Research presented at the American Psychological Association's annual meeting in San Francisco last weekend is illuminating the rapid advance of psychedelic science. New findings are adding to a growing mountain of evidence that psychedelics could be effective at treating a range of psychological problems, including post-traumatic stress disorder (PTSD), depression, and social anxiety.

The research could be laying the groundwork for legal prescribing of psychedelics including MMDA (ecstasy), ayahuasca, LSD, and psilocybin (magic mushrooms). But that's a way down the road: All of these drugs are currently illegal, classified as Schedule I under the Controlled Substances Act. (The two plants that combine to make ayahuasca are not illegal, but DMT, the mind-altering ingredient in ayahuasca, is.)

Researchers began studying psychedelics for their potential healing benefits after the discovery of LSD in 1943, but that research came to a screaming halt in the 1960s, when psychedelics were criminalized in the wake of their widespread adoption by the counterculture. Recent years, however, have seen an efflorescence of interest in the therapeutic benefits of the substances—and it's starting to pay off.

"Combined with psychotherapy, some psychedelic drugs like MDMA, psilocybin, and ayahuasca may improve symptoms of anxiety, depression and post-traumatic stress disorder," said Cristina L. Magalhaes, Ph.D., of Alliant International University Los Angeles, and co-chair of a symposium on psychedelics and psychotherapy. "More research and discussion are needed to understand the possible benefits of these drugs, and psychologists can help navigate the clinical, ethical and cultural issues related to their use."

In one study, researchers questioned 159 participants about their spirituality, their relationship with their own emotion, and their use of hallucinogens. Laurentian University's Adele Lafrance, Ph.D., reported that psychedelic use correlated with higher levels of spirituality, which were associated with fewer symptoms of anxiety and depression and improved emotional stability.

"This study reinforces the need for the psychological field to consider a larger role for spirituality in the context of mainstream treatment because spiritual growth and a connection to something greater than the self can be fostered," said Lafrance.

An ayahuasca study found similar results. That study suggested the drug could help relieve addiction and depression, as well as helping people cope with trauma.

"We found that ayahuasca also fostered an increase in generosity, spiritual connection, and altruism," said Clancy Cavnar, Ph.D., with the NÃºcleo de Estudos Interdisciplinares sobre Psicoativos (Nucleus of Interdisciplinary Psychoactive Studies).

Another study, led by Alicia Danforth, Ph.D., of the Los Angeles Biomedical Research Institute at the Harbor-UCLA Medical Center, found that a combination of psychotherapy and MDMA could treat social anxiety in adults on the autism spectrum. In that study, 12 participants with moderate to severe social anxiety twice given doses of MDMA and treated with psychotherapy, and they showed significant, long-lasting reductions in anxiety.

"Social anxiety is prevalent in autistic adults and few treatment options have been shown to be effective," said Danforth. "The positive effects of using MDMA and therapy lasted months, or even years, for most of the research volunteers."

Yet another study examined the use of psilocybin in reducing stress and anxiety in people suffering from terminal cancer. In that study, 13 subjects were given psilocybin in conjunction with psychotherapy. Researchers found that the experience helped subjects grapple with their feelings about death and develop new understandings of dying.

"Participants made spiritual or religious interpretations of their experience and the psilocybin treatment helped facilitate a reconnection to life, greater mindfulness and presence and gave them more confidence when faced with cancer recurrence," said Gabby Agin-Liebes, a doctoral candidate in psychology at Palo Alto University, who conducted the research.

After a decades-long lacuna, psychedelic science is back. How long that will take to translate into psychedelics becoming legally available by prescription remains to be seen, but the groundwork is being laid right now.