How Does Sleep Make You Smarter?

Sleep is so often the thing people cut back on when trying to get ahead. We go to bed late so we can try to finish important work, or balance work with play, and if we have a few hours of free time it is likely that we will use the time doing anything but catching up on sleep!

Sleeping less even seems to be regarded as a measure of success, with people bragging that they can get by on just a few hours. While this article from Time discusses how research from the University of Utah suggests there may in fact be people who do perform well on less sleep, for many people it seems they may simply not know how poorly they are actually functioning.

Sleep really shouldn’t be bottom of the list of our priorities. It is the foundation of our overall health, and those of us who choose to instead plan our days around getting in enough rest can see great benefits. It can even make us smarter! As it turns out, sleep is actually nature’s best cognitive enhancer.



What happens to our brains when we sleep?

Sleep is important for a whole range of different reasons, and however much we try to fight it, both our brains and our bodies really do need it – and enough of it.

Our brains are made up of billions of neurons, which are connected together by synapses – and synapses are the basis of our thoughts, our memories, and important things such as physical movement, problem solving, and decision making.

When we sleep, we create new synapses to connect the neurons in our brains, and scientists have even recently observed this happening under microscope!



Learning and memory

If you imagine your day like a document on a computer that you are working on, think of sleeping as saving that document. If you simply shut down your computer without saving, you will lose the majority of your work. Sure, some of it may have been saved earlier, but the majority will be gone forever.

It’s the same concept with how our brains store memories. The two stages of sleep, “non-rapid eye movement” and “rapid eye movement” are essential to our ability to learn, in their own ways.

We need the deep sleep phase (NREM) in order to store the things we have learned throughout the day as memories, and really learn them. If we don’t sleep for long enough, our brains don’t have the time to store it all and we don’t learn as much.

The REM phase of sleep then happens in the second half of the night, and is where we record new skills we learned, whether that’s something physical or a mental process. If you don’t get enough of this type of sleep you will likely have to either partially or completely relearn things.



Attention span

When we are tired, our ability to concentrate is greatly reduced. Our attention span is much shorter than it should be, and even though we don’t realise it, we can’t actually take in as much information. This makes it much harder to form new memories, because we aren’t taking everything in to remember in the first place!

So the combination of not taking in as much information, and not giving our brains enough time to store the information as memories is not a good one. It makes us very slow to learn things, and it creates awkward situations where we are asked to recall information and trip up because we were not able to pay full attention.




As well as forming memories and learning new skills, the creation of new connections in the brain helps with solving problems, or thinking of new ways of doing things. If we don’t get enough sleep, our creative problem solving skills are reduced.

We subconsciously solve a lot of problems during the REM phase of sleep, because our brain will creatively find connections between unrelated ideas, and we often wake up feeling more clarity on any issues which may have been bugging us.

So as you can see, there are lots of ways in which we simply do not function properly if we haven’t had enough shut eye. Getting enough rest can make us more alert, able to process information more efficiently, and recall it better in the future. Combined, these factors mean that sleeping can greatly improve our cognitive abilities!