Loneliness Can Change the Brain

Everyone feels lonely from time to time — after, say, a move to a new school or city, when a child leaves for college, or following the loss of a spouse.

Some people, though, experience loneliness not just transiently but chronically. It becomes “a personality trait, something that’s pretty sticky,” said Dr. Ellen Lee, an associate professor of psychiatry at the University of California, San Diego. These individuals seem to have “this persistent emotion that then shapes their behavior.”

Research is mounting that this type of entrenched loneliness is bad for our health and can even change our brains, raising the risk for neurodegenerative diseases. Here’s what experts know about how chronic loneliness affects the brain, and some strategies to address it.

How does loneliness change the brain?

Humans evolved to be social creatures probably because, for our ancient ancestors, being alone could be dangerous and reduce the odds of survival. Experts think loneliness may have emerged as a unique type of stress signal to prompt us to seek companionship.

With chronic loneliness, that stress response gets stuck and becomes disadvantageous — similar to the way in which anxiety can shift a helpful fear response to a maladaptive mental illness.

“Small, transient episodes of loneliness really motivate people to then seek out social connection,” said Anna Finley, a postdoctoral research fellow at the Institute on Aging at the University of Wisconsin-Madison. “But in chronic episodes of loneliness, that seems to kind of backfire” because people become especially attuned to social threats or signals of exclusion, which can then make it scary or unpleasant for them to interact with others.