title: Cognition is only minimally impaired in Spinocerebellar ataxia type 14 (SCA14): a neuropsychological study of ten Norwegian subjects compared to intrafamilial controls and population norm.
abstract: BACKGROUND
  There is an increasing awareness of the role of the cerebellum not only in motor, but also in cognitive and emotional functions. Spinocerebellar ataxia type 14 (SCA14) is an autosomal dominant hereditary ataxia characterized by a relatively pure cerebellar phenotype. Cognitive impairment has been reported in studies with phenotype descriptions of SCA14, but previous studies have been small without control groups, and no homogeneous and systematic test panel has been used. The objective of this study was to thoroughly characterize the neuropsychological profile in ten Norwegian SCA14 subjects compared to unaffected family members and population norm data.
  
  
  METHODS
  Ten SCA14 subjects and ten intrafamilial unaffected age- and education-matched controls from two Norwegian families were included. The unaffected intrafamilial controls included six first degree relatives, two second degree relatives, and two spouses. General intellectual ability, memory, visuoperceptive skills, psychomotor speed, executive functions, depression and anxiety were examined using internationally standardized tests, with minimal need for manual response to avoid motor bias.
  
  
  RESULTS
  No significant cognitive deficit was found in SCA14 subjects compared to intrafamilial controls. Verbal IQ, verbal executive function and psychomotor speed tended to be reduced in affected subjects, but previously reported non-verbal executive dysfunction was not confirmed in this study.
  
  
  CONCLUSIONS
  Only subtle cognitive impairment was found in SCA14 affected subjects. The current findings do not confirm earlier reports of cognitive dysfunction in SCA14, but does shows a mild impairment in specific verbal executive functions. Genotypic differences may partly account for this discrepancy, and further studies on larger materials are needed to verify the findings.
authors.affiliation: Department of Neurology, Oslo University Hospital, Ullevål, Oslo, Norway. i.m.wedding@medisin.uio.no.
authors.forename: Iselin Marie
authors.initials: IM
authors.lastname: Wedding
authors.forename: Jeanette
authors.initials: J
authors.lastname: Koht
authors.forename: Espen
authors.initials: E
authors.lastname: Dietrichs
authors.forename: Nils Inge
authors.initials: NI
authors.lastname: Landrø
authors.forename: Chantal M E
authors.initials: CM
authors.lastname: Tallaksen
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D056344:Executive Function; D005192:Family Health; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D009664:Norway / Q000453:epidemiology; D011597:Psychomotor Performance; D012016:Reference Values; D012720:Severity of Illness Index; D020754:Spinocerebellar Ataxias; D013132:Spinocerebellar Degenerations / Q000150:complications*; D014796:Visual Perception; D055815:Young Adult