One of the most damaging fallacies about psychopathy—in fiction, in the news, and in some of the old scientific literature—is that it is a permanent, unchanging condition. This idea reinforces the compelling good-versus-evil trope, but the latest research tells a quite different story.

Traits of psychopathy naturally decrease over time for many young people, starting in late adolescence into adulthood. Samuel Hawes, a psychologist at Florida International University, and his collaborators tracked more than 1,000 individuals from childhood to adulthood, repeatedly measuring their traits of psychopathy. Although a small group showed persistently high levels of psychopathic traits, more than half of the boys who initially had high levels of those traits trended downward over time and no longer presented with them later in adolescence.

With proper intervention, the prospects for improvement get better. We are finding that youth with traits of psychopathy and adults with psychopathy can change and respond to treatments that are tailored to their needs. Several studies have documented the effectiveness of specific treatments designed to help youth learn to identify and respond to emotions. Parent training that focuses on enhancing the emotional warmth of the caregiver and helping youth identify emotions seems to reduce symptoms and problematic behavior.