Motivating Factors That Play a Role in Bulimia Nervosa
Condition: Bulimia Nervosa; Eating Disorders
MeSH terms: Bulimia; Feeding and Eating Disorders; Bulimia Nervosa
Study type: Observational

Summary: 
      This study will evaluate whether people with bulimia nervosa will binge eat in a structured
      laboratory setting and display behavioral patterns similar to those of individuals who are
      dependent on drugs.
    

Detailed description: 
      Bulimia nervosa (BN) is a serious eating disorder that is characterized by frequent
      uncontrolled eating binges. These binges are often followed by compensatory behavior,
      including the following: self-induced vomiting; misuse of laxatives, diuretics, enemas, or
      other medications to induce purging; fasting; or excessive exercise. If left untreated, BN
      can lead to many serious health issues: tooth decay; irregular menstruation; bowel damage;
      constipation; heart and kidney disease; intestinal damage; puffiness, especially in the face
      and fingers; increased hair growth on the face and body; and mineral imbalances in the body.
      Similar to drug abuse disorders, food-related thinking and disordered eating behavior can
      interfere with other occupational and social activities, as well. This study will evaluate
      whether people with bulimia nervosa will binge eat in a structured laboratory setting and
      display behavioral patterns similar to those of individuals who are dependent on drugs.

      Interested participants will first report to the study site for a screening visit, during
      which they will be assessed for eligibility using blood tests and an interview. Eligible
      participants will return to the study site on 3 additional days. Participants will be asked
      to refrain from eating or drinking between 10 P.M. each night before reporting to the study
      site and 10 A.M. the next day. Each day, participants will receive breakfast, after which
      they will not be allowed to eat or drink until the end of the day. Participants will then use
      a computer program to earn food (a yogurt shake) by tapping on the keyboard. More taps on the
      keyboard will result in a larger amount of food earned by the end of the day. Once
      experimentation is complete on Day 1, participants will be instructed to eat as much as they
      can. On Days 2 and 3, participants will be given a small serving of the yogurt shake prior to
      beginning the computer task. Following the computer task, they will be instructed to either
      eat until they are comfortable (without restricting or binging), or eat as much as they can.
      A private bathroom will be available if needed. All participants, including those who did not
      meet criteria for participation, will be offered treatment at the study clinic once the study
      is complete.
    

Intervention name(s): Motivation to eat
Intervention type(s): Behavioral
Intervention description(s): Participants will use a computer program to earn food (a yogurt shake) by tapping on the keyboard. More taps on the keyboard will result in a larger amount of food earned by the end of the day. Once experimentation is complete on Day 1, participants will be instructed to eat as much as they can. On Days 2 and 3, participants will be given a small serving of the yogurt shake prior to beginning the computer task. Following the computer task, they will be instructed to either eat until they are comfortable (without restricting or binging), or eat as much as they can.
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Participants who meet DSM-IV criteria for bulimia nervosa and control participants who
        weigh between 80 and 120% of ideal weight