title: Effects of global atrophy, white matter lesions, and cerebral blood flow on age-related changes in speed, memory, intelligence, vocabulary, and frontal function.
abstract: Brain images were obtained from 133 healthy people of ages 61-85 years who completed 20 tests of information processing speed, intelligence, frontal and executive function, memory, and vocabulary. Structural equation models examined relationships between cognitive test scores, ages and measurements of global age-associated atrophy, white matter lesions, and cerebral blood flow. These neurophysiological measures jointly account for all age-related variance in information processing speed. Speed entirely mediated relationships between neurophysiological measures and memory and partly mediated relationships between neurophysiological measures and intelligence and frontal function. Neurophysiological measures, but not calendar age, accounted for vocabulary scores. Cognitive slowing was responsible for some, but not all, age-related declines in mental function. Age-related declines in intelligence, frontal function, and speed were due to changes in different functional systems.
authors.affiliation: Department of Experimental Psychology, University of Oxford, England. patrick.rabbitt@psy.ox.ac.uk
authors.forename: Patrick
authors.initials: P
authors.lastname: Rabbitt
authors.forename: Oemetse
authors.initials: O
authors.lastname: Mogapi
authors.forename: Marietta
authors.initials: M
authors.lastname: Scott
authors.forename: Neil
authors.initials: N
authors.lastname: Thacker
authors.forename: Christine
authors.initials: C
authors.lastname: Lowe
authors.forename: Mike
authors.initials: M
authors.lastname: Horan
authors.forename: Neil
authors.initials: N
authors.lastname: Pendleton
authors.forename: Alan
authors.initials: A
authors.lastname: Jackson
authors.forename: Dan
authors.initials: D
authors.lastname: Lunn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology* / Q000502:physiology*; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D002560:Cerebrovascular Circulation / Q000502:physiology; D005260:Female; D006801:Humans; D007360:Intelligence / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D008606:Mental Processes / Q000502:physiology*; D008875:Middle Aged; D008954:Models, Biological; D009483:Neuropsychological Tests / Q000706:statistics & numerical data