Psilocybin in the context of "Serotonin"

Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary mental states (known as psychedelic experiences or "trips") and a perceived "expansion of consciousness". Also referred to as classic hallucinogens or serotonergic hallucinogens, the term psychedelic is sometimes used more broadly to include various other types of hallucinogens as well, such as those which are atypical or adjacent to psychedelia like salvia and MDMA, respectively.

Classic psychedelics generally cause specific psychological, visual, and auditory changes, and oftentimes a substantially altered state of consciousness. They have had the largest influence on science and culture, and include mescaline, LSD, psilocybin, and DMT. There are a large number of both naturally occurring and synthetic serotonergic psychedelics.

Entheogens are psychoactive substances used in spiritual, religious, recreational, therapeutic, and experimental contexts to induce altered states of consciousness. While the term itself emphasizes ritual and sacred applications, the same substances are also frequently employed recreationally—sometimes in ways that diverge from or disregard traditional protocols. Hallucinogens such as the psilocybin found in so-called "magic" mushrooms have been used in sacred contexts since ancient times. Derived from a term meaning "generating the divine from within", entheogens are, in religious and shamanic contexts, intentionally employed in the attempt to facilitate experiences of transcendence, healing, divination, and mystical insight.

Entheogens have been used in religious rituals in the belief they aid personal spiritual development. Anthropological study has established that entheogens are used for religious, magical, shamanic, or spiritual purposes in many parts of the world. Civilizations such as the Maya and Aztecs used psilocybin mushrooms, peyote, and morning glory seeds in ceremonies meant to connect with deities and perform healing. They have traditionally been used to supplement diverse practices, such as transcendence, including healing, divination, meditation, yoga, sensory deprivation, asceticism, prayer, trance, rituals, chanting, imitation of sounds, hymns like peyote songs, drumming, and ecstatic dance.

Hallucinogens, also known as psychedelics, entheogens, or historically as psychotomimetics, are a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Hallucinogens are often categorized as either being psychedelics, dissociatives, or deliriants, but not all hallucinogens fall into these three classes.

Examples of hallucinogens include psychedelics or serotonin 5-HT_2A receptor agonists like LSD, psilocybin, mescaline, and DMT; dissociatives or NMDA receptor antagonists like ketamine, PCP, DXM, and nitrous oxide; deliriants or antimuscarinics like scopolamine and diphenhydramine; cannabinoids or cannabinoid CB₁ receptor agonists like THC, nabilone, and JWH-018; κ-opioid receptor agonists like salvinorin A and pentazocine; GABA_A receptor agonists like muscimol and gaboxadol; oneirogens like ibogaine and harmaline; and others like nutmeg, carbogen, glaucine, and hallucinogenic bolete mushrooms.

A psychoactive drug, psychopharmaceutical, mind-altering drug, consciousness-altering drug, psychoactive substance, or psychotropic substance is a chemical substance that alters psychological functioning by modulating central nervous system (CNS) activity. Psychoactive and psychotropic drugs both affect the brain, with psychotropics sometimes referring to psychiatric drugs or high-abuse substances, while “drug” can have negative connotations. Novel psychoactive substances are designer drugs made to mimic illegal ones and bypass laws.

Psychoactive drug use dates back to prehistory for medicinal and consciousness-altering purposes, with evidence of widespread cultural use. Many animals intentionally consume psychoactive substances, and some traditional legends suggest animals first introduced humans to their use. Psychoactive substances are used across cultures for purposes ranging from medicinal and therapeutic treatment of mental disorders and pain, to performance enhancement. Their effects are influenced by the drug itself, the environment, and individual factors. Psychoactive drugs are categorized by their pharmacological effects into types such as anxiolytics (reduce anxiety), empathogen–entactogens (enhance empathy), stimulants (increase CNS activity), depressants (decrease CNS activity), and hallucinogens (alter perception and emotions). Psychoactive drugs are administered through various routes—including oral ingestion, injection, rectal use, and inhalation—with the method and efficiency differing by drug.

Psychedelia usually refers to a style or aesthetic that is resembled in the psychedelic subculture of the 1960s and the psychedelic experience produced by certain psychoactive substances. This includes psychedelic art, psychedelic music and style of dress during that era. This was primarily generated by people who used psychedelic drugs such as LSD, mescaline (found in peyote) and psilocybin (found in magic mushrooms) and also non-users who were participants and aficionados of this subculture. Psychedelic art and music typically recreate or reflect the experience of altered consciousness. Psychedelic art uses highly distorted, surreal visuals, bright colors and full spectrums and animation (including cartoons) to evoke, convey, or enhance the psychedelic experience.

Psychedelic music uses distorted electric guitar, Indian music elements such as the sitar and tabla, electronic effects, sound effects and reverb, and elaborate studio effects, such as playing tapes backwards or panning the music from one side to another.