We may spend eight hours every night doing it, but it remains a shrouded mystery what we do when we are asleep.
Many of us may be even suffering from sleep conditions without knowing it.
Dr Lim Li Ling of Singapore Neurology & Sleep Centre, Gleneagles Medical Centre and President of the Singapore Sleep Society says that as we age, we become more prone to sleep disturbances.
This is because there is a natural decline in sleep quality with age, as well as medications interfering with our sleep patterns.
And there are many strange sleep phenomenon that can occur between the stages of wakefulness and sleep, Dr. Philip Gehrman, PhD, CBSM, clinical director of the Behavioral Sleep Medicine Program at the University of Pennsylvania told Huffington Post.
For example, while you are likely familiar with insomnia, grinding of teeth and snoring, did you know of conditions where muscles go haywire during sleep, night terrors and exploding head syndrome?
He added that these events are normal, and can be categorised as those that happen during non-REM sleep, and those that happen in REM sleep.
To encourage Singaporeans to look into their sleep needs for Singapore Sleep Awareness Week 2012, to be held from March 16 to 25, YourHealth looked into the nine strangest things that happen during our shut-eye, and the scientific reasons behind them:
1. Sleep paralysis
If you've ever experienced suddenly realising you are frozen when you've drifted off to sleep or just woken up, you may have encountered sleep paralysis.
Commonly occurring during the first few minutes of waking up, sleep paralysis is basically when your mind is awake but your body still thinks you are asleep.
When we fall asleep, our muscles get automatically paralysed so that we do not act out on our dreams. However, during sleep paralysis, a part of the brain wakes up earlier than the rest, giving the sense of being mentally alert, yet unable to get up.
This condition, while being scary, is not dangerous, and passes after time.
However, to decrease the incidences of this happening, it is best to reduce stress levels and get a good eight hours of sleep.
Do you grind your teeth?
2. Teeth grinding (bruxism)
Bruxism is when you clench (grip your top and bottom teeth together) or grind (slide your teeth back and forth over each other) your teeth.
People can clench and grind without being aware of it during the day and when asleep, and this can happen in both children and adults.
The cause of bruxism is not completely agreed upon. But doctors speculate that daily stress may be the trigger in some people.
The grinding forces can be quite strong and occur over a long period of time, especially during sleep. This can cause the outer layers of enamel to wear away gradually, exposing the dentin and dental nerves, resulting in tooth sensitivity.
I'm asleep. How do I know I grind my teeth?
You may be a bruxer if you experience any of the following:
>> Tightness/ pain of the jaw muscles
>> Painful/ sore jaw joint (temporomandibular joint dysfunction / TMD)
>> A grinding sound at night (the person grinding is asleep and unaware. This is usually heard by someone else)
>> A dull headache
>> Worn down/cracked teeth
>> Broken dental fillings/restorations and injured gums
>> Sensitive teeth
Clenching or grinding the teeth puts pressure on the muscles, tissues, and other structures around your jaw.
Bruxism can cause permanent damage to the dental structures, uncomfortable jaw pain, and headaches. Severe grinding can damage teeth and result in cracked teeth, dead teeth requiring root canal treatment or even tooth loss.
The best option would be to consult a dentist for a full evaluation. If the condition is severe, your dentist may refer you to specialists.
If stress is suspected to be the cause, stress management may also be recommended. To prevent damage to the teeth, mouth guards or dental splints have been used to treat bruxism.
A splint may help protect the teeth from the pressure of clenching and to relieve pain at the joints. The dentist may also advice some cold or hot compress, jaw exercises and also to avoid eating hard foods like nuts, steak, ice etc.
Orthodontic adjustment of the bite pattern may help some people, but surgery is usually considered as the last resort.
Exploding head syndrome
3. Exploding head syndrome
A relatively rare occurrence, this bizarre experience has been likened to a sensation of your head "exploding", because of a loud noise going off in the head.
Associated to waking with a loud "bang", this often leads the person to consult his or her doctor, convinced of a burst blood vessel in the brain, said Dr Lim.
This syndrome is not dangerous, however, and is thought to be related to hypnic jerks.
4. Jerking in your sleep
If your partner has complained before of getting hit by a wild hand during sleep, he or she is not alone.
You (being asleep) may not notice when you suddenly jerk your body or limbs, but it is quite common and relatively harmless (perhaps not for your partner).
It occurs when a person is falling asleep and may be accompanied by a feeling of falling into deep space or of losing balance.
Termed hypnic jerks, they do not warrant treatment unless they occur repetitively in a single night, delaying the onset of sleep. It usually disappears once you are truly asleep.
5. Violent sleeper (REM Sleep Behavior Disorder)
As mentioned, for most of us when we enter REM sleep, our bodies become paralysed as our muscles lose tone. This is a natural protective mechanism that prevents us from acting out our dreams.
>People who lose this paralysis during dream sleep are able to act out their dreams, and these are usually negative ones involving fight or flight.
Their behaviours and actions during sleep are usually consistent with dream content, and may consist of talking, yelling, screaming, punching, and even jumping around in bed.
People who experience this REM Behaviour Disorder are usually adults. This may indicate an underlying sleep-related breathing disorder or neurological condition (or may occasionally herald one).
Socially, this usually results in marital discord as physical injuries may be inflicted on self or bed-partners during the sufferer’s dream re-enactments.
Management includes safety measures for the bedroom, medications to reduce the occurrence of this behaviour and treatment of associated or underlying conditions.
6. Sleep walking/talking
This is when part of your brain is awake, but the rest of it is asleep.
Sleep-walkers tend to engage in routine basic behaviour, such as going to the toilet, walking to the kitchen to open the fridge for a bite, or taking a walk.
As it occurs during non-REM sleep, where mild dreaming happens, the actions are unlikely to be related to what they are dreaming about.
While it is not dangerous by itself, sleep walking can lead to dangerous activities that can be fatal (unlocking the door to go outside). You can take precautions by putting safety latches on doors, locking windows etc.
7. Restless Legs Syndrome
Have you ever experienced an abnormal sensation in the legs, and sometimes involving the hands, in the night before bedtime?
It might be a condition known as Restless Legs Syndrome. The sensations experienced may range from numbness, pins-and-needles, water running through the legs, crawling ants, and many more.
They uniformly make it difficult for the sufferer to fall asleep. This condition is known to be related to low iron levels in the blood and this should be screened for, besides excluding an underlying nerve/spinal cord disorder. Effective medications are available to treat this condition.
Getting out of bed and walking/pacing may bring some measure of temporary relief for the sufferer.
8. Bed wetting
Also called enuresis, it is when a child or person older than the age of five or six involuntarily urinates. It can occur in the day or night.
This condition is very common in children, when they are less capable of maintaining bladder control. Most children outgrow it as they get older without intervention from parents.
One reason is maturational delay, where a child has not physically matured to the stage where he or she can control the bladder throughout the night.
Another reason is that for some kids, the urge to urinate is not enough to rouse them from their sleep.
For prevention, there are technological solutions, such as bedwetting alarms which are set off by moisture, hence waking the child up to go to the bathroom.
9. Night terrors
Another condition common in children are night terrors.
Do you have children who occasionally wake up crying and screaming for no apparent reason, not even recognising their own parents?
They may have been suffering from night terrors, which are different from nightmares as a child experiencing night terrors is actually asleep.
They typically do not recall the episode the next day, even though they may last as long as 20 minutes or even longer.
While parents may feel helpless in such situations, the best option is not to wake the child up and let the terrors pass, as they are not harmful for children.
Sleep an hour more
While most of these conditions are relatively harmless, some can cause us to lose out on our beauty rest.
The lack of sleep affects cognition and performance, shackling our memory, concentration, alertness and mood.
Left untreated, long term sleep disturbances decrease quality of life, and can lead to increased morbidity and mortality, Dr Lim said.
March 16, today, is World Sleep Day. Celebrate by switching off your mobile phone, computers and TV, and tucking in early tonight.
You can also go to the "Sleep An Hour More" movement on Facebook to pledge your support against voluntary sleep deprivation.
The information in this article was contributed by Dr Lim Li Ling of Singapore Neurology & Sleep Centre, Gleneagles Medical Centre and President of the Singapore Sleep Society.
Events and Talks
Events and talks to learn more:
OPEN HOUSE @ KK Women's and Children's Hospital (KKH)
Date: 17 March 2012 (Sat)
Time: 10.00 am - 11.30 am
Venue: KK Women’s and Children’s Hospital, Women’s Tower Lecture Theatre
Registration: Please contact Miss Grace Teo Tel: 6394 8811 or email Grace.Teo.SY@kkh.com.sg with your name(s), contact number.
Attendance is free.
Registration Deadline: 12 Mar 2012 or until (40) seats are filled.
Topics covered: Sleep hygiene in children. Behavioural sleep problems in children. Parasomnias. Obstructive sleep apnoea. Excessive day time sleepiness. Morbidity related to sleep problems in children and their long term implications.
OPEN HOUSE @ National University Hospital (NUH)
Date: 23 March 2012 (Fri)
Time: 11.00 am - 2.00 pm
Venue: NUH Main Building Level 3, DLM (Department of Lab Medicine) Lecture Theatre. Please use Lift Lobby 1.
Registration: Please call Miss Siti Faezah at 6772 2244.
Attendance is free.
Registration Deadline: 16 March 2012 (Fri)
Topics covered: Talk on "Snoring and Obstructive Sleep Apnoea - What Do We Need to. Tour of NUH Sleep Lab cum "Live" Demo of Sleep Study.
OPEN HOUSE @ Singapore General Hospital (SGH)
Date: 24 March 2012 (Saturday)
Time: 10.00 am - 12.00 pm
Venue: Singapore General Hospital, Outram Road, Singapore 169608 Deck on 9, Block 6, Level 9 (Visitor Registration required at the Blk 7 Visitor Registration Services)
Registration: Please call Sleep Disorders Unit at 6326 6621 or email: firstname.lastname@example.org with your name(s), contact number
Registration Fee: $5 nett per participant (cash payment on the actual day)
Registration Deadline: 21 March 2012 (Wed)
Topics covered: Obstructive Sleep Apnoea: Not Just Snoring in Your Sleep. When Sleep Just Won't Come.
Open House Activities: Have a feel of Continuous Positive Airway Pressure therapy, learn how to relax mind for better sleep and see what a sleep study is about!
"Sleep For Success" Public Symposium & Fair
Date: 24 March 2012 (Sat)
Time: 1.30 - 5.00 pm
Venue: Sheraton Towers, Ballroom 2, Level 2, 39 Scotts Road, Singapore 228230
Registration Fee: $10 nett per person (includes light refreshments)
To register: Phone: 6854 6692 (Mon - Fri : 8.30am - 6.00pm) | Fax: 6854 6667 | Email: email@example.com
Topics covered: What are some of the sleep problems affecting good sleep? Get your nagging sleep questions answered by our panel of sleep specialists. A sleep fair will also feature our partners who may have the solution for your sleep problem.
Visit the Facebook page for the "Sleep An Hour More Movement" to pledge your support!