Longevity Briefs: Wearing An Eye Mask To Bed Could Boost Your Ability To Learn

Longevity briefs provides a short summary of novel research in biology, medicine, or biotechnology that caught the attention of our researchers in Oxford, due to its potential to improve our health, wellbeing, and longevity.

The problem: When it comes to sleep, both quantity and quality count. Good quality sleep is essential for cognitive performance during the day, particularly learning and memory. Sleep is the brain’s opportunity to strengthen those synapses that were activated during the day while pruning those that have fallen out of use. Poor sleep, on the other hand, leaves us with increased levels of a neurotransmitter called adenosine. Adenosine promotes sleepiness and reduces alertness – it’s the effect of adenosine that we are trying to counteract when we consume caffeine, which blocks adenosine receptors.

One factor that can affect your sleep quality is the amount of light you are exposed to during the night. Light can interfere with your circadian rhythm, the natural cycle of your body clock that regulates your sleep and wakefulness. Most of us are exposed to some ambient light during the night, whether it be from street lighting, electronic devices or an early sunrise. Does this light have a measurable impact on our cognitive performance during the day?

The discovery: In this study, researchers found that wearing an eye mask overnight had significant benefits for memory and alertness during the day. They performed two experiments. In the first, they recruited 89 healthy adults aged 18-35 with no sleep problems. Participants were asked to wear either an eye mask that blocked out any external light, or a mask with eyeholes to serve as a control. Each participant wore one mask for a week and the other for the subsequent week, with the order being random for each participant.

For the last two days of each week, the participants went to sleep at the laboratory so that lighting conditions were the same for everyone, and performed learning and alertness tests during the day. The researchers also carried out a second experiment with 33 participants. This experiment was similar in design, except that participants also wore a device to monitor their brainwaves during the night.

The results showed that people who wore an eye mask performed better on learning tests and had shorter reaction times than those wearing the control mask. The brainwaves of the participants in the second experiment also showed that the eye mask group spent longer in slow-wave sleep, a stage of sleep associated with learning and memory. There was no significant difference in the time participants spent sleeping, suggesting that these effects were due to sleep quality, not participants being woken up earlier.

The implications: This study suggests that wearing an eye mask during sleep can enhance your memory and alertness, which are important aspects of cognitive health and longevity. This may also prevent or delay the onset of age-related cognitive decline and dementia. The benefits of an eye mask will of course depend on how much ambient light you are exposed to during sleep. The researchers chose to conduct this study during the short summer nights so that the benefits of a sleep mask would be more obvious. Previous studies have found similar benefits when participants were exposed to artificial light during the night. If you struggle to sleep with an eye mask, you may achieve the same benefits by making sure your bedroom is as dark as possible.

Most of us could be doing a lot more to improve our sleep quality. If you’re interested in finding out what those things are, check out our article on the subject, part of a three-part series on optimising sleep for health and longevity.