Here’s a sleep hack to try if you want to wake up mentally more prepared for the day: wear an eye mask.
Blocking ambient light while you sleep can improve alertness and memory the next day, according to a study involving 122 participants across two experiments.
The study authors, from institutions in the UK, Italy and the US, say this is further evidence of the link between light and sleep – and that controlling the first can help manage the second.
“Ambient light can influence sleep pattern and timing,” the researchers write in their published paper.
“We explored how wearing an eye mask to block light during nighttime sleep affects memory and alertness, changes that could benefit everyday tasks like studying or driving.”
In the first experiment, 89 adults aged 18 to 35 were asked to wear an eye mask while they slept for a week before going without, or wearing a holey eye mask (to account for the effects of the discomfort of wearing a mask) the following week.
Lab tests performed on the last two days of each week showed that participants performed better on a word pair association task, which measures the ability to remember events and experiences, after having their eyes covered while they sleep. They also performed better on a test that measures reaction times.
For the second experiment, 33 adult volunteers between the ages of 18 and 35 were fitted with eye masks, devices to measure light intensity when they woke up, and a wearable headband to measure brain activity while they slept.
To get used to the conditions, participants slept with an eye mask intact one night and an eye mask with holes for the second night. This was followed by two nights of sleep under the same conditions, but this time with additional testing.
Again, a word pair association task revealed that wearing an eye mask helps in learning new information and forming new memories. Additionally, the data provided by the headband suggests that there is an association between wearing the mask and slower sleep time, which is known to be important when it comes to boosting memory.
“The memory benefit was predicted by the time spent in slow wave sleep while wearing the mask,” the researchers write.
“This suggests that wearing an eye mask while sleeping is an effective, cost-effective, and non-invasive behavior that could benefit cognitive function and lead to measurable impacts on daily life.”
Based on the questionnaires completed by the volunteers in both experiments, wearing the eye mask did not affect when or how long they slept, so these factors are unlikely to have influenced the test results.
Many studies have shown how important sleep is for our overall well-being and health. It can help us stay fit, it affects emotional processing in the brain, and it even influences our socialization patterns.
This study shows that an eye mask may well enhance the benefits of sleep. With so many of our daily tasks requiring alertness and higher memory performance, it might be worth considering trying it in your own nightly routine.
“Given the current climate of life hacking, sleep monitoring and cognitive enhancers, our results suggest that the eye mask is a simple, economical and non-invasive way to get the most out of a night’s sleep. sleep,” the researchers write.
The research has been published in Sleep.