Gray or White Brain Matter

The results of a study by researchers at the University of Iowa have challenged the commonly held idea that when it comes to brain health and function, gray matter (the neurons that form the cerebral cortex) is more important than white matter (the myelin covered axons that physically connect neuronal regions in the brain) This new study published in the Proceedings of the National Academy of Sciences in the US reported on the analysis of brain scans and cognitive or thinking-function tests from over 500 people with localized areas of brain damage caused by forms of brain injury, including strokes. Looking at the location of the brain damage, also known as lesions, the UI team correlated the level of connectedness of the damaged areas with the level of cognitive or thinking disability the patient experienced. Their findings suggest that damage to highly connected regions of white matter is more predictive of cognitive or thinking impairment than damage to highly connected gray-matter hubs. More tomorrow.