Aaron Alexis was looking for something. He started attending a Buddhist temple in Washington and learned to meditate; he hoped it would bring him wisdom and peace. “I want to be a Buddhist monk,” he once told a friend from the temple. His friend advised him to keep studying, and Alexis did. He learned Thai and kept going to the temple — chanting, meditating. But other things got in the way.

On 16 September 2013, Alexis drove into Washington&’s Navy Yard. It was 8 am. He’d been working there not long before, and security let him in. Minutes later, the security cameras caught him holding a shotgun — and by 9 am, 12 people were dead. Alexis killed randomly, first using his shotgun and, after running out of ammunition, the handgun belonging to a guard he’d just killed. He died after an exchange of gunfire with the police.

It took only 24 hours for a journalist to notice Alexis had been a Buddhist, prompting her to ask, “Can there be a less positive side to meditation?” Western Buddhists immediately reacted. “This man represented the Dharma teachings no more than 9/11 terrorists represented the teachings of Islam,” wrote one. Others explained that Alexis had a history of mental illness. However, some noted that meditation, for all its de-stressing and self-development potential, could take you deeper into the recesses of your mind than you may have wished for.

I’d come across the idea that, without the guidance of an expert, meditation can have adverse effects, but I’d thought this was a metaphor for the difficulties we might encounter as we venture into ourselves. Then, one day, I heard a first-hand account that opened my eyes. At the time, I was teaching a course on the psychology of spirituality and the majority of students were in their late 50s and early 60s: a combination of retired lawyers, Anglican priests and psychiatrists, and three or four yoga and meditation teachers — of whom Louise was one.

In her late 50s and lean, Louise was quiet and spoke only when she felt she had something important to say. She had taught yoga for more than 20 years, stopping only when something unexpected happened that changed her life, and she had chosen to give a presentation about this as part of her assessment on the course.

During one meditation retreat, she said – she’d been on many — her sense of self changed dramatically. “Good,” she thought initially, “it must be part of the dissolving experience.” Still, she couldn’t help feeling anxious. “Don’t worry, just keep meditating and it will go away,” her teacher told her. But it didn’t. She couldn’t get back to her usual self. It felt like something was messing with her sense of identity, how she felt in her body, the very way she looked at the world and at other people. The last day of the retreat was excruciating: her body shook, she cried and panicked.

The following day, back at home, her body was numb and she didn’t want to get out of bed.

Louise&’s husband took her to the GP; within hours, she was being seen by a psychiatrist; and she spent the next 15 years being treated for psychotic depression. Now, she talked lucidly about her illness and its possible origins (including a genetic predisposition). She explained that she had gradually taken up yoga again, but had never returned to meditation retreats. “I had to have electroconvulsive therapy,” she said.

I was stunned — and more so when I looked through medical and psychological data bases to research the possible adverse effects of meditation. One paper, written in 2001 by a British psychiatrist, told of a 25-year-old woman who, like Louise, had a serious mental health problem following meditation retreats. The first time she was admitted to hospital her symptoms included “thought disorder with flight of ideas”, elevated mood and grandiose delusions “including the belief that she had some special mission for the world… to offer ‘undying, unconditional love’ to everyone. She had no (critical) insight”.

This woman, called Miss X, was diagnosed with mania. After six weeks’ medication, her symptoms were controlled. A psychiatrist saw her regularly for two years and she started twice-weekly psychotherapy. Then she took part in a Zen Buddhist retreat and was hospitalised again. She couldn’t sleep for five days and displayed a number of unrestrained behaviours: she was irritable, sexually disinhibited and restless, made repeated praying gestures and attacked a member of the staff.

I looked further into the literature. In 1992, David Shapiro, a professor at the University of California, Los Angeles, in Irvine published an article about the effects of meditation retreats. After examining 27 people with different levels of meditation experience, he found 63 per cent of them had suffered at least one negative effect and seven per cent profoundly adverse effects.

The negative effects included anxiety, panic, depression, pain, confusion and disorientation. But perhaps only the least experienced felt them — and might several days of meditation not overwhelm those who were relatively new to the practice? The answer was no. When Shapiro divided the larger group into those with lesser and greater experience, there were no differences: all had an equal number of adverse experiences. And an earlier study had arrived at a similar, but even more surprising conclusion: those with more experience also had considerably more adverse effects than the beginners.

Amid the small pile of articles on the topic, I found two by Arnold Lazarus and Albert Ellis, co-founders of Cognitive Behavioural Therapy. In 1976, Lazarus reported that a few of his own patients had had serious disturbances after meditating and strongly criticised the idea that “meditation is for everyone”. And Ellis shared his misgivings. He believed it could be used as a therapeutic tool, but not with everyone — and overall, that it could be used only in moderation as a “thought-distracting” or “relaxing” technique. “Like tranquilisers,” he wrote, “it may have both good and bad effects — especially the harmful result of encouraging people to look away from some of their central problems, and to refrain from actually disputing and surrendering their disturbance-creating beliefs.”

I felt like an archaeologist digging up long-forgotten artefacts. How could this be completely absent in the recent research? It was conceivable that clinicians and researchers simply did not report the negative consequences of meditation, but it was more likely that the meditators themselves did not talk about it: many who encounter difficulties during or after their practice may feel they’re doing something wrong, or even that their distress is part of the process and will eventually pass. That was the case with Miss X, who eventually refused continuous treatment, explaining that her mania was just a release of blocked energy from years of not dealing with her emotions adequately. And many meditators thinking like Miss X could go towards explaining why negative reports didn’t make it into journals — because the effects were seen as mere stones on the road to peace or spiritual attainment.

However, a number of Western Buddhists are aware that not all is plain sailing with meditation; and they have even given a name to the emotional difficulties that arise — the “dark night” — borrowing the phrase coined by 16th-century Christian mystic St John of the Cross to describe an advanced stage of prayer and contemplation characterised by an emotional dryness, in which the subject feels abandoned by God. Buddhists, in principle, ought not to feel abandoned by God, but a Buddhist blog on the subject is riddled with turmoil:

“Nine years on and off of periods of deep depression, angst, anxiety and misery”; “there was a nausea that kept coming up, terrible sadness, aches and pain”; “I’ve had one pretty intense dark night, it lasted for nine months, included misery, despair, panic attacks… loneliness, auditory hallucinations, mild paranoia, treating my friends and family badly, long episodes of nostalgia and regret, and obsessive thoughts (usually about death).”

Willoughby Britton, a neuroscientist and psychiatrist at Brown University, is now trying to map what she calls “the dark side of Dharma”, an interest that arose from witnessing two people being hospitalised after intense meditation practice, together with her own experience after a retreat in which she felt an unimaginable terror. And reading through the classical Buddhist literature, she realised that such experiences were often mentioned as common stages of meditation.

“I was woefully uninformed,” she now admits. Meditation retreats easily lead people to sense the world differently: the hearing gets sharper; time moves more slowly. But the most radical change that can occur is in what Britton calls “the narrative of the self”. Try this out: focus on the present moment, nothing else than the present moment. You may be able to do it easily for a very short time. However, if you try extending this “presentness” for one or two hours, and keep trying for some days, your usual sense of self — that which has one foot in the past and the other in the future — collapses. The practice may feel great for some, but for others it is like being tossed around a roller-coaster.

Other unpleasant things can happen, too, as Britton discovered through interviews with numerous individuals: arms flap, people twitch and have convulsions; others go through euphoria or depression, or report not feeling anything at all as their physical senses go numb. Still, unpleasant though they are, if these symptoms were confined to a retreat, there wouldn’t be much to worry about — but they’re not. Sometimes they linger, affecting work, childcare and relationships. They can become a clinical health problem, which, on average, lasts for more than three years. What&’s more, meditation teachers know about it — Britton says — but researchers are usually sceptical; they ask about the psychiatric history of meditators who develop mental illness, as if meditation itself had little or nothing to do with it.

I used to think the same. But from the moment I started researching, I kept finding more and more evidence.

Take the correspondence section on the website of the revered Deepak Chopra, where readers post their questions and Chopra answers. On 11 April 2014, an individual who had been meditating for one year — and finding in it “true bliss” — describes having twice experienced a deep emotional sensation, “like something is being ripped from me”, that left her wanting to cry and yell.

Chopra&’s reply is optimistic, “It&’s both normal and okay. It just means there is some deep emotional trauma from your past that is now ready to come to the surface and be healed. After meditation I would recommend you take a few minutes and sing out loud.

“Find a song you love that resonates with the emotional tone of your pain. Listen to it at above normal volume so that you can really feel the sonic effect of the song and music. When you feel it has engaged your emotions, start to sing so that your voice translates your feelings into sound. If you do this every time you feel some unresolved residue of emotion after your meditation, it will facilitate the release and healing process.”

But what if someone like Aaron Alexis had emailed Chopra and received a reply like this? Would singing along to his favourite song, turned up nice and loud, have healed his emotional traumas and led to the wisdom he sought, rather than a killing spree? Unlikely.

Furthermore, there is a real danger that what Chopra&’s correspondent was feeling is not “normal and okay”, and that if she keeps meditating without an expert teacher, it may disturb rather than heal her.

Despite its dark side and the limitations of the current scientific research, I still think meditation is a technique with real potential for personal change, if properly guided and taught within a larger spiritual-ethical framework. But I wanted to speak to someone who, coming from the West, had embraced the Eastern meditation tradition without denying its darker side — and I found that person in Swami Ambikananda, a South African woman living in England who took religious Hindu vows and now teaches meditation and yoga in Reading.

We sat in her living room and, when I told her I was looking into the potential dark side of meditation, she asked if I had heard of Aaron Alexis.

“There is a new dogma about meditation: when it fails, its limitations are never questioned,” she said. “We are told they weren’t doing it right. But maybe neither the practice nor the person is wrong. The truth about our human condition is that no one thing works for everyone. The spiritual journey is about the unmasking of oneself, being more authentically ‘self’, and whatever path leads us there is grand for each of us. That particular path is not necessarily good for all of us — but since it has moved out of the monastic environment into the wider secular world, meditation is being sold as that which will not only make us feel better but will make us better people — more successful, stronger, convincing…”

So what about the researchers claiming that meditation per se can turn you into a better, more compassionate person?

“No, no, no,” she stressed. “Meditation needs to be embedded in its context; there are moral and emotional guidelines to be followed.”

Really? Isn’t the whole purpose of meditating to make you an enlightened and deeply moral individual; moral in the sense of being unselfish and compassionate?

“Morality can be divorced from spirituality. My ego can dissolve while I meditate. But when I get up, it&’s reconstructed. You can meditate 22 hours a day, but in those two hours you have left, you’re a human being living in matter, and this aspect of reality (she touched the ground) doesn’t care too much if you’re enlightened or not.”

After our talk, Ambikananda gave me a lift to the station. I thanked her for her time and asked again about Alexis. Did she think his killing spree had anything to do with meditation?

“I don’t know. I don’t dispute that he had serious mental health problems; but meditation probably didn’t help him either. Meditation is about looking into the abyss within. It wasn’t created to make you or me happy, but to help us fight the illusions we have and find out who we truly are.”

(The Independent)