Vagus nerve stimulation shows promise as a way to counter Alzheimer’s disease- and age-related memory loss

The vagus nerve, which carries information between the brain and heart, lungs and other organs, might regulate the activity of a tiny brain region called the locus coeruleus. Sebastian Kaulitzki/Science Photo Library via Getty Images

Most people think of Alzheimer’s disease as an illness of aging. But in fact, the brain changes that characterize it begin much earlier – sometime around the third decade of life.

In the earliest of these changes, a tangled version of a protein called tau starts building up in a tiny region deep in the brain involved in sleep, attention and alertness, called the locus coeruleus. Tau later spreads to the rest of the brain.