Bioethics Blogs

Snapshots of Life: Tracing the Fibers of Addiction

DTI fiber tracking image

Credit: John D. Olson, Paul W. Czoty Michelle Bell, Wake Forest School of Medicine, Winston-Salem, NC

This may look like a light-hearted piece of string art, but it’s actually part of a very serious effort to understand what happens to the brain when it’s strung out on drugs. The image, one of the winners of the Federation of American Societies for Experimental Biology’s 2013 BioArt competition, was created with an advanced form of magnetic resonance imaging called Diffusion Tensor Imaging (DTI).

DTI works by detecting the movement of water in the nerve cells of a living brain. By determining which direction water is flowing in axons, the long processes that convey signals to other neurons, researchers can figure out whether the neurons are stretching from the left to right side of the brain (red), top to bottom (blue), or front to back (green). This data is then used to construct a three-dimensional view of the brain and its connections.

In this particular image, we see the brain of a monkey before the animal was exposed to cocaine. The NIH-funded team is using DTI to study the changes that occur after short- and long-term cocaine use, and also after a period of recovery. It is well known that cocaine users behave erratically, are sometimes violent, and show poor decision making. But the biology behind such behaviors isn’t well understood. Do the behaviors arise because neurons die and connections are lost? Does the brain rewire itself with long-term cocaine use? Or does cocaine damage the structure of the neurons and cause them to leak water and function abnormally?

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.