According to the study, published in the journal Nature Neuroscience, researchers at Duke University found areas of pain in the mouse brain that could close down. It is located in the amygdala, which is often considered a hub for negative emotions and reactions, such as being responsible for combat or flight responses and common anxiety.
“People believe there is a central position for pain relief, and that’s why placebo works. “The question is which part of the brain is the center that stops pain, ” said Wang Fan, senior author of the paper and a distinguished professor of neurobiology at Duke University School of Medicine. Most previous studies have focused on areas where pain stimulates. “But there are a lot of areas that deal with pain, and you have to shut them all down to stop the pain. And the center can shut down the pain on its own. “
The researchers found that general anesthesia activates a group of inhibitory neurons in the middle of the amygdala, which they call CeAga neurons (CeA stands for “central amygdala”; ga means general anesthesia activation). The central amygdala in mice is larger than humans, and the team found that CeAga is connected to many different regions of the brain.
They found that at least 16 brain centers processed sensory or emotional information about pain, receiving suppressed inputs from CeAga. Using a technique called optogenetics, the researchers used light to activate a small group of cells in the brain, and by activating CeAga neurons, they could stop the self-care behavior shown in mice when they felt uncomfortable.