Psychedelic drugs are known to produce mind-altering effects, which can lead to profound changes in consciousness. But according to a study published in the journal Cell Reports, these compounds may alter the structure of the brain in a physical sense as well.
Researchers from the University of California, Davis (UCD), found that psychedelic compounds such as LSD, DMT and MDMA, can increase the number of connections between brain cells, or neurons.
These findings are promising because they suggest that psychedelics could be used to repair the malfunctioning brain circuits observed in people with mood disorders, such as depression, anxiety, addiction and post-traumatic stress disorder (PTSD).
"We've known for a long time that psychedelics can profoundly impact brain function," David Olson, an assistant professor in the Department of Chemistry and the Department of Biochemistry & Molecular Medicine at UCD, told Newsweek. "We now know that these functional effects are accompanied by structural changes."
The results are especially exciting, according to Olson, because these structural changes were similar to those produced by ketamine—an anesthetic that is rapidly gaining a reputation as one of the most promising ways to rapidly treat acute depression.
Recent research has shown that drugs derived from ketamine can produce a fast-acting anti-depressant effect in people who do not respond to other treatment options. These benefits could be explained by the fact that it promotes the rewiring of connections between brain cells—an ability known as 'neural plasticity.'
For their study, researchers tested the effects of various psychedelic compounds on neurons grown in a dish, as well as on those in the brains of rats and flies.
One hallmark of depression and similar disorders is that tiny structures called neurites in the prefrontal cortex—a critical brain region responsible for regulating fear response and reward—shrivel up. These neurites play an important role in brain function as they span the junctions—or synapses—between individual neurons, enabling them to communicate with each other.
In their experiments, the scientists found that psychedelics increased both the growth of neurites and the number of connections between neurons. Some compounds, such as LSD, even proved to be more potent than ketamine in promoting neurite growth. This suggests that psychedelics have the potential to reverse some of the structural changes seen in the brains of people with mood disorders.
Because the tests were conducted on animals, the results are not guaranteed to translate to humans—this can only be proven once clinical trials are conducted. However, previous research has shown that psychedelics produce similar physical effects in the brains of many species.
Intriguingly, this indicates the brain circuits that respond to psychedelics have remained unchanged throughout long periods of evolutionary history. So it is likely that the effects will be similar in humans, the researchers say.
According to Olson, discoveries such as those reported in the latest study could one day lead to a new class of drugs based on compounds that promote neural plasticity.
"Although we need more research to be sure, it is possible that psychedelics or related compounds could be used to repair the neural circuits that are damaged in these disease states," he said.
The new findings are just the latest in a growing body of research highlighting how psychedelics could be useful in treating a host of psychological problems.
A 2014 study, for example, found that LSD permanently reduced anxiety in a small number of patients. Meanwhile MDMA has been found to be useful in treating PTSD. And Ayahuasca—a potent shamanic Amazonian brew containing DMT—has shown promise in helping people cope with addiction and depression
