In ‘I Heard There Was a Secret Chord,’ (Norton, Aug.), neuroscientist Daniel Levitin investigates the healing power of music.

How is music ingrained in memory, and why is that important?

A song has all these attributes, each of which is an entry point into memory. It can be the lyrics, the melody, or the sound of the person’s voice. Not to mention the way the song makes you feel—we’ve done surveys in my lab where we ask people how they choose the music they listen to. We’ve talked to 20,000 people all over Western Europe and North America, and people tell us the same thing—when I have a fight with my partner or my boss or whatever, there’s a song that will make me feel centered. In knowing what to reach for, you’re effectively self-medicating. The book is about combining that self-medication with a little understanding of what the brain is doing, how the underlying mechanisms work and how, if you were to talk to a doctor or therapist, they might guide you to more of that. It’s part of your stack of remedies.

Did any of the applications for music therapy particularly surprise you?

I think the most surprising was Joni Mitchell’s recovery [following her 2015 brain aneurysm]. I saw her right after she got back from the hospital and I didn’t think she would recover. She didn’t have the ability to walk or to speak—I remember looking in her eyes and seeing Joni there, but she wasn’t able to communicate. I got a phone call from one of the nurses who said they’d been playing music on their iPhones from the other room, and when they walked in Joni kind of tilted her head and perked up. I suggested particular music they should play and within a relatively short time, just a month or so, she began to regain something of herself. I don’t want to oversell this—maybe it was just being home for a month and in a familiar surrounding and having caregivers and better food. But the music certainly seemed to be a part of it.

What message do you hope readers take from the book?

One story readers might take away is that the brain is really the last frontier; this three and a half pound universe between our ears has untapped potential to help with healing both from injury and disease, and for general wellness and more fulfilling lives. Music can be a part of that. And I think the other story is artistic, which is that—notwithstanding the YouTube videos of elephants making paintings—we have this weirdly human propensity to create art and in particular music. When we look at archeological sites, musical instruments are often among the oldest things we find there. I think we can learn a great deal about ourselves, as a species, by looking at music and its different characteristics and how it manifests in our lives.