title: Working memory in middle-aged males: age-related brain activation changes and cognitive fatigue effects.
abstract: We examined the effects of aging and cognitive fatigue on working memory (WM) related brain activation using functional magnetic resonance imaging. Age-related differences were investigated in 13 young and 16 middle-aged male school teachers. Cognitive fatigue was induced by sustained performance on cognitively demanding tasks (compared to a control condition). Results showed a main effect of age on left dorsolateral prefrontal and superior parietal cortex activation during WM encoding; greater activation was evident in middle-aged than young adults regardless of WM load or fatigue condition. An interaction effect was found in the dorsomedial prefrontal cortex (DMPFC); WM load-dependent activation was elevated in middle-aged compared to young in the control condition, but did not differ in the fatigue condition due to a reduction in activation in middle-aged in contrast to an increase in activation in the young group. These findings demonstrate age-related activation differences and differential effects of fatigue on activation in young and middle-aged adults.
authors.affiliation: School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, The Netherlands; LEARN! Research Institute, Faculty of Psychology and Education, VU University Amsterdam, The Netherlands. Electronic address: e.b.klaassen@vu.nl.
authors.forename: Elissa B
authors.initials: EB
authors.lastname: Klaassen
authors.affiliation: Center for Functional Magnetic Resonance Imaging, Department of Radiology, University of California San Diego (UCSD), San Diego, USA. Electronic address: eevers@ucsd.edu.
authors.forename: Elisabeth A T
authors.initials: EA
authors.lastname: Evers
authors.affiliation: School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, The Netherlands; Centre for Learning Sciences and Technologies (CELSTEC), Open University, The Netherlands; LEARN! Research Institute, Faculty of Psychology and Education, VU University Amsterdam, The Netherlands. Electronic address: Renate.deGroot@ou.nl.
authors.forename: Renate H M
authors.initials: RH
authors.lastname: de Groot
authors.affiliation: School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University, The Netherlands; Department of Radiology, Maastricht University Medical Centre, The Netherlands. Electronic address: w.backes@mumc.nl.
authors.forename: Walter H
authors.initials: WH
authors.lastname: Backes
authors.affiliation: Department of Psychiatry, VU University Medical Centre, & Neuroscience Campus Amsterdam, The Netherlands. Electronic address: DJ.Veltman@vumc.nl.
authors.forename: Dick J
authors.initials: DJ
authors.lastname: Veltman
authors.affiliation: LEARN! Research Institute, Faculty of Psychology and Education, VU University Amsterdam, The Netherlands. Electronic address: j.jolles@vu.nl.
authors.forename: Jelle
authors.initials: J
authors.lastname: Jolles
mesh_terms: D000328:Adult; D000367:Age Factors; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000503:physiopathology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D008570:Memory, Short-Term / Q000502:physiology*; D005222:Mental Fatigue / Q000150:complications* / Q000209:etiology / Q000473:pathology; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D064232:Visual Analog Scale
chemical_list: D010100:Oxygen
keywords: Aging; Cognitive fatigue; Functional magnetic resonance imaging; Working memory