Feeling pain during an experience may help us recall the experience. In a German study, participants looked at a neutral object in a picture. Those who had been undergoing painful thermal stimulation (heat) when they first saw the object remembered the picture better a year later. Participants were also asked to view normal household items. Sometimes they would be put through some amount of pain, and other times they were not. After viewing the pictures, the volunteers were asked to state whether they remembered seeing a certain object. The results showed that regardless of the pain applied, 75% of the objects were remembered. A type of magnetic resonance imaging (fMRI) showed that emotionally charged memories lasted longer, as did strong bodily sensations.
Source: BioRxiv.org (online), December 24, 2015, revised January 6, 2016; Science News, February 6, 2016