A

2C-B (4-Bromo-2,5-dimethoxyphenethylamine) — Synthetic phenethylamine psychedelic synthesized by Alexander Shulgin; known for tactile enhancement and relatively clear headspace. Phenethylamines Alexander Shulgin

2C-I, 2C-E, 2C-T-2, 2C-T-7 — Series of synthetic phenethylamine psychedelics from Shulgin’s research; varying in potency and character. Phenethylamines Alexander Shulgin

4-AcO-DMT (Psilacetin) — Synthetic tryptamine structurally similar to psilocybin; likely metabolizes to psilocin in the body.

4-HO-MET (Metocin) — Synthetic tryptamine analog of psilocin with lighter mental effects and pronounced visuals. Tryptamines Alexander Shulgin

5-HT receptor family — Serotonin receptor subtypes (5-HT1A through 5-HT7) with varying roles in psychedelic pharmacology.

5-HT2A receptor — Primary serotonin receptor subtype responsible for classical psychedelic effects; G-protein coupled receptor.

5-HT2B receptor — Serotonin receptor implicated in cardiac valvulopathy with chronic activation; safety concern for some psychedelics.

5-HT2C receptor — Serotonin receptor contributing to anxiety, appetite, and some psychedelic effects.

5-MeO-DALT — Synthetic tryptamine with unique pharmacology; less visual than other tryptamines. Tryptamines Alexander Shulgin

5-MeO-DiPT (Foxy) — Synthetic tryptamine known for auditory distortions and tactile enhancement. Tryptamines Alexander Shulgin

5-MeO-DMT — Potent naturally occurring tryptamine; found in Bufo alvarius/Incilius alvarius toad secretions and various plants; primarily non-visual.

5-MeO-MiPT (Moxy) — Synthetic tryptamine with empathogenic qualities alongside psychedelic effects. Tryptamines Alexander Shulgin

Absorption — Process by which a substance enters systemic circulation; varies by route of administration.

Acacia species — Australian trees containing DMT and other tryptamines in bark and leaves; used in “Aussie-huasca.”

Active dose — Minimum amount of a substance required to produce noticeable psychoactive effects.

Acute tolerance — Immediate reduction in drug effects during a single session or with repeated dosing.

Addiction potential — Likelihood of developing dependence; generally low for classical psychedelics.

Afterglow — Positive mood and cognitive effects persisting days to weeks after a psychedelic experience.

Agonist — Molecule that activates a receptor; psychedelics are primarily 5-HT2A agonists or partial agonists.

AL-LAD — Lysergamide analog of LSD with shorter duration and more visual character. LSD analogues

Aldous Huxley — British author of “The Doors of Perception” (1954) and “Heaven and Hell” (1956); coined term “psychedelic.”

Alexander “Sasha” Shulgin — American chemist who synthesized and tested hundreds of psychedelics; author of Phenethylamines and Tryptamines. Alexander Shulgin

Allosteric modulation — Indirect receptor regulation by binding at sites other than the primary binding site.

Amanita muscaria — Psychoactive mushroom containing muscimol and ibotenic acid; distinct from psilocybin mushrooms.

Amanda Feilding — British drug policy reformer and founder of the Beckley Foundation.

AMT (α-Methyltryptamine) — Long-acting synthetic tryptamine with stimulant and psychedelic properties. Tryptamines

Anadenanthera colubrina/peregrina — South American trees whose seeds contain DMT, 5-MeO-DMT, and bufotenine.

Analog (drug) — Chemical compound structurally similar to another; basis for the Federal Analog Act.

Anandamide — Endogenous cannabinoid neurotransmitter; name means “bliss molecule” in Sanskrit.

Ann Shulgin — Co-author with Alexander Shulgin; pioneered lay therapy with MDMA and psychedelics.

Antagonist — Molecule that blocks receptor activation by other compounds.

Anxiolytic — Substance or effect that reduces anxiety.

Apoptosis — Programmed cell death; some psychedelics show anti-apoptotic properties.

Argyreia nervosa (Hawaiian Baby Woodrose) — Seeds containing LSA and other ergot alkaloids.

Ayahuasca — Traditional Amazonian brew combining DMT-containing plants with MAO-inhibiting B. caapi vine.

Ayahuasca churches — Religious organizations using ayahuasca sacramentally (Santo Daime, UDV, Barquinha).

B

Bad trip — Difficult or challenging psychedelic experience characterized by anxiety, fear, or distressing content. Perspectives and Framing

Banisteriopsis caapi — “Vine of the soul”; contains β-carboline MAO inhibitors enabling oral DMT activity. Ayahuasca

Baseline — Normal psychological state before substance administration.

BDNF (Brain-Derived Neurotrophic Factor) — Protein promoting neuroplasticity; increased by some psychedelics.

Beckley Foundation — UK-based think tank researching psychedelics and drug policy reform.

Behavioral tolerance — Learned compensation for drug effects through practice.

Bioavailability — Proportion of administered drug reaching systemic circulation.

Biogenetic structuralism — Theory linking neurobiology to religious/mystical experiences.

Blood-brain barrier — Selective membrane preventing most substances from entering the brain.

Breakthrough dose — Amount of DMT (typically 25-50mg vaporized) producing complete immersion in visionary space. DMT

Breathwork — Non-pharmacological technique producing altered states; often used in integration.

Bufo alvarius (Incilius alvarius) — Sonoran Desert toad producing 5-MeO-DMT and bufotenine in skin secretions. 5-MeO-DMT

Bufotenine (5-HO-DMT) — Tryptamine found in toads and plants; disputed psychoactivity when pure.

C

Candyflipping — Combining LSD and MDMA for synergistic effects.

Cannabis — Plant containing THC and CBD; often combined with psychedelics despite interaction risks.

Carhart-Harris, Robin — British neuroscientist; developed REBUS model and entropic brain hypothesis.

Catalytic dose — Sub-perceptual amount of a substance used to facilitate therapy or meditation. Perspectives and Framing

Changa — Smokeable blend of DMT-enhanced herbs with MAO inhibitors for extended duration.

Charles Grob — American psychiatrist conducting psilocybin studies for anxiety in cancer patients.

Chemical imbalance theory — Disputed model of mental illness; challenged by psychedelic research. DMT

Chromatography — Laboratory technique for separating and identifying compounds.

Claudio Naranjo — Chilean psychiatrist pioneering psychedelic therapy with ibogaine and MDA.

Closed-eye visuals (CEVs) — Visual phenomena experienced with eyes closed during psychedelic states.

Cognitive flexibility — Mental ability to adapt thinking; enhanced by psychedelics.

Collective unconscious — Jungian concept often referenced in psychedelic discourse.

Come-up — Initial phase of drug effects manifesting; often accompanied by anxiety.

Consciousness — Subjective awareness; central mystery in psychedelic research.

Controlled Substances Act — 1970 U.S. law placing most psychedelics in Schedule I. DMT LSD Timothy Leary

Cross-tolerance — Reduced response to one drug due to tolerance from another.

Cytochrome P450 — Liver enzyme family metabolizing many drugs including psychedelics.

D

David Nichols — American pharmacologist; founded Heffter Research Institute; coined “entactogen.”

David Nutt — British neuropsychopharmacologist advocating evidence-based drug policy.

Decriminalization — Removing criminal penalties for personal possession/use.

Default Mode Network (DMN) — Brain network associated with self-referential processing; disrupted by psychedelics.

Dennis McKenna — Ethnopharmacologist and brother of Terence McKenna; expert on ayahuasca and plant hallucinogens.

Depersonalization — Loss of sense of personal identity; related to ego dissolution.

Derealization — Feeling that external world is unreal; can occur with high doses.

DET (Diethyltryptamine) — Synthetic tryptamine similar to DMT but orally active. Tryptamines

Dimethyltryptamine (DMT) — “The spirit molecule”; endogenous psychedelic tryptamine.

DiPT (Diisopropyltryptamine) — Unique tryptamine primarily causing auditory distortions. Tryptamines

Dissociation — Detachment from physical/emotional experience; primary effect of Ketamine, PCP.

Distribution (pharmacokinetics) — Movement of drug throughout body tissues.

DOM (STP) — Long-acting psychedelic amphetamine; caused overdoses in 1960s San Francisco.

Dopamine — Neurotransmitter involved in reward, motivation; indirectly affected by psychedelics.

Dose-response curve — Graph showing relationship between drug amount and effect magnitude.

Double-blind — Research design where neither participants nor researchers know who receives drug vs placebo.

DPT (Dipropyltryptamine) — Synthetic tryptamine used by Temple of the True Inner Light. Tryptamines

Drug scheduling — Legal classification system for controlled substances.

E

Ecstasy — Street name for MDMA; often adulterated with other substances.

Effective dose (ED50) — Amount producing desired effect in 50% of population.

Ego death/dissolution — Complete loss of subjective self-identity.

Elimination half-life — Time for drug concentration to decrease by 50%.

Empathogen/Entactogen — Substances increasing emotional openness (MDMA, MDA).

Endogenous — Naturally produced within the body.

Entheogen — “Generating the divine within”; spiritual context for psychedelics. Perspectives and Framing

Entity contact — Encounters with seemingly autonomous beings during psychedelic experiences.

Entropic brain hypothesis — Theory that psychedelics increase neural entropy/complexity.

Enzyme — Protein catalyzing biochemical reactions; crucial for drug metabolism.

Epigenetics — Gene expression changes without DNA sequence alteration; potentially affected by psychedelics.

Ergot alkaloids — Fungal compounds; precursors to LSD; found in morning glory seeds.

ETH-LAD — Lysergamide with unique visual character; more potent than LSD by weight. LSD analogues

Ethnobotany — Study of traditional plant use by indigenous cultures. Dennis McKenna

Euphoria — Intense pleasure and well-being; common with MDMA, some psychedelics.

F

First-pass metabolism — Drug breakdown in liver before reaching systemic circulation. LSD analogues

Flashback — Brief recurrence of psychedelic effects without recent use.

Flow state — Optimal experience characterized by complete absorption; sometimes induced by psychedelics.

Foxy (5-MeO-DiPT) — Synthetic tryptamine with unique auditory effects. Tryptamines

Frances Vaughan — Transpersonal psychologist; early psychedelic therapy researcher.

Functional selectivity — Ability of drugs to selectively activate specific receptor signaling pathways.

G

GABA — Primary inhibitory neurotransmitter; modulated by some psychedelics.

Gillin, J. Christian — Lead author of the 1976 NIH review “The Psychedelic Model of Schizophrenia (1976).”

Glutamate — Primary excitatory neurotransmitter; NMDA antagonists produce dissociation.

Gordon Wasson — Banker/mycologist who publicized psilocybin mushrooms in Life magazine (1957).

Grof, Stanislav — Czech psychiatrist developing psychedelic therapy and holotropic breathwork.

H

Half-life — Time for drug concentration to reduce by 50%.

Hallucinogen — Outdated term for psychedelics; implies false perceptions. Perspectives and Framing

Hallucinogen Persisting Perception Disorder (HPPD) — Persistent visual disturbances following psychedelic use.

Hamilton Morris — Journalist/chemist documenting psychoactive substances in “Hamilton’s Pharmacopeia.”

Harmala alkaloids — β-carbolines (harmine, harmaline, THH) inhibiting MAO.

Harm reduction — Pragmatic approach minimizing drug-related harm without requiring abstinence.

Head space — Cognitive/emotional aspects of psychedelic experience. Perspectives and Framing Set, Setting and the Substance

Heffter Research Institute — Organization funding psychedelic research since 1993.

Heroic doseTerence McKenna’s term for 5+ grams dried psilocybin mushrooms.

Hippie flip — Combining Psilocybin mushrooms with MDMA.

Albert Hofmann — Swiss chemist who discovered LSD (1938) and isolated Psilocybin (1958).

Holotropic breathwork — Stanislav Grof’s technique inducing non-ordinary states without drugs.

Humphry Osmond — British psychiatrist who coined “psychedelic” in correspondence with Aldous Huxley.

HyperspaceDMT users’ term for visionary realm accessed during breakthrough experiences.

I

Iboga — West African shrub containing ibogaine; used in Bwiti tradition. Ibogain

Ibogaine — Indole alkaloid with anti-addictive properties; produces waking dream state.

Imperial College London — Leading institution for psychedelic neuroimaging research.

INMT (Indolethylamine N-Methyltransferase) — Enzyme methylating tryptamine to form DMT.

Integration — Processing and incorporating psychedelic experiences into daily life. Perspectives and Framing

Intention setting — Establishing purpose before psychedelic experience. Perspectives and Framing

Intramuscular (IM) — Injection into muscle tissue; used in some research.

Intravenous (IV) — Direct injection into vein; produces rapid onset.

Ipomoea tricolor — Morning glory species containing LSA. LSD analogues

J

James Fadiman — Psychologist researching psychedelics since 1960s; popularized microdosing.

Jedi flip — Combining LSD, Psilocybin, and MDMA.

Johns Hopkins — University conducting landmark psilocybin research since 2000s.

Jung, Carl — Psychologist whose concepts (shadow, individuation) inform psychedelic therapy.

K

K-hole — Deep dissociative state from high-dose Ketamine.

Kappa opioid receptor — Target of Salvinorin A producing unique dissociative effects.

Katherine MacLean — Psychologist researching personality changes from psilocybin.

Ken Kesey — Author who popularized LSD through “Acid Tests” with Merry Pranksters.

Ketamine — Dissociative anesthetic with rapid antidepressant effects; NMDA antagonist.

Kitty flipping — Combining Ketamine with MDMA.

L

Language distortion — Difficulty forming coherent speech at high doses.

Laura HuxleyAldous Huxley’s wife; administered LSD on his deathbed.

LD50 (Lethal Dose 50%) — Amount causing death in 50% of test subjects.

Timothy Leary — Harvard psychologist turned LSD evangelist; “Turn on, tune in, drop out.”

Leo Zeff — “Secret Chief”; underground psychedelic therapist training many practitioners.

Lilly, John C. — Neuroscientist exploring consciousness with isolation tanks and Ketamine.

Lophophora williamsiiPeyote Cactus containing Mescaline; used ceremonially by Native Americans.

LSA (Lysergic Acid Amide) — Natural ergot alkaloid in morning glory and Hawaiian baby woodrose seeds.

LSD (Lysergic Acid Diethylamide) — Semi-synthetic ergot derivative; most potent common psychedelic.

LSZ — Lysergamide analog with unique properties; Shulgin called it “Diazedine.” LSD analogues Alexander Shulgin

M

Machine elvesTerence McKenna’s term for entities encountered on DMT.

MAO (Monoamine Oxidase) — Enzyme breaking down monoamines; inhibited to allow oral DMT activity. Ayahuasca

MAOI — Monoamine oxidase inhibitor; pharmaceutical or natural (harmala alkaloids). Ayahuasca

MAPS (Multidisciplinary Association for Psychedelic Studies) — Organization founded by Rick Doblin advancing psychedelic research.

María Sabina — Mazatec curandera who introduced psilocybin mushrooms to Westerners.

Matthew Johnson — Johns Hopkins researcher studying psilocybin for addiction.

MDA — “Sass”; empathogenic amphetamine; parent compound of MDMA.

MDMA — 3,4-Methylenedioxymethamphetamine; empathogen used in PTSD therapy.

Mescaline — Phenethylamine psychedelic from Peyote Cactus and San Pedro cacti.

Metabolism — Biochemical modification of substances in the body.

Microdosing — Taking sub-perceptual doses (typically 5-20% of active dose) for subtle benefits.

Mimosa hostilis/tenuiflora — Root bark containing ~1% DMT; used in jurema and extraction. The DMT Nexus

Mind manifesting — Literal meaning of “psychedelic” from Greek psyche (mind) and delos (manifest). Perspectives and Framing

MK-ULTRA — CIA program experimenting with LSD for mind control (1950s-1970s).

Mystical experience — Profound spiritual state; measured by MEQ-30 questionnaire in research. Perspectives and Framing

N

Native American Church — Religious organization with legal peyote use. Peyote Cactus

NBOMe series — Potent phenethylamine psychedelics; associated with fatalities.

Neurogenesis — Formation of new neurons; potentially stimulated by psychedelics. Science & Research

Neuroplasticity — Brain’s ability to reorganize; enhanced by psychedelics. Science & Research

Neurotransmitter — Chemical messenger between neurons.

Nexus, The DMT — Online forum dedicated to DMT chemistry, harm reduction, and experience reports. The DMT Nexus

Nexus flip — Combining 2C-B with MDMA. Phenethylamines

Nicholas Sand — Underground chemist who synthesized massive quantities of LSD.

Nitrous oxide — Dissociative gas producing brief altered state; often combined with psychedelics.

NMDA receptor — Glutamate receptor blocked by dissociatives.

O

Oceanic boundlessness — Feeling of unity with universe; measured by 5D-ASC scale.

Oliver Sacks — Neurologist who wrote about his psychedelic experiences.

Open-eye visuals (OEVs) — Visual distortions with eyes open.

Openness — Personality trait increased by psilocybin in Johns Hopkins study.

Orange Sunshine — Famous LSD variety from 1960s-70s.

Owsley Stanley — “Bear”; legendary LSD chemist supplying 1960s counterculture.

P

P450 enzymes — Cytochrome P450 family metabolizing many drugs.

Pahnke, Walter — Conducted Good Friday Experiment with psilocybin at Harvard. LSD Ram Dass

Partial agonist — Compound producing submaximal receptor activation.

Paul Stamets — Mycologist advocating fungal solutions and psilocybin benefits.

PCP (Phencyclidine) — Dissociative anesthetic; NMDA antagonist with stimulant properties.

Peak experience — Abraham Maslow’s term for transcendent states.

Peganum harmala (Syrian rue) — Plant containing harmala alkaloids; Ayahuasca analog.

Peter Gasser — Swiss psychiatrist conducting LSD-assisted psychotherapy trials.

Peyote — Mescaline-containing cactus sacred to Native Americans. Peyote Cactus

Pharmacodynamics — Drug effects on the body via receptor interactions.

Pharmacokinetics — Drug absorption, distribution, metabolism, excretion (ADME).

Pharmahuasca — Ayahuasca analog using pure/synthetic compounds. Ayahuasca Other Compounds

Phenethylamine — Chemical class including mescaline, MDMA, 2C series. Phenethylamines

Phenethylamines — “Phenethylamines I Have Known And Loved”; Shulgin’s phenethylamine compendium. Alexander Shulgin

Pineal gland — Brain structure mystically linked to consciousness; produces melatonin, possibly DMT.

Placebo — Inactive substance used as control in research. Perspectives and Framing

Prodrug — Inactive compound metabolized into active form (e.g., psilocybin→psilocin).

Psilocin — Active metabolite of Psilocybin; 4-HO-DMT. Tryptamines

Psilocybe — Genus containing ~200 psilocybin mushroom species.

Psilocybin — Prodrug in magic mushrooms; converted to psilocin.

Psychedelic — “Mind-manifesting”; substances producing altered states via 5-HT2A agonism. Perspectives and Framing

Psychedelic renaissance — Revival of psychedelic research since ~2000.

Psychedelic therapy — Using psychedelics as adjuncts to psychotherapy.

Psycholytic therapy — Low-dose psychedelic therapy style from Europe.

Psychonautics — Exploration of consciousness through altered states.

Psychotomimetic — “Psychosis-mimicking”; outdated term for psychedelics.

PTSD — Post-traumatic stress disorder; treated with MDMA therapy.

Q

Qualia — Subjective conscious experiences; altered by psychedelics.

R

Ralph Metzner — Psychologist; co-author of “The Psychedelic Experience” with Leary and Alpert. Ram Dass Timothy Leary

Ram Dass(Richard Alpert) — Harvard psychologist turned spiritual teacher after psychedelics.

Randomized controlled trial (RCT) — Gold standard research design.

Rapid tolerance — Quick development of reduced effects with repeated use.

REBUS — “Relaxed Beliefs Under Psychedelics”; Carhart-Harris model.

Receptor — Protein that binds molecules to trigger cellular response.

Receptor binding profile — Pattern of receptor affinities determining drug effects.

Research chemicals — Novel psychoactive substances with limited safety data.

Reverse tolerance — Increased sensitivity with repeated use; reported with some substances.

Rick Doblin — Founder of MAPS; advocate for psychedelic medicine.

Rick Strassman — Psychiatrist who conducted 1990s DMT studies; coined “spirit molecule.” DMT - The Spirit Molecule

Roland Griffiths — Johns Hopkins researcher establishing modern psilocybin research.

S

Salvia divinorum — Plant containing Salvinorin A; unique kappa-opioid dissociative. Other Compounds

Salvinorin A — Most potent natural psychedelic; non-nitrogenous diterpenoid.

San Pedro — Mescaline-containing cactus (Echinopsis pachanoi).

Santo Daime — Brazilian ayahuasca religion with legal status. Ayahuasca Ayahuasca Tourism

Schedule I — Most restrictive drug classification; “no medical use, high abuse potential.”

Selective serotonin reuptake inhibitor (SSRI) — Antidepressant class; blocks psychedelic effects.

Serotonin (5-HT) — Neurotransmitter; psychedelics are structural analogs.

Serotonin syndrome — Dangerous serotonin excess; risk with MAOI combinations.

Set and setting — Mental state and environment shaping psychedelic experience. Set, Setting and the Substance

Shulgin, Alexander “Sasha” — See Alexander Shulgin.

Shulgin rating scale — Plus/minus system for recording psychedelic effects. Tryptamines Phenethylamines

Sigma-1 receptor — Protein potentially involved in DMT effects.

Silent darknessTerence McKenna’s recommended setting for deep experiences.

Solomon Snyder — Neuroscientist who discovered opioid receptors.

Spiritual emergency — Stanislav Grof’s term for challenging transformative experience.

Stephen Szára — First to inject pure DMT in humans (1956). DMT

Synesthesia — Cross-sensory perception (seeing sounds, hearing colors).

Synthetic — Laboratory-created rather than naturally occurring.

T

Tabernanthe iboga — African shrub containing ibogaine. Ibogain

Tachyphylaxis — Acute tolerance during single session.

Terence McKenna — Ethnobotanist popularizing DMT and “heroic doses.”

Therapeutic index — Ratio of toxic to therapeutic dose; safety measure.

Therapeutic window — Dose range producing desired effects without toxicity.

Threshold dose — Minimum amount producing barely perceptible effects.

Tryptamines — “Tryptamines I Have Known And Loved”; Shulgin’s tryptamine compendium.

Timothy Leary — Harvard psychologist turned countercultural icon.

Tolerance — Reduced response requiring higher doses for same effect.

Transpersonal psychology — Field studying experiences beyond individual ego.

Trip — Colloquial term for psychedelic experience. Perspectives and Framing

Trip killer — Substance ending psychedelic effects (benzodiazepines, antipsychotics).

Trip report — Detailed account of psychedelic experience.

Trip sitter — Sober companion ensuring safety during experience.

Tryptamine — Core structure of DMT, psilocin, LSD, serotonin.

Tryptophan — Amino acid precursor to serotonin and DMT.

U

UDV (União do Vegetal) — Brazilian ayahuasca religion.

Underground therapy — Illegal psychedelic-assisted therapy.

Unity experience — Feeling of oneness with universe/others.

V

Vasoconstriction — Blood vessel narrowing; side effect of ergot derivatives.

Visual acuity enhancement — Increased visual detail perception.

Visual drifting — Objects appearing to breathe or flow.

Visionary state — Immersive visual experience transcending ordinary perception.

W

War on Drugs — Political campaign criminalizing psychedelics since 1970s.

Wasson, R. Gordon — Publicized psilocybin mushrooms to Western world.

William James — Philosopher/psychologist who experimented with nitrous oxide.

X

Xenobiotic — Foreign substance metabolized by body.

Y

Yagé — Alternative name for Ayahuasca.

Yopo — Anadenanthera snuff containing DMT and 5-MeO-DMT.

Z

Zendo Project — MAPS harm reduction services at festivals.


Additional Key Concepts

Bioassay — Testing substance effects on living organism; Shulgin’s self-experimentation method.

Consensual reality — Shared ordinary perception; contrasted with psychedelic states.

Death and rebirth — Archetypal experience of ego dissolution and reconstitution.

Ineffability — Inability to adequately describe mystical/psychedelic experiences in words.

Jungian archetypes — Universal symbols emerging in psychedelic visions.

Kundalini — Energy/consciousness described in yoga; sometimes activated by psychedelics.

Liminal space — Threshold between ordinary and non-ordinary consciousness.

Noetic quality — Sense of encountering profound truth during mystical experience.

Ontological shock — Radical questioning of reality’s nature after psychedelic experience.

Paradoxical healing — Recovery through fully experiencing difficult emotions.

Radical acceptance — Complete openness to experience; key to navigating difficult trips.

Sacred geometry — Mathematical patterns in psychedelic visions.

Transcendent other — Encounter with seemingly external intelligence.

White light experience — Encounter with brilliant luminosity in mystical states.

Xenolinguistics — Study of non-human languages; relevant to DMT entity communication.