Neurophysiological Effects of Cognitive-Behavioral Therapy in Anorexia Nervosa: A Pre-Post EEG, GSR, and Eye-Tracking Study
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Change in EEG P300 amplitude in response to body image stimuli
研究概览
简要总结
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.
详细描述
Anorexia nervosa (AN) is a severe psychiatric disorder characterized by distorted body image, food restriction, and intense fear of weight gain. Despite the effectiveness of Cognitive-Behavioral Therapy (CBT) in targeting maladaptive cognitions and behaviors, its underlying neurophysiological mechanisms remain insufficiently understood. This study aims to evaluate the effects of a 12-week CBT intervention on neural, physiological, and attentional responses in individuals with restrictive-type AN using a randomized controlled trial design.
Sixty female participants (aged 18-35) with restrictive-type AN will be recruited and randomly assigned to one of two groups: a CBT intervention group (n = 30) and a waitlist control group (n = 30). Both groups will undergo baseline and post-intervention assessments using EEG, GSR, and eye-tracking. The CBT intervention will consist of weekly 60-minute sessions for 12 weeks, delivered by trained therapists, and will target body image distortion, cognitive restructuring, exposure to food-related stimuli, emotional regulation, and avoidance behaviors.
During the experimental task, participants will view a series of visual stimuli including (1) self-images (unaltered, altered-thin, altered-overweight), (2) food images (low- vs. high-calorie), and (3) images of other female bodies (thin vs. normal weight). EEG markers of interest include P300 (attentional salience), Late Positive Potential (LPP; sustained emotional reactivity), and frontal alpha asymmetry (indicative of affect regulation and self-referential processing). It is hypothesized that CBT will lead to reductions in P300 and LPP amplitudes and an increase in left-frontal cortical activity, indicating enhanced emotional control and reduced fixation on thin-ideal stimuli.
GSR will be used to assess physiological arousal in response to distressing stimuli. It is expected that post-CBT participants will exhibit lower skin conductance responses (SCRs) to body and food images, indicating improved autonomic regulation. Eye-tracking data will capture fixation durations and gaze patterns. Participants in the CBT group are expected to show less visual attention toward "problematic" body areas (waist, stomach, thighs) and reduced avoidance of high-calorie food images compared to the waitlist group.
Participants will also complete standardized psychometric instruments including the Eating Disorder Examination Questionnaire (EDE-Q), Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI), the Yale-Brown Obsessive-Compulsive Scale for Body Dysmorphic Disorder (YBOCS-BDD), and the Cognitive Emotion Regulation Questionnaire (CERQ) at both time points.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 35 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •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
排除标准
- •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
研究组 & 干预措施
CBT Intervention Group
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.
干预措施: Cognitive-Behavioral Therapy (Behavioral)
Waitlist Control Group
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.
结局指标
主要结局
Change in EEG P300 amplitude in response to body image stimuli
时间窗: aseline and Week 12
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.
Change in Late Positive Potential (LPP) amplitude to body and food stimuli
时间窗: Baseline and Week 12
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.
Change in frontal alpha asymmetry during self-image viewing
时间窗: Baseline and Week 12
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.
Change in skin conductance response (SCR) to body and food stimuli
时间窗: Baseline and Week 12
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.
Change in fixation duration on weight-related body areas
时间窗: Baseline and Week 12 Baseline and Week 12
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.
次要结局
- 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)
- Change in subjective distress ratings on Visual Analog Scale (VAS)(Immediately after the experimental task at both baseline and Week 12)
研究者
Metin Çınaroğlu
Assistant Professor
Istanbul Nisantasi University