A deficiency of serotonin in the central nervous system may underlie some forms of depression. Existing antidepressant treatments include serotonergic drugs, and psychedelic substances also affect serotonin systems, suggesting they could play a role in depression therapy. Past attempts using both indoleamine and phenylalkylamine psychedelics have shown encouraging results, warranting further research, especially on phenylisopropylamine compounds that are only peripherally psychedelic. These entactogens or empathogens cause less distortion of normal consciousness than classic psychedelics like LSD or mescaline, making them easier to integrate into psychotherapy. Their value would be at the start of therapy to reduce fear responses, improve communication, and accelerate the therapeutic alliance.
A review of unpublished letters from the Tina and Gordon Wasson Ethnomycological Collection challenges the identification of Vedic soma as the psychoactive mushroom Amanita muscaria. In these letters, Wasson considered and rejected other psychoactive plants as candidates, including the mint Lagochilus inebrians, morning glory seeds, ergot, and the psilocybin mushroom Stropharia cubensis. The letters show that Wasson remained open to refinements of his theory.
Before becoming famous for promoting psychedelic drugs, Timothy Leary built a reputation in interpersonal psychology and developed a humanistic psychotherapy called existential-transactional psychology. This article traces his work from his 1957 book Interpersonal Diagnosis of Personality, based on research at Kaiser Foundation Hospital from 1950 to 1956, through his Harvard experiments with humanistic therapy and psychedelics from 1960 to 1963. The article emphasizes existential-transactional psychology, which Leary formulated in an unpublished treatise, The Existential Transaction. It urged psychologists to observe behavior in real-life situations without imposing medical models and to get involved in the events they studied. His Harvard psychedelic research is discussed as an application of this theory. Leary later said his expulsion from Harvard allowed him to expand his experimental design from hundreds to millions.