This article was originally published by The Influence, a news site that covers the full spectrum of human relationships with drugs. Follow The Influence on Facebook or Twitter.

In the past few years, LSD, mushrooms, ketamine and MDMA are coming out of the closet, with researchers studying these substances as potential treatments for anxiety, depression, PTSD and addiction. It’s exciting research and it’s taking off for the first time since 1970, when Richard Nixon signed the Controlled Substances Act into law. The law classified hallucinogenic substances like LSD, DMT, psilocybin (the psychedelic alkaloid in mushrooms) and mescaline as Schedule I substances—the most restrictive category, reserved for drugs with “high potential for abuse and no accepted medical use.” Although there are still research bans on the drugs, scientists are getting creative about obtaining funding, while governments are facing increasing pressure to allow medical research on psychedelic substances.

Psychedelics are also popping up in art and culture. Celebrities like James Franco and Susan Sarandon are open about expanding their minds with ayahuasca. “Micro-dosing” is apparently a trend in Silicon Valley. And there’s a wave of new books about the drugs, including Tao Lin’s biography of Terence McKenna and Michael Pollan’s upcoming book on magic mushrooms.

One author at the forefront of this renewed interest is Jesse Jarnow, whose new book Heads: A Biography of Psychedelic America, came out in March. You can read an excerpt of the book here.

Heads explores psychedelic drugs’ unique and profound impact on the worlds of Silicon Valley, art, music, business and culture. Jarnow is also the author of Big Day Coming: Yo La Tengo and the Rise of Indie Rock. He has written for the Village Voice, Rolling Stone, the London Times, and recently for The Influence about a secret government drug bulletin from the 1960s.

We spoke with him to find out what exactly is going on with this “Psychedelic Spring.”

So what’s behind the re-emergence of interest in psychedelics—why now?

After the ’80s and ’90s, LSD went away for a little bit—people call it the LSD drought of the 21st century. I think it fell a little bit off the public radar in some ways. So it was sort of available for reinvention—obviously not a complete reinvention, because there’s been an ongoing counterculture—but in the public mind there was the possibility to reinvent LSD in a way closer to how it was conceived of, as a tool for therapy.

Also, some of the stigma from the drug war has worn off—certainly not all of it—but researchers can pick up these threads that were dropped when they weren’t allowed to research psychedelics any more. They’re almost literally picking up from basic research that should have been done in the ’60s but they just couldn’t. I’m laughing at all these studies coming out of Imperial College in London now, about the relationship between LSD and synesthesia, which is, you know, very well reported [among psychedelic users].

But it’s great and exciting to see to what comes next.

You and your book are part of this resurgence of interest in psychedelics that’s going on.

Right, but it wasn’t at all what I was thinking when I proposed the book. There’s this sort of psychedelic resurgence or renaissance or spring going on—I believe I first heard the term “Psychedelic Spring” from Larry Norris [of ERIE, an institute for the “non-hierarchical, community based” sharing of knowledge about the spiritual use of chemical substances]. But it was not on my mind at all, and it’s absolutely incredible what’s happened. To me, it just seemed like a good time to look back since it was the 50th anniversary of LSD hitting the market.

How did you come to the subject matter?

The original impetus for the book was that I wanted to write a cultural history of the Grateful Dead and their impact on the United States. I first started thinking about it five years ago. I wrote a proposal that got rejected—then wrote another book [Big Day Coming: Yo La Tengo and the Rise of Indie Rock]. The more I started thinking about the Grateful Dead, they seemed tied to the story of psychedelics, symbolically and literally, the way they became the ad-hoc distribution network…the Dead would play in Indiana and LSD would trickle out to Indiana.

I grew up in the early 1990s, which was really the second peak of LSD in this country after the 60s and 70s. It kind of levels out in the early 80s, then shoots up again in the mid-80s when the Grateful Dead started getting popular again. So I wanted to know what had happened between those two points. It seemed like a good time to look back and tell this story.

Where did you grow up?

I grew up on Long Island. My parents were both counter-culture heady people. My dad is an artist and filmmaker. We had the Whole Earth Catalogue [a magazine started in the late sixties that explored 60s counter-culture and the very early days of the Internet]. Growing up, I didn’t get the normal “don’t do drugs” talk.

Are psychedelics a part of your own life?

I think probably I was more of a regular user of psychedelics in college when my life wasn’t as fully formed as it is now. I don’t take psychedelics lightly—I don’t take them that often or unless it’s the right situation. I really value the time in my life when I have the space mentally to engage in something like that, but it doesn’t happen as often as I’d like it to. But I do make an effort to re-engage with it once a year minimum, if not more. I wish my life had more space for that.

I live in Brooklyn which is not really the greatest place to do that. There’s a little too much information. But psychedelics are and were extremely important to me in that earlier period, as a way of understanding creativity and thinking about creativity and the way the mind works, but also in spiritual ways as well.