When you wake up, you can’t feel your arm. What’s really happening when you wake up with a dead arm? Waking up with a dead dream is a pretty scary experience. In your tired state, you might begin to panic. Generally, don’t feel panic. A few minutes later, the feeling always comes back following a bit of pins and needles.
Recently, a famous neurology researcher comes out with an explanation: revolving around how the body protects itself during sleep. You might mistake the idea that you sleep is restricting blood flow to the arm. Conversely, these symptoms are likely caused by nerve compression – nerves are being pushed on and squashed.
Four different types of nerve in the arm
- Ulnar nerve – spreads the fingers
- Axillary nerve – Lifts the arm at the shoulder
- Musculocutaneous nerve – bends the elbow
- Radial nerve – straightens the arm and lifts the wrist and fingers
And, any of these nerves can be compressed either under your own body or that of your partner. Thus, the flow of information between the limb and your brain will be disrupted.
Two main theories on why nerve compression causes numbness
- A sign of sleep paralysis
The brain sends a signal during REM sleep to essentially paralyze the whole body, stopping you from acting out your dreams. However, sometimes, before your limbs do, you will wake up.
Compressing the nerves damages them. Then, your body wakes you up as a natural protection measure. “The nerves are firing spontaneously. Thus, the nerve structures, as they recover, tend to be irritable for a period of time. But, most of the time, the feeling of pins and needles is a good sign. And, this temporary phase means nerves are coming back to life,” said by University of Rochester Medical Centre in New York.
Should we be worried?
When we sleep, we don’t need to worry about arm. In most cases, it won’t cause any lasting damage to the nerves. But in some cases where the issue may be a little more serious.
It might likely happen while you’re drunk. This is called “Saturday night palsy”. To be specific, this refers to the times when the brain is too impaired to wake up the body to protect the nerves from compression. Besides, you might wake with a very numb hand or arm which could take a few days to heal.
People who have hereditary neuropathy with liability to pressure palsies (HNPP) more susceptible to nerve compression injuries and get injured simply from crossing their leg in a certain way for too long.
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