Sleep Is One of the Most Important Functions - Assignment Example

?Sleep Sleep is one of the most important functions that goes on in the human body, even though we are still uncertain as to exactly what happens when we sleep. Sleep is often characterized as a paradoxical state in that the exterior is essentially “paralyzed” and inactive, where as underneath the surface, the body is very active. There are multiple theories regarding as to why sleep is necessary. During sleep, the brain sorts out and processes all the information that was observed for the day. This is one of the main points behind dreams is the mind is attempting to find meaning behind the daily experience and encode it. Another reason for sleep is that it serves as physiological maintenence. During sleep, muscles and other damaged cellular components use the time to repair and regenerate. Another important feature of sleep physiology is the notion of an internal clock, or our natural circadian rhythms. Circadian rhythms are observed in almost all living things. This internal clock serves as regulating when to be active and using energy compared when the organism should be resting to conserve energy. The cycle occurs once per day. In particular, the effect can be seen with the impact of the changing between daylight and nighttime. This can be seen by the effects of sleep and light on the secretion of certain neurochemicals and hormones such as melatonin. Sleep occurs in distinct phases, which is characterized by a change in brain wave activity as well as some physiological changes. There are 2 main phases of sleep: non- rapid eye movement and rapid eye movement. Stage 1 is characterized as the light sleep that is predominated by theta waves that lasts between 5-10 minutes. The second stage lasts around 20 minutes and sleep spindles begin to form, which are rapid bursts in brain activity. The third stage is characterized by delta waves and is in between light and heavy sleep. Stage four is deep sleep, which is again characterized by an increase in delta waves. Stage 5 is the deepest stage of sleep and this is where REM occurs. REM stands for rapid eye movement. The most vivid dreaming occurs during this stage of sleep because it is the deepest stage of sleep. REM usually occurs between 4 and 5 times throughout the entire night. The mind is extremely active during this period with levels of neurological activity being similar to that of being awake. Theories show that REM is important in not only maintaining neurological activity, but also for memory processing. Sleep disorders can be caused by a majority of cases and there are a variety of them. Sleep apnea is a disorder in which a person physically stops breathing during sleep. Insomnia is where a person cannot fall asleep easily, therefore feels the effects of sleep deprivation. Too little and too much sleep can result in some diseases and conditions. These can range from diabetes to certain types of cancers. Stress One of the most important topics in health psychology, stress is a multidisciplinary topic that goes into not only the cognitive effects of stress, but also the physiological effects of stress. Principally there are two main chemicals, which are mediated in stress responses. Cortisol and norepinephrine release are triggered when a person is experiencing a stressful situation. These chemicals function as a stimulus, which heightens physiological response to handle the incoming threat or danger. Stress has been linked to a multitude of physiological problems. Prolonged stress can lead to sleep deprivation and insomnia, which leads to a host of its own physiological problems. Increases in blood pressure and pulse can lead to heart disease and cancers. Stress can also affect the endocrine system because too much stress leads to over activity in this system, which can lead to certain types of cancers as well as certain types of diabetes. Increased stress can also lead to compromising the immune system, which can make a person more susceptible to developing infection and illnesses. It has also been shown that stress has a physiological response on organs such as the adrenal glands, which become enlarged as the result of the release of stress chemicals. In the brain, stress is mediated by the adrenal cortex and hypothalamus. These are the neural structures, which are responsible for mediating the stress response and causing the release in the chemicals. Too much stress and prolonged excretion of the chemicals can have negative consequences to portions of the brain. It can lead to damage in the brain and problems with encoding/storage of information. Specifically, cortisol has been linked to causing damage in the hippocampus and can lead to cellular death of neurons in the brain. On the cognitive level, stress is defined as when a person’s perceived coping resources are not sufficient enough for a person’s perceived demands. In this case, a person reaches stress, which can lead to a host of psychological responses such as anxiety attacks, mood swings, depression, etc. Stress also makes it difficult for a person to function cognitively. Stress has also been known to effect decision-making abilities. There are many maladaptive and adaptive coping measures, which can develop as a result of stress, but are all inherently unique to every individual. With all the negativity, stress can also have positive effects on a person. Originally, stress is a physiological mechanism, which is designed to activate and protect a person from harm. Thus, when a person is stressed they enter a heightened state of awareness and certain physiological responses increase to prepare for an incoming threat. As a result, some stress reactions actually serve an individual in becoming more cognitively and physically readied. Drugs and Reinforcement Drugs can act in a multitude of different ways depending on the active ingredients in the drug as well as what part of the body they are designed to target. There are two important terms to look at when looking at pharmacology. A person can develop a psychological addiction to a substance in which the rewarding feeling and the need for the drug are created through the use of learning such as classical conditioning or operant conditioning. Physiological addiction occurs when the drug to the point has modified a person’s body where withdrawal symptoms occur once the drug is taken away. The range of symptoms from withdrawal can range from minor effects to death. The reason drugs can become addictive is due to the way in which they bind to the receptors in the body. Depending on the type of drug, there are a multitude of different effects that can occur. When it comes down to drug abuse, most are addicted to the drug, either psychologically or physiologically, because they like the euphoric effect that comes as a result of using the drug. As stated previously, the mechanism of action for a drug is important when looking at how addictive the drug is going to be. In positive reinforcement, a person is able to achieve a greater effect with the more drugs that they use. This is the start of tolerance. In the case of drug addicts, they have to take in more and more of the drug in order to achieve the same desired effect of euphoria. This again serves as a reinforcer, which can lead to the physical and/or psychological addiction. Once addiction has set in, a person must be weaned off the drug in order to prevent the withdrawal effects from occurring, depending on the medication. In some cases, such as in methamphetamine, a drug substitute such as Methadone must be used in order to help mediate the addiction. Depending on the severity, some people can never make it off the methadone; therefore it serves as a custodial drug. The neurons can also be altered by long term drug use as far as either increasing or decreasing the levels of secretion of neurotransmitters to abnormal levels. One of the most widely used drugs in the world is marijuana. There are specific receptors called CB1 and CB2, which exist in the brain stem and on the spinal cord. Only the THC in marijuana can interact with these receptors. Once the THC enters the system, it interacts with these receptors. It causes the release of large amounts of dopamine, which are a pleasure producing neurotransmitter. In addition, marijuana can play host to a number of physiological effects such as hallucinations, both auditory and visually, as well as conditions such as vascularization in the eye, decreased blood pressure, hunger, etc. Drug use is also impacted by psychological and cultural norms within society. Certain drugs are highly frowned upon such as methamphetamines, whereas drugs such as alcohol, cigarettes, and marijuana are commonly accepted as recreational drugs. In addition, the accessibility to the drug plays a role in the usage in a population. The easier it is to access, the more widespread the use is. In some cultures, the use of alcohol and tobacco at parties is termed the “cool thing” thus adolescents cling to this construct in order to meet the established cultural norm. References Billiard, M, & Kent, A. (2003). Sleep: physiology, investigations, and medicine. New York, NY: Kluwer Academics. Cooper, C, & Dewe, P. (2004). Stress: a brief history. Malden, MA: Blackwell Publishing Ltd. Goldberg, R. (2010). Drugs across the spectrum. Belmont, CA: Wadsworth. Mehling, R, & Triggle, D. (2003). Marijuana. New York, NY: Chelsea House Publishers. McCarty, R. (2002). Stress: neural, endocrine, and molecular studies. New York, NY: Taylor and Francis Group. Schenck, C. (2007). Sleep: the mysteries, the problems, and the solutions. New York, NY: Penguin Books. Read More