Anger researcher Ryan Martin draws from a career studying what makes people mad to explain some of the cognitive processes behind anger -- and why a healthy dose of it can actually be useful. "Your anger exists in you ... because it offered your ancestors, both human and nonhuman, an evolutionary advantage," he says. "[It's] a powerful and healthy force in your life."
Many of us will experience some kind of trauma during our lifetime. Sometimes, we escape with no long-term effects. But for millions of people, those experiences linger, causing symptoms like flashbacks, nightmares, and negative thoughts that interfere with everyday life. Joelle Rabow Maletis details the science behind post-traumatic stress disorder, or PTSD.