Everyone knows what it feels like to not get enough sleep. But under the surface there are quite a few insidious things going on which can have a profound effect on our cognitive ability and our general quality-of-life.
Here’s our top 3 list of what happens to your brain when it doesn’t get the sleep it needs:
First, a lack of sleep can interfere with our ability to concentrate, focus our attention and remain alert. With an impaired ability to concentrate, our short-term and working-memory is impacted. This makes simple tasks seem more difficult and greatly increases our chances of making mistakes.
Not only does lack of sleep negatively affect our ability to recall information, our minds also have a way of collecting and indexing memories while we sleep. When we don’t get enough sleep, our minds don’t have the opportunity to consolidate our memories, making recall far more difficult when we’re awake.
A 2009 study conducted by American and French research teams analyzed the brain patterns of sleepers. They noted that sharp spikes in our brainwaves, known as “sharp wave ripples” coincide with the consolidation of our memories. We can think of these ripples like our brain’s “writing phase” where memories are taken from the hippocampus and written to long term memory in the brain’s neocortex. These “sharp wave ripples” only occur at very deep levels of sleep. So a bad night’s sleep is also a bad evening of “memory consolidation”.
The most insidious effects of sleep deprivation are the ones we have difficulty detecting. We tend to know when our attention is flagging. Likewise, we are usually acutely aware when we can’t remember something. But when our judgement is impaired — we may not realize it at all.
A lack of sleep causes us to make poorly thought-through decisions. What’s worse, is we may believe that we are making “good” decisions.
Ph.D sleep expert Phil Gehrman explains, “Studies show that over time, people who are getting six hours of sleep, instead of seven or eight, begin to feel that they’ve adapted to that sleep deprivation — they’ve gotten used to it. But if you look at how they actually do on tests of mental alertness and performance, they continue to go downhill. So there’s a point in sleep deprivation when we lose touch with how impaired we are.
So if you think you might be “doing okay” on less sleep, it’s entirely possible that your performance is showing something else entirely.