Psychopharmacology
November 26, 2018
Steliana Yanakieva, Naya Polychroni, Neiloufar Family et al.
169 citations
Microdoses of LSD (5, 10, and 20 μg) caused older adults to over-reproduce time intervals of 2000 milliseconds and longer, with the strongest effect at 10 μg. This temporal dilation occurred without noticeable changes in perception, mentation, or concentration, and was independent of any subjective drug effects. The findings suggest that LSD can directly alter interval timing at doses too low to produce conscious psychedelic effects, indicating a dissociation between neurochemical influences on time perception and altered states of consciousness.
Frontiers in Psychology
January 1, 2013
David P. Luke, Devin B. Terhune
81 citations
A review of published studies finds consistent evidence that serotonin agonists can temporarily produce synaesthesia, a condition where senses blend, such as seeing sounds. However, the research has many methodological flaws and little experimental work has been done. While the findings point to the serotonergic system's role in synaesthesia, the limitations prevent firm conclusions about whether chemicals truly induce genuine synaesthesia.
February 21, 2023
Simon Ruffell, Nigel Netzband, WaiFung Tsang et al.
3 citations
preprint
Ayahuasca, a psychedelic brew from the Amazon Rainforest made from the Banisteriopsis caapi vine and a DMT-containing plant like Psychotria viridis, has seen a surge in global interest since 2000. This review covers its history, pharmacology, and phenomenological effects, as well as clinical applications. Tourists increasingly travel to the Amazon to consume it, and retreat centers offering plant medicine have become a thriving business. Anecdotal reports range from evangelical accounts to stories of physical and psychological harm. The brew shows promise as a psychedelic agent warranting more empirical research into its neurochemical mechanisms and therapeutic uses.
Madeline Victore Stein, Devin B. Terhune
1 citation
preprint
Growing excitement about psychedelics in media and science often overlooks the influence of suggestion—where expectations and beliefs shape outcomes. Suggestion can distort experimental research on psychedelics' neurocognitive effects, yet it may also enhance therapeutic results when used deliberately. The authors call for greater attention to suggestion as both a source of bias and a potential tool to maximize benefits in psychedelic-assisted therapy.
medRxiv Preprint Server
May 31, 2026
Madeline V. Stein, Matt Butler, Sarah Chapman et al.
preprint
Context alone can produce psychedelic-like effects, even without an active drug. In a placebo experiment, 78 healthy participants inhaled inert medical air. When told it was nitrous oxide, they reported increased altered states of consciousness, ego dissolution, dissociation, and side effects, compared to when the gas was correctly identified as air. Time perception was not significantly affected. The strength of placebo-induced effects was predicted by individual traits of responsiveness to verbal suggestion and absorption. These results demonstrate that the context of drug administration plays a causal role in shaping psychedelic experiences.