Two mandolins enter dreamily. They slowly build, occasionally fluttering, occasionally crescendoing, but always moving forward. This is what you hear in the first minute of a psychedelic treatment that could change the course of your life. The effects of the drug may not be noticeable yet, but one thing is very clear: This is a special space. The swelling soundscape surrounding you is the artistry of psychologist Bill Richards, Ph.D., who developed the playlist specifically for your psychedelic trip.

Richards works with Roland Griffiths’s lab at Johns Hopkins University, where patients get more than just conventional medicine. Instead, they get psilocybin, the active chemical in psychedelic “magic” mushrooms, so the researchers can investigate whether it can help cancer patients feel less depressed and anxious, induce mystical experiences in healthy patients, and even help smokers quit smoking. The results have been promising, adding to the continued efforts of a handful of researchers to bring psychedelics back into the scientific mainstream after decades of notoriety.

Unlike larger-scale clinical studies, psychedelic sessions are extremely personal and introspective, and as such, says Richards, it’s important for a volunteer to be supported by a compassionate staff and a safe environment. A big part of this is the playlist.

“I make the best musical choices I can, trying to separate the ‘very good’ and the ‘excellent’ on the basis of years of experience with many different people,” Richards tells Inverse.

“There’s only room for so much music in a six- to seven-hour period of time.”

Whether a session is held for treating anxiety, depression, and fear surrounding a terminal illness, or deepening meditative practice through a mystical experience — both things Richards has studied — he values music as a way to support a person’s experience.

It’s not a “trippy” playlist, though. You won’t find any psytrance or techno on the list, no Infected Mushroom, Shpongle, Daft Punk, nor any other music you might associate with altered states. Instead, there’s plenty of Brahms, Vivaldi, Mozart, and Bach. Richards says there’s a good reason for this: Orchestral music is less distracting and less likely to give room for a person to fall back on normal patterns of thinking.

“Except in the final phase, I tend to avoid music with words in the language of the volunteer, so as to discourage the rational mind from following the content of the words,” he says. “The human voice, as a solo or choir, can be very supportive, even maternal, but it is received as ‘another instrument of the orchestra.’”

While the assortment of sounds that make up his playlist is certainly important, Richards says it’s the order of songs that is crucial to a guided trip.

“In high-dose sessions, I feel that it is the structure of the music itself that matters most rather than the personal preferences of the volunteer or the guide — at least during the onset, peak and post-peak phases of the responses to the entheogen,” he says, using an alternate term for psychedelics that means “generating the divine within.”

Music during the onset of a trip, he explains, needs to be experienced as “supportive, unfolding, forward-moving.” At this stage, he suggests Edward Elgar’s “Nimrod” from his “Enigma Variations” series, which functions as a “nonverbal support system.”

“At a trip’s peak, music becomes a mirror of transcendental forms of consciousness that may not even be registered in unitive awareness, but is present if needed — like a net below a trapeze artist,” Richards says. In this playlist, the slow movement of Brahms’s Violin Concerto provides that sense of stability.

Post-peak, when powerful content is still occurring, Richards plays similarly supportive music, like the ‘transfiguration’ section of Richard Strauss’s “Death and Transfiguration.”

Compared to the potent drug at the heart of the trial, a playlist may seem secondary. But psilocybin trips can be potentially overwhelming experiences, and patients experiencing them are highly suggestible and vulnerable. As such, it’s important for psychedelic researchers to create a space in which patients can be supported through what can sometimes be a challenging time.

Richards, who has studied psychedelics for decades, sees music not as a force that actively shapes trips but as one that forms a psychological space in which a person can trip comfortably and safely.

“My preference is not to use either the word ‘augmenting’ or ‘the psychedelic experience,’” he says. “Profound states of consciousness can occur in silence, and there are many discrete states of awareness that can make up a particular ‘psychedelic experience’ (or series of ‘experiences’). With adequate dosage, I do not feel that the music ‘causes’ particular experiences; rather, it supports and undergirds the experiential flow, as content is emerging for the particular person.”

Richards is not your typical psychologist, but he’s the one you want by your side when you’re peering deep within — and as you emerge from the experience. As participants in these studies return to consensus reality, he says, the form and structure of the music become less important. The person has passed back into the world they know and are free to listen to something familiar and pleasant.

At that point, Richards says, “most any music can be explored and often enjoyed — personal favorites and music from varied cultures and genres.”

So what does he put at the very end of the playlist, when a volunteer has begun to come back to reality?

“What a Wonderful World” by Louis Armstrong.