Pilot Study of an Intervention Involving Cognitive Training and tDCS in Morbidly Obese Subjects

The study aims to: 1) investigate the effects of cognitive training (CT) and combined CT and transcranial direct current stimulation (tDCS) on food intake and 2) to further understand its neuropsychological and neurophysiological basis (i.e. EEG) as well as its impact in endocannabinoids (EC) in a sample of morbidly obese patients seeking for a gastric bypass surgery

The study will explore the impact of a 4-day intervention with either CT (Active control condition) or CT+tDCS (Active condition) stimulation on food intake in a sample of morbidly obese patients, as measured by dietary assessments the week before, during and the week after the intervention. Additionally, to further understand the neuropsychological and neurophysiological basis of its impact, measures of executive function and attention performance and EEG recordings, respectively, will be collected. Furthermore, we will explore the effect of the intervention on endocannabinoids previously related to eating behaviour. The Active Control condition will receive sham stimulation together with CT, through a computerized cognitive training platform (Guttmann NeuropersonalTrainer), including different tasks with designed to train executive functions and attention. Each session will last approximately 30-40 min. The Active condition will receive tDCS stimulation (20 min, multichannel with an excitatory target over the r-dlPFC) together with CT (same as for the Active Control condition). Participants will undergo a basal (the week before intervention) and a post treatment assessments (the day after finishing the intervention) that will include medical history, blood testing, anthropometric measures, a cognitive assessment battery and a 4-day dietary assessment.