Washington: Social stress can `get under our skin`, literally, for new study has found that how our brain responds to social stressors can influence the body`s immune system resulting in skin inflammation.
Lead author George Slavich and Shelley Taylor, of the UCLA, have shown that individuals who exhibit greater neural sensitivity to social rejection also exhibit greater increases in inflammatory activity to social stress.
Although such increases can be adaptive, chronic inflammation can increase the risk of a variety of disorders, including asthma, rheumatoid arthritis, cardiovascular disease, certain types of cancer, and depression.
"It turns out, there are important differences in how people interpret and respond to social situations," said Slavich.
"For example, some people see giving a speech in front of an audience as a welcome challenge; others see it as threatening and distressing," he added.
The researchers recruited 124 individuals - 54 men and 70 women - and put them into two awkward social situations.
First, in the lab, the volunteers completed the Trier Social Stress Test (TSST), which involves preparing and delivering an impromptu speech and performing difficult mental arithmetic, both in front of a socially rejecting panel of raters wearing white lab coats.
Mouth swabs were taken before and after the public-speaking tasks to test for changes in two key biomarkers of inflammatory activity - a receptor for tumor necrosis factor-a (sTNFaRII) and interleukin-6 (IL-6).
In a second session, 31 of the participants received an MRI brain scan while playing a computerized game of catch with what they believed were two other real people.
Their results showed that individuals who exhibited greater neural activity in the dorsal anterior cingulate cortex and anterior insula during social rejection in the brain scanner also exhibited greater increases in inflammatory activity when exposed to acute social stress in the lab.
"This is further evidence of how closely our mind and body are connected. We have known for a long time that social stress can `get under the skin` to increase risk for disease, but it``s been unclear exactly how these effects occur," said Slavich.
Although increases in inflammatory activity are part of our immune system`s natural response to potentially harmful situations, Slavich noted: "frequent or chronic activation of the system may increase risk for a variety of disorders, including asthma, rheumatoid arthritis, cardiovascular disease, and even depression."
The study was published in the journal Proceedings of the National Academy of Sciences.