A Clockwork Orange (1971) features one of the more uncomfortable scenes in cinema, when Alex (Malcolm McDowell) is submitted to the aversion therapy tactics of the fictional Ludovico Technique. In the film, a Dr. Brodsky (Carl Duering) of the Ludovico medical facility forces Alex to watch violent images for extended periods of time as his eyes are held open with specula. He's pumped with nausea-, paralysis- and fear-inducing drugs at the same time, with the objective being the development of a nauseous association when experiencing or thinking about violence, causing an aversion. It's essentially a mechanical, Pavlovian construct that associates stimuli with negative reinforcement instead of positive.
The therapy is approved by the UK Minister of the Interior for trials on disturbed and violent individuals like Alex. The hope is to reduce prison overcrowding and cut down on street violence by effectively re-wiring people's brains against violent thoughts.
The experience renders Alex unable to perform any violent act, or engage in any sexual activity. He is also conditioned against Beethoven's 9th Symphony, used as the backdrop of the violent imagery, and formerly his favorite piece of music.