The most famous scene in the film A Clockwork Orange is the one in which Alex DeLarge goes through a brutal conditioning process to give him an aversion to violence. But aversion conditioning is not as simple as that, and the Garcia Effect shows why.
A Clockwork Orange doesn't have heroes, but it does have a sense of morality. No one's exactly sad that Alex DeLarge gets tortured in the name of psychology, but it's still not an easy scene to watch. The violent thug gets strapped into a chair and his eyes are forced open. In front of him, a screen shows scenes of violence and sexuality as drugs that make him nauseous course through his system. He doesn't really object until they start playing Beethoven while they torture him. That particular music is the one thing he holds sacred, and he screams, knowing that not only will the nausea ruin violence and sex, but the music as well.
But this is not necessarily the case. Classical conditioning started with Pavlov, his bells, his dogs, and their food. The food is what's called the "unconditioned stimulus." It brings on salivation in the dog. The bell is the "conditioned stimulus." It's paired with the food until the two become intertwined in the mind of the dog. Eventually, the bell alone makes the dog salivate. It's not just a matter of mental association. Salivation is a physical response. The experiment showed the mind-body connection, and how it can be manipulated.
The key to this kind of conditioning was that anything could be the "conditioned stimulus." Pavlov could have exposed the dog to a certain smell, or the sight of an object, or patted them in some peculiar way when they were about to be fed. Any sort of pairing, done consistently, should produce a response. In the film, music, violence, a lady with her top off — they all produced the same results. The very idea of them makes Alex physically sick, because they were paired with the effects of the drugs.
The Garcia Effect and Sauce-Béarnaise Syndrome
As it turns out the connection isn't quite that strong, that sure, or that random. While, in the early days, many people believed that Pavlovian conditioning could bundle two random stimuli together, there were plenty who disagreed. One was John Garcia, a psychologist who in 1964 did some tests on rats. He had discovered that rats tended to be put off their usual food if they were irradiated immediately after they ate. While the experience itself probably didn't please the rats, Garcia believed that what actually turned the rats off their food was the nausea after the irradiation. More specifically, it worked because nausea is linked with food. Radiation wasn't a random stimulus. It was a stimulus that worked only because it matched the results it caused.
Over time, he did experiments that showed that rats, when exposed to radiation after drinking sweetened water, would reduce their intake of sweetened water. They didn't need to be conditioned—they were put off the sweetness after one treatment. They were put off the sweetened water even if the treatment was delayed. It was extraordinarily tough to "decondition" them. Most importantly, though, the ingestion paired with the nausea was what caused the effect. They were both "internal" stimuli. Nausea wouldn't cause an aversion to just anything, and sweetness wouldn't be avoided just because it was paired with something unpleasant.
The Garcia Effect earned a nickname, Sauce-Béarnaise Syndrome, when Martin Seligman tackled the phenomenon. He noticed that, after being violently ill at a concert just after he had had some bad sauce-béarnaise, he developed an aversion to the sauce, but not the music. That lines up with most people's experience with bad food. If they've been sick after eating something, the taste, smell, or even sight of that particular food induces nausea for quite some time afterwards. The surrounding conditions when they ate the food they are quick to forget.
Seligman designed an experiment that showed the effect a bit more clearly. He gave a group of rats a sweet treat, and while they were consuming it, rang a bell and gave them a shock. After a few rounds of this, they became afraid of the bell, as well they might, but they still loved sweets. He then gave a different group of rats the treat, and the same bell, but induced nausea in them. This group of rats couldn't care less about the bell. They did go off sugar, though.
The point is, the connection between the brain and the body is manipulable, but manipulation isn't as easy as Pavlov, or A Clockwork Orange, makes it look. This isn't to say that A Clockwork Orange isn't an artistic achievement as a film, or that the idea of using conditioning to "break" criminals wasn't a great dramatic idea based on a sound concept. We'd just like to reassure Beethoven fans that their enjoyment of the music won't be ruined by a sadistic psychologist or a bad egg salad sandwich.