title: Changes in brain network efficiency and working memory performance in aging.
abstract: Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory.
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
authors: Matthew L
authors: ML
authors: Stanley
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America; Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
authors: Sean L
authors: SL
authors: Simpson
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America; Department of Psychology, Wake Forest University, Winston-Salem, North Carolina, United States of America.
authors: Dale
authors: D
authors: Dagenbach
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
authors: Robert G
authors: RG
authors: Lyday
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America; Department of Radiology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
authors: Jonathan H
authors: JH
authors: Burdette
authors: Laboratory for Complex Brain Networks, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America; Department of Radiology, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
authors: Paul J
authors: PJ
authors: Laurienti
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D003071:Cognition; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D009434:Neural Pathways; D009483:Neuropsychological Tests; D012044:Regression Analysis; D055815:Young Adult