title: Perseveration in Alzheimer's disease.
abstract: OBJECTIVE
  Perseveration is common in Alzheimer's disease (AD). We document the type and quantitative burden of perseveration as cognitive decline progresses from normal aging (n = 30) through mild AD (n = 20) to moderate AD (n = 20) by administering a semantic verbal fluency task.
  
  
  RESULTS
  We found perseveration to increase significantly with increasing severity of AD and different types of perseveration that distinguish the subject groups in a statistically significant manner. Recurrent and continuous perseverations appear early in AD. As the disease progresses in severity into moderate stage, the number of recurrent and continuous perseverations increases, and stuck-in-set perseverations emerge.
  
  
  CONCLUSIONS
  The different types of perseveration are likely to reflect the progressive deterioration of different brain regions in AD.
authors: Department of Speech Sciences, University of Helsinki, Helsinki, Finland. seija.pekkala@helsinki.fi
authors: S
authors: S
authors: Pekkala
authors: M L
authors: ML
authors: Albert
authors: A
authors: A
authors: Spiro
authors: T
authors: T
authors: Erkinjuntti
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D000544:Alzheimer Disease / Q000453:epidemiology*; D001921:Brain / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012660:Semantics; D012720:Severity of Illness Index; D014705:Verbal Behavior