"Some electrical wires would be attached initially to my feet.
"They would give me a shock and would continue giving me a shock every 15 or 30 seconds."
John, not his real name, underwent electrical aversion therapy at Queen's University Belfast (QUB) while a student in the 1960s. He was shown pictures of naked men and given electric shocks if he was aroused.
A spokesperson for QUB has expressed regret for the use of aversion therapy.
John had grown up in the 1950s in a rural Northern Ireland town.
"My church was a Presbyterian church, so that was quite difficult when I realised I was gay," he told BBC News NI.
"When I was about 15, I realised I am one of these people who are homosexuals and who are reviled really by the society I grew up in, so it was a big shock to me.
"I felt totally alone."
John initially spoke to his GP who, although sympathetic, arranged counselling for him at a local hospital.
However, when he went to QUB as a student in the late 1960s he was referred to the Department of Mental Health at the university.
"I was quite happy to go along with whatever they told me, I wanted to be cured," he said.
The aim of electrical aversion therapy was for him to associate homosexual desire with pain or unpleasant feelings.
"I was shown a series of what, I suppose, one would regard these days as mildly pornographic images of naked young men," John said.
"I was given gutties and these were connected up with electric wires to a voltage and I would receive the shock in my feet.
"Incidentally, I found this quite horrible because I'm quite sensitive in my feet for some reason and I managed to persuade them instead to give them to my hands.
"So they then tied something to my hands and they then tied something to each hand and I would get a shock from that."
'It was pretty horrible'
John had to press a button when he felt aroused by the pictures of men.
"When I pressed the button that meant I was aroused, then after 15 or 30 seconds if I didn't press the button again they would give me a shock," he said.
"They would continue giving me a shock until I pressed the button again to say I was no longer experiencing any arousal.
"Yes it was painful, it was pretty horrible.
"You would then associate any gay, homosexual feelings with something unpleasant - a conditioned reflex really."
John was also encouraged to date women while undergoing the therapy.
In a research paper published in the Ulster Medical Journal in 1973, academics from the departments of Mental Health, Social Studies and Psychology at QUB said their use of electrical aversion therapy was rare by that stage.
But they did still use it.
No evidence treatment worked
"We have a particular interest in the use of methods for producing heterosexual interest in exclusive homosexuals," they reported.
"In fact we rarely use electrical aversion therapy, at least as a treatment of first choice, with any of the patients referred to our clinic."
According to Dr Tommy Dickinson - the Head of the Department of Mental Health Nursing at King's College London - electrical aversion therapy never became main-stream in the UK.
"Although they were administered free of charge on the National Health Service it's only been estimated that about 1,000 people ever received the treatment," he said.
"That might seem a relatively small number, but that's not to negate the negative impact that had on those people."
Dr Dickinson is the author of Curing Queers: Mental Nurses and their Patients, 1935-1974, which examines the use of aversion therapy in the UK by reporting the experiences of those who both underwent and administered it.
"There is no evidence that the treatment worked," he told BBC News NI.
"In fact, the only evidence I came across was that it had a lasting detrimental effect on these people."
Dr Dickinson said that use of electrical aversion therapy had been almost totally abandoned by the mid-1970s in the UK.
"The most influential factor in reducing the use of these treatments was the growing gay liberation movement as queer men and women were uniting and refuting that sickness label that had been attributed to them," he said.
A spokesperson for Queen's University Belfast said that, regrettably, aversion therapy was used in a number of situations in the past.
"There is no scientific support for this approach for behaviour change," they said.
"The use of these techniques have for a long time not been supported by Queen's University or the NHS.
"While we cannot change practices of the past, Queen's University is fully committed to creating and sustaining an environment that values diversity and strongly supports its LGBT+ community."
'It wasn't working'
In the end, it was John who decided to call a halt to the treatment he was undergoing at Queen's.
"Eventually after a couple years of trying my best with this treatment I realised it simply wasn't working, my feelings for men were as they had always been and I just hadn't been aroused by girls to much extent at all," he said.
"I suppose it is barbaric, what can I say really; I would have done anything to become normal as I saw it.
"I don't think I've been damaged by it, I haven't suffered post-traumatic stress - I got over it.
"Luckily, fairly soon afterwards I did start to meet some gay people and my life changed completely then and since then things have been much better.
"I don't know how people will react to this knowledge.
"At the time it didn't seem as barbaric to me as it sounds now."