Sleep training 'can reduce prejudice'

Levels of unconscious racist and sexist bias have been reduced by manipulating the way the brain learns during sleep.

According to a BBC report a team at Northwestern University, Chicago, played sounds while people slept to trigger and enforce memories of an exercise earlier in the day.

The trial on 40 people, published in the journal Science, showed the changes lasted at least a week.

Experts said the findings had potential in many situations, but also raised ethical questions.

Sexual and racial prejudice are common but may often be unintentional, says the Northwestern team.

They cite studies in computer games when people chose to shoot black characters more often than white ones or men being favoured over women despite having identical job applications.

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