Abstract
Rechtschaffen (1983) and his students at the University of Chicago conducted a study on the effects of sleep loss on rats. Their experiments showed that well-controlled and sustained sleep deprivation were uniformly fatal to rodents. Human studies on the effects of sleep deprivation yielded results that are similar to those of Rechtschaffen’s.
The Study of Rechtschaffen (1983) on Sleep Deprivation
Adequate sleep is very important in maintaining good health. Sleep enhances various physiologic processes mainly through cell repair. The restorative functions of sleep include fatigue reduction, mood stabilization, immune system maintenance and the improving of blood flow to the brain. Sleep likewise increases the capacity for learning and memory storage (Timby, 2008, p. 391).
Sleep deprivation, therefore, has detrimental effects on a person’s health. Because sleep repairs damaged cells, the lack of it will make the body more prone to illnesses and decrease its overall performance. Weakness, irritability, disorientation and tremors are some examples of the short-term impacts of sleep deprivation. If not solved, sleep deprivation can also increase the body’s susceptibility to long-term, serious conditions such as hypertension, diabetes, depression, bipolar disorder and attention-deficit hyperactivity disorder (ADHD) (Andreassi, 2007, p. 115).
Sleep Effects on Immunity
Numerous animal studies have already established the close connection between sleep and the functioning of the immune system. All of these studies indicated that prolonged sleep deprivation can be fatal. Several long-term sleep deprivation studies on puppies and adult dogs in the late 19th and early 20th centuries all resulted in death over periods of 3 to 77 days. These canines were found to have various pathologies, including hypothermia, weight loss and reduction in red blood cell counts (Opp, Born, and Irwin, 2007, p. 596).
Allan Rechtschaffen (1983) and his students at the University of Chicago conducted a similar inquiry on rats (Opp, Born, and Irwin, 2007, p. 596). Their experiments showed that well-controlled and sustained sleep deprivation were uniformly fatal to rodents. Physical changes were noted in rats by the end of the second week of their study. The rats eventually died.
Details of Rechtschaffen’s Study
Rechtschaffen and his students carried out their research by coming up with the disk-over-water method of sleep deprivation. An experimental animal and a control animal are placed on a flat disk that is separated into halves. The rats on each half of the disk have equal access to food and water. A computed algorithm detects their entry into sleep (Opp, Born, and Irwin, 2007, p. 596).
When this computer algorithm discovers that the experimental animal is falling asleep, the disk is slowly rotated until it wakes up. If the rat remains asleep despite the rotation of the disk, the partition wall will force it into a shallow pan of water. The rat must then wake up and get back onto the disk, or remain in the water. Although the control animal may also be sleep-deprived, it is able to sleep when the experimental animal is in the water (Opp, Born, and Irwin, 2007, p. 596).
Outcomes
All of the experimental animals in Rechtschaffen’s study died – their survival times throughout the research ranged from 5 to 33 days. In sharp contrast, none of the control animals died. Many subsequent studies that used the disk-over-water method of sleep deprivation came up with more elaborate results by grouping experimental animals according to their survival times (Opp, Born, and Irwin, 2007, p. 597).
According to Rechtschaffen, et al. (1989), these researches “(came up with) survival times (which ranged) from 11 to 32 days when rats were deprived of all sleep, and from 16 to 54 days when selectively deprived of REM sleep” (Opp, Born, and Irwin, 2007, p. 597). In the process, they were able to determine the ailments that were associated with sleep deprivation. The rates of these disorders – scrawny and debilitated appearance, severe ulcerated skin lesions on the tail and plantar regions of paws, increased food intake – reached 80% above baseline levels for total sleep-deprived rats during the final quartile of their survival. For the REM sleep-deprived rats, meanwhile, the rates were 100% above baseline levels (Opp, Born, and Irwin, 2007, p. 597).
Despite huge food intake, the rate of weight loss among the total sleep-deprived rats was at about 18%. Among the REM sleep-deprived rats, the percentage was estimated to be at around 22%. During the mid-to-late stages of deprivation, both sets of rodents experienced increased energy expenditure and decreased body temperature. Their respective levels of norepinephrine and plasma thyroxine also increased and decreased, respectively (Opp, Born, and Irwin, 2007, p. 597).
Sleep Deprivation Syndrome
The aforementioned ailments, collectively known as sleep deprivation syndrome, indicated severe multiple organ failure on both the total sleep-deprived rats and the REM sleep-deprived rats. The proximal cause of their deaths, however, was still undetermined. Carole Everson (1993) was able to pinpoint the exact cause of the demise of these rodents by demonstrating that the rats that were subjected to sleep deprivation until death became septicemic. Sleep deprivation lowers the immune system, which, in turn, enables the infection of mesenteric lymph nodes by viable bacteria (Opp, Born, and Irwin, 2007, p. 597).
Everson claimed that long-term total sleep deprivation elevated the levels of serum IL-1β and endotoxin in rats. These increases in serum IL-1β and endotoxin are evident within just 10 days of sleep deprivation – the average time of death for total sleep-deprived rats was estimated at 21 days. Rodents that have high levels of serum IL-1β and endotoxin are more prone to septicemia than those who do not (Opp, Born, and Irwin, 2007, p. 597).
In addition, long-term total sleep deprivation increases several serum Ig classes (IgM, IgG, IgA). Everson was quick to note that these serum types rose in total sleep-deprived rats even if no experimental antigens were administered to them. Immune activation despite the absence of invading bacteria and or toxins is a sign of impaired immune function (Opp, Born, and Irwin, 2007, p. 597).
Similarity with Human Studies
Human studies on the effects of sleep deprivation yielded results that are similar to those of Rechtschaffen’s and Everson’s. Almost every research on sleep deprivation in humans found the following effects:
- Weight gain – Sleep loss lowers leptin levels, which increases hunger levels. Someone who does not have adequate rest can gain weight by eating more at night, when the body’s metabolism has already slowed down.
- Mood swings – Insufficient rest increases stress and anxiety levels, causing irritability and short-temperedness.
- Brain static – The brain cannot function effectively if it is working harder to counteract the effects of sleep loss.
- Poor immune system – Given its restorative functions, adequate rest is necessary for a properly functioning immune system (Panella, 2002, pp. 68-70).
Conclusion
In the context of sleep deprivation, the saying “an ounce of prevention is worth a pound of cure” certainly holds true. If only they had sufficient rest, many people would actually save on enormous hospital bills and medicines for the treatment of serious ailments such as hypertension, diabetes and ADHD. The human body has the capacity to repair itself. However, the unhealthy lifestyle associated with modern existence prevents this faculty from working.
No matter how busy a person is, he or she must never neglect his or her health. After all, it would be impossible for him or her to work if he or she is sick. In addition, the high costs of medicines and hospitalizations would severely drain him or her financially. In the end, it is still easier to get enough sleep than to raise money for medical treatments.
References
- Andreassi, J.L. (2007). Psychophysiology: Human Behavior and Physiological Response (5th ed.). Mahwah, New Jersey: Lawrence Erlbaum Associates, Inc. Publishers.
- Opp, M.R., Born, J., & Irwin, M.R. (2007). Sleep and the Immune System. In R. Ader (Ed.), Psychoneuroimmunology (pp. 579-618) (4th ed.). Burlington, Massachusetts: Elsevier Academic Press.
- Panella, V. (2002). The 26-Hour Day: How to Gain at least Two Hours a Day with Time Control. Franklin Lakes, New Jersey: Career Press.
- Timby, B.K. (2009). Fundamental Nursing Skills and Concepts (9th ed.). Philadelphia, Philadelphia: Wolters Kluwer Health.
