Unsynchronized Brain Waves During Sleep Make Us Forget

Likened to a tennis serve where the ball toss and the racket swing must coordinate
perfectly to score an ace, overnight brain waves must sync properly for remembering
to occur, a new study finds.  As with everything, it’s all about timing.  While slow
and fast brain waves are integrated and balanced in younger adults, when we age
slow waves that occur during non-rapid eye movement (NREM) sleep fail to fully
coordinate with quick electrical bursts known as spindles.

Using tennis terminology, the slow waves are like the toss of the ball, while the fast

waves are like the swing of the racket. If either of these two components are off in
terms of rhythm, the serve will either travel short or long in terms of distance, or go
out of bounds or the racket might even fail to make contact with the ball completely.
In sleep, this mistiming prevents older adults from being able to save new memories.  
These findings explain way older adults often seem able to better remember things
that occurred in the past rather than those that recently occurred.  The study also
suggests that this problem is the result of atrophy of the medial frontal cortex, an
area in the brain responsible for deep sleep which is restorative.  

The good news from this study is that there is now hope for a potential treatment
that could help with memory loss in aging adults.  New studies are being undertaken
to examine the effects of applying electrical stimulation to the frontal lobe of the
brain in an effort to synchronize slow waves with spindles   According to the studies
senior author Matthew Walker, “By electrically boosting these nighttime brainwaves,
we hope to restore some degree of healthy deep sleep in the elderly and those with
dementia, and in doing so, salvage aspects of their learning and memory,"

Source

Helfrich, R. F., Mander, B. A., Jagust, W. J., Knight, R. T. & Walker, M. P. (2017). Old Brains Come Uncoupled in Sleep:  Slow Wave - Spindle Synchrony, Brain Atrophy and Forgetting.. Neuron.  

Does the Color of Your Nightlight Affect Your Sleep?

Bright, white light can improve your mood, give you energy, make you feel more alert and less tired. This is great during the daytime but after sundown exposure to these type of lights that are similar to natural light can keep you from sleeping.  One of the ways artificial light does this is by suppressing melatonin, your body’s sleep hormone.  Since most people don’t go to sleep as soon as the sun sets, it’s important to use proper lighting to decrease your body’s natural response to daylight. The color of light you are exposed to at night can also affect your mood. Combined with the effects of good or poor sleep, the effect of light on mood can be significant.

Bulbs that emit light from longer wavelengths such as the red and orange spectrum are more likely to induce sleep. Incandescent bulbs, the type people use most frequently in their homes. These soft white bulbs are usually inexpensive and provide a warm light.  After red light bulbs, these are the best to use in your bedroom to induce natural sleep. Red bulbs are considered the best for sleep.  Use red or pink bulbs in your bedroom in nightlights or reading lamps used at night or right before bedtime.  Green light, another long wave light, can also induce sleep. Make sure to switch sleep inducing bulbs with those that are associated with wakefulness right before going to sleep, or use them in lamps not used during the day. If they are used when getting up in the morning, it will take longer to feel awake and alert and will increase the likelihood you will hit the snooze button.

Halogen bulbs give off the whitest light and are closest to daylight.  They should be avoided after dark.

Compact fluorescent bulbs are popular because they last about ten times larger than regular bulbs but give
off blue light which can interfere with sleep.   Light-emitting diode bulbs use about 75 percent less energy
than traditional bulbs but they also emit more blue light than traditional bulbs.  If you use these bulbs, it's
best to turn them off at least two hours before sleep. While this may seem inconvenient there are now a
selection of smart lights that you can set to automatically shift from brighter blue light to a warmer color a
few hours before bed.

Light from a laptop or tablet is also white or bluish white white so using these devices close to bedtime or
when you wake up during the night can also inhibit sleep. Cell phones can also be a problem as, although
their light is dimmer, you use them closer to your eyes than larger screens. While computers and cell
phone activity also inhibit sleep by causing the brain to remain active, you can decrease the overall effect
on sleep in where and how you use them. Don't play highly arousing games or engage in other activities
that are challenging and require a lot of thought or that make you feel agitated or excited. If you must play
games at all, try something that you find soothing, that doesn't take a lot of concentration, attention or
effort. Switch your computer or mobile device to nighttime display, which most laptops and mobile
devices now come with, and which emit less intense light and light from longer frequencies. Also make
sure you do not use these devices in bed and ideally not in your bedroom so this area of your home will
become associated in your brain only with sleep.