Why Do People Have Painful Feelings? An Evolutionary Tale of Misery and Woe

Humans share with other animals the capacity to feel many different kinds of pain. Evolutionary theory proposes that all painful feelings evolved to motivate the organism to avoid problems or stressors in their environment. I apply this perspective to several types of aversive feelings in humans and other organisms. First, squid that have been physically injured show a long-term motivational change that protects them from further injury. Second, rats that have been exposed to repeated, inescapable shock do not appear to have lost the motivation to avoid the shocks. Rather, they appear to be motivated to switch strategies for avoiding the shocks—switching from a quick, associational processing strategy to a slow, attentionally demanding processing strategy. In humans, the field of psychiatry considers depression to be a state in which motivation is lacking. However, the emotional responses of physicians who become depressed after making a serious medical error challenge this view. The aversive feelings they experience appear to motivate them to make constructive changes to their practice that reduce the chances of making similar errors in the future. Finally, I review evidence that anxiety-related feelings motivate people to adopt a better-safe-than-sorry approach to potential threats.