Cognitive neuroscience. Unlearning implicit social biases during sleep

Area of Science:

• Psychology
• Neuroscience
• Sleep Science

Background:

• Social biases, such as implicit racial and gender bias, can operate unconsciously despite conscious endorsement of egalitarianism.
• Understanding and mitigating these biases is crucial for reducing harmful actions.

Purpose of the Study:

• To investigate the efficacy of sleep-based memory reactivation in enhancing and maintaining reductions in implicit social biases.
• To determine if specific sleep stages contribute to the consolidation of counterstereotype training.

Main Methods:

• Forty participants underwent counterstereotype training targeting implicit racial and gender bias, with each bias type linked to a specific auditory cue.
• During slow-wave sleep, one trained bias type was cued unobtrusively to facilitate memory reactivation.
• Bias levels were assessed immediately post-training, post-sleep, and one week later.

Main Results:

• Counterstereotype training significantly reduced implicit biases immediately after training.
• Bias reduction was significantly enhanced and better maintained for the sleep-cued bias compared to the non-cued bias.
• The beneficial effect of sleep-based reactivation persisted for one week and correlated with time spent in slow-wave and rapid-eye-movement sleep.

Conclusions:

• Memory reactivation during sleep effectively enhances counterstereotype training for reducing implicit social biases.
• The consolidation and long-term maintenance of bias reduction are dependent on sleep processes, particularly slow-wave and REM sleep.