Sixty years after William S Burroughs journeyed into the South American rainforests and took the hallucinogenic infusion yagé, the respected neuroscientist Andrew Lees has written a memoir telling of how the Beat legend inspired his own trip to the Amazon, where he experimented on himself with the potion to further his medical research into Parkinson’s disease.

Burroughs’s autobiographical first novel Junky concludes that “maybe I will find in yage what I was looking for in junk and weed and coke. Yage may be the final fix.” He writes of his time investigating yagé, also known as ayahuasca and the “vine of the soul”, in The Yage Letters, his collection of letters to Allen Ginsberg.

“This is not the chemical lift of C, the sexless horribly sane stasis of junk, the vegetable nightmare of peyote, or the humorous silliness of weed. This is an instant overwhelming rape of the senses,” Burroughs would write to Ginsberg on 8 July 1953. Two days later, he would write from Lima: “Yage is space-time travel. The room seems to shake and vibrate with motion … You make migrations, incredible journeys through deserts and jungles and mountains.”

Professor Andrew Lees. Photograph: PR

In Mentored By a Madman: The William Burroughs Experiment, Lees, a professor at UCL’s Institute of Neurology, writes of how in 2013 he followed Burroughs to the rainforest. In his mid-60s, he experimented with yagé himself and gained new insights that encouraged him to pursue new lines of research.

“Hallucinogenic molecules could open up frightening new vistas of exploration and if Burroughs was right, my trip to the Amazon would lead me to unimagined cures. I wanted to see whether yagé could infuse my monochromatic research canvas and open up vivid new scientific perspectives,” he writes in the memoir, which has just been published by Notting Hill Editions.

Lees takes the narcotic, which is made with a mix of the vine Banisteriopsis caapi and other plants. “Yellow and green iridescent zigzag spectra and indigo and argent helices are under my eyes, ultramarine charges come out of my arms. Jungles glide past and I see vast rivers of land accelerating past locked shorelines,” he writes.

He decided, on his return to the UK, to reinvestigate Banisteriopsis caapi as a medicine. “I had been chasing my tail, stuck in a rut and missing the way forward. I was now determined to force Nature to unveil herself in response to my questions,” he writes, going on to reveal how, with colleagues at King’s College, London, he began to examine whether yagé could reverse the signs of Parkinson’s disease in artificially afflicted marmosets, and to plan a possible clinical trial.

I suppose taking yagé for the first time in your mid-60s is a bit more interesting than when you’re 18 Andrew Lees

“Perhaps yagé would one day take its place alongside the other treatments for Parkinson’s disease, and the stunning magnificence of its phosphenes would increase inner space exploration,” he writes. “It might also aid the human spirit to comprehend its true transcendent nature and eliminate all fear. I felt sure, after my own experience, that there was something in it.”

Lees, who is the most cited researcher in Parkinson’s disease studies and in 2006 won the American Academy of Neurology’s Movement Disorders research award for his outstanding work in the field, credits Burroughs with keeping him to his medical studies in the 1960s.

He picked up a copy of Naked Lunch in 1969, feeling disillusioned with the conformity of medicine, and found, he writes, that “Burroughs had opened a crystal door that led to the moon”.

“Towards the end of my studies, I was becoming quite disenchanted with medicine, partly because of the paternalistic attitudes which were prevalent at the time. I’d almost dispensed with medicine, but I made – it sounds fantastical – but I feel I made a Mephistophelian pact with Burroughs. He wanted to be a doctor, but dropped out. The friends of his who are still alive that I’ve spoken to said he probably would have killed hundreds of people if he had ever qualified. We agreed that he’d let me complete my medical studies, provided I continued to listen to him, and not consider all his ideas just as wacky,” Lees told the Guardian.

“Burroughs started by going into the rainforest and experimenting with drugs. He wanted to be a doctor and ended up a great writer. I went into medicine, and in the twilight of my career finally got to the rainforest. I’d had the chance to take LSD in the 1960s and I’d been pretty scared to do it. I suppose taking yagé for the first time in your mid-60s is a bit more interesting than when you’re 18. It gave me courage and broke down certain rigid structures that were blocking innovations in Parkinson’s disease research.”

Facebook Twitter Pinterest Author William S. Burroughs, pictured with his typewriter in 1959. Photograph: Loomis Dean/Time & Life Pictures/Getty Image

Lees said that Burroughs “offered his brain up as a petri dish for brain research”. “His scientific explorations with mind-altering drugs made Timothy Leary look like a pussycat and also exposed him as a most unscientific individual. Burroughs was very opposed to Leary’s call to people to ‘turn on, tune in and drop out’. Burroughs had tried every single psychedelic drug before Leary came on the scene and he had a very honest, detailed approach to the experiments he was doing on himself.”

The author’s investigations, he said, “encouraged me to self-experiment with the drugs that I planned to try in patients with Parkinson’s disease”.

“This approach is now denigrated as subjective, meaningless, biased, n=1 research, despite its very noble tradition in experimental medicine and the success of maverick physicians,” said Lees, pointing to “the latest example” of its importance: “Barry Marshall’s discovery of Helicobacter pylori as a cause for peptic ulcers by drinking a potion rich in H. pylori himself”.

I suspect Burroughs would have been pleased that a medical scientist took his views seriously Andrew Lees

In his memoir, Lees writes that Burroughs “encouraged me to get away from concrete thinking, float in outer space and to run alongside a beam of light … He also reminded me that research should not be limited to institutions and that scientists must find new ways to regain the power to explore. He had added a strange grace to my research that had helped me to fly crookedly in my curiosity for cures.”

If Parkinson’s disease is to be cured, Lees said, “we do need more freedom from red tape, [and] bean-counting control … The problems we are having doing research, which are partly societal, and to do with risk aversion, have impacted on our ability to think freely and come up with unusual ideas. They are part of my reason for writing [the memoir].

The neurologist never met his mentor Burroughs, and wishes he had. “Despite his sinister appearance and spooky voice, he was a very open and courteous person in his later years. I spoke before I wrote the book with a lot of people who knew him. And I think he would have approved of the sentiments I have expressed. Although he was a total outsider, I think Burroughs did want approval from the establishment in a sense. His writing got him there and eventually he was considered to be one of the greatest American writers of the 20th century. His relationship with the medical profession was complicated and I suspect he would have been pleased that a medical scientist took his views seriously and built some into his research programme,” he said.

The forward to the book is written by James Grauerholz, executor of the Burroughs estate, who calls Lees “the consummate Watson to Burroughs’ Holmes”, adding that “my only reservation about Mentored by a Madman is that Andrew attributes so very much of his own medical insight to the effects on him of Burroughs’ ideas”.

In a review of the book just published in neurology journal Brain, the philosopher and physician Raymond Tallis writes that “it is to be hoped that Lees’s fantasia, his ‘plea for open-mindedness and freedom’ will inspire a coming generation of clinicians to think as deeply and as widely as he has”.