Once the researchers established that Fat Sand Rats and humans had a similar reaction to light, the team explored whether common medications or other SAD therapies would be as effective in their rat population. These studies included a variety of medications commonly used to treat the disorder in humans, as well as a program of exposing the depressed sand rats to brighter light for one hour every morning or evening.
More than a placebo
According to Prof. Kronfeld-Schor, the results were surprising. The medications were effective in treating the sand rats' depression, but even more effective was the daily exposure to bright light in the mornings, a common treatment for human SAD. "Humans have been using this treatment for a long time," she explains, "but many of us thought that a large part of its success was based on the placebo effect. For the first time, we've found it to be effective in animals as well, which weakens the possibility of the placebo effect."
The breakthrough, says Prof. Kronfeld-Schor, is the discovery of a superior and viable animal model for studying affective disorders. Though several biological mechanisms for SAD have been proposed, they have not been scientifically proven. A good animal model to study the mechanisms of SAD will advance understanding of the disorder, help screen for effective treatments and allow for the development of new therapies.
|Contact: George Hunka|
American Friends of Tel Aviv University