Cerebral Amyloid Deposition and Dual-Tasking in Cognitively Normal, Mobility Unimpaired Older Adults.
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ABSTRACT: Background
We examined relationships between cerebral amyloid-beta (A?) and cognitive-gait dual-task performance in 27 cognitively normal, mobility unimpaired elders.Methods
We assessed A? on Pittsburgh Compound B (PiB)-PET. We measured gait speed separately and while performing working-memory, response-inhibition, motor-sequencing, and phone-dialing tasks. We compared dual-task costs on gait and cognitive performance in high-A? (PiB(+)) and low-A? (PiB(-)) groups and examined the association between A? and dual-task performance decrements.Results
PiB(+) (n = 16) were comparable with the PiB(-) (n = 11) individuals on demographics, general cognitive and physical performance, and key brain MRI characteristics. PiB(+) group demonstrated greater dual-task costs on gait speed on all cognitive tasks (p < .05) except on response inhibition. Dual-task costs on cognition were similar between groups. Overall, A? was associated with dual-task decrement on gait speed but not on dual-task decrement on cognitive performance.Conclusions
Preliminary evidence indicates that cerebral A? is associated with gait slowing on dual-tasking in healthy older adults.
SUBMITTER: Nadkarni NK
PROVIDER: S-EPMC5968634 | biostudies-literature | 2017 Mar
REPOSITORIES: biostudies-literature
Publications
Cerebral Amyloid Deposition and Dual-Tasking in Cognitively Normal, Mobility Unimpaired Older Adults.
Nadkarni Neelesh K NK Lopez Oscar L OL Perera Subashan S Studenski Stephanie A SA Snitz Beth E BE Erickson Kirk I KI Mathis Chester A CA Nebes Robert D RD Redfern Mark M Klunk William E WE
The journals of gerontology. Series A, Biological sciences and medical sciences 20170301 3
<h4>Background</h4>We examined relationships between cerebral amyloid-beta (Aβ) and cognitive-gait dual-task performance in 27 cognitively normal, mobility unimpaired elders.<h4>Methods</h4>We assessed Aβ on Pittsburgh Compound B (PiB)-PET. We measured gait speed separately and while performing working-memory, response-inhibition, motor-sequencing, and phone-dialing tasks. We compared dual-task costs on gait and cognitive performance in high-Aβ (PiB(+)) and low-Aβ (PiB(-)) groups and examined th ...[more]
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