Why do people shake in there sleep?
923809
Does it happen when you start to fall asleep?\n\nPeriodic Limb Movement Disorder (PLMD), also called nocturnal myoclonus, is a sleep disorder where the patient moves involuntarily during sleep. It can range from a small amount in the ankles and toes to wild flailing of all four limbs. These movements, which are more common in the legs than arms, occur for between 0.5 and 10 seconds, recurring at intervals of 5 to 90 seconds. A formal diagnosis of PLMD requires three periods during the night, lasting from a few minutes to an hour or more, each containing at least 30 movements followed by partial arousal or awakening.\n\nPLMD is a cause of insomnia and daytime sleepiness. The incidence of this disorder increases with age. It is estimated to occur in 5% of people age 30 to 50 and in 44% of people over the age of 65. As many as 12.2% of patients suffering from insomnia and 3.5% of patients suffering from excessive daytime sleepiness may experience PLMD.\n\nIt is related to restless leg syndrome (RLS) in that 80% of people with RLS also have PLMD. However, most people with PLMD do not experience RLS.\n\nThis disorder has made its way into popular culture, being referred to as "jimmy legs" and "jimmy arms" in an episode of Seinfeld, and has been known to cause couples to sleep in separate beds. In both examples, one subject suffers from PLMD severely enough to disturb the sleep of the other subject.\n\nPLMD is treated by medications aimed at reducing or eliminating the leg jerks or the arousals. Dopaminergic agents such as carbidopa/levodopa, pergolide, and a newer drug, pramipexol, are the treatment of choice for PLMD, as they decrease or eliminate both the leg jerks and the arousals. These medications are also successful for the treatment of RLS restless leg syndrome. In one study, carbidopa/ levodopa was superior to propoxyphene in decreasing the number of leg kicks and the number of arousals per hour of sleep. However, carbidopa/levodopa and, to a lesser extent, pergolide may shift the leg movements from the nighttime to the daytime.
117503
A very clumsy person.  See, the narcolepcy would cause them to collapse or their head to drop to their desk in an effort to get them to fall asleep.  Only since they are an insomniac they'd never really succeed at the actual falling asleep part.  So they'd end up just collapsing and hitting their head a lot without every really having fallen asleep.  They'd be the most "clumsy" person you know constantly falling for no reason.
252127
Because most of us get too little sleep - maybe it's a subconscious reaction.
1050640
I know many people who shake their leg while they sit. Just as a way to get rid of nervous energy. The only harm I've seen from it is that it annoys those sharing your bench (or couch).\n\nHappy Answering,\n~Tia~\nLive from the big, purple brain\nhttp://advision.webevents.yahoo.com/asktheplanet/brain.html\nASK YOUR QUESTIONS, CALL THE BRAIN - 212-382-3592
182892
Because it's diluted by drinking. You don't drink while you're asleep.
917605
I've been to lots of accident scenes and dealt with victims of violence and the answer is yes, people fill their pants all the time.  It's due to the fight or flight mechanism built into our bodies.  The body pumps blood to our vital organs (this is why our hands shake when we're scared)  The body also prepares to either fight or run so it gets rid of anything that isn't immediately associated with survival....so we puke and / or pee n poop our pants.
557557
Yeah, it's a side effect of the adrenaline and collagen that your body releases during stressful times.  Mother Nature didn't intend for us to be put in the kind of stressful social situations that we find ourselves in sometimes, but our body doesn't know the difference.  \n\nWhen you get stressed out, your body illicits the same response that it would if you were being attacked by a grizzly bear.  Your body uses adrenaline and collagen to prepare your body for the "fight or flight" response.  Basically, it is a way for your body to maximize the use of your muscles in the shortest possible time period.  \n\nWhen you don't use that energy, your body might start to use it automatically, resulting in uncontrolled shaking.
442542
It happens to the best of us. I think it is because they are so inactive during sleep, they need time to "wake up" just like we do!
612109
hormone isn't secreted when you shake your head. hormones are a chemically controlled substance that don't come out on a whim. \n\ni have a feeling that neurotransmitters are the culprits. neurotransmitters are sent throughout the body, Endorphins, which make you happy, might be the cause of this. \n\nheightened blood pressure, and lack of oxygen might increase the intensity of the neuotransmitter, which would lead to intense pleasure! the rapid movements of the nerve impulse to the synpases of the nervous system are the real technical cause..\n\nmaybe you're just shaking your head too hard.. and you're feeling light-headed. with all of the blood down there, i wouldn't be surprised that the dizzy feeling is from lack of blood! \n\nenjoy!
1106128
well, because when we sleep we have no control of our thoughts.\nIt's just  jumbled up pieces of our memory made into an interesting story.
1146388
Could be caused by water retention. Don't drink too much water right before you go to sleep. Stack up up ur pillows so your head is placed higher than your feet.
601178
As a general rule, it is usually one or the other that appears to fall asleep.  When a person is a diabetic, especially for a long time, they can develope such a thing called diabetic neuropathy.  This is when a limb, usually a leg or foot or both on one side becomes numb.  As a diabetic myself, this happened to me back in 1996.  It is scary sometimes and makes you really pay attention to your eating habits and making you take care of yourself better by regularly checking your blood sugar by using a meter.  Proper exercise and eating right will not correct neuropathy but it may prevent it from happening to other limbs in your body.\n\nAs for the shakes, it is common for that to happen.  That's why it is important for you or anyone with diabetes to eat regurlarly and don't skip on meals.  I hope this was helpful for you, good luck!
433679
When you fall asleep, you fall over.
760832
This strange falling sensation and muscle twitch is known as a hypnagogic myoclonic twitch or “Hypnic jerk” If this has happened to you on more than one occasion, don’t worry, you are not alone. Close to 70 percent of all people experience this phenomenon just after nodding off, according to a recent study at the Mayo Clinic. \n\nMost experts agree that this is a natural part of the sleeping process, much like slower breathing and a reduced heartbeat. The occurance is well known and has been well documented. However, experts are still not completely sure why the body does this. \n\n\nThe general consensus among researchers is that, as your muscles begin to slack and go into a restful state just as you are falling asleep; your brain senses these relaxation signals and misinterprets them, thinking you are falling down. The brain then sends signals to the muscles in your arms and legs in an attempt to jerk you back upright. This misinterpretation that takes place in your brain may also be responsible for the “falling” dreams that accompany the falling sensation. These “dreams” are not really normal dreams, as they are not produced from R.E.M sleep, but rather more like a daydream or hallucination in response to the body’s sensations. \n\nWhile this phenomenon happens to most everyone, studies have recently begun to link occurrences of “Hypnic jerks” to sleep anxiety, fatigue, and discomfort. People who are having trouble sleeping or can’t get comfortable in bed appear to experience the sensation more often throughout the night. It is especially more common with people who are trying to fight falling asleep or have deprived themselves of sleep for more than 24 hours. \n\nResearchers believe that the lack of sleep from sleep anxiety or sleep deprivation confuses the muscles and the brain. The muscles continually attempt to relax and shut down for rest, while your brain remains awake creating continued “misinterpretations” of falling or loss of balance. \n\nScientists and researchers continue to study sleep twitching and jerking in a small capacity, but state that the sensation is completely normal for our bodies and is “of little medical significance”. Our bodies go through several procedures of shutting down and preparing for an extended period of rest. “Hypnic jerking” is just one of them. It doesn’t appear to cause damage to body and poses no danger to our physical wellbeing.\n\nRandom info on Sleep Stages:\nAlthough sleep may seem like a steady state, it actually consists of several stages that cycle throughout the night. The types of brain waves present at the time (based on amplitudes and frequencies) determine the stage of sleep. Only a brief introduction to the stages of sleep will be presented here because a thorough examination of them is beyond the scope of this site. Most importantly, lucid dreams occur in the 5th stage of sleep, known as the REM (Rapid Eye Moment) stage (note: REM is read as a word, not as each individual letter). As the name alludes to, the most profound discernible characteristic of REM sleep is the bursts of rapid eye movement while dreaming. Although dreaming occurs during the other stages of sleep, the most vivid dreaming occurs during the REM stage.\n\nOne complete sleep cycle lasts about 90 to 100 minutes; therefore during an average sleep period a person will experience 4 to 5 complete sleep cycles. The sleep cycle begins with four stages of SWS (Slow-Wave Sleep), also called NREM (Non-REM). Note that after the completion of the 4th stage, the 5th stage does not immediately begin; instead, the first 4 stages quickly reverse and are then immediately followed by a REM period. The first REM period will occur roughly 90 minutes after falling asleep; thus the first REM period will last only about 10 minutes, given the length of each sleep cycle being roughly 100 minutes. The length of the stages is not static, however: as the night proceeds, the length of stages 3
974221
Because the bacteria in your mouth multiply overnight while your mouth is relatively dry and there is nothing coming through to stimulate the saliva to wash it away. n People who sleep with their mouths open have the worst time with sticky mouth and nasty breath.
1088124
sleep paralysis is a throwback from our hunter/gatherer days, caveman days, a long time ago. Back when we where not on top of the food chain and we were not the most powerful preditors. It is a defense mechanism that kept us safe at night. If we were asleep and moved, that would alert preditors out to get us. So our nervous system prevents the body from involuntarily moving while we are most vulnerable, while we are in a deep sleep. It is not supposed to continue when we are conscious but it does happen. If it happens while we are having a bad dream it seems logical to associate the feelings of terror and fear with evil but it is in our minds.
1174829
because our bodies are low on oxygen... we yawn to take in a big gulpl of fresh oxygen to awaken our sleepy oxygen deprived brain... you know it does a body good.