Food craving, food choice and consumption: The role of impulsivity and sham-controlled tDCS stimulation of the right dlPFC.

BACKGROUND: Impulsivity has been found to be associated with overeating and obesity. Transcranial direct current stimulation (tDCS) may enhance inhibitory control while reducing food craving and intake. Thus, the aim of the present study was to investigate whether tDCS stimulation modifies food choice, craving and consumption as a function of trait impulsivity.

METHODS: Forty-two predominantly healthy-weight women received active tDCS stimulation to the right dorsolateral prefrontal cortex and sham stimulation in a within participant design. Trait impulsivity was measured with a short form of the Barratt Impulsiveness Scale. Participants completed a computerized food-choice task, during which their mouse movements were traced. Current food craving was measured by a modified version of the Food Cravings Questionnaire-State as well as by desire to eat ratings for food pictures. Food intake was measured in a taste test.

RESULTS: There were no tDCS effects on any of the dependent variables. Trait impulsivity (and non-planning impulsivity in particular) was positively associated with higher calorie intake in the taste test, irrespective of tDCS stimulation.

CONCLUSION: The current findings question the efficacy of single-session tDCS stimulation of the right dLPFC to reduce food craving, high caloric food choice and calorie intake in non-selected, predominantly healthy weight women. However, they do support the idea that trait impulsivity is related to overeating and, therefore, may be a risk factor for obesity. Future research needs to specify which appetitive behaviors can be modulated by brain stimulation and which populations might profit from it the most.