The healing elements of the movement are difficult to classify given that a variety of terms are used, with some New Age authors using different terms to refer to the same trends, while others use the same term to refer to different things. However, Hanegraaff developed a set of categories into which the forms of New Age healing could be roughly categorised. The first of these was the Human Potential Movement, which argues that contemporary Western society suppresses much human potential, and accordingly professes to offer a path through which individuals can access those parts of themselves that they have alienated and suppressed, thus enabling them to reach their full potential and live a meaningful life. Hanegraaff described transpersonal psychology as the "theoretical wing" of this Human Potential Movement; in contrast to other schools of psychological thought, transpersonal psychology takes religious and mystical experiences seriously by exploring the uses of altered states of consciousness. Closely connected to this is the shamanic consciousness current, which argues that the shaman was a specialist in altered states of consciousness and seeks to adopt and imitate traditional shamanic techniques as a form of personal healing and growth.