‘She couldn’t walk, she couldn’t talk’: music therapy helped Joni Mitchell recover from a stroke – could it ward off depression and dementia too?

In 2015, Joni Mitchell suffered a catastrophic stroke. According to her friend, the musician and neuroscientist Daniel Levitin, “when she got back from the hospital, she couldn’t walk and she couldn’t talk, and the doctors were so pessimistic about her recovery, they hadn’t scheduled any follow-ups”. For a while it looked as though one of the most gifted songwriters of the 20th century would be permanently silenced.

One day, though, the nurses caring for her at her home found Levitin’s number on a piece of paper in the kitchen, and called him. They had noticed that Mitchell perked up when she heard music coming from their phones, and wondered if he had any suggestions for songs she might respond to. Remarkably, he’d helped her compile a CD of her favourite tracks for a series of albums called Artist’s Choice back in the early 2000s (it was a short-lived project from Starbucks, which had bought a record label in order to pipe music into its coffee shops). Their picks ranged from Debussy to Marvin Gaye and Leonard Cohen.

Here was the perfect solution, then: a tailor-made music therapy programme. The personalised aspect is something Levitin, whose new book is called Music As Medicine, knows to be all-important. As he explains to me from his home office in Los Angeles, “If you’re talking about therapeutic effects, you have to like the music. If you don’t like it, your walls are going to go up, your cortisol levels will spike. [You’ll say] ‘Get me away from this.’” As luck would have it, Mitchell had set down exactly what she’d need in these circumstances while she was well, and Levitin knew precisely where the nurses could find it – in the corner of the bookcase at the far end of her living room. He sent some extra material because he understood how getting in touch with a sense of herself would speed things along – Herbie Hancock’s River: The Joni Letters, and Our House, the song Graham Nash had written for and about her, with its opening lines: “I’ll light the fire / You place the flowers in the vase / That you bought today.”

Mitchell made steady progress with the help of speech and physical therapists, but Levitin sees music as a crucial part of the picture. “One of the things we know is that music you like increases dopamine, and dopamine is the neurochemical that motivates you to do things … having that music as a reminder of who she is, who she was, and what she cares about, helped her to do the very difficult job of recovery, and to follow through with the protocols of the therapists.”

In a touching anecdote from the book, Levitin describes how, a year after Mitchell’s stroke, he brought flowers on one of his regular visits. “She walked over to a cabinet by herself to get a vase for them,” he writes. “She moved some vases out of the way to find a particular one in the back, a glass vase with a single handle and flowers painted on it. ‘That’s a beautiful vase, where did you get it?’ I asked. ‘I bought it when I was living in Laurel Canyon with Graham.’ Oh. That vase.”

It’s a story that captures a key theme of the book – that music is a golden thread in the fabric of identity – and something of Levitin himself. At 67, he’s too young to be an original hippy (Mitchell is 81), but was certainly shaped by the counterculture. Born in San Francisco at the end of the 50s, he began his musical education in 1969, when he bought a stereo with money he’d earned weeding gardens and played Cream, the Rolling Stones and Chicago in his bedroom (the real epiphany came when his father insisted he get headphones. From then on the music “was suddenly coming from inside my head”). Later on, he dropped out of college to be in a local band, and when that fell apart, worked as a studio engineer and producer for the likes of Carlos Santana and Blue Öyster Cult. A fascination with the mechanics of musical perception led him to enrol part-time at Stanford University to study neuropsychology, which eventually became his day job. Now, he looks very much the professor, with reading glasses on a cord and a zippered gilet over his Oxford shirt. Only his longish, swept-back grey hair hints at an alternative sensibility.

He also happens to be a natural communicator – warm, friendly, and geekily enthused about his subject. In 2006 he published This Is Your Brain on Music, a mix of the technical and personal that became a runaway bestseller and was translated into 18 languages. It covered the gamut of musical theory – from rhythm, harmony and pitch (including the “Levitin effect” – the fact that even non musicians usually remember songs in the correct key) to their neural correlates and why our musical preferences are defined by what we hear up to the age of 18.

Music As Medicine marks a return to his core subject, after successful books on the neuroscience of ageing and the psychology of misinformation. “When I wrote This Is Your Brain on Music, I wanted to have at least a chapter on medical benefits of music, but there really wasn’t any good science about it – and I’m not one of those who doesn’t let the facts get in the way of a story. So I couldn’t write about it until now, because there’s actually been some good work,” he tells me. “We’re learning enough about the underlying mechanisms of music and brain and body that we can apply them, not just in the laboratory, but in clinics and hospitals and care facilities and outpatient treatments.”

Levitin writes about music helping treat people with Parkinson’s, Alzheimer’s, PTSD, depression, flesh wounds and back pain. But does it add up to more than just playing something nice to take your mind off things? Which of these applications offer patients the most bang for their buck? He pauses while he considers the (admittedly not very scientific) question. “Well, the best evidence we have for effectiveness comes from Parkinson’s disease, where you’ve got individuals who have difficulty walking because of impairments in the motor system. And, in part, it’s that in order to walk smoothly, you need to have some kind of an internal timer that [helps you] put one foot after the other … But if you play music at the same tempo as their natural walking pace, their gait, then they’re able to walk.” That’s welcome news for those familiar with the sputtering and freezing that characterises the disease. And, remarkably, “after having received this kind of therapy – rhythmic auditory stimulation therapy – for a few weeks, they can walk even without music, because they can hear it in their heads”.

He becomes thoughtful again: “I got stuck on the ‘bang for the buck’ question, because the biggest health concern that faces us as a society is pain: 80% of doctor visits are somebody coming in and saying, ‘Doctor, it hurts.’ In the US, pain is a $680bn drain on the economy annually, and my lab was the first to show that music produces endogenous opiates, which are analgesics.”

This raises a couple of obvious questions: sure, music is great, but can it really function as a substitute for medication? And if so, how does it work? “So I don’t think anybody’s claiming that if you listen to Abba, your headache’s going to go away. But if you’ve got chronic back pain or an injury, or you’re trying to recover from dental surgery or something, pleasurable music can get you part of the way there, so you can reduce the dose of the other stuff.” When Levitin had surgery on his hand after an accident, he was sent home with some codeine. Instead of taking the pills, he listened to music. What worked for him in that particular instance? An album called Slow Circle by Alex De Grassi (solo acoustic guitar), Sunday at the Village Vanguard by the Bill Evans Trio (classic jazz), a spot of Enya.

So, do we know what the mechanisms are? “Is there some special frequency that works best?” he asks, rhetorically. (The title of the book in the US is I’ve Heard There Was a Secret Chord, the opening lyric from Hallelujah by Leonard Cohen.) Well, the answer to that is emphatically no, he says – which slightly calls into question the wisdom of his American publishers. To illustrate the point he dismisses the idea that “a bunch of beeps and boops out of a tone generator” might work just as well, while making a very funny noise imitating one. In the lab, his team has focused on trying to determine whether the actual benefits come from distraction, from changing your overall mood, or as a result of the release of neurochemicals. Apparently, it’s all three.

He is quick to add that the effects vary from person to person, but then “it’s like antidepressants, they only work half the time for half the people. And we hunt around until we find something that works. The difference is that most of us who like music have an intuition about what music to reach for, and we can self-medicate.”

I’m struck by that last phrase and how it speaks to music’s intoxicating, transporting effects, as though it might almost be a drug itself. That, in turn, puts me in mind of music’s use in combination with drugs, whether recreationally, as in getting stoned at a gig, or more formally, as in studies of psychedelics for depression, where participants are given a blindfold and a pair of headphones and taken on a trip with Brahms.

“One of the things that cannabis does is it alters our perception of time and our attentional focus. The long association between music and cannabis comes in part from being able – for any aesthetic experience we have, whether it’s looking at a sunset, looking at a great work of visual art, attending to music, making love – to turn off the chatter of your brain and be wholly present. That’s hard for a lot of us to do, even in the face of an overwhelmingly beautiful artistic moment.”

Psychedelics, on the other hand, “are manipulating a different set of neurochemicals, and so there’s going to be a different experiential quality to it. But I think even more so than with cannabis, [with] psilocybin or LSD, you’re talking about entering the possibilities of an extended present.” In settings where the effects of the drug, rather than the music, are being studied, it’s also about facilitating free thinking and free association, and “music seems to be good at that. We don’t know exactly why. Music has a straight connection to the hippocampus, and so it can unleash memories that you might not otherwise have access to.”

That phenomenon is vividly illustrated in cases of advanced dementia, where music with strong personal associations sometimes has the ability to “wake up” patients who are otherwise pretty locked in. “There’s that wonderful scene from the Oliver Sacks documentary Alive Inside where they play [1940s bandleader] Cab Calloway for Henry Dryer, a patient at a Brooklyn nursing home,” Levitin recalls. It is indeed a wonderful scene – it’s on YouTube – with Henry able to sing chunks of Calloway from memory once the headphones have been taken off. As Sacks’s voiceover has it, “In some sense Henry is restored to himself … he’s reacquired his identity for a while through the power of music.”

Since prevention is better than cure, is there any evidence that engaging with music can protect against dementia? Yes and no. “It’s not going to prevent Alzheimer’s, but it will prevent you from seeing the effects or symptoms of Alzheimer’s for some time.” And the more active your engagement, the better. “Playing an instrument is neuroprotective, because you’re creating something. You’re orchestrating your limbs and your fingers and your vocal cords in ways that you haven’t before. No two performances are ever identical, and so they’re creating new neural pathways.” This is the concept of cognitive reserve: “I think of it as being like an athlete. If you can bench press 250 pounds on a regular basis, even with a cold and a sore arm, you’re going to be able to bench press more than I can.”

So is music a bit like a workout for the brain? “Yeah: it engages every part of the brain that we know of. It invokes memory, emotion, reward systems, eye-hand coordination, planning. There’s a lot going on there, and even if you’re not a professional musician or particularly good at it, you get all the benefits.”

That’s why Levitin recommends (prescribes?) playing music, whatever your ability or age. For anyone who can’t see the point when someone like Yo-Yo Ma has a 65-year head start, he has a clear message: the idea that you need to emulate professionals or be well trained in theory is “bullshit”. “It was 500 years ago or so, when the Europeans built the first concert halls, that we created this artificial distinction between the performers and the audience. But for tens of thousands of years, music was participatory. Still, in most cultures on the planet – not in our hyper-success-oriented western culture – people are singing unselfconsciously in groups, and nobody’s making a big deal out of it.”

There is one final thing I want to clear up: if music can shift our mood, why does it sometimes seem right to “treat” sadness with sad music? Why does going deeper into the bad feeling paradoxically make us feel better?

“I think often when we’re feeling melancholy or sad, it’s because we feel that the world has misunderstood us. And so if you put on a rousing march or something, that’s a bunch of happy people partying – more people who don’t understand you. The cognitive explanation is that if you put the right sad song on, your feelings of being cut off or sad or apart are validated. They’re understood. Neurochemically, prolactin – which is the soothing, tranquilising hormone released in mother’s milk that helps calm both the mother and the infant during nursing – that’s released when we listen to sad music, and so we feel comforted.

“When we’re depressed, we can’t really put into words the way we’re feeling, because words are just too small or too precise, and music, because of its ambiguity and its lack of precision, can capture that feeling better. It is the language of emotion. You realise: I’m no longer sitting at the edge of the cliff, staring into the abyss by myself. There’s this other person here with me, and they’ve been through this, and they’ve expressed it in this beautiful work of art.”

Joni Mitchell fans are, of course, already familiar with the concept: sometimes Blue really is the warmest colour.

• Music As Medicine by Daniel Levitin is published by Cornerstone. To support the Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.