Exploring the Full Body Representation in Anorexia Nervosa and Bulimia Nervosa
The ability to mentally recall a motor act without any overt movement is called motor imagery (MI). The movement simulation that occurs on a cognitive level can be seen as a way in which we express the mental representation of the body in action. MI tasks can be used as a proxy for the exploration of the mental representations of the body. Interestingly, MI tasks differ in the degree of action monitoring required to resolve the task. More in detail, we can allocate MI tasks along a continuum that goes from more implicit MI tasks (less action monitoring required for the resolution of the task) to more explicit MI tasks (more action monitoring required for the resolution of the task). Eating disorders such as anorexia nervosa (AN) and bulimia nervosa (BN) are both characterized by body image distortion and impairments (i.e. overestimation of the perceived body), however, on a different state of the physical body: on one hand we have a highly malnourished body, on the other hand, we might have a healthy-looking body or an overweight body. As above mentioned, MI tasks can be used as a proxy for the exploration of the mental representations of the body and people affected by AN and BN show impairment on their imagined body. This means that people affected by AN and BN might respond differently when assessed for their MI abilities. We hypothesize that people affected by AN might show greater impairment in their motor imagery abilities because of the greater discrepancy between the physical body (malnourished) and the mental body representation in comparison to people affected by BN, who usually have a health weight, even an altered body representation. Nevertheless, we might expect the alteration of body representation not strictly linked to the physical body dimensions, in the case of no difference between AN and BN. This would be of relevance for the creation of rehabilitative programs.
• Female;
• age between 18 and 55 years old;
• diagnosis of AN (restrictive and binge-purging type\*), as per DSM V criteria (APA, 2013);
• BMI ≤ 17,5 Kg/m2;
• right-handed (i.e. Edinburgh Handedness Inventory (EHI) (Veale, 2014)).
‣ Restricting type: During the last 3 months, the individual has not engaged in recurrent episodes of binge eating or purging behaviour (i.e. self-induced vomiting or the misuse of laxatives, diuretics, or enemas). This subtype describes presentations in which weight loss is accomplished primarily through dieting, fasting, and/or excessive exercise.
⁃ Binge-eating/purging type: During the last 3 months, the individual has engaged in recurrent episodes of binge eating or purging behaviour (i.e. self-induced vomiting or the misuse of laxatives, diuretics, or enemas).
• female;
• age between 18 and 55 years old;
• diagnosis of BN, as per DSM V criteria (APA, 2013);
• BMI ≤ 17,5 Kg/m2 or BMI ≥ 30 Kg/m2;
• right-handed (i.e. EHI (Veale, 2014)).
• female;
• age between 18 and 55 years old;
• right-handed (i.e. EHI (Veale, 2014)).