One of these is hypoxia, a condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level. Hypoxia occurring at night can be an independent risk for brain problems at any age, but certainly at older ages when sleep-disordered breathing (link to Gazda SDB blog) can become more and more common. Our “part 1 sleep blog” discusses in great detail the issues of sleep apnea and sleep fragmentation so we encourage you to also review the information there.
Your brain at rest.
As you sleep, your brain works to solidify memories that you formed throughout the day. It also links these new memories to older ones, helping you make neural connections between different pieces of information that form the basis of comprehension, memory, enable critical thinking skills, conceptualize new ideas and more. Sleep is also a time when the brain’s waste disposal department (the glymphatic system) gets going to essentially clear out all the toxins and debris. Two types of cells, microglial cells and astrocytes, perform this cleaning process. During sleep, microglial cells help remove a toxic protein commonly found in the brains of Alzheimer’s disease patients called beta-amyloid. The astrocytes prune away unnecessary synapses and repair the brain’s neural wiring.
Sleep has an interesting architecture and is critical for memory consolidation... so be sure to get some sleep before your finals or work presentations! Our typical sleep cycle can be 8 to 9 hours long, and is divided mainly into two stages: NREM/early night sleep, and REM/late night sleep. Our brain is still active during all stages of sleep and engages in cognitive activity, so we never really lose consciousness completely. When it comes to memory consolidation, each sleep stage is responsible for a certain type of memory.
Without the benefit of sleep for our built-in cleaning processes to clear the way to perform complex tasks, we cannot expect to function at our peak level. And worse, we know that lack of sleep on a repeated basis can contribute to cognitive decline, impaired immune systems and possibly set the stage for neurological and other disease initiation.
Sleep smarter, sleep better.
No doubt you already know the recommendation to get 7 to 8 hours of sleep per night – that’s not the problem. The problem is actually achieving that number as often as possible. Of course, the last thing you want is to stress about not sleeping! Stress is a large contributor to your current lack of quality rest - even before the last few months, the CDC reported that 35% of adults get fewer than 7 hours of sleep per night. So if you’re having trouble getting a good night’s sleep, consider these healthy sleep hygiene practices to include in your routine:
-Limit napping to 20 minutes - really! As tempting as a two-hour nap on the sofa may seem, limiting your nap time will help with nightly sleep patterns.
-Avoid caffeine and nicotine close to bedtime. (Best to avoid nicotine entirely, of course.)
-Exercise regularly, but preferably not too close to bedtime. If the only time of day you can fit in a workout is in the evening, stick to something like yoga that can help relax and prepare your body for sounder sleep.
-Steer clear of foods that might trigger indigestion right before bed. Generally, try not to eat within three hours before bedtime. If you do have a late dinner, make it a lighter meal.
-Be sure to get ample sunlight during the day to keep your internal clock in-check.
-Try to keep a regular sleep routine — this helps the body know it’s time to sleep. That means get up and set a bedtime at roughly the same times each day. Your smartphone probably has a feature to help you stick to this schedule too.
Something else you may tend to overlook is your sleep environment and need to make it a pleasant one. Keeping your thermostat at a temperature that’s cooler is typically more conducive to better sleep; unless you get cold very easily, the optimal recommended sleeping temperature is between 60 and 67 degrees F. If you are easily awakened by external factors, consider investing in blackout curtains and wear earplugs or a sleep mask. Try turning off lights an hour before bedtime as well or if reading a book or magazine (the traditional versions) makes you drowsy, consider swapping your harsh lightbulbs for something softer or even red or orange-hued options.
And definitely avoid late night exposure to blue light; that means turn off your devices and your television at least an hour before bedtime; many studies suggest that blue light in the evening disrupts your brain’s natural sleep-wake cycles, which are crucial for optimal health. Blue light in the evening can trick your brain into thinking that light is actually daylight – this can inhibit the production of melatonin and reduce both the quantity and quality of your sleep.
Innovative sleep remedies.
Your smartphone could be your key to sleeping better, providing you don’t watch videos or check emails, etc. and expose your eyes and your brain to blue light. Take a look at your phone’s built-in features that can provide a bedtime reminder, monitor sleeping habits through sound or movement and may even be able to wake you during lighter stages of sleep to reduce sleep inertia, which is the grogginess we experience immediately upon waking.
You may have discovered some of the many apps and tech innovations available to help you get to sleep or that can identify and monitor episodes of sleep apnea. Here are a few ideas (product links are noted at the end of this article) to investigate to see if one of these can help you with your “good sleep goals”:
• Calm features meditations and stories with no tracking or monitoring.
• Fit Bit is a wearable device that monitors sleep AND tracks heart rate.
• The Garmin Vivosmart 4 can be used to monitor your overall health and can count calories, steps, and floors, and measures blood oxygen levels during workouts or sleep.
• Digital Finger Pulse Oximeter allows you to see what your blood oxygen levels are at any time.
• O2Ring™ Oxygen Monitor is FDA-registered and tracks your blood oxygen level, heart rate and body movements every second automatically and accurately.
• ResApp Sleep Check, requires no accessories or hardware other than your smartphone, is an obstructive sleep apnea screening test that uses overnight breathing and snoring sounds recorded on a smartphone placed on the bedside table. Results from a prospective, double-blind clinical study achieved 84% sensitivity and 83% specificity for identifying mild, moderate or severe OSA (AHI ≥ 5/h) compared to simultaneous in-laboratory PSG on a cohort of 582 patients.
• The Beddit, an Apple product, can measure all aspects of sleep, breathing, heart rate, and more through tiny sensors you place in your bed.
• Cardiogram is a free app for Android and iPhones that enables users to track their heart rate fluctuations using consumer wearables like an Apple Watch and Garmin. Cardiogram’s deep neural network technology, DeepHeart, can also detect hypertension and sleep apnea.
• Oura ring is similar to the Beddit, but designed as a comfortable headset “ring”.
• Dreem 2 delivers brief, precisely-timed sounds in phase with brain waves during deepest stage of sleep. The idea is to train brain rhythms to respond to the sounds and boost their activity, a method that has been associated with improved memory consolidation. In addition, the bone conduction technology allows the headset to transfer sound programs during the night (from falling asleep to waking up via deep sleep).
• Aurora by iWinks, in addition to a smart alarm and ability to track sleep, features the Aurora headband that uses EEG and eye movements to determine when the user is in REM sleep and emits light and sound stimulation to promote lucid, mindful dreaming.
• UrgoNight is meant to be worn during the day when you have down time and uses a form of neurofeedback with EEG monitoring to help improve nighttime sleep patterns.
• SleepSAT may offer a more tolerable CPAP alternative with a unique mouth guard design that features ports for oxygen delivered by an oxygen concentrator.
Ongoing sleep deprivation is nothing to ignore so please don’t wait to talk to a physician for guidance specific to your health. And check out some of the products we’ve noted here and let us know if you have any favorites that have helped you sleep easier. Remember, your brain is counting on it!
Lights out and sweet dreams to all,
Dr. Suzanne Gazda
Digital finger pulse oximeter