STOCKHOLM, Sweden, May 22 (UPI) -- Subjects in a test at the Karolinska Institutet in Sweden subconsciously associated pain with images they were shown during a study, despite never focusing their attention on the picture
Researchers showed 49 participants pictures, sometimes so fast they did not register the picture itself, while being given a pain cue of high or low intensity. When shown the images later while receiving an even level of a pain cue, the participants nonetheless reported feeling the high or low level cue that had been delivered when they were shown the image earlier.
"These results demonstrate that pain responses can be shaped by learning that takes place outside conscious awareness, suggesting that unconscious learning may have an extensive effect on higher cognitive processes in general," said Karin Jensen of the Department of Clinical Neuroscience at Karolinska Institutet, in a press release.
The study is published in Proceedings of the National Academy of Sciences.