Each night, we abandon our companions, our work and our play so that we can sleep. It is a bodily function that we have only limited control over– sure, we can postpone our sleep for a little while, but eventually it overwhelms us. We spend roughly one-third of our lives sleeping and one-quarter of that time we spend dreaming. Sleep is essential to our lives and prolonged sleep deprivation, causing sleepiness, is devastating to proper functioning.
How Does it Work?
Our sleep cycle or circadian (circa – meaning approximately and dian – meaning one day) rhythm, is significantly related to our cognitive performance (ability to think), as well as our mood. Our sleep cycle is predominantly dictated by environmental factors, such as light and meal times, allowing us to anticipate and prepare for the challenges and opportunities that day and night present.
Sleep is a basic biological process that allows us to organise more complex functions, such as thinking and learning. Specifically, sleep allows our brain to ‘mature’ and consolidate memories, and also allows us to remain alert and ready to learn throughout the day.
A little bit of interesting information about sleep and our memory…
The sleep process allows us to consolidate both declarative and non-declarative memories.
- Our declarative memory is where we store information about events, facts and general knowledge, and providing we know how to organise this information well, we can access it on demand.
- Non – Declarative memories are ones that are only available for ‘subconscious’ to access, and typically include information about procedures, such as how to ride a bike.
So, we need sleep to remember remember the knowledge that we have acquired throughout a given day and to learn or recall how to complete a task (and transition from novice to expert). We are able to strengthen new connections much more efficiently when we are asleep as opposed to when we are awake. You see, sleep reduces interference to the development of new connections in our brains.
Studies have demonstrated that sleep allows our brain to maintain a ‘bigger picture’ perspective. This means that we are less likely to get caught up in small details that we can’t control, reducing our experience of worry. In addition, if we have slept well, we are more capable of effective problem solving allowing us to stay calm and rational at challenging times.
So, What is Good Quality Sleep?
Research has been debating this for a long time – it’s hard to say, because there are so many different stages of sleep, and we’re still exploring what happens in each stage. One thing that science agrees on of course, is that sleep overcomes sleepiness.
We become sleepy for two main reasons:
- Being awake for too long – the longer we are awake, the greater the pressure for us to sleep, and this pressure is only alleviated by sleeping;
- Our internal clocks – we all have an automatic circadian rhythm, which is a subconscious ‘clock-like’ system that regulates our alert and sleep states.
What happens when we’re sleepy?
- Our mental and emotional states decline with prolonged wakefulness – so the longer we are awake, the more our capacity to think and manage our emotions is reduced.
- Specifically, our thinking skills are affected after just 30 hours of no sleep, by a decrease in our verbal fluency, creative thinking and nonverbal planning.
Research suggests that normal requirements for sleep vary widely among adults, from about 5 – 10 hours per night, where the average length is about 7.5 hours per night.
Tips for ensuring that you get a good night sleep
- Try to exercise daily for 20 – 30 minutes
- Take the time to learn to relax. Ask a psychologist for some help with this, or try a meditation class.
- Have a relaxing bedtime routine, like have an herbal tea, read for 20 minutes and then lights out.
- It’s important to avoid caffeine and sugar before bed, and try to avoid going anywhere near a screen in this routine – the light will interrupt your preparation for sleep.
- Set aside some time to think about your worries each day (30-minutes maximum), so that you can get it out of the way before you have to go to bed. Do this outside of your bedtime routine so that you can be present throughout the day, and remain calm before sleep. Making a note of your worries as they come up throughout the day or before bed, to review at the allocated time is a helpful strategy. Have a look in our resources library for a helpful sleep diary!
- Buy a comfy mattress, pillows and blankets, try to make your bedroom as dark as possible and ensure that you’re sleeping at a comfortable temperature.
- Try not to use your bedroom for work – let it be your restful sanctuary.
Bernier, A., Beauchamp, M., Bouvette-Turcot, A., Carlson, S., & Carrier, J. (2013). Sleep and cognition in preschool years: Specific links to executive functioning. Child Development, 84 (5), 1542 – 1553.
Charalambos, K., & Hastings, M. (2010). Circadian clocks: genes, sleep and cognition. Trends in Cognitive Sciences, 14 (6), 259 – 267.
Deak, M., & Stickgold, R. (2010). Sleep and cognition. WIRES Cognitive Science, 1, 491 – 500.