Prisoners held by the regime of Chilean dictator General Augusto Pinochet were played a "torture soundtrack" of songs by Julio Iglesias and George Harrison, according to a study.
Music played at high volume during torture sessions was part of the psychological suffering endured by some of his thousands of political opponents who were detained when Pinochet seized power in 1973.
According to former prisoners, Harrison's My Sweet Lord, the soundtrack to Stanley Kubrick's film A Clockwork Orange and songs by Spanish crooner Iglesias were played for days at a time.
University of Manchester researcher Dr Katia Chornik has investigated the use of music in Pinochet's notorious torture houses, concentration camps and prisons.
One former prisoner told how her jailers would sing the Italian pop hit Gigi l'Amoroso especially for her as they were taking her to the interrogation room, and carry on whilst they were torturing her with the recording on in the background.
Another prisoner told how his tormentor's singing felt as if it normalised torture. Others said they used music to pluck up courage ahead of torture as two ex-inmates recalled listening on a pocket radio to Harry Nilsson's Without You, Alone Again by Gilbert O' Sullivan and Morning Has Broken by Cat Stevens.
Dr Chornik is also researching the revival of a choir formed in Tres Alamos, Santiago, one of the largest camps for political prisoners. The camp's authorities gambled the effort would improve its image, particularly as they were expecting an inspection of the Organisation of American States' human rights commission, she said.
She said: "Music brought prisoners together because it was a way to deal with their terrible suffering. But music was also a form of testimony. Many prisoners did not officially exist, so many were to disappear without trace and songs were a way of remembering who they were and what they believed in.
"Pinochet's system also used music to indoctrinate detainees, as a form of punishment and a soundtrack to torture. Played at intensely high volumes for days on end, the otherwise popular songs were used to inflict psychological and physical damage."
Dr Chornik is conducting a project, funded by the Leverhulme Trust, called Sounds Of Memory: Music And Political Captivity In Pinochet's Chile.