As children learn to walk and talk, their brains are remarkably open to new information. They gather knowledge from parents, their environment, and trial and error. Teenagers do too, as they adopt the emotional and intellectual skills needed to become adults.
In adulthood, however, our minds become relatively locked, closed to new information. This saves energy and lets us navigate the world more efficiently. But that also makes it harder to adapt, learn a new language or skill, or recover from psychological or physical trauma. For those who’ve dealt with abuse, abandonment, or physical violence, that lockdown can lead to a lifetime of suffering, substance abuse, and other maladaptive behaviors.
The study, published in Nature, reflects a renaissance of using and researching psychedelics to treat a range of mental health conditions.
Scientists at Johns Hopkins University in Baltimore were investigating the drugs’ effects on “critical periods” for social learning, times when the brain is more open to new information that diminish as we age. Success in mice suggests that psychedelics can start a fresh period of learning.
If the finding bears out in future studies, the therapeutic horizon for psychedelics could expand to other opportunities to retrain the brain, including recovery from a stroke, traumatic brain injury, and even hearing loss and paralysis.
The stakes are big, and the future is promising, said lead researcher Gul Dolen, MD, PhD, an associate professor of neuroscience at Johns Hopkins University. Psychedelics “could be the key that unlocks the brain and helps people after one dose, rather than subjecting them to a lifetime of drugs.”
The psychedelic advantage
Dr. Dolen, who launched her career in addiction studies, has long been fascinated by critical periods and their influence on adult behavior.
“There have been three Nobel Prizes awarded for work on critical periods,” she said. One study in mice, for instance, identified 15 periods of social learning that define their behaviors for a lifetime.
Prior research has found that MDMA (commonly known as ecstasy) can help soldiers reconsider traumatic events on the battlefield, learn from them, and move on. That phenomenon had all the earmarks of a critical period for social learning. Perhaps, Dr. Dolen said, psychedelics could open a critical period in a soldier’s life – or a drug-addicted person’s or rape survivor’s – and give them tools to process their trauma.
In the placebo-controlled experiment, she and her team gave mice psychedelic drugs and a behavioral test to gauge the rodents’ ability to learn from their environment.
“All of the psychedelics opened the critical period of social learning for varying lengths of time,” said Dr. Dolen.
Ketamine achieved that reopening for 2 days, while the other drugs – ibogaine, LSD, MDMA, and psilocybin – opened critical periods of between 2 and 4 weeks, long after the drugs’ acute effects had worn off.
In humans, Dr. Dolen stressed, opening a critical period would be a sensitive process.
“You wouldn’t achieve these results if you dropped ecstasy and attended a rave,” she said. “The key seems to be to establish an intention for the therapy: Discuss what you hope to get from the experience, be guided through it, and process it with the therapist after the fact.”
“You need to be careful with a patient once they’re off the psychedelic,” she said, “because they’re in a state of openness and vulnerability similar to a child.”