Daytime naps help process unconscious information

​London: A short bout of sleep during the day may help weigh up pros and cons and gain insight before making a challenging decision, according to a study. Researchers at the University of Bristol in the UK aimed to understand whether a short period of sleep can help us process unconscious information and how this might affect behaviour and reaction time. The study, published in the Journal of Sleep Research, measured changes in people's brain activity and responses before and after a nap. Sixteen healthy participants across a range of ages were recruited to take part in an experiment. 

Participants carried out two tasks - the masked prime task and a control task where participants simply responded when they saw a red or blue square on a screen. Participants practiced the tasks and then either stayed awake or took a 90-minute nap before doing the tasks again. Using an electroencephalogram (EEG), which records the electrical activity naturally produced in the brain, researchers measured the change in brain activity and response pre-and-post nap. Sleep (but not wake) improved processing speed in the masked prime task - but not in the control task - suggesting sleep-specific improvements in processing of subconsciously presented primes. 

The findings suggest that even a short bout of sleep may help improve our responses and process information. The results suggest a potentially sleep-dependent, task-specific enhancement of brain processing that could optimise human goal-directed behaviour, researchers said. While it is already known that the process of acquiring knowledge and information recall, memory, is strengthened during sleep, this study suggests that information acquired during wakefulness may potentially be processed in some deeper, qualitative way during sleep.