Sleep is an essential biological process shared by all sentient beings. This includes animals that do not ‘lie down’, or stop moving, to sleep, such as marine mammals and fish. Dolphins continue to swim while sleeping, literally ‘switching off’ one side of the brain at a time. Birds sleep while still perched in trees, and many animals also sleep standing up. They may not look like they are sleeping, but they are, because they would die if they didn’t. As would we. Humans need to sleep is as fundamental to life as is air, food and water. Now, let’s focus on humans, and human sleep…
The biological role of sleep for healthy bodies:
We may not be aware of what goes on when we sleep, other than dreams we remember, but there’s a lot happening. Several biological processes occur during sleep, that are essential for:
- cell /tissue rejuvenation, replacement and damage repair
- generation of new cells and tissue
- hormone synthesizing
- metobolic processes
This is why babies (and growing teenagers) sleep so much, and why we need less sleep as we get older (as the rate of tissue repair and replacement, need for hormones and our metabolism all slow down).
The physiological role of sleep for healthy minds:
Our brains take in huge amounts of information when we are awake; far more than you are consciously aware of from the environment, as well as all the things we consciously learn and think about. Sleep gives our brains time to process that information. This is why we dream. Dreams are ‘symptomatic’ of our very busy (sleeping) brains.
Sleep gives us ‘time-out’, but the exhaustion that you feel when you don’t get enough sleep is not psychological. It’s only experienced that way. Exhaustion is your body (including your brain) deteriorating. This happens as it cannot repair tissue, maintain hormonal balance, metabolise on a cellular level, or create new neural networks to process information. Luckily, a good nights sleep (or 3) will make up for a few late ones! It’s prolonged sleep disturbance that can seriously affect health and wellbeing.