How do you know if a mouse is on a psychedelic? It might just shake its head. This behavior, known as the head-twitch response, signals whether a molecule is a psychedelic-like hallucinogen. Head twitch is one tool used by pharmaceutical companies racing to develop new mental health drugs. But does a mouse experience an altered state like a human? Do animals have mystical experiences? And what can we really learn about the brain, or even human consciousness, from these unwitting rodent psychonauts?

A former Navy SEAL named Craig deployed nine times over nearly three decades in the military. When he left the service, he felt lucky to have all his limbs, toes and fingers. But he found himself struggling with language and memory and rising frustration. One day he forgot his wife’s name and couldn’t remember it for hours. His wife Gretchen started looking for help online and found information about a Stanford University research study on ibogaine and veterans. Craig volunteered. On October 8, Dr. Nolan Williams, who led that ibogaine study, died. He was 42.

In 2023, supporters of Brazil’s former president Jair Bolsonaro violently stormed the capital in an attempted coup. Among Bolsonaro’s most loyal supporters were leaders in the União do Vegetal, one of Brazil’s oldest and most popular ayahuasca churches. Brazil’s laws state that electoral propaganda is forbidden inside temples and churches but former União do Vegetal members say they experienced what some called brainwashing while in an altered state.

The Noke Koi are an Indigenous group from Acre, Brazil who consider themselves guardians of the psychoactive plant brew ayahuasca, which they call “uni.” This summer, they traveled to the U.S. to spread an urgent message: their home in the Amazon is being destroyed.

When a neurosurgeon claimed he glimpsed the afterlife during a coma, skeptics offered a more earthly interpretation – a surge of DMT produced by his own body. Was his tale of eternity a trick of the brain, or a window into something science can’t explain?

Vivaldi. Bach. The Beatles. The Johns Hopkins playlist has been the standard soundtrack in psychedelic trials at Johns Hopkins and therapy rooms around the world for more than 25 years. It also skews toward Classical and Christian music. When Sughra Ahmed, a Muslim, enrolled in a psilocybin study that used this playlist, she didn’t love what she heard. So where did this playlist come from exactly? And what can science tell us about what role music plays in a trip?

Nearly a decade ago, researchers at Johns Hopkins University gave some two dozen religious leaders from various faith backgrounds a high dose of psilocybin. Now, the long-awaited results of the study are out. Journalist Michael Pollan, who wrote about the research for The New Yorker, weighs in on whether science can ever truly measure mysticism.

Over the next ten episodes we’re going to explore two distinct camps in the world of psychedelics. On one side there’s the realm of spiritualists, mystical experiences, and psychedelic churches. And on the other are scientists, clinical trials, animal studies and psychopharmacologists. These two camps are often far apart but when they get all tangled up together things get really interesting.

A former Navy SEAL named Craig deployed nine times over nearly three decades in the military. When he left the service, he felt lucky to have all his limbs, toes and fingers. But he found himself struggling with language and memory and rising frustration. One day he forgot his wife’s name and couldn’t remember it for hours. His wife Gretchen started looking for help online and found information about a Stanford University research study on ibogaine and veterans. Craig volunteered. 

For a transcript of this episode, please visit this link.

A plan to protect the peyote cactus is taking shape on the Winnebago Reservation in Nebraska during this summer’s Native American Church of North America conference. Indigenous leaders are hustling to take their peyote proposal all the way to the White House before the November election. Producer Adreanna Rodriguez tells the story.

For a transcript of this episode, please visit this link.