title: Age in high-functioning healthy men is associated with nonlinear decline in some 'executive' functions in late middle age.
abstract: OBJECTIVE
  Age-related cognitive decline might involve selective deterioration of specific brain systems. We studied the relationship between age and cognition by comparing cognitive function of older and younger high functioning men.
  
  
  METHODS
  A cross-sectional study comparing neuropsychological test battery performance of younger (18-60 years) and older (61-85 years) men.
  
  
  RESULTS
  Older men showed impaired psychomotor speed, working memory, attention, declarative verbal memory and executive functions. Impairment in executive function was prominent and not explained by psychomotor slowing, impaired working memory or attention. Regression models showed a non-linear relationship between age and executive function with a change of slopes in the mid-50s. The relationship of age with verbal memory was linear.
  
  
  CONCLUSIONS
  The nonlinear change in late middle age is consistent with the hypothesis that an age-related selective diatheses impacts selectively on executive function.
authors.affiliation: Brain Behavior Laboratory, Sha'ar Menashe Mental Health Center, Sha'ar Menashe, Israel. mdsilver@tx.technion.ac.il
authors.forename: Henry
authors.initials: H
authors.lastname: Silver
authors.forename: Craig
authors.initials: C
authors.lastname: Goodman
authors.forename: Warren
authors.initials: W
authors.lastname: Bilker
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D003071:Cognition / Q000502:physiology; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D017711:Nonlinear Dynamics; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012044:Regression Analysis; D014888:Wechsler Scales; D055815:Young Adult