What Does Your Pain Tolerance Say About Your Social Network?

How long an individual can endure pain may provide a clue into the size of his or her social contacts.

A new study published in Scientific Reports suggests that higher pain tolerance is associated with a bigger social network, and endorphins may have stronger painkilling effects than morphine.

Endorphins play a big role in affiliation and social connections, and when they bind with opioid receptors, individuals are left feeling with a sense of well-being, the researchers explained.

The researchers highlighted the brain opioid theory of social attachment, which is the belief that neuropeptide beta-endorphin binds to mu-opioid receptors in the central nervous system and is a key mechanism involved in social bonding.

“Social interactions trigger positive emotions when endorphin binds to opioid receptors in the brain,” said Katerina Johnson, a doctoral student at the University of Oxford in the Department of Experimental Psychology, in a press release. “This gives us that feel-good factor that we get from seeing our friends.”

The researchers hypothesized that there was a positive association between activity in the mu-opioid system and the number of social contacts that an individual has. They decided to test whether pain tolerance (a proxy for activation of the mu-opioid system) could predict social network size.

Around 100 young adults filled out a questionnaire about their connections to those who they speak with on a weekly basis and those who they’re in contact with on a monthly basis. The researchers also collected data on the participants’ personality, sociodemographics, and lifestyle.

The participants were scored on the “Big 5” personality traits: openness, conscientiousness, extraversion, agreeableness, and neuroticism.

Pain tolerance was measured using a quadriceps exercise where the participants squatted against a wall with their knees at a 90° angle and a straight back. The participants were told to stay in this position for as long as possible; the average time was around 113 seconds.

The researchers discovered that measures of pain tolerance correlated with social network size—especially with the number of individuals who the participants spoke with on a monthly basis.

Other findings from the study included:

• Agreeableness positively predicted network size but was negatively linked to pain tolerance.
• There were no significant differences in the pain test performance between men and women.
• Not surprisingly, the more fit participants performed better on the pain test, but they also tended to have smaller social networks. “So fitness was not a confounding variable in the relationship between pain tolerance and network size,” the researchers noted. The study authors added that perhaps athletic individuals had to trade social time for exercise time, or alternatively, they may exercise to get an endorphin rush instead of socializing. The researchers also suggested that it could be helpful to encourage stronger social ties among individuals with depression, in addition to other tips like exercise.
• Stress seemed to be a negative predictor of social network size. Those who reported more stress tended to have smaller networks, especially with those they contacted on a monthly basis.

The researchers called for more studies on the relationship between pain tolerance and network size.

They posited that those who have active social lives could release higher levels of endogenous opioids or have elevated receptor expression.

One of the study’s limitations was that using pain tolerance as a proxy for mu-opioid receptor signaling isn’t exactly a direct measurement. The researchers would have had to use positron emission tomography scanning and spinal taps to obtain better measurements.

However, the researchers did cite that individuals performing sustained muscular pain challenges who have higher activity in the mu-opioid system tend to report reduced pain.

“[T]here is substantial evidence that mu-opioid neurotransmission influences sensitivity not only to our physical environment, but also our social one,” the researchers concluded.