title: Education mitigates age-related decline in N-Acetylaspartate levels.
abstract: BACKGROUND
  Greater educational attainment is associated with better neurocognitive health in older adults and is thought to reflect a measure of cognitive reserve. In vivo neuroimaging tools have begun to identify the brain systems and networks potentially responsible for reserve.
  
  
  METHODS
  We examined the relationship between education, a commonly used proxy for cognitive reserve, and N-acetylaspartate (NAA) in neurologically healthy older adults (N=135; mean age=66 years). Using single voxel MR spectroscopy, we predicted that higher levels of education would moderate an age-related decline in NAA in the frontal cortex.
  
  
  RESULTS
  After controlling for the variance associated with cardiorespiratory fitness, sex, annual income, and creatine levels, there were no significant main effects of education (B=0.016, P=0.787) or age (B=-0.058, P=0.204) on NAA levels. However, consistent with our predictions, there was a significant education X age interaction such that more years of education offset an age-related decline in NAA (B=0.025, P=0.031). When examining working memory via the backwards digit span task, longer span length was associated with greater education (P<0.01) and showed a trend with greater NAA concentrations (P<0.06); however, there was no age X education interaction on digit span performance nor a significant moderated mediation effect between age, education, and NAA on digit span performance.
  
  
  CONCLUSIONS
  Taken together, these results suggest that higher levels of education may attenuate an age-related reduction in neuronal viability in the frontal cortex.
authors: Department of Psychology, University of Pittsburgh Pittsburgh, Pennsylvania ; Center for the Neural Basis of Cognition, University of Pittsburgh Pittsburgh, Pennsylvania ; Center for Neuroscience, University of Pittsburgh Pittsburgh, Pennsylvania.
authors: Kirk I
authors: KI
authors: Erickson
authors: Department of Psychology, University of Pittsburgh Pittsburgh, Pennsylvania ; Center for the Neural Basis of Cognition, University of Pittsburgh Pittsburgh, Pennsylvania.
authors: Regina L
authors: RL
authors: Leckie
authors: Department of Psychology, University of Pittsburgh Pittsburgh, Pennsylvania ; Center for the Neural Basis of Cognition, University of Pittsburgh Pittsburgh, Pennsylvania.
authors: Andrea M
authors: AM
authors: Weinstein
authors: Center for Neuroscience, University of Pittsburgh Pittsburgh, Pennsylvania.
authors: Polina
authors: P
authors: Radchenkova
authors: Department of Bioengineering, University of Illinois Urbana, Illinois ; Beckman Institute for Advanced Science and Technology, University of Illinois Urbana, Illinois.
authors: Bradley P
authors: BP
authors: Sutton
authors: Department of Psychology, Ohio State University Columbus, Ohio.
authors: Ruchika Shaurya
authors: RS
authors: Prakash
authors: Department of Psychology, University of Iowa Iowa City, Iowa.
authors: Michelle W
authors: MW
authors: Voss
authors: Beckman Institute for Advanced Science and Technology, University of Illinois Urbana, Illinois ; Department of Psychology, University of Illinois Urbana, Illinois.
authors: Laura
authors: L
authors: Chaddock-Heyman
authors: Beckman Institute for Advanced Science and Technology, University of Illinois Urbana, Illinois ; Department of Kinesiology and Community Health, University of Illinois Urbana, Illinois.
authors: Edward
authors: E
authors: McAuley
authors: Beckman Institute for Advanced Science and Technology, University of Illinois Urbana, Illinois ; Department of Psychology, University of Illinois Urbana, Illinois.
authors: Arthur F
authors: AF
authors: Kramer
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology / Q000523:psychology; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D058245:Cognitive Reserve / Q000502:physiology*; D004522:Educational Status; D005260:Female; D005625:Frontal Lobe / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate
keywords: Aging; brain reserve; cognitive reserve; education; fitness