I took a nap today. I fell asleep with my textbooks strewn about the couch and coffee table, and I think it's safe to say what followed was probably one of the worst experiences of my life.
I drifted off to sleep and was dreaming for probably close to fifteen minutes, when I lucidly decided it was time to wake up. I started opening my eyes until they were open... until I realized they weren't. So then, I tried to lift my hand up to help the awakening process, but this failed too. The next moment I realized I couldn't move a single muscle in my body. I kept trying and trying, nothing moved. Then panic set in. It felt like someone was smothering me, and had taken the breath out of my voice. It was terrifying. I tried to pull my muscles to move, but nothing worked. My heart was racing and I tried to yell out to my sister who was in the kitchen - I couldn't. I kept trying and trying to move muscles but felt completely paralyzed.
Following this, I witness some terrifying imagery around and on the coffee table. If I were to describe it, I'm sure someone would call me crazy, so I won't. All I'll say is that I was panicking, and it felt 100% real. At a certain point, I was finally able to move my foot, and mobility was at last returned to my whole body. The second I got up, I looked around the room to ensure the crazy and horrific hallucinations (or dreams) I witnessed were not real. I took a breath, and made sure I was awake.
So I went to a computer to research as a way of making sure I didn't have some rare mental disorder. But as I researched, I discovered that, apparently, it can be fairly common, and is in no way a mental disorder or a real problem. As it turns out, I experienced sleep paralysis in a hypnopompic phase of sleep. I read some testimonies of other people who experienced what I did and discovered that it is fairly easy to explain.
As I learned in psychology, we all go through REM (Rapid Eye Movement) sleep, which is the point during the night (or nap) that we dream and gain restfulness. When we have dreams, our brain secretes a chemical that hampers us as a way of preventing our acting out the physical movements in out dreams, our body is in a state known as "nonreciprocal flaccid paralysis." Some peripheral muscles, like those in the fingers and the eyes, maintain the ability to contract and move, which is probably why I was able to open my eyes slightly. Basically the body is attempting to wake up, but the brain is stopping it to do so because it has not completed a full REM cycle. Also, to explain my hallucinations, the neurotransmitters may stil transmit the thoughts and imagery of dreaming, while the rest of the body is attempting to wake up - what seemed like a terrifying experience in that room was actually an incorporation between my sense of reality, and my dreaming. Here's a quote I found that describes it in a far more technically accurate way.
"Also, hallucinations during Sleep Paralysis may happen, for one keeps dreaming even after some parts of his brain wakes up directly from REM sleep. Since the nervous and endocrine systems continue to release the neural inhibitors which sustain the paralysis, it may be possible that those systems keep releasing the neural activators that stimulate dreaming. Thus, a person continues to "see" the images and "hear" the noises produced in the dream that he has just had in REM sleep from which he has awaken. The hormone melatonin, a "master hormone" (5) that mainly controls circadian rhythms, also seems to play an important role in enhancing the REM state; the level of melatonin secretion by the pineal gland reaches its lowest during REM sleep (5). Such neurotransmitters and hormones probably activate or inhibit the activity of second messengers, which then activate or inhibit the third messengers, and so on till the last messenger inhibit the synaptic transmission or cause hyperpolarization of the motorneurons. And if, for some reason, the nervous or endocrine system continues to release the neural inhibitors, a person may experience Sleep Paralysis as he enters awakefully into or awakens directly from REM period (2)." (Hiro Takahashi, http://serendip.brynmawr.edu/exchange/node/1740)
It's safe to say I'm horrified at the idea of napping, now. But, there's a part of me that's happy there is a reasonable explanation for this. Don't call me a geek for looking this stuff up, because if you experienced what I did, you would definitely be terrified of taking naps.