title: Insular dysfunction and descending pain inhibition in anorexia nervosa.
abstract: OBJECTIVE
  Reduced perception of pain is a well-established phenomenon in patients with anorexia nervosa (AN). We tested the hypothesis that altered processing of pain within the insula might account for reduced perception of pain.
  
  
  METHODS
  Heat pain thresholds were obtained in nineteen patients with AN and matched controls. Thereafter, a thermode was used to deliver thermal painful stimuli to the right arm during functional magnetic resonance imaging (fMRI) measurements. Stimuli were initiated for 10 s from a baseline resting temperature (32°C) to three different levels (37, 42, 45°C).
  
  
  RESULTS
  Significantly increased heat pain thresholds were observed in patients. A stronger activation during heat pain perception was found in the left posterior insula in controls. In contrast, higher levels of activity were shown in the ipsilateral pons in patients when compared to controls. In patients, we found a significant interrelation between the depression score (Beck depression inventory) and heat pain activations.
  
  
  CONCLUSIONS
  We suggest that reduced activity in the left posterior insula might contribute to increased pain thresholds in patients, while increased activations in the right anterior insula and pons mirror augmented sympathetic modulation putatively related to amplification of adrenergic descending pain inhibition. In addition, pain thresholds and brain activations were influenced by disease-inherent depressed mood.
authors: Pain & Autonomics - Integrative Research (PAIR), Department of Psychiatry and Psychotherapy, University Hospital Jena, Jena, Germany. karl-juergen.baer@med.uni-jena.de
authors: K-J
authors: KJ
authors: Bär
authors: S
authors: S
authors: Berger
authors: C
authors: C
authors: Schwier
authors: U
authors: U
authors: Wutzler
authors: F
authors: F
authors: Beissner
mesh_terms: D000293:Adolescent; D000328:Adult; D000856:Anorexia Nervosa / Q000150:complications / Q000503:physiopathology*; D001921:Brain / Q000503:physiopathology; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D005260:Female; D059907:Functional Neuroimaging; D006358:Hot Temperature; D006801:Humans; D006987:Hypesthesia / Q000150:complications / Q000503:physiopathology*; D007091:Image Processing, Computer-Assisted; D007266:Inhibition, Psychological; D008279:Magnetic Resonance Imaging; D008297:Male; D058748:Pain Perception / Q000502:physiology*; D017288:Pain Threshold; D055815:Young Adult