Self-reflection, the psychological activity of thinking about one’s own characteristics, has long been the focus of art (as shown here in Picasso’s Girl Before a Mirror). In twentieth-century personality theory, it was the focus of psychology, as personality theorists came to view self-reflection as a central personality process. In the twenty-first century, self-reflection is also targeted by neuroscientists, who search for brain regions that give people the power to reflect upon themselves.