This entry was written by Conor Murray, PhD, formerly a post-doctoral fellow in the de Wit laboratory, and currently at UCLA. (twitter : @conormurray)
“Microdosing” is modern cultural phenomenon, involving repeated uses of very low doses of psychedelic drugs like LSD or psilocybin every few days, with a wide range of purported health benefits. Studying this phenomenon is challenging and some studies suggest that the purported health benefits might boil down to being just a “placebo effect”. Here, we ran a placebo-controlled study in the laboratory to determine whether single, low doses of LSD have health-related effects on the brain. Healthy adults visited the laboratory on three occasions, when they received placebo or one of two low doses of LSD (13 and 26 micrograms). (For comparison, the doses people use for ‘trips’ are 100-200 micrograms.). On each of these days, we measured brain responses while subjects performed a task in which they could earn rewards. Previous studies have shown that the brain responses on this task are blunted in patients with depression and other psychiatric disorders. We predicted that the low dose of LSD might produce a pattern of brain response opposite to that seen with depression.In accordance with our hypothesis, we found that the low doses of LSD enhanced brain responses to reward in the task. Surprisingly, this effect was the strongest after lower of the two doses. At this low dose, subjects were not able to detect a drug effect, and yet it changed their reward-related brain responses. One interpretation of the results is that there may be a “sweet spot” in the range of what is called a “microdose” that can improve health-related responses in the brain without disrupting people’s lives with perceptual experiences
View the paper here