Neural Correlates of Reward and Symptom Expression in Anorexia Nervosa

Neural Correlates of Reward and Symptom Expression in Anorexia Nervosa

The objective of this study is to identify the patterns of brain activity in reward circuitry that promote symptoms of anorexia nervosa. This project will compare weight-restored individuals with anorexia nervosa to a non-eating disorder control group on reward brain circuitry patterns in response to typically rewarding cues (i.e., entertaining videos) and disorder-specific restrictive eating cues (i.e., low-fat food choice) using fMRI. In addition, this study will examine which neurobiological reward responses among weight-restored individuals with anorexia nervosa predict objective restrictive eating (measured by laboratory meal intake) and longitudinal risk of relapse one year later.

Aim 1: To compare patterns of brain activity in reward circuits to typically rewarding cues and disorder-specific cues between weight-restored individuals with anorexia nervosa and non-eating disorder controls

Hypothesis 1a: Activity in reward circuitry will be elevated in response to typically rewarding cues in the non-eating disorder control group versus weight-restored anorexia nervosa group.

Hypothesis 1b: Activity in reward circuitry will be elevated in response to disorder-specific in the weight-restored anorexia nervosa group versus the non-eating disorder control group.

Aim 2: To specify the relationship between brain patterns related to reward and restrictive eating among weight-restored individuals with anorexia nervosa

Hypothesis 2a: Lower reward circuit activity in response to typically rewarding cues will predict lower test meal intake for weight-restored anorexia nervosa group versus the non-eating disorder control group.

Hypothesis 2b: Higher reward circuit activity in response to disorder-specific cues will predict lower test meal intake for the weight-restored anorexia nervosa group versus the non-eating disorder control group.

Aim 3: To identify the brain patterns in reward circuitry associated with the risk of relapse among weight-restored individuals with anorexia nervosa in the year following weight-restoration.

Hypothesis 3a: Lower reward circuit activity in response to typically rewarding cues will predict relapse in the weight-restored anorexia nervosa group.

Hypothesis 3b: Higher reward circuit activity in response to disorder-specific cues will predict relapse in the weight-restored anorexia nervosa group.

Inclusion Criteria:

• Age > 18 years old
• Current BMI > 18.5 kg/m2
• Ability to read and speak in English
• Right-handed
• Weight restored Anorexia Nervosa group: 1) DSM-5 diagnosis of AN in the past 6 months, with the exception of body image disturbance and intense fear of weight gain criteria; 2) BMI < 18.5 kg/m2 within past 6 months

Exclusion Criteria:

• Medical instability or current pregnancy
• Current substance use disorder, psychosis, or bipolar-I disorder
• Contraindication for fMRI
• History of neurological disorder/injury (e.g., stroke; head injury with > 10 minutes loss of consciousness)
• Food allergy that cannot be accommodated through substitutions to the laboratory test meal
• Lacking capacity to consent
• Non-eating disorder Control group: Current DSM-5 Axis-I diagnosis or current or past eating disorder diagnosis