There are some activities that are for pleasure. Hanging out, watching movies, and reading are some of these. Then there are activities that are required for life. This list includes eating, drinking, and sleep. Sleep? Yes, sleep has a lot to do with how a body functions. Of the five human sleep stages, the rapid eye movement (REM) stage is the most researched, however much about this stage is still unknown. With numerous studies, it's a wonder we still are unclear about the exact workings of REM. Nevertheless the brain is a complicated structure and provides a challenge for scientists.

Some necessities for life are obvious; food, water, shelter, and love. When you break those down to processes necessary to your body you find sleep. Sleep is a vital part of life, deprivation of it can cause diseases and ultimately death (“Brain...”). Sleep is categorized into fives stages (1, 2, 3, 4, and REM, respectively). The 5th stage, REM, stands for rapid eye movement (“Brain...”). REM sleep stemmed from an extensive period of research in 1953 by a student named Eugene Aserinsky and his mentor, less involved, Kleitman (Siegel 92). Aserinsky made the discovery of a period of brain activation during sleep that recurred after periods of time (Aserinsky 222). In an early experiment, Aserinsky and a fellow researcher “found that motor characteristics of so-called 'REMs' were indistinguishable from those of waking saccades,” leading people to believe that not all sleep stages are the same (Aserinsky 215). This was a foresight to what Aserinsky would find to be his life's work. Through years of research things are a little clearer about rapid eye movement sleep. It has been found that about 20% of sleep is REM and common drugs like antidepressants as well as alcohol (which lightens your sleep) can suppress REM (“Brain...”). REM research has been improved on since Aserinsky's early time and while his method was more of a guess, researchers now are coming to find what really makes the brain tic.

REM sleep can be observed in two ways. One is through electronic equipment and the other through direct observation. REM sleep causes visible symptoms in people – if you know what to look for. Symptoms of REM sleep are caused by assorted parts of the brain (Siegel 98). During this sleep the body's temperature adapts to the environment, lowering or raising (Siegel 92), breathing will become rapids, irregular, and shallow in most cases, the eyes will jerk, the brain will dream (“Brain...”), and atonia will occur. Atonia is a state of muscle weakness which results in temporary paralysis. If the body did not go through atonia during REM, it would involuntarily act out the violent parts of a dream (Siegel 98). For people without atonia, they may develop RBD. RBD is the acronym for REM behavior disorder and is when people act out their dreams (“REM...”). This is a violent disorder that may cause a person to strike another or hurt themselves. Parkinson's Disease (a degenerative brain disease) is shown to develop in 40% of people with RBD and this will eventually cause their death (“REM...”). Another REM disorder is Nightmare Disorder. Nightmare Disorder causes stress in a person's life among other problems. When a person dreams two hours or more a night, this can become a hindrance to daily life (“Nightmares”). While disorders may happen, they are rare and it is doubted that the normal symptoms of REM will bother another sleeping person.

Maybe the most complex part of REM sleep is the workings of it. REM sleep takes a complicated course through many parts of the brain. Its path moves from the brain stem, to the pons (which controls atonia), then to the thalamus (the 'relay' station of the brain that organizes all sensations), on to the cerebral cortex, and possibly its ultimate stop is the brain areas for learning (“Brain...”). While it moves through these areas, different parts of the brain engage the workings of REM. In an experiment a scientist separated the top of an animal's brain from the bottom at the midbrain level. Why is this relevant? The scientist found that REM did not occur in the forebrain (top level of the brain) but the midbrain and brain stem showed signs. Studies like this have also shown that when some parts of the brain are damaged, dreaming does not happen. One of the most crucial parts to REM is the use of the pons. Full REM sleep is not possible if the pons isn't connected (Siegel 92, 96, 98) and one of the jobs of this brain part is to create atonia (“Nightmares”). Chemicals are also responsible for the REM state. Some chemicals have been found to also affect this. Gamma-aminobutyric acid (GABA) is a chemical that in some regions of the brain help REM while in others it causes wakefulness (Siegel 98).

Taking a closer look at the brain involves three main ways of identification. They include: inactivation, destroying brain part to see what it causes, activation, stimulating neurons, and recording, watching closely the brains neurons and neurotransmitters. Of course not any of these are perfect alone and should be used together. Machines are also used, the most common maybe being the Electroencephalogram (EEG) which measures brain voltage. By using this, scientists can compare the brain activity of an asleep or awake person. Coincidentally, the EEG reading of a person in a REM state is a lot like a person awakening (Siegel 92).

While much is known about REM sleep, a lot remains to be discovered. What exactly starts REM? What is the significance of sleep? Why is REM essential to life? Scientists are still trying to figure out what causes rapid eye movement sleep. Not only the brain structures that determine it but what chemicals are used. Human beings have been figured almost to the last atom. Not many mysteries still lie in accordance to nature but sleep is holding its ground. Aserinsky's research paved the way for a deeper look into body process. REM sleep is a good place to start for a better understanding of the human brain.

Works Cited
Aserinsky, E. “Memories of famous neuropsychologists: The discovery of REM
sleep.” Journal of the History of the Neurosciences. 5.3 (1996): 213-227.
“Brain Basics: Understanding Sleep.” National Institute of Neurological Disorders and Stroke. 21 May 2007. National Institutes of Health. 4 October 2013.
“Nightmares.” Psychology Today. 13 May 2010. Sussex Publishers, LLC. 4 October 2013.
“REM Behavior Disorder and Sleep.” National Sleep Foundation. 2013. National Sleep Foundation. 4 October 2013.
Siegel, J. M. Principles and Practice of Sleep Medicine: REM Sleep. St. Louis: Elsevier Saunders, 2011.