It was 9:30 AM when Tom Hulme watched the syringe full of LSD empty into his forearm. It occurred to him, over the three minutes it took to mainline the drug, that this was not a normal acid experience. He was completely sober, lying in a dummy MRI scanner in Wales' Cardiff University hospital, bathed in fluorescent light.

"I suppose I was slightly anxious," he told VICE News. "I didn't have huge reservations but I suppose with anything like this you think, 'What if it's absolutely horrendous and I have a bad time, a really bad trip?

"You're taking this in a very sterile setting. It's not like you're experiencing it in a club."

Five minutes passed, then 10. After 15 minutes, he was sure he'd been given a placebo. Then a slight tingling began.

"It was mainly the warm feeling you get, and the visual disturbances," he said. "The walls start to breathe. Colors start to appear much brighter. I wouldn't say I was anxious, but more just a little bit like, 'This is it now, how's it going to pan out.' "

By the time the drug had taken hold, a researcher was guiding him out of the fake MRI scanner — set up to help participants acclimatise to the study — and into the real one.

"It was quite clear I'd been given LSD," he recalled. "You're just cocooned in the machine, and they put these big headphones on you. You can just hear these very mechanical rhythmic noises of the scanner. And when you're tripping it's almost like hardcore rave music. I was getting quite into it, really."

Hulme was one of 20 participants in a landmark study by Professor David Nutt and Dr. Robin Carhart-Harris into the clinical applications of LSD. The research has obtained the first ever brain scans of people tripping on acid. Nutt and his colleagues are looking at evidence that psychoactive drugs could help reverse patterns of addictive or negative thinking, and say the early results are "very promising" — but the scientists face an uphill struggle to fund their continuing research.

"These drugs offer the greatest opportunity we have in mental health," said Nutt at a briefing in London on Tuesday. "There's little else on the horizon."

Nutt was the UK's most senior drug advisor until he was sacked in 2009 following his repeated calls for ministers to adopt evidence-based drug policy. Since then he and Carhartt-Harris have battled prohibitive regulations to conduct groundbreaking studies into the effects of drugs including MDMA and psilocybin on the brain.

Their work is part of a global resurgence of medical interest in LSD, psilocybin, ketamine and other controlled drugs which, trials suggest, may have medical applications in conditions from depression to post-traumatic stress disorder.

The controversy of the research makes securing funding difficult, though. The pair have been forced to innovate, and hope to raise £25,000 ($38,000) through a crowd-funding campaign at Walacea.com, which launched today. The platform itself is only six months old, and works like a Kickstarter for scientific research.

"Scientists working in controversial fields often find it hard to raise money through traditional models, but this campaign will show that there is real public appetite for research into the effects of psychedelic drugs," Walacea founder Natalie Jonk told VICE News. "Crowdfunding science is an excellent opportunity for the public to hear directly from scientists on research they are curious about."

"This research needs to happen," said one backer, Katie Anderson, explaining her support to VICE News. "So much scientific knowledge has been suppressed because of the political, anti-drug agenda in our country."

The UK's strict drug policies stand in stark contrast to broad public support for reform, and most political parties take a dim view of the clinical benefits of controlled drugs. On Wednesday the Liberal Democrats, the junior partner in the ruling coalition, announced a raft of election manifesto commitments to reform drug policy, which included the legalization of medicinal cannabis. VICE News raised the obstructions to research with Deputy Prime Minister Nick Clegg in an exclusive interview.

"I've learnt the hard way if you want to reform things, just get on with the next steps you can take," he said.

"When you say should they be given the funding to get on with the research into LSD, I say let's first do the obvious ... which is to make, where it's clinically proven to be the case, make marijuana medicinally available to those people who have conditions where it can really help."

In the meantime Carhart-Harris and Nutt have had to rely on friends and patrons to help them conduct their research. Hulme, a psychiatric nurse at Bristol infirmary, once worked in the same office as Nutt, and played five-a-side soccer with Carhart-Harris. He has been an active participant in various drug studies since 2012.

"I emailed Robin and said I'd be quite interested in taking part," he said.

"From a therapeutic angle, I'm hoping to be a part of some groundbreaking research that's going to develop some major advances in psychiatric nursing."

The volunteers were given 75 micrograms of LSD — a "moderate" dose according to Carhart-Harris, but one that "can still produce a profound state of consciousness."

The MRI scan was the first part of the experiment, and volunteers were asked questions about the experience throughout.

"One of the things they talked about in the study is how it increases empathy as well, and oneness," Hulme recalled.

"I remember saying to [the researcher] it was almost like peeling the layers off an onion. When I shut my eyes I could almost choose how far down into the experience I wanted to go."

Afterwards volunteers were given a MEG scan, which maps the magnetic fields produced by electrical currents in the brain.

"They put lots of electrodes on my head and put me in this room," Hulme recounted. "It was absolute silence. I could swear I was just hearing wind chimes within the silence. I could swear I was hearing the silence of the wind chimes."

This time, emerging from the scanner into the clinical surroundings was "a bit of a shock really," he said. "But still quite enjoyable. Everything seemed really alien and looked a bit different."

The final part of the experiment involved a series of tasks and psychometric tests.

"There was some really bizarre psychometric testing they got me to do," he said.

"I had to say if I had a supply of tin cans and I could invent anything I wanted to, or put them to any kind of use, what uses could I find. If there was string coming down from the clouds, what could I do with that scenario.

"I can't remember, because on that occasion, well, I was quite out of it, and I was just thinking of many creative things I could do with tin cans."

The volunteers had to do the study twice; once with a placebo. Hulme said that the "clunking sound of the scanner" lost its appeal without acid.

"It was the most tedious thing I'd ever done," he added.

The trip was a short one for LSD, which researchers put down to the moderate dose and intravenous administration. Its most intense effects had faded in most participants within two hours.

"I think it probably wasn't anything like a normal LSD experience," Hulme said. "Because it wasn't that kind of experience where you sit down with your nearest and dearest and have really in-depth, pseudo intellectual conversations that seem to be earth-shattering revelations in that moment. And the next day you're like, what was I on about."