Age differences in diffusivity in the locus coeruleus and its ascending noradrenergic tract
Shai Porat,
Francesca Sibilia,
Josephine Yoon,
Yonggang Shi,
Martin J. Dahl,
Markus Werkle-Bergner,
Sandra Düzel,
Nils Bodammer,
Ulman Lindenberger,
Simone Kühn,
Mara Mather
Affiliations
Shai Porat
University of Southern California, Dept. of Gerontology, United States; Corresponding author at: 3715 McClintock Ave., Leonard Davis School of Gerontology, USC, Los Angeles CA 90089, United States.
Francesca Sibilia
University of Southern California, Keck School of Medicine, United States
Josephine Yoon
University of Southern California, Dept. of Gerontology, United States
Yonggang Shi
University of Southern California, Keck School of Medicine, United States
Martin J. Dahl
University of Southern California, Dept. of Gerontology, United States; Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Markus Werkle-Bergner
Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Sandra Düzel
Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Nils Bodammer
Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Ulman Lindenberger
Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Simone Kühn
Max Planck Institute for Human Development, Center for Lifespan Psychology, Germany
Mara Mather
University of Southern California, Dept. of Gerontology, United States
The noradrenergic locus coeruleus (LC) is a small brainstem nucleus that promotes arousal and attention. Recent studies have examined the microstructural properties of the LC using diffusion-weighted magnetic resonance imaging and found unexpected age-related differences in fractional anisotropy - a measure of white matter integrity. Here, we used two datasets (Berlin Aging Study-II, N = 301, the Leipzig Study for Mind-Body-Emotion Interactions, N = 220), to replicate published findings and expand them by investigating diffusivity in the LC's ascending noradrenergic bundle. In younger adults, LC fractional anisotropy was significantly lower, compared to older adults. However, in the LC's ascending noradrenergic bundle, we observed significantly higher fractional anisotropy in younger adults, relative to older adults. These findings indicate that diffusivity in the LC versus the ascending noradrenergic bundle are both susceptible to structural changes in aging that have opposing effects on fractional anisotropy.
