Saturday, August 24, 2013

Stages of Sleep

The two main sleep cycles within which most mammals alternate are slow-wave sleep (SWS) and rapid eye movement sleep (REM). SWS is subdivided between four stages of sleep. Sleep stage 1 in which the heart rate slows and muscle tension decreases (Breedlove, Watson, & Rosenzweig, 2010). Stage 2 sleep is characterized by spindles (short bursts of brain energy) and cooling of the brain, and stage 3 sleep is characterized by the same spindles as in stage 2 sleep and delta waves characteristic of stage 4. Stage 4 is the deepest sleep stage and is characterized by delta waves at least 50% of the time. REM sleep is the stage in which people do most of their dreaming. Dreams in REM sleep are characteristically more vivid than the thinking dreams that take place in non-REM sleep.

Two Potential Effects of Sleep Deprivation
The effects of sleep deprivation have been referred to as bizarre behavior that has been likened to schizophrenia (Breedlove, Watson, & Rosenzweig, 2010). Chronic, and even short-term insomnia can alter an individual's ability to react appropriately (Colton & Altevogt, 2006). Ultimately, chronic long-term insomnia can damage the immune system and cause death, perhaps because of sleep destroying the body's ability to thwart inflammation and the disease process (Gruber, 2013). Gruber (2013) claimed sleep is necessary for normal emotional functioning.

Sleep deprivation compromises an individual's capacity to regulate emotions (Walker, & van der Helm, 2009). This process can cause a cycle of sleep deprivation, lack of emotional regulation, increased stress which increases the inability to sleep, all of which interferes in psychological well being (Gruber, 2013). Colton and Altevogt (2006) claimed sleep loss is a common, yet ordinarily overlooked health problem for 50-70 million Americans. All of these individuals suffer consequences of cognitive functioning, although these losses are not always easily identifiable (Colton & Altevogt, 2006). Gross errors in judgment is one of the most common effects of sleep deprivation. Further, hypertension and obesity develop after years of chronic lack of sleep (Colton & Altevogt, 2006)

The Mechanisms of Modern Sleeping Pills
Breedlove et al., (2010) explained that benzodiazepines (z-drugs) bind to GABA receptors and disengages the activity of some neurons. GABA is an inhibitory neurotransmitter and benzodiazepines bind to at least five of these receptors (Thornton, 2010). After binding to these receptor sites, the inactivity of neurons has an effect on surrounding neurons, which calms the nervous system, and this results in the ability to fall asleep (Jerome, 2013).

Thornton (2010) explained that within the midbrain, humans have specialized neurons that can "trigger reflex behaviors" (para. 26). Normally, these are disengaged by the more intelligent forebrain. When people sleep, their forebrain sleeps as well, and they lose the capacity for self-restraint. This is not usually a problem because they are asleep. However, for individuals predisposed to parasomnia, sleep drugs can provoke the individual to engage in wakeful unrestrained actions. The problem is that these individuals are asleep and have no conscious awareness of their actions (Thornton, 2010).

Advantage and Limitation of Sleeping Pill Use for Insomnia

The advantage of sleep drugs is that they save individuals from the throes and negative effects of insomnia. Several limitations exist for the use of these pills: their addictive properties are well-documented and recently it was found that they can increase the risk of Alzheimer's (Jerome, 2013). Further, sleeping pills can cause parasomnia, which can lead to odd, dangerous, and unconscious behaviors (Thornton, 2010).


Breedlove, S. M., Watson, N. V., & Rosenzweig, M. R. (2010). Biological psychology: An introduction to behavioral, cognitive, and clinical neuroscience. (6th ed.) Sunderland, MA: Sinauer Associates, Inc. Publishers.

Burne, J. (2013, January 8). Is there any such thing as a SAFE sleeping pill?. Daily Mail. p. 25.

Colten, H. R., & Altevogt, B. M. (2006). Sleep disorders and sleep deprivation [electronic resource] : an unmet public health problem / Committee on Sleep Medicine and Research, Board on Health Sciences Policy ; Harvey R. Colten and Bruce M. Altevogt, editors. Washington, DC : Institute of Medicine : National Academies Press, c2006.

Gruber, R. (2013). Making Room for Sleep: The Relevance of Sleep to Psychology and the Rationale for Development of Preventative Sleep Education Programs for Children and Adolescents in the Community. Canadian Psychology, 54(1), 62-71. doi:10.1037/a0030936

Jung, C., Melanson, E., Frydendall, E., Perreault, L., Eckel, R., & Wright, K. (2011). Energy expenditure during sleep, sleep deprivation and sleep following sleep deprivation in adult humans. The Journal Of Physiology, 589(Pt 1), 235-244. doi:10.1113/jphysiol.2010.197517

Kripke, D. F., Langer, R. D., & Kline, L. E. (2012) Hypnotics' association with mortality or cancer: a matched cohort study. British Medical Journal Open 2(1) doi:10.1136/bmjopen-2012-000850

Thornton, J. (2010). The weird & dangerous world of sleeping pills. Men's Health (10544836), 25(7), 146-153.

Walker, M. P., & van der Helm, E. (2009). Overnight therapy? The role of sleep in emotional brain processing. Psychological Bulletin, 135(5), 731–748.

No comments:

Post a Comment