Neural Correlates of Autistic Individuals With Anorexia Nervosa

Recruiting

• Conditions: Autism; Anorexia Nervosa

• Registration Number: NCT07098156
• Lead Sponsor: University of Aberdeen

Brief Summary

Masking is a behaviour or strategy used by many Autistic people to appear non-Autistic and blend in with a neurotypical society. The goal of this observational study is to understand the relationship between masking, anorexia nervosa symptoms and brain structure in Autistic people. The main questions this study aims to answer are:

* Do Autistic individuals with anorexia nervosa show differences in structure or function of the brain relation to Autistic individuals without anorexia nervosa?

* Do Autistic individuals with anorexia nervosa display higher levels of masking than Autistic individuals without anorexia nervosa?

* Are there indeed relationships between levels of masking, anorexia nervosa symptoms and brain structure in Autistic people?

Researchers will compare Autistic people without anorexia nervosa to Autistic people with anorexia nervosa to see if there are differences between groups. Participants will:

* Complete a series of questionnaires focused on eating disorder symptoms, autistic traits, autistic masking and psychological well-being

* Undergo an MRI scan at the Aberdeen Royal Infirmary

Detailed Description

Autism is a neurodevelopmental condition and presents as a distinct neurotype, characterised by a wide range of social and behavioural differences, including divergences in cognitive thinking and methods of communication. Autism shares significant behavioural features with restrictive eating disorders (EDs) such as anorexia nervosa (AN). Those with AN exhibit significantly elevated levels of Autistic characteristics, ranging between 2%-53%. Importantly, a characteristic shown by some Autistic people is the presence of masking, a term describing a strategy used by Autistic people, whether conscious or unconscious, to 'blend in' with neurotypical peers. While initially overlooked, it is now well-known that masking behaviour can produce detrimental effects on Autistic individuals' mental health. The presence of masking behaviour has been associated with increased levels of physical and mental exhaustion, anxiety/depression, and importantly, an increased presence of EDs.

The Eating Disorder and Autism Collaborative (EDAC) used an arts-based method called Photovoice to capture the experiences of Autistic individuals with lived/living experience of an ED. Participants commented on the how an ED can serve as a means to mask or camouflage within a neurotypical world (e.g., an Autistic person may use restrictive eating or excessive exercise as a means with which to 'fit in' with their peers). Magnetic resonance imaging (MRI) research can assist in understanding which regions of the brain are associated with masking behaviour, and whether there are differences in brain function/structure in Autistic individuals with versus without an ED.

Structural magnetic resonance imaging (MRI) research reports similarities in brain structure between those with AN and Autistic individuals, reporting differential structure of the amygdala, cerebellum, insula, cingulate cortex, as well as orbitofrontal and frontal cortex in both groups. Shared differences extend to neuroanatomical parameters essential for brain development and connectivity, such as cortical thickness and surface area. Further, there are no studies investigation structural correlates with masking behaviour, or distinct aspects of social camouflage such as masking, assimilation and compensation. Further research is necessary to disentangle the complex relationship between Autistic characteristics and symptomatology associated with restrictive EDs.

The investigators believe that by further understanding the brain structure and function associated with ED symptomatology and masking behaviour in Autistic individuals can assist with the development of novel or tailored interventions for EDs in this community.

Study Timeline

• Status Verified: 2025-07
• Study Start: 2025-07-01
• Study First Submitted: 2025-07-16
• Study First Submitted QC: 2025-07-24
• Last Update Submitted: 2025-07-24
• Study First Posted: 2025-08-01
• Last Update Posted: 2025-08-01
• Primary Completion: 2026-01
• Study Completion: 2026-01-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

Healthy Autistic Individuals (Autistic Controls) must:

• Be aged 25-45 years
• Be Autistic (clinically diagnosed and/or have an Autism Quotient (AQ-10) score of ≥6)
• Be able to provide informed consent for the study
• Be able to read, understand and respond to questionnaires in English
• Have no history of an eating disorder
• Willing to have an MRI scan in Aberdeen

Autistic Individuals with anorexia nervosa must:

• Be aged 25-45 years
• Be Autistic (clinically diagnosed and/or have an AQ-10 score of ≥6)
• Be able to provide informed consent to the study
• Be able to read, understand and respond to questionnaires in English
• Have a diagnosis of anorexia nervosa or a body mass index of <18.5
• Willing to have an MRI scan in Aberdeen

Exclusion Criteria

Individuals are not eligible for the study if they:

• Are aged <25 or >45 years
• Are not Autistic or not clinically diagnosed as Autistic and have an AQ-10 score of <6
• Are diagnosed with an eating disorder other than anorexia nervosa
• Have a history of brain injury (e.g., stroke)
• Be unable to provide informed consent for the study
• Have contraindications to MRI scanning, such has implantable cardiac devices
• Are unable to read, understand and respond to questionnaires in English
• As participants will need to consent to the study and complete questionnaires by themselves, individuals with intellectual disability will be excluded from this study

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Associations Between Masking, Anorexic Symptoms and Brain Structure	From enrolment to single research visit (up to 30 weeks).	To determine if there are associations between the levels of masking, eating disorder symptomatology and brain structure in Autistic individuals via multiple 3-path mediation analysis established using generalised linear models.; Levels of masking will comprise of total and scores on the Camouflaging Autistic Traits Questionnaire, which contains 25 statements. All statements are scored on a scale of 1-7, with a scoring range of 25-175. Higher scores reflect greater camouflaging, with a threshold score of consisting of 100 or greater.; Levels of eating disorder symptomatology will comprise of the Eating Disorder Examination Questionnaire, which contains 28 statements. Total scores range from 0-6, with a clinical cut-off score of 2.8 for women, and 1.68 for men.; Brain structure will be measured using surface and subcortical parcellations (in mm\^3) acquired from Freesurfer.
Levels of Masking	From enrolment to single research visit (up to 30 weeks).	To determine whether Autistic individuals with anorexia nervosa exhibit higher masking behaviour than Autistic individuals without anorexia nervosa via 2-sample t-tests on total and subscale scores on the Camouflaging Autistic Traits Questionnaire. The Camouflaging Autistic Traits Questionnaire contains 25 statements relating to three subcategories of camouflaging (9 statements for the compensation subscale; 8 statements for the masking subscale; 8 statements for the assimilation subscale). All statements are scored on a scale of 1-7, and the scoring range on this measurement ranges from 25 to 175. Higher scores reflect greater camouflaging, with a threshold score of high camouflaging consisting of a score of 100 or greater.
Structural and Functional Brain Differences	From enrolment to single research visit (up to 30 weeks).	To examine whether Autistic individuals with anorexia nervosa exhibit differences in brain structure or function relative to Autistic individuals without anorexia nervosa via 2-sample t-tests. Brain structure will be measured using surface and subcortical parcellations (in mm\^3) acquired from Freesurfer. Brain functional connectivity at resting state will be measured using bivariate correlations of mean BOLD signal across pairs of regions of interest, converted to normally distributed scores using Fisher's transformation.

Trial Locations

Locations (2)

Lilian Sutton Building; 🇬🇧 Aberdeen, Aberdeen City, United Kingdom

NHS Grampian Eating Disorder Services; 🇬🇧 Aberdeen, Aberdeen City, United Kingdom