title: A structural MRI study of motor conversion disorder: evidence of reduction in thalamic volume.
abstract: OBJECTIVE
  To investigate potential abnormalities in subcortical brain structures in conversion disorder (CD) compared with controls using a region of interest (ROI) approach.
  
  
  METHODS
  Fourteen patients with motor CD were compared with 31 healthy controls using high-resolution MRI scans with an ROI approach focusing on the basal ganglia, thalamus and amygdala. Brain volumes were measured using Freesurfer, a validated segmentation algorithm.
  
  
  RESULTS
  Significantly smaller left thalamic volumes were found in patients compared with controls when corrected for intracranial volume. These reductions did not vary with handedness, laterality, duration or severity of symptoms.
  
  
  CONCLUSIONS
  These differences may reflect a primary disease process in this area or be secondary effects of the disorder, for example, resulting from limb disuse. Larger, longitudinal structural imaging studies will be required to confirm the findings and explore whether they are primary or secondary to CD.
authors.affiliation: Section of Cognitive Neuropsychiatry, Institute of Psychiatry, King's College London, , London, UK.
authors.forename: T R
authors.initials: TR
authors.lastname: Nicholson
authors.forename: S
authors.initials: S
authors.lastname: Aybek
authors.forename: M J
authors.initials: MJ
authors.lastname: Kempton
authors.forename: E M
authors.initials: EM
authors.lastname: Daly
authors.forename: D G
authors.initials: DG
authors.lastname: Murphy
authors.forename: A S
authors.initials: AS
authors.lastname: David
authors.forename: R A
authors.initials: RA
authors.lastname: Kanaan
mesh_terms: D000328:Adult; D000679:Amygdala / Q000473:pathology; D001284:Atrophy / Q000473:pathology; D001479:Basal Ganglia / Q000473:pathology; D016022:Case-Control Studies; D003291:Conversion Disorder / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D059906:Neuroimaging; D013788:Thalamus / Q000473:pathology*
keywords: HYSTERIA; IMAGE ANALYSIS; MRI; NEUROANATOMY; NEUROPSYCHIATRY