Imagine a family of drugs that could treat addiction, depression and post-traumatic stress: sicknesses of the soul for which modern medicine, in all its surgical wizardry, has few cures. Substances that were a fillip to creativity and could provide those who took them with an experience comparable to seeing God or witnessing the birth of a child. Say these wonder chemicals were found: why would a society make them illegal?

The question has dogged Amanda Feilding since the 1960s, when during her teens and early 20s she first tried psychedelics. Through cannabis, LSD and magic mushrooms she found that the doors of perception were flung wide open. A blissful period of experimentation followed, in the heyday of that swinging decade, before the doors were slammed shut again in what she says was a panic about their dangers.

“It was a tragedy,” she tells me on a wet morning at Beckley Park, her home outside Oxford. “Ann Shulgin [psychedelics pioneer, and widow of its patron saint, Alexander] is a great friend. She said that on the day they heard they couldn’t use LSD or MDMA for their research they were in tears at the loss for the patients. They knew the real value of these substances to aid so many areas that are intractable.”

Feilding has dedicated her life to the reversal of this proscription, first as an artist and latterly as a tireless supporter of scientific research, courtesy of her Beckley Foundation. The dangers of abusing recreational drugs have been well documented since the 1960s, and for many scientists and policy-makers they remain as urgent as ever. Feilding hopes to show that the risks are overstated and that the laws surrounding their use should be relaxed. After decades of perseverance, there are signs that her work is coming to fruition. A handful of studies using LSD and psilocybin (the psychedelic compound found in mushrooms) has turned into a steady trickle, and the results have been promising to her cause. More remarkably, some of the theories thrown about half a century ago might be borne out by modern science.

Feilding would be the first to concede that her background is not that of a neuroscientist. She is descended from the House of Habsburg and can trace a direct line back to Charles II. Beckley Park is a Tudor hunting lodge, a mile down a muddy driveway from the main road. It has three moats and three towers, and inside is a rambling warren of antique furniture and well-stocked fireplaces. As I made my way around, dogs sheltered from the rain under rose-covered stone arches. Courtesy of her husband, Jamie, Feilding is the Countess of Wemyss and March. She is a bit like the cool aunt you never had: a little eccentric around the edges, perhaps, but warm, smart and fiercely devoted to the cause. “My background is a gain and a hindrance,” she says. “One is who one is. We lived in this incredibly beautiful house, but we never had any money or heating. I was quite isolated and I’ve always been something of an outsider.”

In 1966, when she was 22, she met Bart Huges, a Dutch chemist with whom she had a long romantic relationship. He introduced Feilding to the psychedelics and the science of consciousness, and in particular to his theories about how blood circulates in the brain. He described two theories controlling blood supply to the brain: a ‘large mechanism’ of overall blood volume, and a ‘small mechanism’ which controlled the distribution of blood in the brain more specifically. “Funnily enough, that second mechanism has been shown to be more or less what we’re picking up now in our studies,” Feilding says.

Huges’s other interest was trepanation, the practice of drilling a hole in the skull to expose the outer layers of the brain. Proponents claim that it is one of the earliest forms of surgery – ancient skulls have been found with holes in them – but it is fair to say that modern medical consensus is against it. The zenith of Feilding’s experimentation with cerebral circulation was in 1970 when she trepanned herself, an experience that was turned into an art film, Heartbeat in the Brain. A short excerpt is on YouTube. In the film the 27-year-old Feilding explains that if the public is not made aware of trepanation’s benefits then it will never be available free on the NHS. Next she chops her fringe off and drills a hole in her forehead. The available clip (the whole film is not online) cuts to the moments after the procedure. Feilding, her head bandaged and white apron stained red, wipes the blood off her face and smiles.

“The video is frustrating in terms of public perception,” she says. “But trepanation has had subtle but definite benefits for me, and to the other people I know who have had it done. Jamie had chronic headaches until he was trepanned, but not since. I think it has a lot of potential advantages. My theory is that trepanation improves the level of blood circulation round the brain to that of childhood. You get more blood into the brain with each heartbeat, and also an increase in washout of toxins. I’d suggest that cannabis and psychedelics do the same thing, but at a higher level. There are other techniques that can achieve this, like yogic breathing or cranial osteopathy, but trepanation is permanent.”

You can see why Feilding might be wary of associating these more far-out views with her campaigning. “We have always been in favour of serious, controlled use of psychedelics. For 20 years they were hailed as a wonder drug. There was a whole range of potential areas for their use. But in the 1960s the recreational aspect got out of hand. I think people like Timothy Leary did a lot of damage.” Leary, the chemist and LSD pioneer, was called America’s most dangerous man by President Richard Nixon. “There was a backlash, and the reputation of these drugs was much worse than it should have been. The harm was thoroughly exaggerated. But it left a long trail of anti-LSD feeling.”

These drugs introduce a kind of storm, but in the context of treating a pathology, it can be a useful storm

It also put the brakes on a lot of research. Between 1953 and 1973, the US government funded 116 studies of LSD, among thousands of trials in total. Test subjects included those with depression, autism and cancer as well as prisoners. As the journalist Michael Pollan put it, writing in the New Yorker recently: “The results reported were frequently positive. But many of the studies were, by modern standards, poorly designed and seldom well controlled, if at all.” The issue of controls is still an issue; unlike with, say, paracetamol, it can be hard for researchers to be blind to which of the volunteers has taken a psychedelic. (In some famous American studies, those who had been given the drug wandered around claiming to have seen God.)

In 1998, encouraged by the advent of MRI scans, Feilding founded the Beckley Foundation. “I had been exploring these ideas in art; nobody takes any notice of art, so you can say whatever you want. The new techniques meant that finally it was possible to measure, however vaguely, what actually went on in the brain. I realised that I could have more impact with science.”

The foundation works to understand drugs better, Feilding says, reducing the harm they cause and demonstrating their therapeutic potential. Often this has been a thankless role. Newspapers still feature regular horror stories about the consequences of recreational drug use, particularly among young people. These substances are controlled “more tightly than nuclear weapons”, Feilding says, even for research purposes. Scientists have been wary of being affiliated with such a murky field, and no government wants to touch it. There are few votes in encouraging people to take acid. Funding is scarce, the research expensive. Even for a small study, the MRI costs can run into the tens of thousands of pounds.

Feilding and her small team of supporters have remained undaunted and now hope that the wheel is starting to turn. In the UK, Beckley has worked closely with Professor David Nutt, the former government chief adviser who was sacked for suggesting that taking ecstasy was less dangerous than riding a horse, and Dr Robin Carhart-Harris, at Imperial College, London. Carhart-Harris and his team have just completed the first modern imaging study into the effects of LSD on the brain; full results will be out later this year. It’s the latest in a series of experiments into the effects of drugs, including psilocybin, MDMA and LSD, on the brain and consciousness, and the foundation is involved in a number of upcoming and ongoing schemes in the UK and abroad.

“These are good times. We feel like we’ve got our money on the right horse,” says Carhart-Harris. “None of it would have been possible without Amanda and the Beckley Foundation. We are about to start a clinical trail using psilocybin to treat depression, which feels historic. The World Health Organisation has estimated that depression is set to become the leading contributor to the global burden of disease. Given the magnitude of the problem, there’s huge potential that psilocybin, and maybe other psychedelics, will be a big help. Other researchers are looking at psilocybin to treat alcohol dependency or smoking addiction. And there’s also the end-stage anxiety stuff, which has been around for a little while.” A small study at UCLA suggested that psilocybin could help terminal cancer patients come to terms with their mortality. In a study led by Roland Griffiths at Johns Hopkins University, more than 70% of 36 patients given psilocybin reported that they had had one of the five most meaningful experiences of their lives.

‘We feel we’ve got our money on the right horse’: Dr Robin Carhart-Harris and his team have just completed the first modern imaging study into the effects of LSD. Photograph: Francesco Guidicini/Camera Press

Ideas about the effect of psychedelics tend to focus on something called the default-mode network, a theory that there is a group of areas that are active when the brain is at “wakeful rest” and not focused on anything else. It’s a kind of “engine running” system that operates above other functions and takes up a large amount of the brain’s energy.

“It is complicated,” says Carhart-Harris, “but one way of summarising it is that there is a principle that there are similarities among certain pathological states, like depression or addiction. Negative patterns of thought can become entrenched, with the ruts getting deeper and deeper. Think of it as being like a spiral – it’s interesting that these metaphors often turn out to speak to the underlying mechanisms, as well as being true on a poetic level. What you see with psychedelics is this dismantling of organisation, a scrambling in the cortex. These drugs introduce a kind of storm, but in the context of treating a pathology, it can be a useful storm, a reboot of the system.”

The research is bearing fruit but still needs money, which is why Feilding has come forward. The foundation depends mainly on a small number of individual donors, although they used a crowdfunding site, Walacea, to raise money for the LSD imaging study. Despite her key role, Feilding has been wary of putting herself in the foreground of publicity about the foundation. Partly this is because she is not a “scientist with a diploma”, as she puts it, but she also worries about how she comes across, that she risks being seen as a kind of aristocratic hippy with a personal interest in getting high. A Daily Mail article about her in 2010 was headlined “The Cannabis Countess”. This kind of thing is unhelpful when your goal is a revolution in international drugs policy.

As far as Carhart-Harris is concerned, Feilding needn’t worry. He argues that the research she helped to initiate has gathered so much scientific momentum that no amount of tabloid mischief can derail it. “There are as many studies now as there were in the 60s,” he says. “The increase has been exponential. It’s more exciting than it has ever been, and the results are really impressive. There has also been a generational change with drugs: more people have had experience with a range of different substances, and they’re more educated and more mature about them. They see a silly story about drugs as being silly. Even for the newspapers that thrive on sensationalism, the bigger story is that psychedelics can be used therapeutically.”

Feilding, Carhart-Harris and others inside the camp tend to be evangelical about their work. You sense this is partly because they feel like pioneers. But it is also because compared to other areas of medicine, present cures for these conditions seem so frustratingly vague. A rogue appendix can be chopped out; an infection can be treated with antibiotics. But if you are depressed, or terrified by your terminal cancer, what then? Mood-numbing drugs to manage your feelings, or a chat with a doctor in a tastefully decorated room. Psychedelics, they feel, dangle the possibility that there is a way to measure the unconscious, to go beneath the operating system and see what’s really wrong with the computer.

A lot of the research is giving drugs to normal people and then asking: ‘Have you had a nice mystical experience?’

Although results have been promising, sample sizes are still small. Even if everything goes to plan, serious clinical applications are many years and more sophisticated tests away. These drugs were not banned by accident. In 1971 the Journal of the American Medical Association warned that repeated consumption of psychedelics would usually result in permanent “personality deterioration”.

“Twenty years ago I thought that many recreational drugs were beneficial, but the more research I’ve done, the more I’ve found that the beneficial effects are pseudo phenomena, and they’re almost invariably outweighed by negative effects,” says Andrew Parrott, a professor of psychology at the University of Swansea, who has long opposed these kinds of studies. He is at the other end of the spectrum of belief on this topic, but his remarks show the scale of the task on the Beckley Foundation’s hands.

“If you look at the research, a lot of it is giving drugs to relatively normal people and then asking questions along the lines of: ‘Have you had a nice mystical experience?’ Now and again you get people who’ve had a bad reaction, but in a controlled situation on a lowish dose that’s going to be quite unusual. You get a kind of halo effect, where you ask people the right questions, and a lot of the researchers tend to be users themselves.

“Science goes in cycles, and at the moment this kind of research is very trendy. Lots of people I know are applying for research grants to look at these drugs, but theoretically I can’t really see why these drugs would benefit people with clinical disorders. Every drug has acute positive effects in the short term, but long term the negatives take over. Psilocybin and LSD will have dramatic changes to brain function, to people’s beliefs and attitudes, but if you’re looking at therapy, I don’t see it. For me, therapy always means a talking therapy.”

‘In the 1960s the recreational aspect got out of hand. There was a backlash, and the harm was thoroughly exaggerated. It left a long trail of anti-LSD feeling’: Amanda Feilding. Photograph: Richard Saker/Observer

He adds that there is a certain irony in the possible use of these drugs to treat people for tobacco addiction – one idea that is being mooted. “In the 1930s doctors prescribed smoking to treat anxiety, because smokers felt less anxious when they had a cigarette. We’ve since realised that you’re simply getting rid of withdrawal symptoms. Youngsters who take up smoking become more stressed, and then if you give up you become less stressed six months or a year later.”

When Amanda Feilding first tried psychedelics the space race was at the front of the public imagination. Cosmonauts floated in orbit; Americans walked on the moon. Dreams of galactic travel have faded over the half-century since, as the cold distances of space seem ever more insurmountable. Our brains, on the other hand, have revealed more explorable depth with every study. So if larger, more wide-ranging trials can expand on the promise of the Beckley Foundation’s work, Feilding could find herself the spiritual godmother of a large and important field of medicine.

“Amanda should enjoy her position,” says Carhart-Harris. “History will see her as one of the initiators of this whole movement, and rightly so.” And if it comes to naught, nobody can say she did not give it her all.

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