title: The association between aerobic fitness and cognitive function in older men mediated by frontal lateralization.
abstract: Previous studies have shown that higher aerobic fitness is related to higher cognitive function and higher task-related prefrontal activation in older adults. However, a holistic picture of these factors has yet to be presented. As a typical age-related change of brain activation, less lateralized activity in the prefrontal cortex during cognitive tasks has been observed in various neuroimaging studies. Thus, this study aimed to reveal the relationship between aerobic fitness, cognitive function, and frontal lateralization. Sixty male older adults each performed a submaximal incremental exercise test to determine their oxygen intake (V·O2) at ventilatory threshold (VT) in order to index their aerobic fitness. They performed a color-word Stroop task while prefrontal activation was monitored using functional near infrared spectroscopy. As an index of cognitive function, Stroop interference time was analyzed. Partial correlation analyses revealed significant correlations among higher VT, shorter Stroop interference time and greater left-lateralized dorsolateral prefrontal cortex (DLPFC) activation when adjusting for education. Moreover, mediation analyses showed that left-lateralized DLPFC activation significantly mediated the association between VT and Stroop interference time. These results suggest that higher aerobic fitness is associated with cognitive function via lateralized frontal activation in older adults.
authors.affiliation: Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8574, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Hyodo
authors.affiliation: Applied Cognitive Neuroscience Lab., Research and Development Initiatives, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Ippeita
authors.initials: I
authors.lastname: Dan
authors.affiliation: Applied Cognitive Neuroscience Lab., Research and Development Initiatives, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kyutoku
authors.affiliation: Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8574, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Suwabe
authors.affiliation: Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8574, Japan; Department of Neurobiology and Behavior, University of California, Irvine, 213 Qureshey Research Laboratory, Irvine CA 92697-3800, USA.
authors.forename: Kyeongho
authors.initials: K
authors.lastname: Byun
authors.affiliation: Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8574, Japan.
authors.forename: Genta
authors.initials: G
authors.lastname: Ochi
authors.affiliation: Department of Health and Nutrition, Yonezawa Nutrition University of Yamagata Prefecture, Yonezawa 992-0025, Japan.
authors.forename: Morimasa
authors.initials: M
authors.lastname: Kato
authors.affiliation: Laboratory of Exercise Biochemistry and Neuroendocrinology, Faculty of Health and Sport Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8574, Japan. Electronic address: hsoya@taiiku.tsukuba.ac.jp.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Soya
mesh_terms: D000368:Aged; D003071:Cognition / Q000502:physiology*; D005080:Exercise Test; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D010809:Physical Fitness / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D019265:Spectroscopy, Near-Infrared; D057190:Stroop Test
keywords: Aerobic fitness; Aging; Frontal lateralization; Functional near infrared spectroscopy; Prefrontal cortex; Stroop task