This study investigates how the brain’s white matter (WM) changes with age by examining the relationships between brain activity and WM microstructure using a method called Functional Correlation Tensors (FCTs) derived from resting-state fMRI data. FCTs are used to analyze the directionality and strength of brain activity correlations in white matter, helping researchers understand how brain communication and structure interact, especially in aging.
The researchers studied data from 461 cognitively normal adults, aged 42 to 95, sourced from a publicly available database. By looking at FCT metrics—such as how signals move along and across WM tracts—they were able to map out patterns of brain activity and measure how these change with age. The analysis showed that some areas of white matter experience declines in functional correlations (weaker communication) with age, while other areas see increases. Additionally, women appeared to show age-related changes in more brain regions compared to men, although the interaction between age and sex was not statistically significant.
This study demonstrates that FCTs follow a consistent spatial distribution across individuals, offering a reproducible way to quantify subtle changes in WM as people age. The results provide new insights into the effects of aging on brain structure and function, potentially informing future research into brain health, cognitive decline, and neurological diseases.
