title: Prolonged P3 latency and decreased brain perfusion in cerebellar degeneration.
abstract: OBJECTIVE
  To clarify the underlying mechanism of cognitive impairments in patients with cerebellar degeneration using event-related potentials (ERPs) and regional brain perfusion measurement.
  
  
  METHODS
  The P3 latency of ERPs was measured during a visual discrimination task in 15 patients with idiopathic late-onset cerebellar ataxia (ILOCA) and 10 age-matched control subjects. Regional brain perfusion was measured by single photon emission computed tomography using N-isopropyl-p[123I] iodoamphetamine.
  
  
  RESULTS
  The mean P3 latency was longer in the patients than in controls. The patients showed lower perfusion in the frontal cortex and in the cerebellum than control subjects. There was a significant correlation between perfusion of the frontal cortex and cerebellum.
  
  
  CONCLUSIONS
  The results indicate that patients with ILOCA exhibit slowing of cognitive information processing and suggest that its cognitive slowing may be due to a disruption of neural circuits between the cerebellum and the frontal cortex.
authors.affiliation: The Fifth Department of Internal Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tachibana
authors.forename: K
authors.initials: K
authors.lastname: Kawabata
authors.forename: Y
authors.initials: Y
authors.lastname: Tomino
authors.forename: M
authors.initials: M
authors.lastname: Sugita
mesh_terms: D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging; D002524:Cerebellar Ataxia / Q000503:physiopathology*; D003072:Cognition Disorders / Q000209:etiology* / Q000503:physiopathology; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D020367:Iofetamine; D008297:Male; D008606:Mental Processes; D008875:Middle Aged; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed; D014796:Visual Perception
chemical_list: D019275:Radiopharmaceuticals; D020367:Iofetamine