Severe depression often paralyzes its sufferers with a sense of overwhelminglistlessness and lethargy At the same time, however, some parts of the depressive's brain may be working overtime, reports Wayne Drevets, M.D., of the University of Pittsburgh Medical Center.
Drevets presented his research on the amygdala--a small brain region that plays a central role in emotional learning and behavior--at the annual meeting of the Society for Neuroscience in October. He used positron emission tomography, or PET, to measure the glucose metabolism of the amygdalas of people with different types of depression. Abnormally high metabolism, says Drevets, would indicate that the cells in that region are especially busy communicating with each other, perhaps producing exaggerated emotional states like obsessive ruminations and panic attacks. And indeed, he found this heightened activity in the brains of two groups of patients: those with manic-depressive illness, and those with the kind of depression that runs in families and is thought to be caused, at least in part, by genetic factors.
