The study, published in Science, began with two Pavlovian-style conditioning exercises designed to counter race and gender biases. In the first, participants were shown female faces with words linked to maths or science and in the second, black faces appeared with pleasant words.
During the tasks, two distinctive sounds were played – one that came to be strongly associated with the gender pairs and the other with the race pairs.
Following the training, participants took a 90 minute nap and once they entered a deep sleep, without their knowledge, one of the sounds was played repeatedly.
After the counter-bias training exercise, and before the nap, people’s bias tended to have fallen, but without the extra cues during sleep, their level of bias had almost recovered to baseline after the nap. However, when participants were played the sound cues during sleep, their bias scores reduced by a further 56% compared to their pre-sleep score. Their scores remained reduced by around 20% compared to their initial baseline when the participants were tested one week later.
I am filing this one under “important if true”.