Functional Magnetic Resonance Imaging (fMRI) Investigation Into Compulsivity in Anorexia
Condition: Anorexia Nervosa in Remission (Disorder); Compulsive Behavior
MeSH terms: Anorexia; Anorexia Nervosa; Compulsive Behavior
Study type: Interventional

Summary: 
      The investigators will examine compulsivity in those who have recovered from anorexia
      nervosa, using a multi-modal MRI study. The neural activation of key fronto-striatal areas
      will be explored using a task which examines set-shifting and reversal-learning, two key
      components of compulsivity. Additionally, the functional networks displayed during
      resting-state MRI will be examined between groups, as will the neurochemicals present (using
      Magnetic Resonance spectroscopy).
    

Detailed description: 
      The investigators will perform four different MRI (Magnetic Resonance Imaging) scans during
      one scanning session on those who have recovered from anorexia nervosa (AN) and healthy
      controls.

      Participants will come to the Warneford hospital for a 2.5 hour screening visit, which will
      consist of questionnaires and interviews to determine their medical and psychiatric history
      and current mood, along with a practice of the task they'll do in the scanner. Participants
      will also complete two tasks which measure compulsivity and can be correlated with their
      brain activity in the scans. The investigators will also go through a scanning safety form
      with participants at this time.

      Participants will also attend a scanning visit, which will last 1.5 hours. One of the scans
      will look at how the brain responds to a particular task. This task will examine aspects of
      compulsivity (which is rigidly repeating actions that aren't rewarding) by using face and
      house stimuli (see reference 1).

      The investigators will also perform a scan when participants are at rest, in order to see if
      there are differences in the way areas of the brain connect to each other who used to have
      AN. The scientific literature indicates that there may be differences in the some key brain
      networks, including one which is thought to be involved in reflection and the self (the
      default mode network), which might also be linked to compulsivity (see reference 2).

      This study will also further investigate some initial pilot findings using Magnetic Resonance
      Spectroscopy, which allows researchers to examine the levels of different neurochemicals in
      the brain. It has been found that those with a current diagnosis of AN have lower levels of
      glutamate (a key brain chemical) compared to healthy controls, which is a finding we seek to
      extend in those who have recovered from AN (see reference 3).

      Aims: The investigators aim to see whether there are differences in the brains of those who
      have recovered from anorexia compared to those who have never had an anorexia diagnosis. This
      will be both at rest, and whilst participants are doing a task which measures compulsivity,
      as compulsivity is thought to be a particular risk factor for eating disorders.

      Value: If the investigators are able to identify differences, these might reflect underlying
      risk factors for eating disorders, which could lead to potential future treatments or
      prevention schemes.
    

Intervention name(s): MRI
Intervention type(s): Other
Intervention description(s): MRI scan, including structural imaging, functional imaging (both task-related and structural), and Magnetic Resonance Spectroscopy.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Intervention model description: All participants undero go an MRI scan, complete some questionnaires and two computer tasks. Participants are in two groups: those who have recovered from anorexia nervosa, and healthy control participants.
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: MRI