White Matter Counts: Brain Connections Help Us Do 2 + 2

HIGHWAYS OF THE BRAIN White matter is a lot like the highways of the brain. These highways connect different parts of the brain and pass information from one part of the brain to others. The better built the highways are, the easier it is to do things like read and do math. These connections or highways are called tracts, and each tract will connect different parts of the brain. There is a special kind of brain imaging called diffusion tensor imaging (DTI) that helps us study white matter and how strong the connections are. In recent years, a lot of studies have used DTI to look at how the connections in our brain might help us think. You can also make really cool colored pictures from DTI scans that show you in which direction the tract is going (Blue = Top of the head to the bottom of the head, Red/Pink = Left to right, Green = Front of the head to the back of the head). For every part of the brain, you can calculate a number between 0 The brain is made of many millions of cells, and different kinds of cells have different functions. The part of the brain that looks darker in pictures is called gray matter (Figure 1). The cells in this part of the brain help us do things like think and process information. White matter looks lighter and has different kinds of cells that have a fatty layer of insulation around them called myelin. This layer helps signals go through the cells, and makes information transfer faster. It is also what makes white matter look white! Gray matter and white matter work together to help us do all sorts of things like think, sing, and do school work.