That old saying "stick and stones may break my bones, but words will never hurt me" turned out not to be true after all. Psychologists found that memories of painful emotional experiences may actually linger much longer than physical pain:
Researcher Zhansheng Chen, from Purdue University in Indiana, said that it was much harder to "re-live" physical pain than to recall social pain.
He said the evolution of a part of the brain called the cerebral cortex, which processes complex thinking, perception and language, might be responsible.
He said: "It certainly improved the ability of human beings to create and adapt, to function in and with groups, communities and cultures, and to respond to pain associated with social interactions.
"However, the cerebral cortex may also have had an unintended effect of allowing humans to relive, re-experience and suffer from social pain."
Physical pain is not remembered.
For the sake of our planet, that wouldn't be such a bad evolutionary adjustment. Make the pain more memorable... cut down on the surplus kids.