1: “Scientists have discovered a revolutionary new treatment that makes you live longer. It enhances your memory and makes you more creative. It makes you look more attractive. It keeps you slim and lowers food cravings. It protects you from cancer and dementia. It wards off colds and the flu. It lowers your risk of heart attacks and stroke, not to mention diabetes. You’ll even feel happier, less depressed, and less anxious,” writes Matthew Walker.
Sound too good to be true? If it were a new drug, many of us would be skeptical and suspicious. But it’s not a new drug.
What is this amazing breakthrough? These are the proven benefits of a full night of sleep.
“While it may sound hyperbolic, nothing about this fictitious advertisement would be inaccurate,” writes Matthew in his book Why We Sleep: Unlocking the Power of Sleep and Dreams. “The evidence supporting these claims has been documented in more than 17,000 well-scrutinized scientific reports to date.”
And yet, all too often, we (including yours truly), avoid the nightly invitation to receive the full dose of this powerful therapy.
With potentially terrible consequences. Which we will explore in future posts.
2: Today, we will look at one of the many advantages which sleep provides our brains: memory, which is “especially impressive, and particularly well understood,” according to Matthew. “Sleep has proven itself time and again as a memory aid: both before learning, to prepare your brain for initially making new memories, and after learning, to cement those memories and prevent forgetting.”
While we are awake, our brains are continually acquiring and absorbing new information. For fact-based information which involves memorizing information like someone’s name, a new phone number, or where we parked your car, a region of our brain called the hippocampus helps collect our experiences and binds the details together. It provides “a short-term reservoir, or temporary information store, for accumulating new memories.”
There is a problem, however.
Our hippocampus has a limited storage capacity similar to a USB memory stick. When we exceed its limit, we “run the risk of not being able to add more information or, equally bad, overwriting one memory with another,” Matthew explains.
Our brains solve this quandary through the magic of sleep which refreshes its ability to make new memories.
3: Matthew and his colleagues proved this hypotheses by running an experiment involving daytime naps. “We recruited a group of healthy young adults and randomly divided them into a nap group and a no-nap group,” he writes. “At noon, all the participants underwent a rigorous session of learning (one hundred face-name pairs) intended to tax the hippocampus.
“As expected, both groups performed at comparable levels. Soon after, the nap group took a ninety-minute siesta in the sleep laboratory with electrodes placed on their heads to measure sleep. The no-nap group stayed awake in the laboratory and performed menial activities, such as browsing the Internet or playing board games,” notes Matthew.
At six p.m., the researchers had all of the participants perform “another round of intensive learning where they tried to cram yet another set of new facts into their short-term storage reservoirs (another one hundred face-name pairs).”
The question was straight-forward. Would the learning ability of the human brain decline with continued time throughout the day. And, if so, would sleep reverse this saturation effect thereby restoring the brain’s learning ability?
“Those who were awake throughout the day became progressively worse at learning, even though their ability to concentrate remained stable (determined by separate attention and response time tests), Matthew reports. “In contrast, those who napped did markedly better, and actually improved in their capacity to memorize facts.”
Those who took a nap had a 20 percent learning advantage.
Reflection: Am I getting enough sleep? Do I prioritize sleep?