Not long ago, we learned something groundbreaking about sleep
It's not every day that we discover a new biological system in ourselves. That's exactly what happened in 2012 when scientists at The University of Rochester Medical Center looking carefully at brain cells confirmed we're all equipped with something called the "glymphatic system."
The glymphatic system explains how our brain is able to maintain itself. It's basically a sewage disposal system.
In 2013, we learned this system is highly active during our sleep. These findings were particularly interesting when combined with known data about neurodegenerative diseases like Alzheimer's and Parkinsons. There is still more research to be done on those fronts, but so far we see a link between the "sewage" of the brain (amyloid beta peptides) which forms into plaques on the brain when not properly expelled.
That's right. Research is suggesting good sleep can stave off alzheimers!
Good sleep day to day
"Men who sleep five hours a night have significantly smaller testicals than those who sleep seven hours or more"
To really understand the benefits of sleep, I'd need to write a book. Not a blog post, but here are some highlights:
You need good sleep before and after learning
The last part of our day we'd attribute to learning is sleep, yet our brains are indeed actively enhancing the information we've exposed to it.
As Matt Walker explains above, we see electrical activity in the brain called "sleep spindles" which enhances our learning into memory. When you think about it, the active, awake part of learning is really more about gathering the information than processing it, at least compared to the intense processing activity we see in brains during sleep.
Sleep and memory
As such, sleep deprivation affects both short and long-term memory. REM sleep is the process during our sleep where it "files" it away for easy retrievable. It follows that a loss of sleep will mean poor memory. Sleep scientists often notice patients coming in for concerns about dimensia may actually have an undiagnosed problem with sleep apnia.
And it's not just memory, studies have demonstrated individuals with more sleep are more creative and test at higher IQs. Students with more sleep on average performed better on tests than those with less.
It's a tough decision for students isn't it? What if you haven't quite studied all the material the night before the test? Are you better off staying up to pick up more information you know you haven't picked up yet...or getting sleep to ensure you can retain what you've already read? I leave it to you to ponder.
The role of the hippocampus
The role of the hippocampus in memory was proved in the 50s by researcher Brenda Milner. The patient anonymously named H.M underwent a medical procedure which required the removal of his hippocampus.
His ability to form new short- and long-term memories was damaged but he could learn physical tasks through repetition. We see clearly from H.M. that the hippocampus was crucial for long-term declarative memory. This is the kind of memory you're using when you're studying for a test. On the other hand, procedural memory is unaffected by removing the hippocampus. This kind of memory is responsible for the physical tasks H.M was able to thrive on.