People with more friends have higher pain tolerance, recent research has suggested.
Katerina Johnson, a doctoral student in the University of Oxford Departments of Psychiatry and Experimental Psychology, was studying whether differences in our neurobiology may help explain why some of us have larger social networks than others.
She explained, ‘I was particularly interested in a chemical in the brain called endorphin. Endorphins are part of our pain and pleasure circuitry – they’re our body’s natural painkillers and also give us feelings of pleasure. Previous studies have suggested that endorphins promote social bonding in both humans and other animals.
‘One theory, known as the brain opioid theory of social attachment, is that social interactions trigger positive emotions when endorphin binds to opioid receptors in the brain. This gives us that feel-good factor that we get from seeing our friends.
‘To test this theory, we relied on the fact that endorphin has a powerful pain-killing effect – stronger even than morphine.’
The researchers therefore used pain tolerance as a way to assess the brain’s endorphin activity. If the theory was correct, people with larger social networks would have higher pain tolerance, and this was what their study found. Friendships may really help take the pain away!
Katerina continued, ‘These results are also interesting because recent research suggests that the endorphin system may be disrupted in psychological disorders such as depression. This may be part of the reason why depressed people often suffer from a lack of pleasure and become socially withdrawn.’
During the study, participants were asked to complete a questionnaire relating to the two innermost social network layers (approximately corresponding to those individuals contacted at least once a week and once a month respectively), as well as providing information on lifestyle and personality. They then performed a test which involved squatting against the wall with knees at a 90° angle and a straight back (the wall sit test). They were asked to hold this position and endure the discomfort for as long as possible.
Even when allowing for differences in individual fitness, the study found that people who could endure this pain test for longer, also tended to have larger social networks.
