CBT Effects on Neural, Physiological, and Attentional Responses in Anorexia Nervosa

NCT07037017 | Recruiting

• 1 other identifier: AN-CBT-EEG-2025
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized controlled trial investigates the neurophysiological, physiological, and attentional effects of Cognitive-Behavioral Therapy (CBT) in individuals with restrictive-type anorexia nervosa (AN). The study compares two groups: one receiving a 12-week CBT intervention, and one placed on a waitlist (no active treatment during the study period). All participants undergo pre- and post-intervention assessments using electroencephalography (EEG), galvanic skin response (GSR), and eye-tracking while exposed to visual stimuli related to food, body image, and self-appearance. The primary outcomes include neural changes in attention and emotional processing (P300, LPP, frontal alpha asymmetry), physiological arousal (skin conductance), and visual attention biases (fixation duration and gaze distribution). The aim is to determine whether CBT leads to measurable improvements in neurobiological and attentional mechanisms related to body image disturbance and food-related anxiety in AN, contributing to biomarker-informed psychotherapy approaches.

Conditions

Eating Disorders (Excluding Anorexia Nervosa)

Keywords

Cognitive Behavioral Therapy (CBT); EEG; Eye-Tracking; Galvanic Skin Response (GSR); Body Image

Outcome Measures

Primary Outcomes (5)

• Change in EEG P300 amplitude in response to body image stimuli

  P300 amplitudes will be extracted from EEG data during visual exposure to body image stimuli. Reduced amplitudes post-CBT are hypothesized to indicate reduced attentional salience and hyperfocus on appearance-related cues. P300 amplitudes will be extracted from EEG data during visual exposure to body image stimuli. Reduced amplitudes post-CBT are hypothesized to indicate reduced attentional salience and hyperfocus on appearance-related cues.

  aseline and Week 12

• Change in Late Positive Potential (LPP) amplitude to body and food stimuli

  LPP amplitudes will be measured during viewing of thin, overweight, and food-related images. A reduction post-CBT suggests decreased sustained emotional reactivity to distressing visual input.

  Baseline and Week 12

• Change in frontal alpha asymmetry during self-image viewing

  Frontal alpha asymmetry (FAA), computed from EEG data, will be used to index emotional regulation. An increase in left-dominant FAA is expected post-CBT, reflecting enhanced emotional control and positive self-perception.

  Baseline and Week 12

• Change in skin conductance response (SCR) to body and food stimuli

  Skin conductance responses will be measured via GSR during visual exposure to self-body, other-body, and food stimuli. Decreased SCR amplitudes post-CBT will indicate reduced physiological arousal and distress.

  Baseline and Week 12

• Change in fixation duration on weight-related body areas

  Eye-tracking will assess gaze fixation duration on areas of interest (waist, thighs, stomach). Post-CBT reductions in fixation on these regions suggest reduced attentional bias toward body dissatisfaction zones.

  Baseline and Week 12 Baseline and Week 12

Secondary Outcomes (6)

• Change in Eating Disorder Examination Questionnaire (EDE-Q) scores

  Baseline and Week 12

• Change in Beck Depression Inventory-II (BDI-II) scores

  Baseline and Week 12

• Change in Beck Anxiety Inventory (BAI) scores

  Baseline and Week 12

• Change in Yale-Brown Obsessive Compulsive Scale - Body Dysmorphic Disorder Version (YBOCS-BDD) scores

  Baseline and Week 12

• Change in Cognitive Emotion Regulation Questionnaire (CERQ) scores

  Baseline and Week 12

Study Arms (2)

CBT Intervention Group

EXPERIMENTAL

Participants diagnosed with restrictive-type anorexia nervosa will receive 12 weekly individual Cognitive-Behavioral Therapy (CBT) sessions. Each session will last approximately 60 minutes and be delivered by a trained therapist. The CBT protocol targets body image distortion, cognitive restructuring of maladaptive beliefs, exposure to food-related stimuli, emotional regulation strategies, and behavioral experiments to reduce avoidance. Pre- and post-treatment neurophysiological (EEG), physiological (GSR), and attentional (eye-tracking) assessments will be conducted.

Behavioral: Cognitive-Behavioral Therapy

Waitlist Control Group

NO INTERVENTION

Participants diagnosed with restrictive-type anorexia nervosa will be placed on a waitlist and will not receive any structured psychological intervention during the 12-week study period. They will complete the same neurophysiological (EEG), physiological (GSR), and attentional (eye-tracking) assessments at baseline and at the 12-week follow-up.

Interventions

Cognitive-Behavioral Therapy BEHAVIORAL

Manualized 12-week CBT protocol focused on reducing body image disturbance, distorted beliefs about food and appearance, and avoidance behaviors in individuals with anorexia nervosa. The intervention incorporates psychoeducation, cognitive restructuring, emotional regulation, food exposure, and body image work.

CBT Intervention Group

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Female participants aged 18 to 35
• Meeting DSM-5 diagnostic criteria for restrictive-type anorexia nervosa
• Body Mass Index (BMI) between 15.0 and 18.5
• Medically stable to participate in psychological and neurophysiological assessments
• Willingness to participate in weekly therapy sessions (for the CBT group) and to complete pre- and post-assessments
• Ability to provide informed consent

You may not qualify if:

• Current or past diagnosis of bulimia nervosa, binge-eating disorder, or other eating disorders
• Presence of comorbid severe psychiatric disorders (e.g., psychosis, bipolar disorder, substance use disorder)
• History of neurological illness or traumatic brain injury
• Use of psychotropic medication within the last 6 weeks
• Prior participation in structured Cognitive-Behavioral Therapy for an eating disorder
• Pregnancy
• Visual or neurological impairments that would prevent accurate EEG, GSR, or eye-tracking recordings

Sponsors & Collaborators

• Istanbul Nisantasi University: lead
• Uskudar University: collaborator
• Beykoz University: collaborator

Study Sites (1)

Üsküdar University Neuro Marketing Lab.

Istanbul, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Feeding and Eating Disorders

Interventions

Cognitive Behavioral Therapy

Condition Hierarchy (Ancestors)

Signs and Symptoms, Digestive; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Mental Disorders

Intervention Hierarchy (Ancestors)

Behavior Therapy; Psychotherapy; Behavioral Disciplines and Activities

Study Officials

• Gökben Hızlı Sayar, Professor

  Üsküdar University

  STUDY CHAIR

• Eda Yılmazer, Phd

  Beykoz University

  STUDY DIRECTOR

Central Study Contacts

Metin Çınaroğlu, Phd

CONTACT

00905324732070; metincinaroglu@gmail.com

Selami Varol Ülker, Phd

CONTACT

00905364360941; selamivarol.ulker@uskudar.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: A two-arm, parallel-group, randomized controlled trial comparing the effects of a 12-week Cognitive-Behavioral Therapy program versus a waitlist control in individuals with restrictive-type anorexia nervosa. Participants undergo neurophysiological (EEG), physiological (GSR), and attentional (eye-tracking) assessments before and after the intervention.

Study Record Dates

• First Submitted: June 17, 2025
• First Posted: June 25, 2025
• Study Start: May 15, 2025
• Primary Completion: September 15, 2025
• Study Completion: October 15, 2025
• Last Updated: June 25, 2025

Record last verified: 2025-06

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, CSR, ANALYTIC CODE
• Time Frame: IPD and supporting materials will be available beginning 6 months after publication of the primary results and will remain available for up to 5 years upon request.
• Access Criteria: Qualified researchers affiliated with academic institutions may request access to the IPD and supporting materials for ethically approved secondary analyses. Requests must include a brief research proposal and will be reviewed by the study investigators. Data will be shared via secure institutional transfer platforms upon data use agreement. Qualified researchers affiliated with academic institutions may request access to the IPD and supporting materials for ethically approved secondary analyses. Requests must include a brief research proposal and will be reviewed by the study investigators. Data will be shared via secure institutional transfer platforms upon data use agreement.

Locations

TU (1)