Functional Magnetic Resonance Imaging (fMRI) Imaging Study in Adolescents With Anorexia Nervosa
Condition: Anorexia Nervosa
MeSH terms: Anorexia; Anorexia Nervosa
Study type: Observational

Summary: 
      The purpose of this study is to use fMRI imaging technology to examine areas in the brain
      related to appetite, reward and cognition in adolescent women with eating disorders as
      compared to those who have never had an eating disorder. Better understanding biologic
      vulnerabilities in women with anorexia is essential for developing more effective treatment
      options.
    

Detailed description: 
      Individuals with anorexia nervosa (AN) have aberrant feeding behavior, disturbances of
      emotionality and impulse control, and have high rates of relapse after weight restoration
      (Carter et al., 2004; Halmi et al., 2003). There is no proven treatment that reverses
      symptoms. Although imaging studies in individuals recovered from AN (REC AN) suggest that
      these symptoms are related to dysfunction of the striatal, insular, and prefrontal areas,
      less is known about the biology of these core symptoms in currently ill individuals (ILL AN).
      This application will use blood oxygen level-dependent (BOLD) functional magnetic resonance
      imaging (fMRI) to examine neural substrates underlying appetitive, reward, and cognitive
      dysregulation in ill AN. We will study 22 adolescent women currently ill with AN and 22
      healthy adolescent control women (CW), all of whom are 14 to 18 years old.

      The specific aims of the project are:

      AIM 1: The anterior insula (AI), orbitofrontal cortex (OFC), and associated regions integrate
      sensory/hedonic aspects of taste and interoceptive awareness in the service of homeostasis.
      We hypothesize that restricted eating and weight loss occur in AN because a palatable food
      elicits little reward.

      AIM 2: Little in life is rewarding to individuals with AN aside from weight loss, and they
      tend to be overconcerned with future consequences. We predict that ill AN will show an
      inability to discriminate positive and negative feedback reflecting aberrant anterior ventral
      striatum (AVS) limbic function.

      AIM 3: AN tend to be rigid, inflexible and behaviorally inhibited. We will use a stop task
      (Band et al., 2003; Logan et al., 1984; Matthews et al., 2005) to characterize the neural
      substrates of inhibitory motor control. We hypothesize that ill AN, relative to CW, will show
      a demand-specific alteration of a fronto-subthalamic circuit that is necessary for motor
      inhibition (Aron et al., 2004).

      AIM 4: In an exploratory aim, we propose to examine how clinical, cognitive, and
      personality/temperament measures might be correlated to either the BOLD response and/or the
      integrity of frontostriatal connectivity as determined using diffusion tensor imaging (DTI).

      Taken together, these aims will enable us to better characterize cognitive and limbic
      dysfunction in these populations. Understanding biologic vulnerabilities in AN is critical
      for developing effective treatment interventions for this often chronic and deadly disorder.
      In addition, there is a lack of understanding of appropriate methodologies necessary to
      address the unique problems inherent in the study of ill AN. Thus, this project will also
      characterize confounding factors, such as brain volume, energy metabolism, development
      stages, and gonadal steroids, with the intent that a future project will incorporate the
      methodology needed to rigorously investigate this population.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Participants with anorexia nervosa will be selected from the community as well as from
        local medical clinics and eating disorder treatment centers. Healthy volunteers will be
        selected from the community at large.