Extreme sleep: Change in durations may affect brain health in later life

A new research study led by Brigham and Women’s Hospital (BWH) published in The Journal of the American Geriatrics Society in May, shows an association between midlife and later life sleeping habits with memory; and links extreme sleep durations to worse memory in later life. The study suggests that extreme changes in sleep duration from middle age to older age may also worsen memory function.

“Sleep Duration In Midlife and Later Life In Relation to Cognition: The Nurses’ Health Study,” led by Elizabeth Devore, ScD, instructor in medicine in the Channing Division of Network Medicine at BWH found that women who slept five or fewer hours, or nine or more hours per day, either in midlife or later life, had worse memory, equivalent to nearly two additional years of age, than those sleeping seven hours per day. Women whose sleep duration changed by greater than two hours per day over time had worse memory than women with no change in sleep duration.

This study was the first to evaluate associations of sleep duration at midlife and later life, and change in sleep duration over time, with memory in 15,263 participants of the Nurses’ Health Study. Participants were female nurses, aged 70 or older and were free of stroke and depression at the initial cognitive assessment.

“Given the importance of preserving memory into later life, it is critical to identify modifiable factors, such as sleeping habits, that may help achieve this goal,” Devore stated. “Our findings suggest that getting an ‘average’ amount of sleep, seven hours per day, may help maintain memory in later life and that clinical interventions based on sleep therapy should be examined for the prevention of cognitive impairment.”

Specifically, researchers report that:

  • Extreme sleep durations may adversely affect memory at older ages, regardless of whether they occur at mid-life or later-life.
  • Greater changes in sleep duration appear to negatively influence memory in older adults.
  • Women with sleep durations that changed by two or more hours per day from midlife to later life performed worse on memory tests than women with no change in sleep duration, equivalent to being one to two years older in age, compared to those whose sleep duration did not change during that time period.

“These findings add to our knowledge about how sleep impacts memory,” said Devore. “More research is needed to confirm these findings and explore possible mechanisms underlying these associations.”


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91 thoughts on “Extreme sleep: Change in durations may affect brain health in later life”

  1. I have learnt a lot about the above article since I did not know how much effect our sleep has on our daily behavours and how important it is that we stick to one sleeping time slot and obviously have enough sleep. Though I think we all have our own sleeping preferences just as it is mentioned above about others being able to sleep for long hours whilst others are able to sleep for shorter hours.An informative article indeed.

  2. Sleeping is a good thing, it relaxes the mind and the body. But its true that too much of anything is dangerous. Now I understand why most of the people who suffer from Alzheimer is the old age.

  3. Although I find this article interesting to read and I agree on the fact that we need at least 7-8 hours of sleep per day, I still think that this is not the only reason for memory loss and that this information is not very valid on the entire human race because it was only tested on one gender and it was also only tested on nurses. Shouldn’t it also be tested on people in other lines of work? Just to take into consideration that different jobs have different stress levels and working hours and many other factors, which I think can also play a part in memory loss and can differ from person to person, according to how much sleep each individual needs to function the best. Noted though to get enough sleep anyway.

  4. Sleep is very important and the amount as well .The research done by Brigham and Women’s Hospital is a good basis to infer a conclusion of how sleep effects one’s memory.With any experiment or data analysis one has to consider other factors which can contribute to the effect .When looking at people’s sleeping patterns and how it effects people’s memory loss in older age ,you also have to keep in mind that there are other factors which lead to memory loss.The person’s life style ,how often they exercise , their socio-economic status ,their relationships as well as sleeping patterns should be taken into consideration when making a generalised statement.
    We are all different and have different meals and different sleeping patterns.What is to be said of people who take naps during the day ,or people who have a 3 hour sleep and then a 4 hour sleep later on .Are these people part of the ‘at -risk’ class for memory loss in older age ? In conclusion as you get older you become more prone to age related conditions ,such as dementia , amnesia ,depression and many more which could be stress related and influence memory ability.There is no determining how much sleep you need but it is clear that people need to know that sleep and the amount of time you sleep could influence you,either now or later in your life.

  5. Though change in sleep duration may be due to change in lifestyle. I do however agree that 7 to 8 hours of sleep is the recommended duration but in order to keep a fit mind, brain-stimulating activities like reading are necessary in decreasing the development of cognitive impairment.

  6. This study constitutes the first step towards conducting further studies to test the association between cognition and extreme sleep duration (both too little and too much) or changes in sleep duration (exceeding two hours). It is unclear whether all aspects of cognition—memory, comprehension, language production, calculating, reasoning, problem solving, and decision making—were tested, or merely memory that is one aspect thereof. The sample group only included women.
    As Devore correctly states these findings need to be confirmed, preferably by means of a prospective study to prove a cause-effect relationship between sleep duration and cognition in general or memory in particular.
    Such a prospective study would entail instructing the study participants—both men and women—to sleep a specific number of hours, and testing their cognition periodically over years. However, reliance on the recordkeeping of participants constitutes a risk in that sleep patterns can be inaccurately reported, as is potentially also the case with the current study. Further, the controlling of confounders needs to be factored in to ensure that variables—genetic, physiological (illnesses), psychological (stress/trauma) and environmental factors; diet; mental, social and physical activity (exercise) impacting on cognitive processes—are controlled. It is unclear whether these confounders were taken into consideration in the current study.
    Given the global epidemic of dementia with the increasingly ageing population, this study has made a considerable contribution and should be investigated further.

  7. I do not entirely agree with the article, since it only focused on one gender and one cause of memory loss – sleep patterns.

    Sleep patterns are not the only factor contributing to memory loss. Memory loss can be minimised through the following methods:
    Learning new traits and skills; physically active lifestyle; well-read and informed about new developments in society; eat a well-balanced diet and social support of loving family and friends.

    The experiment would be more accurate if it was tested on both men and woman; people of different ages and different careers. By doing the experiment on a broader scale the results would help us immensely to understand a more precise cause of memory loss. By researching all the various factors a more truthful solution would be found.

  8. This is a very interesting article and I was very surprised to see that quite a bit of research has been conducted on how sleep patterns affect physiology and psychology in humans. I’m sure everyone is aware that sleep affects how they perform on a day to day basis, when we don’t get enough sleep even simple tasks can be more difficult. I think it is very interesting that you sleep patterns in mid-life can possible affect your memory in later life. I think further testing and research should be done on this concept as conclusive around the board results would be very beneficial to society as preventive maintenance and this study is too specific to be accepted as around the board truth. Although this information is interesting and possibly helpful sleep is a very circumstantial aspect of live no person can maintain consistent sleep patterns as sleep is affected by so many factors.

  9. I agree with the article’s point of view because as a person increases his/her sleeping duration, his/her brain functions less as it rests for that certain amount of time thus leading to certain effects such as memory loss occuring more frequently than when he/she was maintaining his/her sleeping duration as the brain then was used to function more at an extended period while it was given less time to rest.

  10. This is an interesting concept whether sleeping are directly responsible for decline in memory. There are several problems with this experiment- It was only done on women in midlife, do we know the women was of the same intellect, how was the intellect established and tested in later life, was texts done in the same time in ministerial cycle. All these and more can affect the results. There are several reasons for the decline in memory and were all of them part or excluded from this experiment? There are also lots of reasons way people sleep less and more thus like extreme work load of loss of loved ones – emotional trauma est. Can it not be these factors that are responsible for the decline in memory and not the amount of sleep? This is however a very small step in understanding way our brains and memory decay at different rates.

  11. This is not very surprising due to the fact that a sizable portion of a person’s life is spent sleeping. This article reinforces the idea that sleep is when the body and mind recovers from the trials of the day. Due to sleeps large impact on the recovery of the body and mind it was undoubtedly linked to the maintenance of memory and physical rejuvination.

  12. This not very surprising considering that a sizable portion of a person’s life is spent sleeping. This article reinforces the idea that sleep is how the body and mind recover from the trials of the day. By interrupting the basic repair function of the body and mind this would undoubtedly lead to decreasing efficiency of memory and increasing fatigue of the body.

  13. This research has got me thinking, does the changes in sleeping patterns affect those that are younger than the average middle aged? Because changes in sleeping patterns occur way before people hit middle age, so the changes may not be because of the change in sleeping patterns of the elderly, but because of the keeping patterns of when theybwere younger?

    Sleep has always been an important part of growing up, since when you sleep, your body has time to rest and repair, so it makes sense that changes in sleeping patterns could affect the mind.
    The changes in sleeping patterns of those older than myself could change due to many reasons, and because people are so different it is difficult to pinpoint the exact source of the problem, but this research is a step in the right direction.

  14. It was shocking to read how a few hours more or less sleep could influence one’s later life so much, especially as I have very extreme changes in sleep duration. But I found the article unrealistic as it is impossible for one to sleep exactly seven hours a day. If one has work to do, it is essential to decrease one’s sleep duration by a few hours and during weekends, he or she will want to catch up on the sleep hours lost. Sadly, the current society and the system in which we live by does not allow such leisure for us to sleep seven hours every day. However, I think further studies should be done so that more people can become aware of the liabilities we are imposing on our brain and try to make realistic changes to protect the memories of future generations.

  15. This article is intriguing as it extends our fundamental knowledge that an adequate amount of sleep is essential. Although the research conducted in this article was done at a women’s hospital, it would be interesting to know how sleeping patterns affect men and whether there is a direct correlation between how memory of men are affected in comparison to women.

    Adding to Mellisa Geldenhy’s(14227755) answer on why too much sleep is bad for you: A study conducted in 2011 by University of London researchers exhibited that it is possible age your brain by up to seven years by getting to much or too little sleep. If you sleep too much, your body will become accustomed to getting more sleep then required and as a result will constantly feel tired.This can lead to a physical and mental decline.

  16. Due to what we see happening to our grandparents one ca really agree to the fact that change in sleeping duration really affect memory in old ages. It turn out that when a person grow old they prefer sleep less ours than most people usually do and this seems to really affect their memory badly.

  17. One of the most pressing questions of our time is “how do our brains work ?” This study is just one of many in which our behavior and habits are studied to determine what effect it might have on our brain activity and our capacity to retain information.

    This particular study uses a selective group of nurses with particular sleeping habits and routines and then studies the impact it has on their memory later in their live span. The use of nurses as a study group allows for variation across the group because nurses work difficult hours and their routines are often unsteady.

    During the study only the sleeping habits of women in their middle ages where taken into consideration. My question however is if a change in you sleeping patterns in you childhood or early adolescence has an impact on your memory as you grow older ?

    This study may present important insight to the way we convert information into memory which may further lead to the understanding of the working of our brains.

  18. From the post we are given the understanding that the process of aging affects the quality and quantity of sleep. It’s interesting to note that this article helps to disprove the common misconception that adults simply don’t need as much sleep. Good sleep habits help balance biological factors that make it harder to attain healthy sleep as we grow older. We are able to assume that sleep habits impact our cognitive abilities, especially in the elderly, which can have a ripple effect and can compromise their quality of life.

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