Why Do We Sleep?
Why Do We Sleep?
We are all acutely aware of the importance of sleep. The rejuvenation we feel indicates just how important sleep is to our health and wellbeing. And on average we will spend around a third of our lives doing it. But if you think about it, it is an odd thing to do.
At the end of each day, we enter a state of unconscious and become paralysed. This made our ancestors extremely vulnerable to attack from wild animals. So, the benefits must far outweigh these potential risks.
Research into sleep was a slow process. But there were a series of intriguing results that gave researchers an insight into why we sleep and what happens during it.
Why Do I Sleep?
Long story short, we still don’t know for sure. A broad take on sleep is that it gives our bodies and especially our brains time to recover.
During the day, our brain builds connections with other parts of the brain because of new experiences. During sleep, our brains take the time to determine which of these new connections are important and which are not so. The more important connections are strengthened while the lesser so are removed. Sleep is also an opportunity for the brain to be cleared of waste.
What Happens If I Don’t Get Enough Sleep?
A lack of sleep alters the way in which the genes within the body’s cells behave. The genes involved are also involved in inflammation and increase their activity. These genes react to a lack of sleep as if the body is under stress. Thinking back to our ancestors, it is speculated that their bodies would prepare themselves for injury by activating these inflammation genes which would cushion the effects of attacks by wild animals or human enemies.
Now our bodies enter this alert state, but no injury occurs.
This could easily explain the link between sleep deprivation and an increased risk of negative health outcomes such as strokes and heart disease.
Today, preparing for an injury that never happens has no beneficial effect. It could lead to some severe health complications.
Why Is It Hard To Think When I’m Tired?
The expression “half asleep” might be an accurate description of what is going on in the brain when you’re feeling slow-witted.
There is research to suggest that parts of the brain may well be asleep when it is sleep deprived. However, dolphins and whales are known to sleep with one half of their brain at a time to allow them to continue swimming and surfacing for air.
While not intentional like dolphins and whales, studies on humans have shown parts of the brain being inactive when we are sleep deprived.
How Is Modern Life Affecting Our Sleep Patterns?
Several studies show that the light bulb has led to people prolonging their day and getting less sleep. On average we go to sleep and wake up two hours later than a generation ago.
Reports suggest that around a third of working adults achieve less than six hours sleep a night, which is ten times more than it was fifty years ago. Around half of all shift workers a reported to sleep less than six hours as well.
The introduction of mobile devices has also had a massive impact on our sleep. The light they emit is disruptive to the hormones that help us go to sleep and wake up. As a result, our sleep is inhibited, and we wake up less alert in the morning.
Mobile devices are more detrimental to children and adolescents who already experience significant sleep loss. And what we are yet to establish is if there are any long-term effects of their use of these technologies.
Hopefully we’ve answered some of your questions around why we sleep. We all know it’s a non-negotiable part of our lives, but it’s also interesting to understand what is actually going on while we are asleep.