated with exercise decreased hunger and increased satiety immediately after exercise |
0 |
Kekic et al., 2014 | Food craving and temporal discounting | 17 | Healthy women aged 18–60 with frequent food cravings (≥1 per day) | 26.4 | 100% | SUD Major psychiatric disorder Current or past history of an eating disorder Personal or family history of seizures Implanted metal devices Pregnancy |
Randomized Double-blind Sham-controlled Within-subjects crossover design |
Investigate the effect of tDCS on food cravings, intertemporal choice behavior, actual food consumption and temporal discounting | Exposition to real food | VAS measuring baseline hunger FCT FCQ-S Saliva sample TD task |
tDCS reduced cravings for sweet but not savory foods Participants who exhibited more reflective choice behavior were more susceptible to the anticraving effects of tDCS than those who displayed more impulsive choice behavior. | 1 (Skin irritation) |
Khedr et al., 2014 | Urge to restrict food intake | 7 | Treatment-resistant AN BMI between 14 and 17.5 kg/m2 |
21.75 | 85.7% | Drugs (dopaminergic, psychotropic, antiepileptic, or hormonal drugs Estrogen) at least 2 weeks before the study Six patients had been receiving antidepressant (SSRls) which was kept constant throughout the study | Open-label, single-arm study | Evaluate the acceptability of tDCS as a potential treatment for AN Investigate the effect of tDCS on the urge to restrict food intake and symptoms of depression associated with AN. |
No exposition to food | EAT EDI BDI |
Significant effect of time (pre, post, and 1 month later) on the three rating scores Significant correlation between the percent improvement of BDI and EAT and between BDI and EDI Ten daily sessions of anodal tDCS over the left DLPFC improved symptoms of both depression and AN for up to 1 month |
0 |
Lapenta et al., 2014 | Food consumption and ERP-indexed inhibitory control | 9 | Healthy females. Frequent (>3 times/day) and strong urges to eat |
23.4 ± 2 years) | 100% | Neuropsychiatric disorder History of abuse of alcohol or another drug Psychiatric medication Pregnancy Eating disorder |
Randomized Double-blind Sham-controlled Crossover design |
Evaluate the cognitive ERPs that are associated with the effects of DLPFC tDCS on food craving | Exposition to food and watching a movie of food associated with strong craving Go/No-go task that contained pictures of food and furniture (a control visual stimulus). | ERP during a Go/No-Go task Food craving (VAS) while exposed to real food and a movie of food Snack intake; Attentional bias for food (eye tracking) |
Active DLPFC tDCS (anode right/cathode left), compared with sham stimulation, reduced the frontal N2 component and enhanced the P3a component of responses to No-go stimuli, regardless of the stimulus condition (food or furniture). Active tDCS was also associated with a reduction in caloric intake | 0 |
Jauch-Chara et al., 2014 | Food intake | 14 | Healthy young normal-weight men with BMI from 20 to 25. Low cognitive restraint, low disinhibition, and normal susceptibility to hunger scores | 24.8 | 0% | Any medication Acute and chronic medical diseases Alcohol or drug abuse, Smoking Participation in competitive sports Disturbances in sleep continuity |
Randomized Sham-controlled Single-blind Code-based, Counter-balanced Crossover design |
Investigate the effect of repetitive tDCS to the right DLPFC on food intake |
Exposition to food and consomption | Subjective appetite (ratings and VAS) Food intake behavior from a standardized ad libitum buffet |
tDCS reduced food consumption in humans | 0 |
AN, Anorexia Nervosia; BDI, Beck Depression Inventory; BMI (in kg/m2), Body Mass Index; DLPFC, Dorsolateral Prefrontal Cortex; EAT, Eating Attitude Test; EDI, Eating Disorder Inventory; ERPs, event-related potentials; FCQ-S, Food Craving Questionnaire-State; FCT, Food Challenge Task; NS, Not Specified; SUD, Substance Use Disorders; TD task, temporal discounting task; SSRls, serotonin reuptake inhibitors; tDCS, transcranial direct current stimulation; VAS, Visual Analog Scales.