Sleep is composed of physiologically and neurochemically distinct stages. Sleep stages are divided into rapid eye movement sleep (REM) and non-rapid eye movement sleep (non-REM). During your sleep your brain has time to strengthen memories and improve their resistance to interference. In addition, sleep contributes to the process of gaining insight, making mental connections, and integrating large amounts of information. On the other hand, an ongoing lack of sleep or poor-quality sleep increases your risk of health problems such as cardiovascular disease, high blood pressure, diabetes, depression, and obesity. They are also linked to memory problems, forgetfulness, and more falls or accidents.
There is a generally agreed upon consensus that insufficient sleep can lead to a general slowing of response speed and increased variability in performance, particularly for simple measures of alertness, attention and vigilance. Meanwhile, there has been some variable data regarding the effects of sleep deprivation on many higher level cognitive capacities, including perception, memory and executive functions. A recent article in Scientific American examined recent research about sleep deprivation and how it appears to shut down production of essential brain proteins due to a deficit in molecules needed for neurons to communicate efficiently.
The extent to which sleep deprivation affects a particular cognitive process may depend on several factors, including the magnitude of global decline in general alertness and attention, the degree to which the specific cognitive function depends on a certain emotion-processing network, and the extent to which that cognitive process can draw upon associated cortical regions for compensatory support.
Another study, published on October 31 in Science, a team of researchers investigated how cerebrospinal fluid (CSF) flow can change during sleep and how this might relate to alterations in brain blood flow and electrical activity. The researchers wondered if CSF may flush toxic waste out essentially “cleaning” the brain and if this clearance is moreso during sleep. The findings may have implications for neurodegenerative diseases, which are thought to be caused by build-up of toxic proteins in the brain, such as amyloid-Beta in Alzheimer’s disease.
Researchers have suggested that we aim for 7-9 hours of sleep each night. Here are some tips that may be helpful:
Go to bed and wake up at the same time every day, even on weekends.
Find ways to relax before bedtime each night. Avoid distractions such as cell phones, computers, and televisions in your bedroom.
Exercise at regular times each day, but not within 3 hours of your bedtime.
Don’t eat large meals, or drink caffeine or alcohol late in the day.
Avoid long naps (over 30 minutes) in the late afternoon or evening.
For more information about obtaining quality sleep and its impact on your brain as we age you can check this page from the National Institute of Aging.