title: fMRI and sleep correlates of the age-related impairment in motor memory consolidation.
abstract: Behavioral studies indicate that older adults exhibit normal motor sequence learning (MSL), but paradoxically, show impaired consolidation of the new memory trace. However, the neural and physiological mechanisms underlying this impairment are entirely unknown. Here, we sought to identify, through functional magnetic resonance imaging during MSL and electroencephalographic (EEG) recordings during daytime sleep, the functional correlates and physiological characteristics of this age-related motor memory deficit. As predicted, older subjects did not exhibit sleep-dependent gains in performance (i.e., behavioral changes that reflect consolidation) and had reduced sleep spindles compared with young subjects. Brain imaging analyses also revealed that changes in activity across the retention interval in the putamen and related brain regions were associated with sleep spindles. This change in striatal activity was increased in young subjects, but reduced by comparison in older subjects. These findings suggest that the deficit in sleep-dependent motor memory consolidation in elderly individuals is related to a reduction in sleep spindle oscillations and to an associated decrease of activity in the cortico-striatal network.
authors.affiliation: The Brain & Mind Institute, Department of Psychology, Western University, London, Ontario, Canada; Functional Neuroimaging Unit, University of Montreal, Montreal, Quebec, Canada; Department of Psychology, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Fogel
authors.forename: Genevieve
authors.initials: G
authors.lastname: Albouy
authors.forename: Catherine
authors.initials: C
authors.lastname: Vien
authors.forename: Romana
authors.initials: R
authors.lastname: Popovicci
authors.forename: Bradley R
authors.initials: BR
authors.lastname: King
authors.forename: Rick
authors.initials: R
authors.lastname: Hoge
authors.forename: Saad
authors.initials: S
authors.lastname: Jbabdi
authors.forename: Habib
authors.initials: H
authors.lastname: Benali
authors.forename: Avi
authors.initials: A
authors.lastname: Karni
authors.forename: Pierre
authors.initials: P
authors.lastname: Maquet
authors.forename: Julie
authors.initials: J
authors.lastname: Carrier
authors.forename: Julien
authors.initials: J
authors.lastname: Doyon
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D017440:Photoperiod; D012890:Sleep / Q000502:physiology*; D055815:Young Adult
keywords: EEG; aging; cerebellum; fMRI; hippocampus; memory consolidation; motor sequence learning; putamen; sleep; spindles