P113 Modulation of food and body weight implicit attitudes with non-invasive brain stimulation techniques

Abstract

Introduction Non-invasive brain stimulation (NiBS) techniques have been increasingly used in experimental and clinical studies on food-related behaviours and psychopathologies. However, results are still controversial on what concerns the neural mechanisms underlying eating disorders and the possibility to modulate eating behaviours with NiBS techniques in healthy and clinical populations. This study investigates these issues assessing the effects of transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) on attitudes towards food in healthy volunteers and patients with eating disorders. Methods & results In experiment 1, we applied TMS on the medial prefrontal cortex (mPFC) of healthy participants and showed that this area was causally involved in monitoring implicit attitudes towards food measured with the implicit association test (IAT). In experiment 2, we are assessing in healthy volunteers and patients with anorexia or bulimia nervosa the effect of applying anodal tDCS over mPFC and extrastriate body area (EBA) on attitudes towards food and underweight or overweight body shapes, as measured by IATs. Preliminary results on a healthy sample show no significant modulation of IATs by mPFC- or EBA-tDCS, in particular, differently from mPFC-TMS, mPFC-tDCS does not affect IAT on food preference. However, we expect different behavioural performances and tDCS-related modulations in the clinical population. Conclusion Taken together, our results could shed light on the effects of different NiBS protocols on implicit attitudes in eating disorders. In particular, using the same behavioural paradigm with different populations and NiBS techniques we aim at clarifying the role of different target areas which could be selected for clinical trials in future research.