Age-related differences in locus coeruleus intensity across a demographically diverse sample

Area of Science:

• Neuroimaging
• Neurodegenerative Diseases
• Aging Brain

Background:

• The locus coeruleus (LC) is implicated in neurodegeneration, with changes potentially starting in middle age.
• Lifespan trajectories of LC signal intensity and demographic variations are poorly understood.
• Early detection of neurodegenerative diseases may benefit from understanding LC changes.

Purpose of the Study:

• To investigate the trajectory of in vivo locus coeruleus (LC) signal intensity across the adult lifespan.
• To examine demographic variations in LC signal intensity.
• To explore the relationship between LC signal intensity and cognitive function in older adults.

Main Methods:

• T1-weighted turbo spin echo magnetic resonance imaging (MRI) was used to measure LC signal intensity.
• 134 participants aged 19-86 years were recruited, with a focus on racial diversity (41% non-White).
• Statistical analyses examined lifespan trends and demographic influences on LC signal intensity.

Main Results:

• LC signal intensity was lowest in early adulthood, peaked around age 60, and declined in older adults.
• The caudal LC showed the greatest signal intensity and decrease in older age.
• Rostral LC signal intensity was higher in women and Black participants and positively associated with fluid cognition in high-performing older adults.

Conclusions:

• LC signal intensity follows a distinct lifespan trajectory, with demographic modifications.
• These findings suggest LC signal intensity changes may relate to differential susceptibility to neurocognitive aging.
• Further research into LC signal intensity may offer insights into early neurodegenerative disease detection.