Dopamine Receptor Contributions to Prediction Error and Reversal Learning in Anorexia Nervosa

Early Phase 1

Completed

Conditions: Anorexia Nervosa

Interventions: Drug: amisulpride
Drug: bromocriptine
Drug: Placebo

Registration Number: NCT04128683

Lead Sponsor: University of California, San Diego

Brief Summary: Anorexia nervosa (AN) is an eating disorder associated with intense fear of weight gain, food refusal, and severe weight loss. AN has the highest mortality rate among the psychiatric disorders; however, little is known about biomarkers, and no medication has been approved for AN. Many individuals only partially recover, and treatment options, especially for the psychological components of the illness, are not very effective, highlighting the need for more effective treatments.

Brain reward pathways have a direct impact on the drive to eat, and a variety of neuroimaging studies have suggested altered reward processing in AN. The neurotransmitter dopamine has a central role in the reward circuitry to drive food approach, and the dynamic interplay between dopamine receptor response and food restriction could have implications for the pathophysiology of AN. Dopamine-related brain function has been studied indirectly using functional magnetic resonance brain imaging (fMRI) and tasks that deliver reward stimuli unexpectedly, that elicit the so-called prediction error (PE) response.

Research in AN showed repeatedly altered PE processing suggesting altered dopamine circuit function in the disorder.

Dopamine and PE response have also been associated with altered reversal learning, which has important treatment implication for AN as reversal learning is impaired in the disorder and modulation of the dopamine system could improve treatment.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: Female

Target Recruitment: 31

Inclusion Criteria

Healthy Controls

Females ages 18-29 years
Healthy body weight between 90 and 110 % average body weight since puberty.
Regular monthly menstrual cycle
Edinburgh Handedness Inventory Revised (EHI-R) LQ* score > +200
English is primary language spoken

Restricting Type Anorexia Nervosa

Females ages 18-29 years
Diagnostic criteria. Current diagnosis of AN, including being underweight below 17.5 body mass index (BMI, kg/m2), will have a severe fear of weight gain, body image distortion and absence of the menstrual cycle over three consecutive months.
First 1-2 weeks in treatment at The University of California San Diego Eating Disorders Center for Treatment and Research or Rady Children's Hospital San Diego Medical Behavioral Unit.
Restricting subtype, that is without binge/purge behaviors
Edinburgh Handedness Inventory Revised (EHI-R) LQ* score > +200
English is primary language spoken

Exclusion Criteria

Healthy Controls

Current pregnancy or breast feeding within last 3 months
Illiterate/Blind individuals
First degree relative with current or past eating disorder
Current Medications other than BCP or IUD
Contraindications to amisulpride or bromocriptine (as determined through medical history in bioscreen and PI interview) including: Syncopal migraine; Uncontrolled hypertension; Pheochromocytoma; Prolactinoma; Breast cancer; hypersensitivity/allergy to amisulpride or bromocriptine; History of long QT syndrome; Family history of sudden death or long QT syndrome; History of seizures or seizure disorder
Past or present Axis I psychiatric disorder including substance or alcohol use disorder as determined through SCID-5 clinical interview
Major Medical illness (as determined through medical history in bioscreen and PI interview) such as:

o Conditions that are life threatening: cancer heart disease stroke HIV/AIDS

o Conditions that are life threatening Conditions that cause serious disability without necessarily being life threatening: stroke closed head or spinal cord injuries mental retardation congenital malformations.

o Conditions that cause significant pain or discomfort that can cause serious interruptions to life activities: severe allergies migraine arthritis sickle cell disease

o Conditions that require major commitments of time and effort from care-givers for a substantial period of time: mobility disorders blindness Alzheimer's disease and other dementias chronic obstructive pulmonary disease paraplegia or quadriplegia Down's syndrome depression

o Conditions that may require frequent monitoring: diabetes conditions requiring anticoagulation treatment severe asthma severe allergies schizophrenia and other psychotic illnesses.

o Conditions that predict or are associated with severe consequences: hypertension (associated with heart disease) depression (associated with suicide) diabetes (associated with blindness, kidney failure) alcohol and other substance abuse (associated with intentional and unintentional injuries).
Recent history of suspected substance abuse or a lifetime history of psychostimulant abuse and/or dependence
Metal implants or braces (as determined through fMRI screening form)

Anorexia Nervosa

Pregnancy or breast feeding within last 3 months
Lifetime history of bipolar disorder or psychosis
Illiterate/Blind individuals
Contraindications to amisulpride or bromocriptine (as determined through medical history in bioscreen and PI interview) including: Syncopal migraine; Uncontrolled hypertension; Pheochromocytoma; Prolactinoma; Breast cancer; hypersensitivity/allergy to amisulpride or bromocriptine; History of long QT syndrome; Family history of sudden death or long QT syndrome; History of seizures or seizure disorder
Use of an anti-psychotic or other dopamine acting medication including stimulants within the past week at time of MRI
Recent history of substance abuse or dependence (within the last month)
Major Medical illness (as determined through medical history in bioscreen and PI interview) such as:

o Conditions that are life threatening: cancer heart disease stroke HIV/AIDS

o Conditions that are life threatening Conditions that cause serious disability without necessarily being life threatening: stroke closed head or spinal cord injuries mental retardation congenital malformations.

o Conditions that cause significant pain or discomfort that can cause serious interruptions to life activities: severe allergies migraine arthritis sickle cell disease

o Conditions that require major commitments of time and effort from care-givers for a substantial period of time: mobility disorders blindness Alzheimer's disease and other dementias chronic obstructive pulmonary disease paraplegia or quadriplegia Down's syndrome

o Conditions that may require frequent monitoring: diabetes conditions requiring anticoagulation treatment severe asthma severe allergies schizophrenia and other psychotic illnesses.

o Conditions that predict or are associated with severe consequences: hypertension (associated with heart disease) diabetes (associated with blindness, kidney failure) alcohol and other substance abuse (associated with intentional and unintentional injuries) within the last month
Metal implants or braces (as determined through fMRI screening form)

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Healthy Controls, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Healthy Controls, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	amisulpride	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	bromocriptine	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Healthy Controls, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	Placebo	Individuals in the healthy control group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Amisulpride; Scan3: Bromocriptine	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Placebo; Scan2: Bromocriptine; Scan3: Amisulpride;	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Placebo(single dose, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Placebo; Scan3: Bromocriptine	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Amisulpride; Scan2: Bromocriptine; Scan1: Placebo	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 2: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Placebo; Scan 3: Amisulpride	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Placebo(single dose, 3 hours pre-scan) Scan 3: Amisulpride (single dose, 400 mg, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	amisulpride	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	bromocriptine	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)
Anorexia Nervosa, Scan1: Bromocriptine; Scan2: Amisulpride; Scan3: Placebo	Placebo	Individuals in the anorexia nervosa group were randomized to the following scan order. Participants were administered a study medication or placebo 3 hours prior to the start of the scan. The participant did not know what study medication they received for each scan: Scan 1: Bromocriptine (single dose, 1.25 mg, 3 hours pre-scan) Scan 2: Amisulpride (single dose, 400 mg, 3 hours pre-scan) Scan 3: Placebo(single dose, 3 hours pre-scan)

Primary Outcome Measures

Name	Time	Method
Measurement of Brain Activation (Measured in Percent Signal Change) During a Prediction Error Taste Reward Task Using Functional Magnetic Resonance Imaging (fMRI).	The outcome measure was assessed during the taste MRI task on each of the 3 intervention scan days over the course of 9 to 12 days	This task measures responsiveness to unexpected stimulus in the dopamine related brain circuitry. Study participants in both the healthy control group and anorexia nervosa group completed 3 fMRI scans. Prior to each scan subjects were administered one of three study medications (amisulpride, bromocriptine, or placebo). During the fMRI scan, subjects completed a taste reward prediction error task where they viewed visual stimuli and then received one of three conditions: sweet taste, neutral taste, or no solution. 20 percent of stimulus receipt was unexpected, that is there is a mismatch between expectation and outcome. Using a region of interest (ROI)-based approach, brain activation percent signal change values were extracted from the brain images for each subject and compared across groups and medication scans. A repeated measures ANOVA was used to calculate the mean brain activation for each group and each medication scan.
Measurement of Brain Activation (Measured in Percent Signal Change) During Taste Stimulus Expectation Using Functional Magnetic Resonance Imaging (fMRI).	The outcome measure was assessed during the taste MRI task on each of the 3 intervention scan days over the course of 9 to 12 days	Study participants in both the healthy control group and anorexia nervosa group completed 3 fMRI scans. Prior to each scan subjects were administered one of three study medications (amisulpride, bromocriptine, or placebo). During the fMRI scan, subjects completed a taste reward prediction error task where they viewed visual stimuli and then received one of three conditions: sweet taste, neutral taste, or no solution. Using a region of interest (ROI)-based approach, brain activation percent signal change values were extracted from the brain images for each subject and compared across groups and medication scans. Here only stimulus expectation data were analyzed. A repeated measures ANOVA was used to calculate the mean brain activation for each group and each medication scan.

Secondary Outcome Measures