Unity and interconnectedness from Dextromethorphan

Unity and interconnectedness is the experience of one's sense of self becoming temporarily expanded to feel as though it encompasses a wider array of concepts, entities, or phenomena than it normally does. While a person typically identifies exclusively with their ego or a combination of their ego and physical body, during this state the boundaries of identity shift to also include the external environment, other people, nature, the cosmos, or the totality of existence itself. This produces a profound felt sense of oneness that is often described as one of the most meaningful experiences of a person's life.

At its mildest, the effect manifests as an enhanced sense of empathy and connection with other people or one's surroundings. One may feel an unusual kinship with strangers, a deep appreciation for the interconnected web of life, or a sense that the boundaries between self and other are thinner than usually perceived. These feelings are emotionally warm and often accompanied by a sense of compassion, love, and belonging.

As the effect intensifies, the sense of interconnection deepens and broadens. One may begin to feel genuinely identified with other people present, experiencing their emotions and perspectives as though they were one's own. The distinction between self and environment may blur, with the person feeling as though they are an inseparable part of the landscape, the room, or the natural world around them. There may be a powerful intuition that all things are fundamentally connected at a level deeper than ordinary perception reveals.

At its peak, unity and interconnectedness can culminate in a complete dissolution of the boundary between self and other, producing what is sometimes described as a mystical or transcendent experience. The person may feel that they are literally identical with the universe, that all separation is an illusion, and that a single consciousness underlies all of reality. This state is frequently accompanied by feelings of profound peace, awe, sacredness, and ineffability — the sense that the experience is beyond what language can adequately describe.

Unity and interconnectedness is most commonly induced under the influence of moderate to heavy dosages of psychedelic compounds such as LSD, psilocybin, DMT, ayahuasca, and mescaline, as well as dissociatives like ketamine at certain doses. It is a defining feature of what researchers call the "complete mystical experience" and is closely associated with ego dissolution, spirituality intensification, and feelings of eternal or infinite existence. Research has shown that experiences of unity are among the strongest predictors of lasting positive psychological change following psychedelic use.