It might seem that we know everything there is to know about the human body. We can perform brain surgeries, organ transplants, and so many more incredible procedures, but we are still far from knowing every little thing about our biology. In fact, the reasoning behind one of our most basic functions, sleep, is still largely a mystery.
When you think about it, sleep would have been very dangerous in an evolutionary context. We are completely unconscious and helpless, vulnerable to many predators. And the state of tiredness and sleepiness which comes when we don’t get enough rest makes us far less focused and more likely to make major mistakes. Therefore, sleep must have some incredible benefits to make up for these drawbacks.
And we aren’t the only ones who sleep. Almost every known animal sleeps as well, with schedules as varied from resting a few hours a day to hibernating for months. The prevailing theory for most of the animal kingdom is that sleep conserves energy, and sleep schedules keep animals active only when it is necessary, such as when food sources are available.
Sleep may also simply be unavoidable. Live Science explains that even small neuronal networks found in labs go from stages of activity to inactivity throughout the day. Even neurons need their sleep, and the larger that neuron networks get, the more complex this rest becomes. It would be a mess for half of the neurons in your brain to just stop working at once, and so sleep coordinates this period of rest, allowing the brain to function cohesively for the rest of the day.
Resting might also give the brain an opportunity to clean things up. As our brains function, they build up waste products, and sleep gives the brain an opportunity to flush out these fluids. Without it, too much of these products might accumulate, eventually causing the brain to shut down.
Yet another benefit is improving brain plasticity. When we make new memories, our brains store them by forming connections between neurons. And research has shown that as you sleep, the connections for memories you’ve made that day are greatly strengthened. This is the reason why not getting enough sleep can make you feel out of it and less able to pay attention.
Waking up well-rested is an amazing feeling because sleep also gives the opportunity for the body to heal and regenerate. Many times when you feel sick or are injured, you simply try to go to sleep and hope to feel better in the morning. And it often happens, since the body is able to recover and heal without having to use energy on the other things which come up during the day.
Finally, it helps to provide emotional stability. Areas of the brain that regulate emotion, such as the amygdala and the hippocampus, show increased activity during sleep. This allows these areas to regenerate and be more prepared to react to situations in the future. Without sleep, we may be more prone to overreact and create issues that aren’t necessary.
Clearly, there are a ton of different processes that make sleep important. Although we still don’t have one overall explanation, one thing that’s completely certain is that sleep is an extremely important part of our lives!