A new study from researchers at Johns Hopkins University suggests that psychedelics could reopen “critical periods” in the brains of mammals, offering potential for the drugs as a treatment option for those suffering from a wide range of debilitating conditions.
The findings, which were published this month in the journal Nature, “provide a new explanation for how psychedelic drugs work, say the scientists, and suggest potential to treat a wider range of conditions, such as stroke and deafness, beyond those in current studies of the drugs, such as depression, addiction and post-traumatic stress disorder. The scientists also provide a new look at molecular mechanisms impacted by psychedelics,” according to the university.
“Critical periods” refer to the time “when mammals are more sensitive to signals from their surroundings that can influence periods of brain development,” and “have been demonstrated to perform such functions as help birds learn to sing and help humans learn a new language, relearn motor skills after a stroke and establish dominance of one eye over the other eye,” the university says.
“There is a window of time when the mammalian brain is far more susceptible and open to learning from the environment,” said Gül Dölen, associate professor of neuroscience at the Johns Hopkins University School of Medicine. “This window will close at some point, and then, the brain becomes much less open to new learning.”
For the newly published study, Dölen’s team of researchers examined the effects of ibogaine, ketamine, LSD, MDMA and psilocybin on adult male mice, specifically looking “at the reopening potential of five psychedelic drugs” and building on existing research that showcased an ability of the drugs “to change normal perceptions of existence and enable a sense of discovery about one’s self or the world.”
Johns Hopkins has a breakdown of the findings:
“The research team conducted a well-established behavioral test to understand how easily adult male mice learn from their social environment. They trained mice to develop an association between an environment linked with social interaction versus another environment connected with being by themselves. By comparing time spent in each environment after giving the psychedelic drug to the mice, the researchers were able to see if the critical period opened in the adult mice, enabling them to learn the value of a social environment—a behavior normally learned as juveniles. For mice given ketamine, the critical period of social reward learning stayed open in the mice for 48 hours. With psilocybin, the open state lasted two weeks. For mice given MDMA, LSD and ibogaine, the critical period remained open for two, three and four weeks, respectively. The researchers say the length of time that the critical period stayed open in mice seems to roughly parallel the average length of time that people self-report the acute effects of each psychedelic drug.”
Dölen says that the “relationship gives us another clue that the duration of psychedelic drugs’ acute effects may be the reason why each drug may have longer or shorter effects on opening the critical period.”
“The open state of the critical period may be an opportunity for a post-treatment integration period to maintain the learning state,” Dölen adds. “Too often, after having a procedure or treatment, people go back to their chaotic, busy lives that can be overwhelming. Clinicians may want to consider the time period after a psychedelic drug dose as a time to heal and learn, much like we do for open heart surgery.”
Psychedelics have produced enormous scientific and medical discoveries in recent years, with promising new studies coming out at a near-weekly clip. Last month, a study on the effect of psilocybin on mice suggested that magic mushrooms could represent a breakthrough treatment for patients with obsessive-compulsive disorder.
