title: Brain characteristics of individuals resisting age-related cognitive decline over two decades.
abstract: Some elderly appear to resist age-related decline in cognitive functions, but the neural correlates of successful cognitive aging are not well known. Here, older human participants from a longitudinal study were classified as successful or average relative to the mean attrition-corrected cognitive development across 15-20 years in a population-based sample (n = 1561). Fifty-one successful elderly and 51 age-matched average elderly (mean age: 68.8 years) underwent functional magnetic resonance imaging while performing an episodic memory face-name paired-associates task. Successful older participants had higher BOLD signal during encoding than average participants, notably in the bilateral PFC and the left hippocampus (HC). The HC activation of the average, but not the successful, older group was lower than that of a young reference group (n = 45, mean age: 35.3 years). HC activation was correlated with task performance, thus likely contributing to the superior memory performance of successful older participants. The frontal BOLD response pattern might reflect individual differences present from young age. Additional analyses confirmed that both the initial cognitive level and the slope of cognitive change across the longitudinal measurement period contributed to the observed group differences in BOLD signal. Further, the differences between the older groups could not be accounted for by differences in brain structure. The current results suggest that one mechanism behind successful cognitive aging might be preservation of HC function combined with a high frontal responsivity. These findings highlight sources for heterogeneity in cognitive aging and may hold useful information for cognitive intervention studies.
authors.affiliation: Department of Psychology, Stockholm University, 10691 Stockholm, Sweden, Aging Research Center, Karolinska Institute, 11330 Stockholm, Sweden. sara.pudas@psychology.su.se
authors.forename: Sara
authors.initials: S
authors.lastname: Pudas
authors.forename: Jonas
authors.initials: J
authors.lastname: Persson
authors.forename: Maria
authors.initials: M
authors.lastname: Josefsson
authors.forename: Xavier
authors.initials: X
authors.lastname: de Luna
authors.forename: Lars-Göran
authors.initials: LG
authors.lastname: Nilsson
authors.forename: Lars
authors.initials: L
authors.lastname: Nyberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000473:pathology*; D001931:Brain Mapping; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000473:pathology*; D018672:Community Health Planning; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology
chemical_list: D010100:Oxygen