WARNING: Distressing content
Dave Pounds can trace his alcohol addiction to a few gruesome hours on the evening of May 12 1976, when his "idyllic, middle England" childhood was thrown into turmoil.
Back then, the 12-year-old spent most of his free time playing cricket or cycling around the fields near his family home in Leicestershire.
His mother, Margaret, who worked in a restaurant, was offered a lift home by a colleague that evening (Pounds' father, a space science professor, was working overnight in Durham). She then invited her co-worker inside for what was supposed to be a quick mug of coffee.
Unable to sleep, Pounds remembers creeping in his dressing gown to the U-shaped bend in their staircase, where he saw the pair talking in the lounge, before returning to his bedroom.
The details are hazy about what happened next. Pounds thinks the man made sexual advances towards his mother, which she rejected. Humiliated, the man then raped Margaret and stabbed her to death.
Pounds remembers hearing objects clattering on to the kitchen floor, plus some "noises I didn't understand then, but I do as an adult". Then he heard footsteps as the man scrambled upstairs and opened his bedroom door.
All he could hear for a minute or so was loud, panicked breathing.
"I pretended to be asleep," Pounds, 57, remembers now. "After what seemed like ages he left. I stayed in my room unable to move, not knowing where he was."
The killer, who Pounds prefers not to name, was arrested that night and later convicted of murder. Pounds never spoke to his father or his sister and brother - who were also at home that night, asleep in their own bedrooms - about what he overheard that night.
As an adult he has avoided discussing it with his wife or three children (who are now in their twenties).
Instead, he buried the trauma within him, only for it to emerge when he was 18 in the form of raw, painful "emotional flashbacks" that made him feel like he was back in his childhood bed, pretending to be asleep under the sinister gaze of his mother's killer.
His heart would start to race and his palms would become drenched in sweat.
About eight years ago, the trauma forced him to take a break from his career in business consultancy.
With no structure, he "hit the bottle" and began to self-medicate the way so many do: with alcohol.
"I think anxiety is too soft a word; it's terrifying. And when that terror hits, if the nearest thing is a bottle of vodka, I defy anybody not to take off the top. I know it's not great, but it does the job."
Alcoholism dominated his life. "Normally when I got drunk I would just fall asleep, but my family have seen me in some pretty sorry states."
One Saturday in 2014, in the pub with team-mates from his cricket team, he got through three bottles of vodka and woke up in hospital.
"Apparently when I got back from the pub I could barely stand. They [my family] couldn't understand me. I think that was really upsetting for the kids."
After a five-week stay at the Southgate Priory hospital in north London, Pounds tried dozens of therapies, both public and private.
But he always relapsed, until 2019, when he signed up for an experiment in Bristol in which he and 13 other alcoholics were given the psychoactive drug MDMA, known by its street name ecstasy, in conjunction with psychotherapy sessions.
Developed in 1912 by the German drug company Merck, MDMA sparked great interest among doctors in the 1960s as a potential tool for enhanced psychotherapy.
But it soon became associated with nightclubs and, after causing some deaths, was listed in 1977 as a Class A drug in the UK, meaning it officially has "no medical use".
Now the drug is attracting attention again for its benefits for mental health problems. A large body of evidence now shows MDMA-assisted therapy can help people with post-traumatic stress disorder.
The Bristol trial was the world's first study using it as a treatment for addiction, says lead researcher Dr Ben Sessa, of Imperial College London.
"As an addiction psychiatrist, I was acutely aware that most cases of addiction are actually trauma-based," he says.
By stimulating the brain's production of serotonin, dopamine and noradrenaline - chemicals associated with feeling good or happy - MDMA essentially "switches off" the brain's amygdala (known as the "fear centre"), while keeping the other parts of the brain "switched on", says Sessa.
Some patients might have spent years refusing to think about certain horrific memories, either consciously or subconsciously. The theory is that MDMA can allow them to revisit those mental images with confidence and clarity.
Sessa recruited 14 adults - including Pounds - from addiction services, all of whom drank heavily every day. A history of trauma was not a prerequisite - but all of the volunteers did experience some trauma in their childhoods.
Volunteers received eight weekly psychotherapy sessions with Sessa and his colleague, Dr Laurie Higbed - two of which involved MDMA.
Pounds had never used illegal drugs and says he was nervous that morning in February 2019 when he stepped into the clinician's room where he would stay until the next morning.
After being tested to ensure he had no alcohol in his blood, he swallowed the tablet containing MDMA.
Sessa and Higbed were in the room, if he wanted them, but he lay on the bed and put on a blindfold and a pair of headphones.
As the drug kicked in he felt "really anxious" for two minutes, as he'd been warned would happen (clubbers call this "coming up").
Then, he says, "this amazing feeling comes over you. You have a clarity of thought, and calmness. Those layers of fear have been taken away."
Pounds had talked about his mother's murder in his previous therapy sessions with Sessa and Higbed, and soon after taking the drug he had a vision of being back in his bedroom as a 12-year-old boy, with the killer standing over him.
"But the room wasn't dark, I didn't feel scared. I sat up in bed and said, 'I know what you've done downstairs and I know you could probably kill me as well. But I just want to tell you, you don't frighten me any more'."
The second time he took MDMA, three weeks later, was equally remarkable.
"I spent an hour walking up and down the room, just patting my heart and talking to myself in a very positive manner about how life is going to be now we've reset."
Two years on, his emotional flashbacks have become less severe and he no longer considers himself an alcoholic. He thinks he now drinks around 14 units per week - roughly in line with government recommendations ("and maybe a bit more if Leeds United are on telly").
"I still drink, but not dangerously. I'm a social drinker."
The other volunteers also showed promising results. It was an early-stage safety trial, designed to see how volunteers responded, rather than to test whether the MDMA actually worked.
But Sessa managed to compare the results with another group of 12 alcoholics from Bristol with similar characteristics, who used talking-based therapies.
Among that group, 75 per cent were back to their pretrial levels of drinking within nine months. Among those who took MDMA, only 21 per cent returned to that level.
"That difference is staggering, you don't see results like that in human psychopharmacology," says Sessa.
Much more research is needed, and MDMA remains an illegal substance. But for Pounds, the insight he gained through those sessions has been transformative.
"It allows me to be stronger emotionally than I've been for many, many years."
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