By Dr Fiona Kerr Founder/CEO The Neurotech Institute
Our sleep needs
We need different amounts of sleep at different ages. Babies’ brains are extremely busy building, reorganising, differentiating, consolidating learning, so they sleep much of the time. A 2-year-old still needs 14 hours for brain development and socialization, and a 9-year-old up to 12 hours. Teen brains are very busy physically pruning and rewiring many emotional and task areas and need 9 hours, which they seldom get thanks to technology, caffeine and a 2-hour shift in melatonin that keeps them awake late evening and asleep when they need to get up for school, leaving them permanently sleep deprived (hence sleeping all weekend). Young adults’ brains recover well from inconsistent sleep and weekend top-ups, but by 40 we are less flexible and normally need 7-8 hours regularly. Older people have brain changes that can cause sleep to be more fragmented, often worsened by medications and lack of exercise. Luckily, they are often able to nap when they feel tired, especially that all important midday nap which we are designed to have.
What happens when we sleep?
When we sleep our brain is very busy doing the things it cannot while we are awake. Our brain carries out maintenance, files information and learning from the day and creatively rearranges our encoded data in later sleep stages. Whole brain networks change how they communicate and interact while we sleep. Early sleep appears richer in carrying out maintenance such as cleaning up sticky plaque in the brain and lowering blood pressure and respiration (we know that chronic long-term sleep loss speeds up cognitive decline). In pre-REM 2 we file and consolidate learnings from the day, and REM sleep is associated with memory consolidation and dreaming, as well as emotional regulation of anxiety, depression and resilience. Recent studies show lack of sleep negatively influencing emotions and empathy and can increase anger or reactivity. Sleep deprivation, alcohol, cannabis, many antidepressants, or some sleeping pills all cut down REM sleep. Increased creativity occurs in later stages when different chemicals are released to target memory consolidation, plasticity and even growing new brain (neurogenesis). The brain shuffles and recombines information and creates new ideas or answers in a state called abstraction, which is why we wake up with a new idea or decision – sleep on it really works!
Getting to sleep
Our brain loves patterns, the basis of habits. Sleep hygiene is about ensuring basic comfort such as feeding the senses – hot milk, a relaxing shower, a good mattress, comfortable bedclothes that smell and feel inviting (weighted blankets can help some people sleep longer, especially with physical conditions that interrupt sleep). Creating these habits will cue your brain and body to start releasing what you need to induce sleep. Controlling light exposure, both natural and artificial, stimulates cycles and chemicals to come on and turn off at the right times, including melatonin which is signalled to be released earlier in the evening when your eyes are exposed to natural early morning light. We know that screens in the mid to late evening disrupts this (not just blue light, so filters help but don’t stop the problem – just stop looking at them). Even dozing in front of tv, light through your eyelids is still processed by the brain, causing fragmented sleep and arousal of brain waves and heart rate during the night. Other activities include getting exercise during the day, writing down any worries or things to do, then picking up a book until sleepy, preferably fiction that allows you to escape into imagination.
Returning to sleep
Easy to say, it is important not to lie there stressed if you wake during the night. Try and relax with your eyes closed, knowing that your brain and body are still getting many lovely benefits from this rest. Don’t pick up a screen which will increase hypervigilance (arousal) and alertness – pick up a book instead if you want to read. If you become anxious, some practitioners suggest getting up to stop bed having a negative association, but make sure you don’t create a learned habit of waking and getting up. Spending too much time in bed can also undermine sleep at night, so explore different methods to find out what works best for you. Other disruptive habits are a mix of coffee during the day and relaxants at night such as sleeping pills – if you use these combine them with other forms of treatment including behaviour therapy to minimise them as some important brain processes are blocked when tranquilized, and many types are addictive.
Relaxation, meditation and daydreaming
Daydreaming is our natural cognitive state, technically called our default mode. When daydreaming and meditating we go into abstraction, a state of mind that is essential for deep thinking, concept building and new ideas – the basis of the Aha moment. When not driven by task needs, our brains can roam, cross-reference, increase creativity, unearth insights, hone our intuition and solve problems differently by lengthening and broadening our viewpoint to think longer term. Reflection (including meditation) also lets us look inwards more, getting in touch with who we are, and learning to accept ourselves with calm. And the good news is the more we do it, the better and more creative we get. Unfortunately, abstraction is stopped by distraction (which tech designers know well, designing for maximum stickiness through dopamine laden colour and movement), so if you want to let your brain riff to create, solve problems, reflect, rest, think differently, don’t turn to your screen – Turn it off and look up for many more lovely chemicals, mental time out and great ideas!