Most mammals play, but they do so in a dangerous world. The dynamic relationship between the stresses created by their world and the activity of play helps to explain the evolution of play in mammals, as the author demonstrates in evidence garnered from experiments that introduce elements of fear to rats at play. The author describes the resulting…

Jaak Panksepp, known best for his work on animal emotions and coining the term "affective neuroscience," investigates the primary processes of brain and mind that enable and drive emotion. As an undergraduate, he briefly considered a career in electrical engineering but turned instead to psychology, which led to a 1969 University of…

Scholars interested in play in humans should take note of the growing literature on play in other species, especially in light of the application of evolutionary approaches to virtually all areas of psychology. Although most research on animal play deals with mammals--particularly rodents, carnivores, and primates--studies have recorded play of…

Stuart L. Brown is founder of the National Institute for Play, a California-based, not-for-profit organization dedicated to the notion that play can help transform the lives of individuals, families, schools, and organizations. Trained in general and internal medicine, psychiatry, and clinical research, Brown was a physician in the United States…