Exploring the Full Body Representation in Anorexia Nervosa and Bulimia Nervosa

Summary

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.

Conditions

• Anorexia Nervosa/Bulimia

Interventions

BEHAVIORAL

Mental Motor Chronometry (MMC) Task Hands and Feet and Whole Body

The MMC will be used as a measure of MI and it is adapted for use in hands, feet, and the whole body as well as for online experimentation. The task is comprised of two conditions, MI, and motor execution, in which respectively participants will be asked to imagine and execute a movement sequence with both hands and feet and the whole body. Hand movements: index and thumb opposition; thumb extension from the fist; middle finger crossed on the index finger; and extension of the index and the little fingers. Foot movements: foot internal rotation, foot external rotation, foot dorsiflexion, and foot plantarflexion. Whole-body movements: take a small bow, lift arms over the head and stand on the tips of the toes (stretch), extend hands forward and lower the backside (squats) and a small jump. The types of movements required to be executed by participants are simple and do not require much energy. Therefore, people affected by AN and BN should be able to perform them without problems.

Sponsors & Collaborators

• University of Turin, Italy

  collaborator OTHER

• Open University

  collaborator OTHER

• Heriot-Watt University

  collaborator OTHER

• Catholic University of the Sacred Heart

  collaborator OTHER

• Istituto Auxologico Italiano

  lead OTHER

Eligibility

Min Age

18 Years

Max Age

55 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-06-18

Primary Completion

2025-06-15

Completion

2026-05-31

Countries

• Italy

Study Locations