A commonly used beta-blocker drug used to treat heart disease could affect a person’s subconscious attitude towards race.

Scientists, ethicists and psychiatrists at Oxford University discovered the connection after investigating the psychological effect the heart drug had on patients’ prejudice attitudes.

The study involved two groups of 18 participants who were asked to take a ‘racial Implicit Association Test’ (IAT) a few hours after taking the propranolol beta-blocker drug or a placebo.

The test involved a combination of positive and negative language, alongside images of black and white individuals. The participants were asked to use the ‘feeling thermometer’ approach - a psychological tool used to assess explicit prejudice. They were asked how ‘warm’ or ‘cold’ they felt towards the images on a rating of 1 to 10.

Researchers discovered a third of volunteers who’d taken the beta-blocker drug had a negative IAT score, meaning they were subconsciously biased towards non-racist views.

The study also found that propranolol had no effect increasing the levels of explicit racial prejudice, as well as religious and sexual prejudice.

These results were compared to the attitudes of those who took placebo pills.

Beta-blockers are commonly used in heart patients to treat chest pains and to lower heart rates. This works by blocking the activation in the peripheral ‘autonomic’ nervous system.

Researchers believe that propranolol reduces implicit racial bias because such bias is based on automatic, subconscious fear – the exact nerves which are blocked when the beta-blocker pill are taken.

Sylvia Terbeck, lead author from the study, said in a statement: “"Our results offer new evidence about the processes in the brain that shape implicit racial bias.

"Implicit racial bias can occur even in people with a sincere belief in equality. Given the key role that such implicit attitudes appear to play in discrimination against other ethnic groups, and the widespread use of propranolol for medical purposes, our findings are also of considerable ethical interest.

“Many people with medical conditions are probably already on drugs which affect subconscious bias and more research is needed into how drugs which affect our nervous system affect our moral attitudes and practices.”

Co-author Professor Julian Savulescu from the study added: "Such research raises the tantalising possibility that our unconscious racial attitudes could be modulated using drugs, a possibility that requires careful ethical analysis.

"Biological research aiming to make people morally better has a dark history. And propranolol is not a pill to cure racism. But given that many people are already using drugs like propranolol which have 'moral' side effects, we at least need to better understand what these effects are."

The study was published in the Psychopharmacology journal.

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