A good night's sleep can fix deep-rooted attitudes in people like race, gender biases and prejudices.
Scientists have known that sleep boosts memory formation by reviving faint neuron activity shaped during earlier periods, when an individual was awake. This process can be experimentally stimulated by giving a sleeping individual cues related to an earlier period of learning.
Xiaoqing Hu and colleagues, Department of Psychology, University of Texas at Austin have extended these findings to show that this method not only works for recently learned information but also to influence implicit attitudes learned during childhood.
The researchers focused on prejudices of race and gender. In a series of exercises designed to counter typical racial and gender biases, participants were shown pictures of men and women of different races.
They learned to associate races and genders with opposing features. A distinctive sound was associated with each type of counter-bias. The participants then took a 90-minute nap during which one sound, by random assignment, was repeatedly played to cue and reactivate a newly learned association.
Shortly after waking, the researchers found that implicit social biases were reduced preferentially for the counter-bias training reactivated during sleep. The results were the same when they were repeated again after a week.
"The study should inspire research to solve remaining issues of targeted memory reactivation during sleep so that its mechanisms are fully understood," the authors noted.
It adds further support to recent research that has shown that memories can be selectively reactivated and strengthened during slumber.