Energy psychology is an approach to psychotherapy and self-help that combines conventional psychological procedures with techniques adapted from ancient healing and spiritual traditions such as meditation, yoga, and acupuncture. It is distinguished for its ability to—with unusual speed and precision—produce changes in the brain chemistry that underlies a wide range of psychological problems and goals. Studies have shown it to be effective in treating anxiety, depression, posttraumatic stress disorder, physical pain, and weight control as well as in helping heal physical illnesses and optimize the performances of athletes and others striving for their personal best.