The vagus nerve is a long wandering nerve that stems from the brain and is responsible for connecting it to the body's vital organs. It can have a significant impact on mental health, affecting mood, anxiety levels, and depression.
Bioengineer, Karl Deisseroth, is working on creating small light diodes that can stimulate nerves without the need for viruses, which will allow for more specific stimulation of specific neurons in the brain. This could be a significant improvement from the effects of current drugs that can bring unwanted side effects.