title: Neural Correlates of Stroop Performance in Alzheimer's Disease: A FDG-PET Study.
abstract: OBJECTIVE
  The Stroop test is commonly applied in elderly subjects for the evaluation of cognitive impairment related to Alzheimer's disease (AD) and related disorders. This study aimed to investigate the functional neural correlates of the Stroop performance in AD.
  
  
  METHODS
  In 136 probable AD patients and 54 cognitively normal elderly, a [(18)F]-fluorodeoxyglucose positron emission tomography scan and Stroop Color Word Test (SCWT) were performed. The correlations between the Stroop effect, which was measured by 6 different scoring methods, and regional cerebral glucose metabolism (rCMglc) were explored using a region-of-interest (ROI) approach and voxel-based analysis.
  
  
  RESULTS
  Among 6 Stroop interference measures, only 2 scores, including the SCWT color-word (CW) score, were significantly correlated with rCMglc of the dorsolateral prefrontal and anterior cingulate ROIs. Voxel-based analysis revealed significant positive correlations between SCWT CW scores and rCMglc in the inferior parietal lobule, middle temporal gyrus and middle frontal gyrus. Such correlations remained significant only in the less severe AD group.
  
  
  CONCLUSIONS
  In AD patients, the Stroop effect depends on the functional integrity of the prefrontal cortices. Some parietotemporal regions also appear to be responsible for the Stroop effect in AD individuals.
authors.affiliation: Department of Neuropsychiatry, Seoul National University Hospital, Bucheon, Korea.
authors.forename: Je-Yeon
authors.initials: JY
authors.lastname: Yun
authors.forename: Dong Young
authors.initials: DY
authors.lastname: Lee
authors.forename: Eun Hyun
authors.initials: EH
authors.lastname: Seo
authors.forename: Il Han
authors.initials: IH
authors.lastname: Choo
authors.forename: Shin Young
authors.initials: SY
authors.lastname: Park
authors.forename: Shin Gyeom
authors.initials: SG
authors.lastname: Kim
authors.forename: Jong In
authors.initials: JI
authors.lastname: Woo