title: Neural correlates of older adults' self-overestimation of stepping-over ability.
abstract: A growing body of literature indicates that cognitively intact older adults tend to overestimate their physical functioning (e.g., step-over ability), which may lead to fall risk. However, the neural correlates underlying this phenomenon are still unclear. We therefore investigated the neural basis of older adults' self-overestimation of stepping-over ability. A total of 108 well-functioning community dwelling older adults (mean age = 73.9 years) performed step-over tests (SOT) in two ways: self-estimation of step-over ability and an actual step-over task. During the self-estimation task, participants observed a horizontal bar at a distance of 7 m and estimated the maximum height (EH) of successful SOT trials. The actual SOT was then performed to determine the actual maximum height (AH) of successful trials. Participants also underwent positron emission tomography with18F-fluorodeoxyglucose at rest to assess cerebral neural activity. The SOT showed that 22.2 % of participants overestimated their step-over ability. A regression analysis adjusted for potential covariates showed that increased self-estimation error (difference between EH and AH) was correlated with lower glucose metabolism in the bilateral orbitofrontal cortex (OFC) and left frontal pole. Only the significant correlation between self-estimation error and OFC activity persisted after correcting for multiple comparisons. For well-functioning healthy older adults, overlooking one's own functional decline may be influenced by reduced metabolic activity in the anterior prefrontal cortex, particularly in the OFC. Our findings also suggest that functional decline in the OFC prevents older adults from updating the qualitative/quantitative values of their impaired physical abilities.
authors.affiliation: Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan. r_sakurai@hotmail.co.jp.|Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan. r_sakurai@hotmail.co.jp.|Research Fellow of the Japan Society for the Promotion of Science, Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyoda-ku, Tokyo, 102-0083, Japan. r_sakurai@hotmail.co.jp.
authors.forename: Ryota
authors.initials: R
authors.lastname: Sakurai
authors.affiliation: Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Fujiwara
authors.affiliation: Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Yasunaga
authors.affiliation: Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Research Team for Social Participation and Community Health, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Yoh
authors.initials: Y
authors.lastname: Murayama
authors.affiliation: Health Promotion Science, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji-shi, Tokyo, 192-0397, Japan.
authors.forename: Kuniyasu
authors.initials: K
authors.lastname: Imanaka
authors.affiliation: Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Kanosue
authors.affiliation: Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ishii
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism / Q000523:psychology*; D003071:Cognition; D003430:Cross-Sectional Studies; D003710:Demography; D005080:Exercise Test; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000032:analysis / Q000378:metabolism; D006801:Humans; D057187:Independent Living; D008297:Male; D049268:Positron-Emission Tomography; D017397:Prefrontal Cortex / Q000737:chemistry / Q000378:metabolism*; D012044:Regression Analysis; D012306:Risk; D012647:Self-Assessment; D011795:Surveys and Questionnaires
chemical_list: D019788:Fluorodeoxyglucose F18; D005947:Glucose
keywords: FDG-PET; Older adults; Orbitofrontal cortex; Self-estimation; Step-over ability