Ecopsychology studies the relationship between human beings and the natural world through ecological and psychological principles. The field seeks to develop and understand ways of expanding the emotional connection between individuals and the natural world, thereby assisting individuals with developing sustainable lifestyles and remedying alienation from nature. Theodore Roszak is credited with coining the term in his 1992 book, The Voice of the Earth, although a group of psychologists and environmentalists in Berkeley, including Mary Gomes and Allen Kanner, were independently using the term to describe their own work at the same time. Roszak, Gomes and Kanner later expanded the idea in the 1995 anthology Ecopsychology. Two other books were especially formative for the field, Paul Shepard's 1982 volume, "Nature and Madness," which explored the effect that our ever-diminishing engagement with wild nature had upon human psychological development, and philosopher David Abram's The Spell of the Sensuous: Perception and Language in a More-than-Human World, published in 1996. The latter was the first widely read book to bring phenomenology to bear on ecological and ecopsychological issues, examining in detail the earthly dimensions of sensory experience, and disclosing the historical effect of formal writing systems upon the human experience of nature's agency, voice, and interiority.
A central premise of ecopsychology is that while today the human mind is affected and shaped by the modern social world, its deep structure is inevitably adapted to, and informed by, the more-than-human natural environment in which it evolved. According to the biophilia hypothesis of biologist E.O. Wilson, human beings have an innate instinct to connect emotionally with nature, particularly the aspects of nature that recall what evolutionary psychologists have termed the environment of evolutionary adaptiveness, the natural conditions that the human species evolved to inhabit.
The field of ecopsychology extends beyond the conventional purview of psychology, which had traditionally considered the psyche to be a matter of relevance to humans alone. Ecopsychology examines why people continue environmentally damaging behaviour, and to develop methods of positive motivation for adopting sustainable practices. Evidence suggests that many environmentally damaging behaviours are addictive at some level, and thus are more effectively addressed through positive emotional fulfillment rather than by inflicting shame. Other names used to refer to ecopsychology include depth ecology, Gaia psychology, psychoecology, ecotherapy, environmental psychology, green psychology, transpersonal ecology, global therapy, green therapy, Earth-centered therapy, reearthing, nature-based psychotherapy, shamanic counselling, ecosophy and sylvan therapy.