title: Cognitive reserve: a SPECT study of 132 Alzheimer's disease patients with an education range of 0-19 years.
abstract: This study examines the associations between education, cerebral perfusion, and cognitive test performance among 132 patients with Alzheimer's disease. The participants had had between 0 and 19 years of formal schooling, and had either mild or moderate dementia according to the Clinical Dementia Rating Scale. Cerebral perfusion was evaluated by the (99m)Tc-hexamethylpropylene amine oxime single photon emission computed tomography. The Mini-Mental State Examination and the Cognitive Abilities Screening Instrument were used to assess cognitive performance. For patients at each clinical dementia severity level, statistical parametric mapping was used to examine voxel by voxel the association between education and cerebral perfusion, and Pearson's correlation coefficients were calculated between education and cognitive test scores. Years of formal schooling had negative associations with cerebral perfusion and positive associations with cognitive test scores. The brain regions showing a significant education effect on perfusion involved bilateral posterior association areas in mild dementia, and bilateral parieto-temporo-frontal areas in moderate dementia. The present findings indicate that the cognitive reserve effect starts at the low end of the education range. They also suggest that the main effect of more education is a more facile use of alternative brain circuits instead of locally increased synaptic connections.
authors.affiliation: Department of Neurology, National Yang-Ming University School of Medicine and Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Yi-Chu
authors.initials: YC
authors.lastname: Liao
authors.forename: Ren-Shyan
authors.initials: RS
authors.lastname: Liu
authors.forename: Evenly Lee
authors.initials: EL
authors.lastname: Teng
authors.forename: Yi-Chung
authors.initials: YC
authors.lastname: Lee
authors.forename: Pei-Ning
authors.initials: PN
authors.lastname: Wang
authors.forename: Ker-Neng
authors.initials: KN
authors.lastname: Lin
authors.forename: Chih-Ping
authors.initials: CP
authors.lastname: Chung
authors.forename: Hsiu-Chih
authors.initials: HC
authors.lastname: Liu
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000473:pathology; D002560:Cerebrovascular Circulation / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology; D004522:Educational Status; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed