Anorexia NervosaSESTODITO_ANNCT06316674
The Malleability of Body Representation in Anorexia Nervosa: the Sixth Finger Illusion
An observational study of Anorexia Nervosa, run by Istituto Auxologico Italiano at 1 site in Italy.
Trial 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… Read more about this study
- Who is it for?
- Ages 18 to 55 years, women onlyHealthy volunteers can take part
- Conditions the study is for
- Anorexia Nervosa
- What is being tested?
- sixth finger illusion
- Type of treatment
- Lifestyle or therapy programme
- How many people
- 60 participants
- Where
- 1 siteItaly
- Study dates
- 1 May 2023to 30 Apr 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- Women only
- Healthy volunteers accepted
- Adult
Study population: Female Anorexia Nervosa patients and female healthy controls
Who may be able to join
- female
- 18-55 years
- bmi ≤ 17.5 Kg/m2 for AN and BMI between 18.5 Kg/m2 e 25 Kg/m2 for healthy controls
Who cannot join
- psychopathologies related to psychosis or brain injury lesions
Trial locations and contacts
1 site in 1 country.
About this study
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.
Read more
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.
Read the detailed description
The ability to imagine our body in our mind is called body representation. This ability is grounded in sensory and perceptual process and it is crucial to plan action, to interact with the environment and so on. Body representation can be explored using behavioural tasks such as motor imagery tasks as well as body illusions.
Evidence from healthy individuals shows that we depend on physical constraints when we imagine actions we can do with our body: we are faster and more accurate in imagining an action that we can really perform. This phenomenon is called "biomechanical constraints effect" and it is an index that our brain is performing motor imagery. When a lesion occurs to the spinal cord, for example, this effect is not present anymore, supporting the idea that what occurs in our brain is strongly dependent on what we can do in the real word. This dependency from the real word, however, does not mean that the representation of the body in the mind is an exact copy of the physical body. For example, findings from experiments using body illusions show that we have a distorted representation of our body, even in absence of any lesion. Overall, evidence from body illusions in healthy individuals shows that we tend to overestimate features when we imagine our body, width in particular compared to length and height.
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.
Recent studies suggest that body representation is quite different in conditions that affect the body even in absence of central nervous system or brain impairments, such as anorexia nervosa. In patients affected by anorexia nervosa, motor imagery does not occur, and patients treat their body like it is an object. Similarly, when subjected to illusions of ownership, patients with anorexia nervosa experience the illusion more strongly than healthy individuals.
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
- Being tested
- sixth finger illusion
- Medical subject headings
- Anorexia Nervosa
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
sixth finger illusionBehavioural
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.
| Study group | Role | What they receive |
|---|---|---|
| Anorexia Nervosa (AN) | People affected by AN (DSM5); female, age 18-55, BMI ≤ 17.5 Kg/m2 Receives: Behavioral: sixth finger illusion | |
| Healthy controls (HC) | female, age 18-55, BMI between 18.5 Kg/m2 and 25 Kg/m2 Receives: Behavioral: sixth finger illusion |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sixth finger illusion questionnaire
Participants are asked to answer to a 6 questions questionnaire based on a likert scale
Measured: Through study completion, an average of 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Mar 2024
- Study start1 May 2023
- Primary completion30 Apr 2024
- Study completion30 Apr 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (8)Papers the sponsor has linked to this study.
- Other trials for Anorexia NervosaStudies of the same condition, open and under way.
- More trials run by Istituto Auxologico ItalianoThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- Istituto Auxologico Italiano
- Sponsor type
- University, hospital or other
- Collaborators
- Heriot-Watt University, Birkbeck, University of London, Catholic University of the Sacred Heart
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06316674
- Sponsor's protocol ID
- 03C304
- Acronym
- SESTODITO_AN
- Status last verified
- Oct 2024
- First submitted
- 28 Feb 2024
- Last updated
- 8 Oct 2024
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
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.
PubMed 33392694Brusa 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.
PubMed 37800303de 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.
PubMed 19786038Eshkevari 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.
PubMed 22017964Eshkevari 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.
PubMed 24243423Fiori 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.
PubMed 23672438Holmes 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.
PubMed 16467906Scarpina 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.
PubMed 35033502
Study at a glance
From the registry record, last updated by the sponsor on 8 Oct 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Malleability of Body Representation in Anorexia Nervosa: the Sixth Finger Illusion
- ClinicalTrials.gov ID
- NCT06316674
- Acronym / sponsor ID
- SESTODITO_AN / 03C304
- Conditions
- Anorexia Nervosa
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- Istituto Auxologico ItalianoUniversity, hospital or other
- Collaborators
- Heriot-Watt University, Birkbeck, University of London, Catholic University of the Sacred Heart
- Study start
- 1 May 2023 (actual)
- Primary completion
- 30 Apr 2024 (actual)
- Study completion
- 30 Apr 2024 (actual)
- First posted
- 18 Mar 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
The ability to imagine our body in our mind is called body representation. This ability is grounded in sensory and perceptual process and it is crucial to plan action, to interact with the environment and so on. Body representation can be explored using behavioural tasks such as motor imagery tasks as well as body illusions.
Evidence from healthy individuals shows that we depend on physical constraints when we imagine actions we can do with our body: we are faster and more accurate in imagining an action that we can really perform. This phenomenon is called "biomechanical constraints effect" and it is an index that our brain is performing motor imagery. When a lesion occurs to the spinal cord, for example, this effect is not present anymore, supporting the idea that what occurs in our brain is strongly dependent on what we can do in the real word. This dependency from the real word, however, does not mean that the representation of the body in the mind is an exact copy of the physical body. For example, findings from experiments using body illusions show that we have a distorted representation of our body, even in absence of any lesion. Overall, evidence from body illusions in healthy individuals shows that we tend to overestimate features when we imagine our body, width in particular compared to length and height.
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.
Recent studies suggest that body representation is quite different in conditions that affect the body even in absence of central nervous system or brain impairments, such as anorexia nervosa. In patients affected by anorexia nervosa, motor imagery does not occur, and patients treat their body like it is an object. Similarly, when subjected to illusions of ownership, patients with anorexia nervosa experience the illusion more strongly than healthy individuals.
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.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Anorexia Nervosa (AN) | – | Behavioral: sixth finger illusionPeople affected by AN (DSM5); female, age 18-55, BMI ≤ 17.5 Kg/m2 |
| Healthy controls (HC) | – | Behavioral: sixth finger illusionfemale, age 18-55, BMI between 18.5 Kg/m2 and 25 Kg/m2 |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Female Anorexia Nervosa patients and female healthy controls
Key inclusion criteria (3 listed)
- female
- 18-55 years
- bmi ≤ 17.5 Kg/m2 for AN and BMI between 18.5 Kg/m2 e 25 Kg/m2 for healthy controls
Key exclusion criteria (1 listed)
- psychopathologies related to psychosis or brain injury lesions
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| sixth finger illusionParticipants 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. | Behavioural | Anorexia Nervosa (AN), Healthy controls (HC) |
Primary outcome
Sixth finger illusion questionnaire
Time frame: Through study completion, an average of 1 year
Participants are asked to answer to a 6 questions questionnaire based on a likert scale
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Oct 2024.
- Background: PubMed 33392694Brusa 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.
- Background: PubMed 37800303Brusa 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.
- Background: PubMed 19786038de 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.
- Background: PubMed 22017964Eshkevari 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.
- Background: PubMed 24243423Eshkevari 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.
- Background: PubMed 23672438Fiori 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.
- Background: PubMed 16467906Holmes 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.
- Background: PubMed 35033502Scarpina 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.
- Individual participant dataSharing planned: Undecided
Related trials for Anorexia Nervosa
Not yet recruiting
Be Body Brave: Digital Written Exposure Therapy for Eating Disorders
Eating Disorders
RecruitingObservational study
Speech Groups for Children Living With a Sibling Who Suffers From Anorexia Nervosa
Anorexia Nervosa
Enrolling by invitation
Sleep and Activity For Eating Disorders
Eating Disorders, Anorexia Nervosa
Not yet recruitingObservational study
Biomarkers in EV Associated With Marrow Adiposity in Anorexia
Anorexia Nervosa Restricting Type, Anorexia Nervosa (DSM-IV Revised Criteria)
Active, not recruiting
Targeting Social Function in Anxiety and Eating Disorders
Eating Disorders, Anorexia Nervosa
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Anorexia Nervosa, run by Istituto Auxologico Italiano at 1 site in Italy.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 8 Oct 2024. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sixth finger illusion questionnaire (time frame: Through study completion, an average of 1 year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06316674, which also lists 8 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Oct 2024.