Age-related reorganization of encoding networks directly influences subsequent recognition memory.
Functional magnetic resonance imaging was used to link performance-related brain activity during two word encoding tasks to subsequent recognition for those words in young and older adults. There were no significant group differences in performance during encoding, but the young subjects performed better than the older at the recognition task. Performance-related brain networks strongly differed between the two groups. In young subjects, there were two networks associated with performance, one related to encoding (mainly involving premotor and parietal brain regions) and the other to recognition (involving middle frontal, and lateral and medial temporal regions), whereas the network for older subjects (including prefrontal, premotor, lateral and medial temporal regions) was associated both with encoding and recognition. Areas in this network strongly overlapped with those supporting recognition in the young subjects (e.g., medial temporal lobe), suggesting that older subjects may have recruited these areas to maintain performance during encoding. However, this reorganization of brain networks appears to have come at the cost of subsequent recognition.
Tisserand
Danielle J
DJ
Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Ontario, Canada M6A 2E1. dtisserand@rotman-baycrest.on.ca
McIntosh
Anthony R
AR
van der Veen
Freddy M
FM
Backes
Walter H
WH
Jolles
Jelle
J
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D009415:Nerve Net / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology*; D021641:Recognition, Psychology / Q000502:physiology*
D010100:Oxygen