The gray matter matters

A synopsis of an article at Scientific American indicates there may have been a breakthrough in understanding how much more important the "white matter" of the brain may be:

Key Concepts:

* White matter, long thought to be passive tissue, actively affects how the brain learns and dysfunctions.

* Although gray matter (composed of neurons) does the brain's thinking and calculating, white matter (composed of myelin-coated axons) controls the signals that neurons share, coordinating how well brain regions work together.

* A new type of magnetic resonance technology, called diffusion tensor imaging (DTI), has for the first time shown white matter in action, revealing its underappreciated role.

* Myelin is only partially formed at birth and gradually develops in different regions throughout our 20s. The timing of growth and degree of completion can affect learning, self-control (and why teenagers may lack it), and mental illnesses such as schizophrenia, autism and even pathological lying.

H/T to Sasha Wagner-Adamo for the link.