Brain Network Segregation and Glucose Energy Utilization: Relevance for Age-Related Differences in Cognitive Function

Area of Science:

• Neuroscience
• Cognitive Aging
• Brain Imaging

Background:

• The brain's small-world network organization is vital for energy efficiency.
• Brain network segregation and glucose metabolism vary across the lifespan.
• The interplay between network changes and cognition with age is not fully understood.

Purpose of the Study:

• To investigate the relationship between brain network segregation, glucose metabolism, and cognitive performance across adulthood.
• To determine if age-related changes in brain networks and metabolism influence cognitive function.

Main Methods:

• Utilized fluorodeoxyglucose-positron emission tomography (FDG-PET) and resting-state functional magnetic resonance imaging (rs-fMRI).
• Analyzed data from 88 participants aged 18-73 years.
• Assessed brain network segregation and relative glucose metabolism in sensorimotor and association networks.

Main Results:

• Brain network segregation decreased with age in both sensorimotor and association networks.
• Glucose metabolism showed an age-by-network interaction: decreasing in association networks but increasing in sensorimotor networks.
• Lower network segregation correlated with greater age-related changes in glucose metabolism.
• Sensorimotor network segregation and metabolism mediated age-related differences in spatial cognition and response time, respectively.

Conclusions:

• Sensorimotor network segregation and glucose metabolism are key factors in age-related cognitive changes.
• Targeting somatosensory networks may offer therapeutic potential for mitigating cognitive decline in aging individuals.