Lysergic acid diethylamide, or LSD, is a drug which produces a variety of cognitive, perceptual and behavioral changes in users. One of these is distortions in interval timing: one’s perception of (relatively) short intervals and, specifically, the ability to reliably reproduce these intervals (by, for example, switching on a light, pausing, and switching it back off).
To understand whether this temporal effect is separate from or merely a consequence of an altered state of consciousness, researchers from London and Oxford turned to a growing trend among young professionals: LSD microdosing.
Microdosing refers to the consumption of barely perceptible doses of LSD, purported to increase productivity and boost cognition without altering perception. Their results are published in Psychopharmacology.
In the study, 48 healthy adults were invited to participate in a randomized, double-blind, placebo-controlled study and given 0, 5, 10 or 20 micrograms of LSD. The authors measured subjective (perceptual) effects through self-reporting and assessed reproduction of interval timing, using periods shorter and longer than one second.
The results show that the authors were able to successfully induce temporal reproduction inaccuracies in participants without (noticeable) changes in perception, mentation or concentration. Interestingly, these effects were largely restricted to intervals of 2 to 4 seconds.
The authors present some tentative explanations, but underline their speculative nature, as more research is needed to understand the neurochemical interactions of LSD microdosing. For example, attention and working memory, which are “recruited to a greater extent for timing in this interval range”, are both implicated in the discussion. It may be that LSD increases attentional awareness, resulting in the over-reproduction of time intervals.
They additionally evoke the possibility of a dopamine-related effect, specifically via activation of the D2 dopamine receptor. Indeed, previous research has demonstrated an important relation between dopamine and time-keeping. Still, they caution against taking this hypothesis at face value, as D2 interval experiments thus far have been restricted to animals.
Mind-altering drugs present a fascinating method for understanding the brain and behavior. LSD microdosing has been praised by advocates for its ability to improve concentration, cognition, and mood, without causing hallucinations. However, more research like the present study is needed to understand the precise effects of LSD on the brain and mind, both positive and negative, and to develop guidelines for its safe use.
The study, “The effects of microdose LSD on time perception: a randomised, double-blind, placebo-controlled trial“, was authored by Steliana Yanakieva, Naya Polychroni, Neiloufar Family, Luke T. J. Williams, David P. Luke, and Devin B. Terhune.