Why Is Sleep So Important?

You can take it as a fact that sleep and sleep patterns have an impact on brain function and health. Most of us can attest to that from personal experience. When we have a bad night’s sleep, it is very difficult to function the next day.

But, there is a bit of a chicken and egg symptom with sleep. Poor sleep can impair cognitive functioning. As well, the majority of individuals who are challenged by dementia experience sleep problems.

So, which comes first – the sleep problems or the disease?

Or are they somehow linked to each other?

Recent research is giving us some interesting insights into the importance of sleep and sleep patterns.

Sleep Quality

Sleep is not a straight-forward experience. Sleep has a set of patterns to it and each of those patterns plays a role in overall brain health. One part of the sleep pattern is referred to as REM sleep, or ‘rapid eye movement’ sleep. It is characterized by random movement of the eye and the tendency to have vivid dreams.

This part of sleep is also associated with memory consolidation. During REM sleep, your brain is consolidating the memories from the previous day and storing them in the appropriate parts of the brain. If REM sleep does not occur or is interrupted, the brain will not have properly stored the memories. Depending what those memories were, the individual may find that their cognitive functions are impaired the following day.

Another interesting aspect of sleep is the work of the brain’s glymphatic system during slow wave or stage 3 non-REM sleep. During this time, the amyloid in the brain is disposed of or ‘cleaned’ out of the brain. If an individual is not getting sufficient amounts of slow wave sleep, the amyloid may not be getting adequately disposed of. And we know that amyloid build-up in the brain is a factor in Alzheimer’s disease.

So certainly, quality of sleep has an impact on brain health.

Sleep Quantity

Quantity of sleep is also indicative of problems with brain health. Individuals who sleep ‘too much’ have a higher association for developing Alzheimer’s disease.

A recent study looked at quantity of sleep and the risk of developing Alzheimer’s disease. The study established a link between individuals over the age of 65 who sleep more than nine hours a day and Alzheimer’s risk. What is not clear is whether increased sleep is a risk factor for Alzheimer’s or an early indication of Alzheimer’s disease.

It may be that brain function is becoming impaired and the brain is ‘sleeping’ more.

We do know that increased sleep beyond the norm is correlated with depression. And there is a correlation with depression and dementia in individuals over the age of 65.

Practical Applications

How should you react to changes in sleep patterns or difficulty sleeping?

First of all, create a positive sleep environment.

You can do that by ensuring that you are practicing good sleep habits. Good sleep habits can have a positive effect on sleep quality.

1. Get sufficient physical and mental activity during the day will help the brain and body come to the end of the day pleasantly tired. This will aid in improving quality of sleep.
2. Creating a sleep routine can also have a positive effect on helping the brain and body prepare for sleep. Cuing the brain that it is time for sleep by creating a bed-time routine is also helpful. You may choose to take a warm bath, have a warm non-caffeinated drink, or use a favourite hand cream before bed, signalling to your body that it is now time for sleep.
3. Having a fixed time to go to bed will also help create a positive sleep routine.

 

Secondly, if sleep patterns change consult your family doctor. This could be a warning flag that something is amiss. Vitamin deficiencies could be a culprit and you may need supplementation to help you re-establish good sleep patterns.

Finally, be aware that changing sleep patterns could be indicative of depression. Depression, particularly in individuals over the age of 65 has been linked to increased dementia risk.

Conclusion

While we do not have definitive evidence linking sleep disruption as a contributing factor to dementia, there is enough evidence to see sleep disruption as a flag.  Focusing on improving sleep will positively contribute to brain health, regardless of age and level of cognitive impairment. And a healthy brain has greater coping skills for whatever life throws your way.