All posts by xinyin01pd2012

Excuses for not getting out of bed – Laziness, Ghosts, or neither?

This morning, I had a nightmare of a crazy lady latching onto me, and immediately, I felt like I couldn’t move and my body experienced intense vibration. I felt immense dread, and in the midst of panicking, I woke up. I could still feel the vibration and I still couldn’t move; like someone was pushing me down. It all felt very familiar –I realized that I was once again in the starting stages of my Sleep Paralysis.

That was a direct quote from my best friend Lina, regarding her experiences with Sleep Paralysis. After hearing of her creepy experiences for the first few times, I started to look up on the topic, as I have heard of many similar stories. Sleep Paralysis, is defined as defined as “a period of inability to perform voluntary movements either at sleep onset (called hypnogogic or predormital form), or upon awakening (called hypnopompic or postdormtal form)” ( It is believed to be a hereditary disorder, with symptoms being the inability to move limps at sleep onset or upon awakening, often accompanied by hallucinations of a malevolent existence in the room, commonly sitting on the victim, “paralyzing” him/her. Since this occurrence has been experienced by people across all cultures (in Chinese culture, this is referred to as Gui Ya Chuang, which literally translates to ‘Ghost pressing on you on bed’) for thousands of generations, there are many historical and urban myths that attempt to explain this, including ghosts and spirits ‘sitting’ on you to feed on your energy. However, I was curious as to how science would explain this mysterious phenomenon.

This well known painting (John Henry Fuseli (1781) - The Nightmare) depicts Sleep Paralysis as a visit from the demon.
This well known painting (John Henry Fuseli (1781) - The Nightmare) depicts Sleep Paralysis as a visit from the demon.

I knew that when one falls asleep, the body slowly relaxes, and one usually becomes less aware about. The body alternates between REM (rapid eye movement) and NREM (non-rapid eye movement) sleep – when the body is in NREM mode, it is still capable of tossing and slight movements. However, I found out that during REM mode, dreams occur and muscles are “turned off”. As a result, if you become aware before the REM cycle finishes, you will be left to notice that you are not able to move or speak. Why are our muscles “turned off”? This was to prevent a person from “acting out” a dream, so signals are sent from the brain to inhibit any muscle contractions.

Getting further into what the body does during REM mode – activation/inhibition activity is passed on from hormones and nerves to second messengers, which passes this on to third messengers and so on until the last messenger inhibits the motorneurons. So, if the nervous or endocrine system, for some reason, continues releasing neural inhibitors, a person may experience Sleep Paralysis while being awake during the REM period itself.

In essence, modern neuroscience describes the Sleep Paralysis as errors of the neural transmission of the brain during REM sleep. How are the hallucinations explained then? Extreme anxiety seems to be the reason. When the patient of Sleep Paralysis feels extreme panic, the brain releases signals that stimulate visual and auditory senses, producing hallucinations. Another explanation is that the patient is still dreaming, after some parts of the brain become awake, causing him/her to “see” images and “hear” sounds. Usually sleep deprived people are victims of Sleep Paralysis; reduction of anxiety, regular exercise, and a regular sleeping schedule are ways to prevent or stop Sleep Paralysis!

Since I have not personally experienced Sleep Paralysis, I personally find it difficult to believe the superstitious myths of ghosts and aliens that explain them, so I focused on the scientific explanation.

It is important to understand this, because armed with a scientific explanation, we need not be afraid of the popular myth that we have just been visited by a demon, or captured by aliens. This is an example of science being able to offer powerful explanations, reducing the dependency on superstitious explanations for seemingly mysterious occurrences. Another implication is how such occurrences show that we cannot fully trust our brains, as they are capable of “distorting, filtering, and interpreting sensory input, of altering memories and even generating false memories, and of generating false experiences” (NeuroLogica). It is necessary to understand that our brains contain flaws, and so relying solely on our memories or senses to understand the world would not be enough. Science provides the external verification to make up for our limitations.

Works Cited:

Sleep Paralysis.Stanford University. Stanford University, 26 Jan. 1999. Web. 21 Nov. 2011.

Sleep Paralysis: Page 2.Innovative Arts | Faculty of Arts. Web. 21 Nov. 2011.

Takahashi, Hiro. “Sleep Paralysis – Awake but Still Asleep.Serendip’s Exchange. Serendip, 01 July 2008. Web. 22 Nov. 2011.

Science: a matter of life (and death!)

Regardless of whether there is an after life or not, the fact that our physical bodies decompose remains. With the coming of Halloween, my research on spooky facts led my trail of thoughts to the morbid topic of decomposition after death. This got me started on thinking about my prior knowledge on the topic – our heart and brain shuts down, the body turns cold and stiff (according to the movies) and the body starts to decompose, the soil and maggots lending a helping hand in process. Finally, the body would completely disintegrate, ceasing to exist. Or at least that’s what I thought.

Decomposing Pig
Decomposing Pig

I became curious on whether or not what I knew was true. What really breaks our body down? It turns out that our own bodily processes help. Even when we’re well and alive, our body contains many decomposing enzymes and microorganisms. Bacteria in the large intestines helps to digest food when we are alive, but they also help break down dead cells in your body. Upon death, these enzymes start to break down the body itself, a process called autolysis, or self- digestion. Ever thought of why bodies stink? Well, this process is also the main contributor to the smells of a decaying body; when the body is being broken down, chemical reactions occur, producing gases. Hydrogen sulfide and methane are the two primary gases involved, and both carry a pungent odor. As these gases build up in the body they increase the body’s pressure from within, causing liquids to starts to seep from its openings! In addition, exothermic reactions occur; so really, in the initial stages, the body starts to heat up before turning stone cold!

Over the recent school break, I got to watch the movie “Dead Snow“, a movie that plays with the idea of Nazi zombies. As the media has always portrayed zombies with inflexible, rigid movements, it was much to my surprise that the body doesn’t actually stay rigid- it is only temporary. At the initial stages of decomposition, rigor mortis begins. A little bit of explanation here is required – muscle fibers have connections between them that cause contractions and relaxations of the muscle, this dependent on the presence of calcium ions. “The concentration of calcium ions is higher in the fluid surrounding muscle cells that inside the cells, so calcium tends to diffuse into the cell” (Australian Museum). Therefore, if the calcium level is higher within the cell, the muscle remains contracted. It is only through expelling of the calcium ions from the cell can the muscle be relaxed; however, this requires energy, energy that cannot be produced upon death.

Relax, rigor mortis goes away. Although cells in the body don’t ‘die’ immediately, instead taking anywhere from a few minutes to hours before they stop working, muscle cells would be lacking of oxygen, becoming unable to producing energy. Thus, the muscles are forced to remain contracted, until approximately 72 hours after death, when the muscle proteins would be broken down, causing the rigid cell connections to break down altogether.

Although I have only listed the first of many chemical processes that our corpses goes through, I hope that this post has satisfied your burning curiosity of some questions regarding this topic. Do keep in mind that everything mentioned above didn’t weigh in factors such as environment, temperature and climate – even the food in the stomach would affect the rate of decomposition! Nevertheless, this is enough ‘dead’ talk for me for the day. Why focus on the science of life, when, even in death, chemistry is with us?

Works Cited:

Decomposition – Body Changes – Australian Museum.” Australian Museum – Nature, Culture, Discover – Australian Museum. Australian Museum. Web. 24 Oct. 2010.

Decomposition.” Wikipedia, the Free Encyclopedia. Wikimedia Foundation, Inc., 21 Oct. 2010. Web. 24 Oct. 2010. .

Decomposition.” World of Forensic Science. Ed. K. Lee Lerner and Brenda Wilmoth Lerner. Gale Cengage, 2006. 2006. 24 Oct, 2010 .