title: Age-related changes to the neural correlates of working memory which emerge after midlife.
abstract: Previous research has indicated that the neural processes which underlie working memory change with age. Both age-related increases and decreases to cortical activity have been reported. This study investigated which stages of working memory are most vulnerable to age-related changes after midlife. To do this we examined age-differences in the 13 Hz steady state visually evoked potential (SSVEP) associated with a spatial working memory delayed response task. Participants were 130 healthy adults separated into a midlife (40-60 years) and an older group (61-82 years). Relative to the midlife group, older adults demonstrated greater bilateral frontal activity during encoding and this pattern of activity was related to better working memory performance. In contrast, evidence of age-related under activation was identified over left frontal regions during retrieval. Findings from this study suggest that after midlife, under-activation of frontal regions during retrieval contributes to age-related decline in working memory performance.
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: Helen N
authors.initials: HN
authors.lastname: Macpherson
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: David J
authors.initials: DJ
authors.lastname: White
authors.affiliation: Department of Psychiatry, Academic Unit for Psychiatry of Old Age, St. Vincent's Aged Psychiatry Service, St. Georges Hospital, University of Melbourne Melbourne, VIC, Australia.
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Ellis
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: Con
authors.initials: C
authors.lastname: Stough
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Camfield
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Silberstein
authors.affiliation: Centre for Human Psychopharmacology, Swinburne University Hawthorn, VIC, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Pipingas
keywords: SSVEP; aging; compensation; middle age; midlife; working memory