Science Daily 5/7/2021
A new University of Iowa study challenges the idea that gray matter (the neurons that form the cerebral cortex) is more important than white matter (the myelin covered axons that physically connect neuronal regions) when it comes to cognitive health and function. The findings may help neurologists better predict the long-term effects of strokes and other forms of traumatic brain injury.
“The most unexpected aspect of our findings was that damage to gray matter hubs of the brain that are really interconnected with other regions didn’t really tell us much about how poorly people would do on cognitive tests after brain damage. On the other hand, people with damage to the densest white matter connections did much worse on those tests,” explains Justin Reber, PhD, a UI postdoctoral research fellow in psychology and first author on the study. “This is important because both scientists and clinicians often focus almost exclusively on the role of gray matter. This study is a reminder that connections between brain regions might matter just as much as those regions themselves, if not more so.”