Washington: Exposure to large amounts of
social stress can affect the body`s immune system resulting
in skin inflammation, according to a new study.
A team of researchers from the University of California
in Los Angeles (UCLA) found that individuals who exhibit
greater neural sensitivity to social rejection also exhibit
greater increases in inflammatory activity to social stress.
The researchers, who detailed their findings in the
journal Proceedings of the National Academy of Sciences, said
social stresses have a severe influence on the brain, which
responds by affecting the immune system and causing skin
Chronic inflammation can increase the risk of a variety
of disorders, including asthma, rheumatoid arthritis,
cardiovascular disease, certain types of cancer, and
depression, they said.
"It turns out, there are important differences in how
people interpret and respond to social situations," lead
author George Slavich said.
"For example, some people see giving a speech in front of
an audience as a welcome challenge; others see it as
threatening and distressing. In this study, we sought to
examine the neural bases for these differences in response and
to understand how these differences relate to biological
processes that can affect human health and well-being."
For their study, the UCLA 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 the second session, 31 of the participants received an
MRI brain scan while playing a computerised 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," Slavich said.
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."