The Relationship Between Sleep and Memory

Ask yourself, how has your cognitive performance been treating you lately? Is it up to snuff, or are you a little lackluster in the ‘productivity department’ at school or work? Although there can be multiple explanations for your memory and learning capacities to go awry, one of the simplest correlations we can make involves your SLEEP.

Are you one to sacrifice some good-quality pillow time to get that last bit of paperwork done, to finish that last tv show, or to soak in one more chapter of your school textbook? Have you ever pulled an ‘all-nighter’ or something close to it in order to desperately cram for a school exam the next day? Did this affect your brain’s function the next day?

I was always bright, knowledgeable and dedicated to my schooling. And I too sacrificed a lot of sleep being a textbook rat into the late evening (and early morning) hours throughout my academic journey. I’ve stayed up all night obsessively rehearsing human anatomy and physiology details in hopes of higher scores on a quiz or a test the next day. But I don’t recall ever earning a test grade that I was very proud of on a day after very little sleep. However, I can recount stumbling on questions, having trouble recalling facts, and having difficulty with concentration. How is this decline in cognitive function tied to sleep?

Here’s a little brain buster to burst your sleep loss bubble! A complete absence of sleep creates a drop in your learning capacity and memory efficiency down to about 40% the next day. How do you think that’s going to affect your cognitive performance the next day? Reduced sleep will still create notable cognitive deficits, likely to varying degrees.

You’re much better off getting a good amount of quality shut-eye on the night before a big test or presentation, or even if you want to retain information and maximize learning the next day. You really can’t cheat sleep on either end of the equation.

Let’s break it down a little bit for clarity and understanding.

We can think of the brain as a computer, with many different functions.

The short-term ‘memory bank’ for storing new information is in an area of the brain called the hippocampus. You can think of it similar to a USB stick, which has a limited amount of storage capacity. Once it reaches capacity, it can no longer store new information. This may be up to 16 hours’ worth of storage capacity, but this capacity may be altered by factors such as sleep. Sleep before learning gets the hippocampus sharpened, and ready to learn new material, and be able to lay down new traces of memory.

When we sleep after learning new information, it’s like hitting the ‘save’ button. But this information doesn’t stay in the hippocampus as long-term memory consolidation. While we sleep, there is actually a ‘file transfer’ of the information retained in the hippocampus, that transfers learned data into another area of the brain called the cortex. This area is like the brain’s ‘hard drive’ for safe storage, and is where long-term memory consolidation occurs. Without sleep, this ‘file transfer’ and memory consolidation does not occur.

Once these ‘files’ have been shifted into the long-term ‘hard-drive’ of the cortex, you’ve essentially cleared up more space back in the short-term ‘memory bank’, the hippocampus, enabling it to once again store new information.

So we can see how important it is to acquire good sleep, both in the ability to learn and store new information, as well as be able to retain it long-term.

This connection can again be demonstrated by the relationship between sleep and Alzheimer’s disease. The single most important lifestyle factor that increases the risk for Alzheimer’s disease may be lack of sleep, which happens to be a brain disease that slowly destroys memory and thinking skills. In this case, sleep helps to clear ‘plaque’ build-up in the brain and prevents it from building up and disrupting healthy brain function.

The impact on memory and learning is only one of MANY other reasons to prioritize good sleep in your life’s wellness journey.

WHAT IS GOOD SLEEP?

Just as there are several pillars of health, there are 4 main pillars of ‘GOOD SLEEP’.

We want to ensure that we are acquiring good amounts of all stages of sleep. Deep sleep is absolutely critical for some of these important repair and restoration processes, and we cannot do well without them.

The continuity of sleep is also important, in which the duration of continuous sleep plays an important role.

The amount of sleep is probably most talked about, yet it is not much more important than the other pillars of sleep. I always say to aim for the ‘GREAT 8’ in hours. 7-9 hours is a suitable and healthy amount of sleep per night.

The timing at which we sleep is also critical. Sleep during the daylight hours will not be of the same quality as sleep during the night hours. Scheduled consistency is important.

So if you suffer from memory impairments, concentration and learning struggles, the first thing you may want to re-evaluate is your SLEEP. It is vital for both your physical and mental health.

If you need support in building a healthy bedtime routine and improving your sleep hygiene, contact me for a personalized sleep-strategy plan that will get you the ‘ZZZZZ’s’ you’ve always dreamed of!