Scientists found that the stress hormone in women decreases when they speak to their female friends – supporting the ‘tend-and-befriend’ hypothesis
Former Beckman Institute postdoctoral researchers Michelle Rodrigues and Si On Yoon led the study with an interdisciplinary team. They looked at how age and familiarity with one another impacts a conversation, reviewing stress responses generated as a result.
“Women have evolved an alternative mechanism in response to stress,” said Rodrigues, an assistant professor in the Department of Social and Cultural Sciences at Marquette University.
“In order to deal with stress, women can befriend female peers.”
The team tested two theories:
According to Professor Shelley E. Taylor: “The “tend and befriend” theory builds on the observation that human beings affiliate in response to stress. Under conditions of threat, they tend to offspring to ensure their survival and affiliate with others for joint protection and comfort.”
This theory is thought by some to be a reason for women generally living longer than men, as tend-and-befriend is most commonly used by women.
2. Socio-emotional selectivity
According to Tammy English: “Socioemotional selectivity theory is a life-span theory of motivation that posits age differences in goals result from shrinking time horizons. When time is perceived as expansive, individuals will prioritize information-focused goals. When time is perceived as limited, individuals will prioritize emotion-related goals.”
In this study, the team tested the socio-emotional selectivity hypothesis, which suggests there is social “pruning” as humans advance in age and pursue more intimate, higher-quality circles of friends.
How did they test these theories?
They worked with a pool of 32 women, including 16 “older adults” aged 62-79, and 16 “younger adults” aged 18-25. Each person was either paired with a friend, a familiar conversation partner, or a stranger who was then unfamiliar.
The duos then were given a series of conversational challenges, where the person instructed her partner to arrange a set of tangrams in an order that only the former could see.
But each shape was abstract, their appearances purposefully difficult to describe.
“You could look at one and say, ‘This looks like a dog.’ Or, you could say, ‘This looks like a triangle, with a stop sign, and a bicycle wheel,'” Rodrigues said.
How did they for the stress hormone, cortisol?
Rodrigues explained that: “When you experience something stressful, if you have a stress response system that’s working as it should, the result is an elevated amount of cortisol, our primary stress hormone, which then tells our bodies to release glucose into our bloodstreams. That’s reflected in our saliva about 15 to 20 minutes after we experience it.
“If we see a rise in salivary cortisol from an individual’s baseline levels, that indicates that they are more stressed than they were at the time of the earlier measurements.”
What did they find out?
The researchers found that while the younger adult pairs communicated more efficiently with familiar partners than their older counterparts, they communicated less efficiently with unfamiliar partners.
On the other hand, the older adults demonstrated conversational dexterity, quickly articulating the abstract tangrams to friends and strangers alike. This happened even with strangers, disproving the socio-emotional theory above. The tend-and-befriend theory worked across age groups – despite the slight hesitancy.
Rodrigues further commented: “A referential communication task like this requires that you see where the other person is coming from. It seems like the younger adults are a little more hesitant in trying to do that, whereas the older adults have an easier time doing that with strangers.”