Researchers have identified a new personality type. Chances are you’ve had it

Whether it’s the ancient Greeks trying to divine one’s character from the stars, or modern surveys that purport to tell you what type of person you are, experts have struggled to come up with a trustworthy personality test. Now, the largest study of its kind suggests people reliably shake out into four major personality types—including a brand new one that, surprisingly, most people will possess at some point during their life.

“I think this is an extremely impressive study,” says Richard Robins, a social psychologist at the University of California, Davis, who has been researching human personality for decades. Until now, “The field was plagued by relatively small samples and the use of different methods and data sets,” he says. “We needed somebody to come along and clean things up.”

After decades of tweaking and standardizing their methods, most Western psychologists generally agree that humans exhibit five major personality traits: neuroticism, extraversion, openness, agreeableness, and conscientiousness. Depending on the combination, these traits spawn three broad personality types: resilient, overcontrolled, and undercontrolled. Resilient people tend to be able to handle their emotions, get along with others, and bounce back from life’s adversities; “overcontrolled” individuals are aloof or shy, keeping their feelings hidden; and “undercontrolled” people can be emotionally impulsive, sometimes even acting out aggressively