Newswise — Activating a circuit between the amygdala and brainstem relieves pain and reduces defensive behaviors in rats, according to research recently published in JNeurosci.
People with pain often experience psychological comorbidities like anxiety and depression, which can end up making their prognosis worse. A pathway from the amygdala to a nucleus in the brainstem may offer a way to treat pain’s toll on both the body and the mind. Hogri et al. activated the circuit in rats and measured their response to chemical, mechanical, and thermal pain stimuli. Stimulating the circuit decreased the brainstem’s response to all three stimuli, indicating pain relief. In a separate situation, stimulating the circuit decreased the rats’ defensive behaviors in response to a threat. It also increased reward and feeding behavior, a sign the rats felt safe. The combination of these behavior changes indicates the circuit steers rats out of a negative emotional state and into a positive one.
In humans, there is not yet a way to stimulate a specific brain circuit. Existing brain stimulation technologies are not precise enough and could activate neighboring circuits that could increase pain and negative emotions. But addressing these technical roadblocks could lead to a treatment that addresses both the pain itself and the negative feelings it generates.
Paper title: GABAergic CaMKIIα+ Amygdala Output Attenuates Pain and Modulates Emotional-motivational Behaviour via Parabrachial Inhibition
JNeurosci, the Society for Neuroscience's first journal, was launched in 1981 as a means to communicate the findings of the highest quality neuroscience research to the growing field. Today, the journal remains committed to publishing cutting-edge neuroscience that will have an immediate and lasting scientific impact, while responding to authors' changing publishing needs, representing breadth of the field and diversity in authorship.
About The Society for Neuroscience
The Society for Neuroscience is the world's largest organization of scientists and physicians devoted to understanding the brain and nervous system. The nonprofit organization, founded in 1969, now has nearly 37,000 members in more than 90 countries and over 130 chapters worldwide.