title: Concurrent and longitudinal relationships between cognitive activity, cognitive performance, and brain volume in older adult women.
abstract: OBJECTIVE
  We investigated (a) cross-sectional associations between cognitive activity, cognitive performance, and MRI measures and (b) longitudinal associations between cognitive activity and change in cognitive performance, using structural equation modeling (SEM).
  
  
  METHODS
  Women's Health Initiative Memory Study (WHIMS) Extension participants who continued annual neuropsychological assessments by telephone and completed a concurrent questionnaire of cognitive activities and MRI scans were included (mean age = 81.4 years; N = 393). Cognitive performance was measured by tests of attention, working memory, verbal fluency, executive function, and memory. Cognitive activity was measured by self-reported participation in a variety of cognitive activities (e.g., reading books, playing games, computer activities; N = 11 items) during the previous 12 months. MRI measures included gray and white matter normal and white matter lesion volumes.
  
  
  RESULTS
  SEM demonstrated a significant association between cognitive activity and baseline cognitive performance but not change over 2-3 years. Gray and white matter was associated with cognitive performance but not cognitive activity. All effects remained significant after modeling covariates (age, education, depressive symptoms, WHIMS intervention assignment, and intracranial volume).
  
  
  CONCLUSIONS
  Cognitive activity benefits current cognitive performance but is not associated with change over 2-3 years. Cognitive activity and MRI volumes are independently associated with cognitive performance, suggesting distinct cognitive and brain reserve constructs.
authors.affiliation: Department of Social Sciences and Health Policy, Wake Forest School of Medicine, Winston-Salem, North Carolina. alvaugha@wakehealth.edu.
authors.forename: Leslie
authors.initials: L
authors.lastname: Vaughan
authors.affiliation: Department of Psychology, University of Pittsburgh, Pennsylvania.
authors.forename: Kirk I
authors.initials: KI
authors.lastname: Erickson
authors.affiliation: Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Espeland
authors.affiliation: Department of Kinesiology, University of Maryland, College Park.
authors.forename: J Carson
authors.initials: JC
authors.lastname: Smith
authors.affiliation: Division of General Internal Medicine, University of Pittsburgh, Pennsylvania.
authors.forename: Hilary A
authors.initials: HA
authors.lastname: Tindle
authors.affiliation: Department of Social Sciences and Health Policy, Wake Forest School of Medicine, Winston-Salem, North Carolina. Department of Psychiatry and Behavioral Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Rapp
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*
keywords: Cognition; Cognitive activity; Longitudinal change; MRI; SEM.