title: Trail making test part a and brain perfusion imaging in mild Alzheimer's disease.
abstract: OBJECTIVE
  The Trail Making Test (TMT) has long been used to investigate deficits in cognitive processing speed and executive function in humans. However, there are few studies that elucidate the neural substrates of the TMT. The aim of the present study was to identify the regional perfusion patterns of the brain associated with performance on the TMT part A (TMT-A) in patients with Alzheimer's disease (AD).
  
  
  METHODS
  Eighteen AD patients with poor performance on the TMT-A and 36 age- and sex-matched AD patients with good performance were selected. All subjects underwent brain single photon emission computed tomography.
  
  
  RESULTS
  No significant differences between the good and poor performance groups were found with respect to years of education and revised Addenbrooke's Cognitive Examination scores. However, higher z-scores for hypoperfusion in the bilateral superior parietal lobule were observed in the group that scored poorly on the TMT-A compared with the good performance group.
  
  
  CONCLUSIONS
  Our results suggest that functional activity of the bilateral superior parietal lobules is closely related to performance time on the TMT-A. Thus, the performance time on the TMT-A might be a promising index of dysfunction of the superior parietal area among mild AD patients.
authors.affiliation: Department of Neuropsychiatry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Shindo
authors.forename: Seishi
authors.initials: S
authors.lastname: Terada
authors.forename: Shuhei
authors.initials: S
authors.lastname: Sato
authors.forename: Chikako
authors.initials: C
authors.lastname: Ikeda
authors.forename: Shigeto
authors.initials: S
authors.lastname: Nagao
authors.forename: Etsuko
authors.initials: E
authors.lastname: Oshima
authors.forename: Osamu
authors.initials: O
authors.lastname: Yokota
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Uchitomi
keywords: Alzheimer's disease; Cerebral blood flow; Single photon emission computed tomography; Trail Making Test