Science, Art, Litt, Science based Art & Science Communication
Q:Sometimes I feel someone is giving me an immediate push while I was asleep, like a ghost kicking me with a sound which makes me wake up. What might be happening?
Krishna: After reading your question, I could think about a few things.
1. Sleep paralysis: Up to as many as four out of every 10 people may have sleep paralysis. This common condition is often first noticed in the teen years. But men and women of any age can have it.
During sleep, your body alternates between REM (rapid eye movement) and NREM (non-rapid eye movement) sleep. One cycle of REM and NREM sleep lasts about 90 minutes. NREM sleep occurs first and takes up to 75% of your overall sleep time. During NREM sleep, your body relaxes and restores itself. At the end of NREM, your sleep shifts to REM. Your eyes move quickly and dreams occur, but the rest of your body remains very relaxed. Your muscles are "turned off" during REM sleep. If you become aware before the REM cycle has finished, you may notice that you cannot move or speak.
If you find yourself unable to move or speak for a few seconds or minutes when falling asleep or waking up, then it is likely you have isolated recurrent sleep paralysis. During this time, you might 'feel' your dreams are true and if they are nightmarish, you think you are dealing with ghosts, which is not actually true.
Factors that may be linked to sleep paralysis include: Lack of sleep, sleep schedule that changes, mental conditions such as stress or bipolar disorder, sleeping on the back, other sleep problems such as narcolepsy or nighttime leg cramps, use of certain medications, such as those for ADHD, substance abuse.
Usually, you don’t need to go for a treatment. But treating any underlying conditions such as narcolepsy may help if you are anxious or unable to sleep well. Improve your sleeping habits. Try to reduce your stress levels.
2. Hypnic jerks: Hypnic jerks, which people also refer to as hypnagogic jerks or “sleep starts,” are involuntary muscle contractions that some people experience as they are falling asleep. It tends to happen just as the person is transitioning from a wakeful state to a sleeping state. Some hypnic jerks are mild and hardly noticeable. Others can be intense — anyone who has been close to falling asleep and then felt a sudden jerk that has woken them up has experienced a hypnic jerk. It is possible to wake up from a hypnic jerk, but this does not always happen, as the strength of the muscle contraction that a person experiences will vary. In some cases, these large contractions can make a person feel as though someone else is pushing them off the bed. The other symptoms of a hypnic jerk may also wake the person up. Sometimes the person dreams that they are falling either out of bed, from a tree, or through a void. Although it is uncertain which sensation comes first, this can be enough to scare the person awake.
Hypnic jerks are common and occur randomly. The exact cause of these twitches is unclear, but some factors may increase their likelihood.
Hypnic jerks are a type of involuntary muscle movement called myoclonus. Hiccups are another common form of myoclonus. The strength of a hypnic jerk may vary. Some people may not be aware of the twitches, and may only know that they experience them if somebody else notices the movements. Other times, the spasms can be strong enough to startle the person and wake them up.
People may experience other symptoms alongside hypnic jerks, such as: feeling as though they are falling, rapid heartbeat, rapid breathing, sweating, dreaming about falling. These sensations are not signs of any underlying health conditions.
However, there are some theories about why these sleep starts occur. Possible reasons may include:
Exercise: Exercising stimulates the body, so exercising late in the evening may make it more difficult for the body to relax in time for sleep. This excess stimulation may cause a hypnic jerk.
Stimulants: Body and brain stimulants, such as caffeine, nicotine, or some drugs, may make falling asleep or staying asleep throughout the night difficult. They may also increase the frequency of hypnic jerks.
Stress and anxiety: A high-stress lifestyle or feeling very anxious can make it difficult to relax in preparation for sleep. An alert brain may be easier to startle, so a person may be more likely to wake up when these involuntary muscle twitches occur.
Poor sleep habits: Irregular sleep patterns, sleep deprivation, or regular sleep disturbances may lead to hypnic jerks.
While it may not be possible to avoid all instances of hypnic jerks, some people may notice that they have them less frequently when they make a few lifestyle changes.
Tips that may help prevent hypnic jerks include:
Exercise is vital, but too much physical stimulation close to bedtime may increase the likelihood of these muscle twitches.
Exercising earlier in the day instead can give the body plenty of time to relax and unwind before bed.
Caffeine sources, such as coffee, tea, and chocolate, may help a person wake up in the morning, but having caffeine later in the day can stimulate the body and brain too much, making it difficult to transition to sleep.
Other stimulating drugs, such as nicotine and alcohol, may lead to restless sleep, which can result in issues with sleep deprivation or disruptive hypnic jerks.
Creating a bedtime routine may help the body relax and reduce stress. Some people drink calming teas or warm milk and read a book before bed. Others may prefer to do gentle stretches or listen to music.
Blue light, which is the cold light from some light bulbs, televisions, computer monitors, and smartphones, tells the body that it is daytime.
Turning down these lights or avoiding technology before bed will reduce the levels of blue light and may help a person relax.
Some people use breathing exercises to help them relax. Something as simple as taking slow, deep breaths for 5 minutes may help a person reduce their stress levels.
Anyone who is experiencing hypnic jerks regularly and is concerned about their overall health or sleep quality should talk to a doctor. In some cases, doctors can prescribe medications to help a person get more restful sleep and avoid hypnic jerks.