The Malleability of Body Representation in Anorexia Nervosa: the Sixth Finger Illusion

NCT06316674 | Completed

• 1 other identifier: 03C304
• Study Type: observational
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Body representation can be explored using behavioural tasks such as motor imagery tasks as well as body illusions. In both cases, evidence from studies on healthy individuals as well as patients with lesions to the central nervous system show that body representation is not set in stone: how we imagine our bodies is a dynamic and continuously updated process, to reflect changes in our own body as well as the environment. In anorexia nervosa the representation of the body is very different from that of healthy individuals: the representation is more malleable, and easier to manipulate, while at the same time being more detached from physical constraints. These features of body representation in anorexia nervosa might contribute to the persistence of symptoms and to relapses too. Body representation has clear implications for treatment of anorexia nervosa too. The study aims at evaluating the presence of differences in the malleability of the body representation, explored through the illusion of the sixth finger, between a group of people with AN and a group of normal weight people, taking into account the biomechanical constraints that characterize the physical and mentally represented body.

Conditions

Anorexia Nervosa

Outcome Measures

Primary Outcomes (1)

• Sixth finger illusion questionnaire

  Participants are asked to answer to a 6 questions questionnaire based on a likert scale

  Through study completion, an average of 1 year

Study Arms (2)

Anorexia Nervosa (AN)

People affected by AN (DSM5); female, age 18-55, BMI ≤ 17.5 Kg/m2

Behavioral: sixth finger illusion

Healthy controls (HC)

female, age 18-55, BMI between 18.5 Kg/m2 and 25 Kg/m2

Behavioral: sixth finger illusion

Interventions

sixth finger illusion BEHAVIORAL

Participants will undertake the sixth finger illusion that is a body illusion which elicits the presence of an extra numerary finger due to visuo-tactile stimulation.

Anorexia Nervosa (AN); Healthy controls (HC)

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

Female Anorexia Nervosa patients and female healthy controls

You may qualify if:

• female
• years
• bmi ≤ 17.5 Kg/m2 for AN and BMI between 18.5 Kg/m2 e 25 Kg/m2 for healthy controls

You may not qualify if:

• psychopathologies related to psychosis or brain injury lesions

Sponsors & Collaborators

• Istituto Auxologico Italiano: lead
• Heriot-Watt University: collaborator
• Birkbeck, University of London: collaborator
• Catholic University of the Sacred Heart: collaborator

Study Sites (1)

Istituto Auxologico italiano IRCSS

Milan, Italy

Location

Related Publications (8)

• Brusa F, Kretzschmar L, Magnani FG, Turner G, Garraffa M, Sedda A. Talking with hands: body representation in British Sign Language users. Exp Brain Res. 2021 Mar;239(3):731-744. doi: 10.1007/s00221-020-06013-4. Epub 2021 Jan 3.

  PMID: 33392694 BACKGROUND

• Brusa F, Suphi Erden M, Sedda A. Exploring the role of disgust in hands and feet laterality judgement tasks. Q J Exp Psychol (Hove). 2024 Jul;77(7):1418-1429. doi: 10.1177/17470218231207336. Epub 2023 Nov 3.

  PMID: 37800303 BACKGROUND

• de Vignemont F. Body schema and body image--pros and cons. Neuropsychologia. 2010 Feb;48(3):669-80. doi: 10.1016/j.neuropsychologia.2009.09.022. Epub 2009 Sep 26.

  PMID: 19786038 BACKGROUND

• Eshkevari E, Rieger E, Longo MR, Haggard P, Treasure J. Increased plasticity of the bodily self in eating disorders. Psychol Med. 2012 Apr;42(4):819-28. doi: 10.1017/S0033291711002091. Epub 2011 Oct 5.

  PMID: 22017964 BACKGROUND

• Eshkevari E, Rieger E, Longo MR, Haggard P, Treasure J. Persistent body image disturbance following recovery from eating disorders. Int J Eat Disord. 2014 May;47(4):400-9. doi: 10.1002/eat.22219. Epub 2013 Nov 18.

  PMID: 24243423 BACKGROUND

• Fiori F, Sedda A, Ferre ER, Toraldo A, Querzola M, Pasotti F, Ovadia D, Piroddi C, Dell'Aquila R, Redaelli T, Bottini G. Motor imagery in spinal cord injury patients: moving makes the difference. J Neuropsychol. 2014 Sep;8(2):199-215. doi: 10.1111/jnp.12020. Epub 2013 May 15.

  PMID: 23672438 BACKGROUND

• Holmes NP, Spence C. The body schema and the multisensory representation(s) of peripersonal space. Cogn Process. 2004 Jun;5(2):94-105. doi: 10.1007/s10339-004-0013-3.

  PMID: 16467906 BACKGROUND

• Scarpina F, Bastoni I, Villa V, Mendolicchio L, Castelnuovo G, Mauro L, Sedda A. Self-perception in anorexia nervosa: When the body becomes an object. Neuropsychologia. 2022 Feb 10;166:108158. doi: 10.1016/j.neuropsychologia.2022.108158. Epub 2022 Jan 14.

  PMID: 35033502 BACKGROUND

MeSH Terms

Conditions

Anorexia Nervosa

Condition Hierarchy (Ancestors)

Feeding and Eating Disorders; Mental Disorders

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 28, 2024
• First Posted: March 18, 2024
• Study Start: May 1, 2023
• Primary Completion: April 30, 2024
• Study Completion: April 30, 2024
• Last Updated: October 8, 2024

Record last verified: 2024-10

Locations

IT (1)