Study finds direct connection between brain and vagus nerve

Researchers at the University of Colorado Anschutz Medical Campus have discovered a clear relationship between vagus nerve stimulation and the brain’s learning centres. The discovery may open the path for medicines that improve memory retention in both healthy and impaired brain systems.

The study was published last week in the journal Neuron. “We concluded that there is a direct connection between the vagus nerve, the cholinergic system that regulates certain aspects of brain function, and motor cortex neurons that are essential in learning new skills,” said Cristin Welle, PhD, senior author of the paper and the vice chair of research for the Department of Neurosurgery at the University of Colorado School of Medicine. “This could provide hope to patients with a variety of motor and cognitive impairments, and someday help healthy individuals learn new skills faster.”

Researchers taught healthy mice a demanding activity to determine whether it may aid boost learning. They noticed that activating the vagus nerve throughout the procedure aided them in learning the task considerably faster and performing at a higher level. This demonstrated that stimulating the vagus nerve can improve learning in a healthy neurological system.

The vagus nerve is important because it controls internal organ processes such as digestion, heart rhythm, and respiration. It also aids in the regulation of reflex activities such as coughing, swallowing, and sneezing.

The study also discovered a direct link between the vagus nerve and the cholinergic system, which is critical for learning and attention. Researchers were able to see the neurons that govern learning engaged inside the cholinergic system every time the vagus nerve was stimulated. Damage to this system has been related to Alzheimer’s, Parkinson’s, and other motor and cognitive disorders. Welle believes that now that this link has been demonstrated in healthy nerve systems, it might lead to improved treatment choices for people whose systems have been damaged.

“The idea of being able to move the brain into a state where it’s able to learn new things is important for any disorders that have motor or cognitive impairments,” she said. “Our hope is that vagus nerve stimulation can be paired with ongoing rehabilitation in disorders for patients who are recovering from a stroke, traumatic brain injury, PTSD or a number of other conditions.”

In addition to the study, Welle and her colleagues have filed for funding to utilise a non-invasive device to stimulate the vagus nerve to treat individuals with multiple sclerosis who have acquired mobility difficulties. She also hopes that this technology will someday help healthy individuals acquire new skills more quickly.

“I think there’s a huge untapped potential for using vagus nerve stimulation to help the brain heal itself,” she said. “By continuing to investigate it, we can ultimately optimize patient recovery and open new doors for learning.”