Sleep Part 1: Understanding Why and How We Sleep
We all know sleep is important for our productivity - a good night’s sleep will increase alertness and arousal and make us perform better. Here Sasha Dworkin uses her expertise in neuroscience to look at how important sleep is - and how we do it.
So Why Do We Sleep ?
Precisely why we sleep has never been definitively agreed on, but two well supported ideas are:
Restoration and Repair - There is evidence that some genes - which are only switched on when we are asleep - are linked with restoration processes in the brain. Sleep deprivation has also been linked to higher rates of infection.
Memory Consolidation - A number of studies have shown that sleep deprivation inhibits learning and memory as shown by performance in different memory tasks. There is also evidence that sleep boosts creativity and finding novel solutions to complex solutions. Although we are not sure of the exact mechanism of memory consolidation, studies in the hippocampus, (where short-term memory is stored) have shown that sleep strengthens the synaptic connections between brain cells and the memories are transferred to other parts of the brain.
So How Important Is It?
As well as the effect of sleep on learning, memory, creativity and normal restoration, the importance of sleep has been highlighted by links to pathology:
Rotating shift work is a great example of sleep disruption - people on shift work have to ignore the light/dark cycle and their own natural circadian rhythms and often do not have enough time to adjust to one sleeping pattern before they have to change it again. Rotating shift work has been linked to a number of cancers, and cardiovascular disease and was recognised as a “probable carcinogenic” by the World Health Organisation.
What Makes Us Sleep?
Light is the main entrainer of our circadian rhythm which allows us to have a regular sleeping pattern. Our sleeping patterns are regulated by the secretion of a hormone in the brain called melatonin which essentially tells our brain to go to sleep. Melatonin secretion happens when we are asleep and is suppressed by light signals conveyed from the suprachiasmatic nucleus - our master clock in the thalamus.
Sleep is hugely important - not just for our productivity and attention but for our health. With all the current research available, it is both ineffective and irresponsible to replace sleep with work as a long-term measure. We are living in a time of sleep deprivation and need to start giving sleep the respect and consideration it deserves.
So use your brain - get enough sleep so you can... use your brain some more.