One small dose of a psychedelic compound could help brains better adapt to changing circumstances, potentially improving treatments for those struggling with depression, PTSD, and neurodegenerative diseases, according to experiments conducted in mice. The results of the study were reported in the journal Psychedelics. "What makes this discovery particularly significant is the sustained duration of cognitive benefits following just one psychedelic dose," Omar J. Ahmed, a psychology researcher at the University of Michigan and a co-author of the study, said in a press release. "We observed enhanced learning adaptability that persisted for weeks, suggesting these compounds may induce lasting and behaviorally meaningful neuroplasticity changes in the prefrontal cortex."Measuring Cognitive FlexibilityFigure 1. Experimental timeline and overview. (A) Experimental timeline. (B) Schematic of the SEQFR2-forward protocol. Mice have to sequentially poke left and then right within 30 s to earn a reward pellet. (C) Schematic of the SEQFR2-reversal protocol. Mice now are required to poke right and then left within 30 s to get a reward pellet. (Image Credit: Omar J Ahmed)In the experiments, researchers treated mice with a single dose of a potent hallucinogen called 25CN-NBOH. That chemical binds very specifically to a serotonin receptor, then activates it. Serotonin receptors are often associated with depression.Mice treated with the compound performed better than the mice that were not. The improvements lasted two to three weeks following administration. The results were similar in both male and female mice.The researchers essentially tested how well they could adapt to changes in rules required to perform a particular task. Such tests are considered standard ways to measure what scientists call “cognitive flexibility” — the ability to try new approaches to accomplish the same job. The mice treated with the psychedelic showed a better ability to adapt than ones who received a saline solution instead. The psychedelic mice also performed their tasks both more efficiently and more accurately.Microdosing Psychedelics as TreatmentBoth interest in and research of psychedelics as treatment have increased in recent years. Microdosing — providing tiny amounts of psychedelic drugs like psilocybin or LSD to treat some mental health conditions have shown small, but promising results. However, larger trials involving a variety of doses to more people over more time will likely be necessary before such treatments become commonly prescribed to humans by psychiatrists. Some researchers are also calling for more rigorous standards to evaluate such drugs. More to Research for PsychedelicsAuthors of the new mouse study agree there needs to be more research — especially in exactly how these compounds essentially rewire the brain. But they are encouraged that a single dose seems to have relatively long-lasting effects in mice.“A key question is what happens with two, three, or even twenty doses taken over several months,” Ahmed said. “Is every additional dose increasingly beneficial for flexible learning or is there a plateau effect or even a negative effect of too many doses? These are important questions to answer next in the quest to make psychedelic medicine more rational and mechanistic.”Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Before joining Discover Magazine, Paul Smaglik spent over 20 years as a science journalist, specializing in U.S. life science policy and global scientific career issues. He began his career in newspapers, but switched to scientific magazines. His work has appeared in publications including Science News, Science, Nature, and Scientific American.