Botulinum Toxin Injections Improve Depression
Jim Kling
March 26, 2014
There are 2 possible explanations for the improvement in depressive symptoms, explained Dr. Magid.
The first is that the botulinum injections made it difficult for the subjects to frown. If individuals smile more and frown less, they are likely to have better social experiences, which could lift mood.
The second possibility, favored by Dr. Magid, is a biologic explanation. MRI studies have shown that when people are unable to make angry facial expressions because of botulinum injections to the glabellar region, there is less activity in the amygdala than expected. Such a connection could be mediated by the trigeminal nerve, which links the glabellar region to the brain stem and amygdala and is the control center of anxiety, trauma, and the heightened fear response.
If a person can't frown, the brain does not register a frown, and the amygdala does not get the trigger that the person is upset, Dr. Reichenberg told Medscape Medical News.
"Anxious depressed" patients seemed to do better with the treatment than those with melancholia. "It could be a first-line therapy or an augmentation strategy," he suggested...
