title: Subtle imitation behaviour in convenience samples of normal, demented, and currently depressed elderly subjects.
abstract: BACKGROUND
  The clinical significance of imitation behaviour (IB) is unclear. The aim of this study was to investigate the prevalence of subtle naïve and obstinate IB in convenience samples of normal elderly, demented, and depressed subjects.
  
  
  METHODS
  Subtle IB was assessed using a protocol constructed ad hoc in 146 patients, consecutively referred to a memory clinic having received an ICD-10 diagnosis of either dementia or depression, and in 241 healthy subjects. The prevalence of IB in the three groups was determined and the association with possible demographic, cognitive, and non-cognitive variables analysed.
  
  
  RESULTS
  Subtle naïve IB was frequent in the elderly with dementia, intermediate in the depressed, and rare in the normal elderly except that the latter frequently stretched out their arms. Obstinate IB never occurred in the normal elderly. IB was predicted by none of the variables used.
  
  
  CONCLUSIONS
  The groups included were convenience samples with the depressed being a small group precluding further distinction of depressive subtypes.
  
  
  CONCLUSIONS
  Although naïve IB is a frequent clinical feature in the demented, it also accompanies depressive disorders in the elderly. It can be observed as context-specific IB in the normal elderly. Obstinate IB does not occur in the normal elderly.
authors.affiliation: Service of Old Age Psychiatry of the Department of Psychiatry - CHUV, Lausanne, Switzerland. armin.von-gunten@chuv.ch
authors.forename: Armin
authors.initials: A
authors.lastname: von Gunten
authors.forename: René
authors.initials: R
authors.lastname: Duc
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003704:Dementia / Q000175:diagnosis / Q000523:psychology*; D015140:Dementia, Vascular / Q000175:diagnosis / Q000523:psychology*; D003866:Depressive Disorder / Q000175:diagnosis / Q000523:psychology*; D005260:Female; D006801:Humans; D007100:Imitative Behavior; D020961:Lewy Body Disease / Q000175:diagnosis / Q000523:psychology*; D008297:Male; D008609:Mental Status Schedule; D009483:Neuropsychological Tests; D012016:Reference Values; D013223:Statistics as Topic