Neural and social factors contribute to ethnic differences, study finds.

Scientists have found that racial discrimination literally does hurt, showing that African Americans feel more pain and have greater activity in brain areas linked to stress and trauma than other ethnic groups.

The finding has a tragic and conflicted backstory, with stereotypic views abounding that black people have greater pain tolerance than whites, while scientific evidence routinely shows the reverse to be true.

Despite the science, studies have found that black patients, including children, typically get less pain relief in hospital than non-black patients.

The researchers, led by neuroscientist Tor Wager from Dartmouth College in the US, wanted to find out what might be upping the pain levels felt by African Americans.

There are, they explain in a paper published in Nature Human Behaviour, two main suspects.

First, innate biology could play a role, with some evidence African Americans have genetic changes that tweak the workings of the body’s inner pain killers, the endogenous opioids.

But social factors also drive pain; perceived discrimination and a heightened sense of threat have been linked to greater pain perception in African Americans.

To untangle these effects the team used MRI brain imaging to examine pain responses in 88 adult Americans of African, Hispanic and non-Hispanic White background.

Read the full story in Cosmos magazine here