Everyone is familiar and happy with the concept of a “memory”, but how many of us are aware of the importance and significance of a “forgettery.” This is a relatively new idea, and we have got some evidence emerging that sleep is hugely important for both.
There is a useful analogy that can explain this a bit more. If you imagine that the inside of your head is a busy office, and that every thought that you have during the day generates a piece of paper in that office. During the course of a day we have many, many thoughts, about everything and anything. Some of those things are important, or even very important (e.g. I need to call the mortgage adviser), but other thoughts may be less so (e.g. which socks shall I wear today?; Ooh – look at that dirty car). But each of these generates a piece of paper. Then we sleep and our secretary (the hippocampus) comes into the office and starts to organise things. This organisation consists of sorting through all the paper and throwing out the rubbish (socks / dirty car); and prioritising the important things (sticking the “call the mortgage advisor” piece of paper on top of the in-tray for tomorrow morning) i.e. encoding this into the cortex as something to be remembered and not forgotten.
If we sleep well we will do a good job of organising our office and it will be tidy again by the morning, if we do not sleep well then the office will be a mess in the morning – this idea has important implications for our mental health.
The implications of this are very significant for all mental health conditions. How we think and feel not only affects our waking lives, but also has a significant impact on our sleep, especially our ability to initiate and maintain the sleeping states. There has long been an established link between a large number of mental health conditions and poor sleep. In fact, one would be hard pressed to find anyone living with an enduring mental health condition who does not have a concomitant sleep problem. Mental health conditions and insomnia almost universally seem to come hand-in-hand, with insomnia being a core diagnostic feature of many mental health conditions.
To expand and taking depression as an example of this: we know that people with depression are prone to a certain thought processes that are involved in the development and maintenance of the condition. These are referred to as “cognitive bias” and “selective attention.” Depressed people will tend to focus on negative situations or stimuli more than on more positive or neutral situations or stimuli (selective attention), and they will tend to see situations as more desperate then people who do not suffer from depressive symptomatology (cognitive bias). These two phenomena interact and, over time, can contribute to the maintenance and increasing severity of a depressive episode; and so lead an individual into a persistently and deeply depressed state of mind – major, clinical, unipolar depression. This process is almost always accompanied by poor sleep and, as mentioned above, insomnia is a core diagnostic feature of major depression.
If we reflect briefly on the section above on memory and schemas where we introduced the analogy of the sleeping brain being a cluttered office which is being “tidied” of superfluous information. If our sleep is disturbed then this “clutter” is not being fully cleared away before we awaken in the morning, leaving us feeling discombobulated with an “untidy” office still in need of some spring cleaning.
So if mental health conditions can be seen as a disorder of memory, and if memory is schematically organised, driven and arranged; then sleep, which has such a pivotal role in that schematic organisation and arrangement, must be regarded as fundamental to the maintenance of our mental health, whether that be healthy or poorly, and everywhere else in between.
Poor sleep is a very common experience and certainly is linked to stressful life events, such that 1 in 4 of us may experience insomnia at a clinically diagnosable level at some stage during our lives, and that poor sleep may then have further negative consequences for our mental health. Treatment options are available with Cognitive Behavioural Therapy for insomnia (CBTi) being the NICHE (National Institute for Health and Care Excellence) primary recommended treatment option.
If you or someone you know is having trouble with their sleep, then please do contact us for help and advice.
If you are a healthcare professional working with clients whom experience sleep problems and are interested in training in assessing and treating your clients using CBTi then we are providing training in this important and often neglected area of behavioural sleep medicine across the UK in 2019 and beyond, please contact us or visit our website for more details.