Repeated net-tDCS of the hypothalamus appetite-control network reduces inhibitory control and sweet food intake in persons with overweight or obesity

BackgroundReduced inhibitory control is associated with obesity and neuroimaging studies indicate that diminished prefrontal cortex activity influence eating behavior and metabolism. The hypothalamus regulates energy homeostasis and is functionally connected to cortical and subcortical regions especially the frontal areas. ObjectivesWe tested network-targeted transcranial direct current stimulation (net-tDCS) to influence the excitability of brain regions involved in appetite control. MethodsIn a randomized, double-blind parallel group design, 44 adults with overweight or obesity (BMI 30.6 kg/m2, 52.3 % female) received active (anodal or cathodal) or sham 12-channel net-tDCS on the hypothalamus appetite-control network for 25 minutes on three consecutive days while performing a Stop-Signal-Task to measure response inhibition. Before and after stimulation, state questionnaires assessed changes in desire to eat and food craving. Directly after stimulation, participants received a breakfast buffet to evaluate ad-libitum food intake. An oral glucose tolerance test was conducted at follow-up. Resting-state functional MRI was obtained at baseline and follow-up. ResultsThe Stop-Signal Reaction Time (SSRT) was shorter in both active groups versus sham, indicating improved response inhibition. Additionally, a stronger increase in hypothalamic functional connectivity was associated with shorter SSRT. Caloric intake of sweet food was lower in the anodal group versus sham, but no main effects between groups were observed on total and macronutrient intake, food craving ratings and desire to eat. At follow-up, no differences were observed between groups on peripheral metabolism. ConclusionOur study suggests that modulating hypothalamic functional network connectivity patterns via net-tDCS may improve food choice and inhibitory control. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=100 SRC="FIGDIR/small/24318873v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@1869c1forg.highwire.dtl.DTLVardef@73e837org.highwire.dtl.DTLVardef@192b3bcorg.highwire.dtl.DTLVardef@5632d0_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIActive net-tDCS groups showed better inhibitory control compared to the sham group. C_LIO_LIStronger increase in hypothalamic functional connectivity associated with better inhibitory control after active net-tDCS. C_LIO_LINo differences were found between the active net-tDCS and sham groups for total kilocaloric intake. C_LIO_LIAnodal net-tDCS showed lower sweet food intake compared to the sham group. C_LI