Sleeping longer leads to decline in brain function

On May 8th, 2015, Posted by Essayadmin No Comments

Ah those pillows, that bed! How many of us love to spend hours sleeping and waking late? Yes, I am sure many of us are sleep lovers. But, alas, we may have to curtail our precious hours spend cuddling and snuggling in bed. In essence, too much of anything is bad for health. So read on and find out about the causes, the dangers and the effects of oversleeping on your brain.


Firstly, let us try and understand what sleep is. When we see a sleeping person, we naturally assume that everything in that person has gone to sleep. But it is not so, the brain is always active, exerting control over the vital body activities.

There are chemicals in our body which sends signals to the brain, leading to drowsiness or alertness as the case may be. Our sleep is also a time of complex brain activity, with several phases of sleep reflective of different levels of body activity.

What is the relationship between sleeping and the brain?

Sleep serves as a cleansing agent, as some kind of natural soap i.e. it provides a mechanism by which the waste products from the metabolic activities in the brain cells and toxins are cleaned up and removed.

A group of scientists at the University of Rochester have demonstrated through their experiments in mice that during sleep, there is an extra pumping of cerebro-spinal fluid around the brain, which swipes away the toxic substances which would otherwise accumulate and cause problems. This is facilitated by the shrinking of the brain cells during sleep, thus enabling the CSF to flow more around these cells.

So, while sleep is necessary for our health and there seems to be strong evidence in this favour, excess of sleep may not do us good. Previous reports on the optimum duration of sleep required was around 7 to 8 hours and now there seem to be good reason to confirm this.

Why oversleeping is bad for the health and especially for the brain?

Oversleeping can occur in response to fatigue and stress and is not uncommon but oversleeping can also be associated with disorders. Oversleeping is associated with diabetes, heart disease and increased occurrence of death, on account of depression and low socioeconomic status.

It is also a sleeping disorder for some, caused by hypersomnia , where the person experiences severe sleeping fits through out the day as well as long sleeping periods in the night. Oversleeping can also be induced by disorders such as obstructive sleep apnea which leads to interruptions in breathing during sleep. This disorder leads to an interruption in the sleep cycle and hence to an increased demand for sleep.

Use of certain substances such as alcohol and some medications can also lead to oversleeping. What does oversleeping lead to? It has been associated with fatigue, tiredness and headaches, amongst other things. And it does not just stick to thats. Oversleeping can have far more consequences on the health, that you can think of.

Research reports indicate that lack of sleep may cause impairments in memory, shrink the brain and increase stress levels. Those who are particularly vulnerable to this include nursing mothers, shift workers, airline crew etc.

However, if you thought that sleeping longer would compensate this, you are wrong. Oversleeping has no benefits. The reason being, recent research reports have indicated that longer sleep hours may not be exactly good for your brain. In fact, it may lead to sharper decline in its cognitive function, which means that your thinking and remembering ability sharply deteriorates.

The study of more than three years duration, shows that elderly patients who have been sleeping for around 9 hours in a day, show faster decline of cognitive ability as compared to those who slept for six hours or less hours. What is more alarming is that the oversleeping population accounted for a large portion of the study respondents while the normal sleepers accounted for 49 % and 11 % accounted for five hours or less.

The amount of cognitive decline suffered by these sleepers was more than thrice the amount of that suffered by the normal sleepers. This sign is amongst the symptoms for onset of dementia and hence is worrying. The difference in the amount of decline was significant enough to warrant concern about long sleeping hours. Researchers also pinpoint the effects of oversleeping leading to headaches as due to the effects on the levels of neurotransmitters such as serotonin.

University of Tubingen research scientists point on the connection between oversleeping and depression. Brigham and Women’s hospital pointed to the fact that those who slept nine hours or more had damaged brain function and that the symptoms of Alzheimer’s was more advanced.

In fact an old study on 2011, finds that your brain can age by as much as seven years by oversleeping. The research has shown that people oversleeping scored less on tests in reasoning and vocabulary as compared to average sleepers.

However scientists have warned about taking these results as a 100 % definite and more studies need to be conducted to verify this. It could be also possible that longer sleeping is related to ageing which then leads to decline in the quality of cognition. Hence more studies need to come out.

In the meantime, while more results come out, do ensure that you DO get your daily minimum requirements of sleep of around 6 to 8 hours, and give your body and brain, that well needed rest and rejuvenation.

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