Neuromelanin marks the spot: identifying a locus coeruleus biomarker of cognitive reserve in healthy aging

NEUROBIOLOGY OF AGING

卷:37

Article

Clewett, David V.¹  Lee, Tae-Ho²  Greening, Steven^2,3,4  Ponzio, Allison³  Margalit, Eshed⁵  Mather, Mara^1,2,3 

[1] Univ So Calif, Neurosci Grad Program, Los Angeles, CA 90089 USA

[2] Univ So Calif, Dept Psychol, Los Angeles, CA 90089 USA

[3] Univ So Calif, Davis Sch Gerontol, Los Angeles, CA 90089 USA

[4] Louisiana State Univ, Dept Psychol, Baton Rouge, LA 70803 USA

[5] Univ So Calif, Dornsife Coll Letters & Sci, Los Angeles, CA 90089 USA

关键词: Locus coeruleus;    Aging;    Norepinephrine;    Cognitive reserve;    Brain reserve;    Sex;    Gender;   

DOI  :  10.1016/j.neurobiolaging.2015.09.019

来源: Elsevier

【 摘 要 】

Leading a mentally stimulating life may build up a reserve of neural and mental resources that preserve cognitive abilities in late life. Recent autopsy evidence links neuronal density in the locus coeruleus (LC), the brain's main source of norepinephrine, to slower cognitive decline before death, inspiring the idea that the noradrenergic system is a key component of reserve (Robertson, I. H. 2013. A noradrenergic theory of cognitive reserve: implications for Alzheimer's disease. Neurobiol. Aging. 34, 298-308). Here, we tested this hypothesis using neuromelanin-sensitive magnetic resonance imaging to visualize and measure LC signal intensity in healthy younger and older adults. Established proxies of reserve, including education, occupational attainment, and verbal intelligence, were linearly correlated with LC signal intensity in both age groups. Results indicated that LC signal intensity was significantly higher in older than younger adults and significantly lower in women than in men. Consistent with the LC-reserve hypothesis, both verbal intelligence and a composite reserve score were positively associated with LC signal intensity in older adults. LC signal intensity was also more strongly associated with attentional shifting ability in older adults with lower cognitive reserve. Together these findings link in vivo estimates of LC neuromelanin signal intensity to cognitive reserve in normal aging. (C) 2016 Elsevier Inc. All rights reserved.

【 授权许可】

Free