The effect of high-definition transcranial direct current stimulation on inhibitory control.

Impairment of inhibitory control in EDs is suggested to play a key role in EDs symptomatology: binge-eating/purging types exhibit poor inhibitory control, associated with overall hypo-activity of the right dorsolateral prefrontal cortex (rDLPFC), whereas restrictive types show excessive inhibitory control and a corresponding hyperactivity of the rDLPFC. In this regard, high definition transcranial direct current stimulation (HD-tDCS) - used to modulate the excitability of cortical structures - seems a promising avenue for future research and interventions. The administration of HD-tDCS over the DLPFC may alter the underlying neural mechanisms of inhibitory control and related eating behaviors across (subclinical) EDs subtypes. We will first carry out a large-scale study in 160 healthy controls to determine the effect of different tDCS-montages on inhibitory control, assessed by means of two inhibition tasks (i.e., Stop-Signal task and Go-NoGo task) performed prior and during the intervention. In this mixed design, participants will be randomly assigned to one of the following tDCS-montages: one session of (1) anodal rDLPFC 4x1 HD-tDCS, (2) anodal left DLPFC 4x1 HD-tDCS, (3) anodal rDLPFC bilateral HD-tDCS, (4) anodal left DLPFC bilateral HD-tDCS, and (5) sham DLPFC HD-tDCS. The obtained findings will serve as input for our upcoming studies in subclinical EDs, intending to improve the prevention and treatment of EDs.