Marijuana and Tobacco: Effects on the Nervous System - Research Paper Example

Marijuana and Tobacco: Effects on the Nervous System I. Introduction In this work, we focus on the effect of marijuana and tobacco on the nervoussystem. The nervous system covers a great part of the human body, human body processes and the thinking and emotional processes. Marcovitch pointed out that the nervous system covers the brain, the autonomic part of the nervous system, the somatic system, and the complex systems of the human body (489-490). The autonomic part of the nervous system controls the automatic or unconscious control covering the heartbeat, muscular control of the blood vessels, digestion, and glandular (Marcovitch 490). The somatic system of the nervous system controls the skeletal muscles covering the activation of limbs, urination, and the vaginal muscles as well as our survival response like reflexes (Marcovitch 490). The nervous system also controls our ability to experience emotion, pleasure, anxiety, frustration, and conduct intellectual activities (Marcovitch 490). The thinking process as well memory, visual perception, thought, and speech are also controlled by the nervous system even if their full operations are not yet well understood (Marcovitch 490). Meanwhile, the British Medical Association defines the nervous system as the body system that stores information and is in the overall control of the body (394). According to the British Medical Association, “the brain and spinal cord form the central nervous system (CNS)” (395). The sense organs of the body send information to the central nervous system through “nerves that fan out from the CNS to the entire body” (British Medical Association 395). Like Marcovitch, the British Medical Association identified that the two of the most important sub-systems of the nervous system are the autonomic nervous system and the somatic nervous system (395). The autonomic nervous system is concerned with the unconscious or automatic regulation of the internal body while the somatic nervous system is responsible for control of the muscles or voluntary movement (British Medical Association 396). Disorders of the nervous system include impairments of the sensory, analytical or memory functions(British Medical Association 396); deafness; numbness; anosmia; agnosia; amnesia; aphasia; dysarthria; ataxia; and of motor function (British Medical Association 396). Nevertheless, “the overall function of the nervous system is to gather and analyse information about the external environment and the body’s internal state, and to initiate appropriate responses, such as avoiding physical danger.” II. Tobacco According to Mackey and Eriksen, “tobacco is packed with harmful and addictive substances” (32). Mackay and Eriksen pointed out that “evidence has shown that all forms of tobacco cause health problems throughout life, frequently resulting in death or disability” (32). The work of Mackay and Eriksen, however, does not highlight an effect of Tobacco on the nervous system even if the World Health Organization was the publisher of their work. Instead, Mackay and Eriksen have emphasized that “smokers have markedly increase risks of multiple cancers, particularly lung cancer, and are far greater risk of heart disease, strokes, emphysema and many other fatal and non-fatal diseases.” Further, according to Mackay and Eriksen, “women suffer additional health risks” because “smoking in pregnancy is dangerous to the mother as well as to the fetus, especially in poor countries where health facilities are inadequate” (32). According to Mackay and Eriksen, “the first conclusive evidence on the dangers of passive smoking came from Takeshi Hirayama’s study on lung cancer in non-smoking Japanese women married to men who smoked” (32). According to Mackay and Erikson, “the risk of lung cancer exposed to passive smoking is increased by between 20 and 30 percent, and the excess risks of heart disease is 23 percent” (32). Children are at particular risk from adults’ smoking and that the “adverse health effects include pneumonia and bronchitis, coughing and wheezing, worsening of asthma, middle ear disease, and possibility of neuro-behavioral impairment and cardiovascular disease in adulthood” (Mackay and Eriksen 32). Further, pregnant women who are exposed to smoking put her fetus to being harmed and the effects can be compounded when they are exposed to passive smoking after birth (Mackay and Eriksen 32). The Mackay and Eriksen material does not report an effect of tobacco on the body’s nervous system but had stressed on the physical effects of tobacco on the body as well as the linkage of tobacco with cancer, heart disease, and respiratory illness. Yet, a report of the Canadian Medical Association Journal as early as 1921 indicated that smoking indeed affects the nervous system (774). The 1921 Canadian Medical Association Journal report narrated that a meeting of the American Society for Pharmacology and Experimental Therapeutics, experiments showed that smoking “raised the threshold and lowered irritability” (774). The threshold in the experiments reported by the Canadian Medical Association Journal refers to sensory thresholds determined by the Martin method of quantitative faradic stimulation with a higher threshold supposedly indicating low irritability. The lower irritability or higher threshold was also interpreted to mean that “smoking had a stimulating effect” (Canadian Medical Association 774). According to the Canadian Medical Association Journal, “the depressant action of smoking, however, was more marked than its stimulating effects” (774). Further, the Canadian Medical Association Journal also reported that the effect of smoking is similar in some respects to resting (774). In particular, the Canadian Medical Journal said that the “stimulating action of smoking when one is depressed and the soothing effect when feels nervous or irritable is generally acknowledged and accounts for the widespread use of tobacco” (774). In 1970, an empirical/experimental study confirmed that tobacco affects the cerebral cortex and has determined that “nicotine is the principal pharmacological constituent of tobacco smoke as far as effects on the central nervous system are concerned” but the study inferred on experiments on cats. However, in 2003, the study of Rose and colleagues investigated the effects of acute nicotine administration and smoking on the brain. In the said study, healthy volunteers were exposed to smoking conditions and were assessed. The 2003 study of Rose and colleagues concluded that “nicotine influences brain regions involved in arousal and reward and suggest specific functional systems that may be linked to motivationally significant aspects of tobacco dependence”(323). The study pointed out that the brain regions, “such as the pons, midbrain, and thalamus, contain high densities of nicotine receptors” that can explain the effect of tobacco on the brain or the nervous system (330). Further, in an August 2010 update, the National Institute on Drug Abuse (NIDA) reported that “upon entering the bloodstream, nicotine immediately stimulates the adrenal glands to release the hormone epinephrine (adrenaline)” (1). The National Institute of Drugs explained that “epinephrine stimulates the central nervous system and increases blood pressure, respiration, and heart rate” (1). III. Marijuana In 1998, it was estimated that more than 5.5 million adults in the United States smoke marijuana on a weekly basis (Steinherz and Vissing 59). Although marijuana has been in use for at least 4,000 years, it was in 1964 that Israeli chemists isolated the principal psychoactive ingredient of marijuana: delta-9-tetrahydrocannabinol Delta-9-THC (Steinherz and Vissing). According to Steinherz and Vissing, the substance mentioned is the substance “that produces the ‘high,” feeling of intoxication, that users crave. However, marijuana or cannabis contains more than 400 chemical compounds, “of which 60 are cannabinoid---psychoactive compounds that can be extracted from the cannabis plant, or produced within the body after ingestion and metabolism of cannabis” (Steinherz and Vissing 59). Cannabis, like the nicotine from cigarettes, is normally inhaled (Steinherz and Vissing 60). Thus, according to Steinherz and Vissing, because of this, cannabis has rapid access to the blood system (60). Cannabis and its metabolites are fat soluble or liphophilic and are able to pass through the blood-brain barrier (Steinherz and Vissing 60). The effect of cannabis on the thought processes as well as the entire nervous system is assured because of liphophilic property of cannabis, not even antibiotics or drugs for treating cancer has the liphophilic property which cannabis possess (Steinherz and Vissing 60). Cannabis is able to penetrate the two layers of cells that form the blood-brain barrier: after metabolism in the lungs and liver into the Cannabis metabolites, cannabis moves rapidly to lipid-rich tissues that includes the brain (Steinherz and Vissing 60). One of the most reported feelings under the influence of marijuana is release from stress, loosening of associations and euphoria (Steinherz and Vissing 60). The effect of Marijuana is dose dependent (Steinherz and Vissing 60). However, the specific effects of marijuana vary based on the user’s psychological history, experience, and social setting (Steinherz and Vissing 60). Marijuana or cannabis remain in the bloodstream for a long time and, thus, individuals who use cannabis on a daily basis are more at risks compared to infrequent users (Steinherz and Vissing 60). According to Steinherz and Vissing, numerous investigations have found that marijuana’s “most pronounced are reduced short-term memory, locomotion disorders, altered time sense, paranoia, fragmentation of thought, and lethargy” (Steinherz and Vissing 60). One comprehensive study on cannabis or marijuana is the one by Wodak written in 2002. Wodak reviewed the peer reviewed medical journals on cannabis studies as well the scientific documents of government agencies on marijuana at the international level and based on these, formulated his own conclusions or articulated the conclusions of the scientific medical studies conducted on marijuana or cannabis. According to Wodak, cannabis “precipitates schizophrenia and other psychotic disorders and worsens their course” among vulnerable individuals” (107). At the same time, 15% of schizophrenic patients commit suicide (Wodak 107). It therefore follows that that marijuana possibly contributes to the incidence of suicides. According to Wodak, there are other psychological effects of cannabis. The other psychological effects of cannabis include depression, anxiety and violent behavior (Wodak 107). According to Wodak, the psychological effect of cannabis is understandable because marijuana has up to sixty (60) psychoactive ingredients (107). The Wodak figure of 60 coincides with the figure of Steinherz and Vissing. Wodak emphasized that cannabis or marijuana “is bad for the mental health of many vulnerable people” (107). Wodak also pointed out that cannabis increases the risk of death in people with heart disease (107). The other risks of using marijuana include “impairment of cognitive function, reduced academic achievement, teratogenic effects, immune-suppression, impaired fertility, and increased promiscuity and sexually transmitted diseases in regular users” (Wodak 107). Cannabis also affects cognitive and motor abilities (Wodak 107). According to Wodak, the ill effects of cannabis is “complicated by confounding factors such as alcohol intoxication, although in one UK study of fatal road accidents, no alcohol was detected in the bodies of 80% of people found positive for cannabis at necropsy” (Wodak 107). According to Wodak, the current medical view is that the “separate effects of alcohol and cannabis on psychomotor impairment and driving performance are approximately additive” (107). Cannabis produces dependence in about 10% of users and in about 50-90% of regular users (Wodak 107). Nevertheless, Wodak pointed out that “evidence suggests that use is not increased by less intensive control” on the use of cannabis (Wodak 106). According to Wodak, “in the 11 American states that effectively decriminalized cannabis use in the 1970s, use has not risen beyond that experienced by comparable states in which it is prohibited” (106). Further, “the Netherlands for all intents and purposes decriminalized cannabis 25 years ago, but the prevalence there has remained roughly parallel to that in Germany and France and well below that in the United States” (Wodak 106). IV. Conclusion: Comparing Marijuana and Tobacco Based on the our discussion in this work, the key difference between marijuana and tobacco is that while the effect of marijuana is primarily on the nervous system, including on the perceptual and thought processes, the main effects of smoking on the human body involve more the carcinogenic effects of nicotine and smoking’s effects on the lungs and respiratory system. This is not to say, however, that smoking or nicotine has no effect on the nervous system. In this work, it has been pointed for instance that the Canadian Medical Journal as early as 1921 has reported that the smoking has an effect on the nervous system (774). Further, there are also studies that have indicated that tobacco indeed affect the nervous system. However, based on information immediately available, the effect of tobacco on the body’s nervous system is not very extensive. It appears that much of the effect of tobacco on the body’s nervous system is basically limited to keeping the human body in a more relaxed or less irritated state even with the stimulant properties of tobacco. In contrast, the effects of marijuana or cannabis on the nervous system appear more extensive. Given these, it is likely that the effects of marijuana and tobacco on teenagers will not be different from its effects on adults. Of course, most likely, marijuana and smoking will not likely have many effects on teenagers with regard to stroke and heart disease but the other effects of marijuana on the nervous system will apply. In the case of tobacco, smoking will continue to be habit forming for teenagers given its relaxing effects as teenagers face the stresses of life. Work Cited British Medical Association. Illustrated Medical Dictionary. London: Dorling Kindersley, 2007. Canadian Medical Association Journal. “Effect of Tobacco Smoking on the Nervous System.” Canadian Medical Association Journal 11.10 (1921): 774. Hall, G. H. “Effects of Nicotine and Tobacco Smoke on the Electricity Activity of the Cerebrex Cortex and Olfactory Bulb.” British Journal of Pharmacology 30 (1970): 271-286. Mackay, Judith and Michael Eriksen. The Tobacco Atlas. Geneva: World Health Organization, 2002. Marcovitch, Harvey. Black’s Medical Dictionary. 41st ed. London: A&C Black Publishers Limited, 2005. National Institute on Drug Abuse. “Cigarettes and Other Tobacco Products.” An Information Sheet. U.S. Department of Health and Human Services: National Institutes of Health, August 2010. Rose, Jed, Frederique Behms, Eric Westman, Edythe London, Thomas Hawks, Timothy Turkington, and R. Edward Coleman. “PET Studies of the Influences of Nicotine on Neural Systems in Cigarette Smokers.” American Journal of Psychiatry 160.2 (February 2003): 323-333. Steinherz, Karen and Thomas Vissing. “The Medical Effects of Marijuana on the Brain.” 21st Century, Winter 1997-1998 (1998): 59-69. Wodak, Alex. “Cannabis Control: Costs outweigh the Benefits.” British Medical Journal 324 (2002, 12 January): 105-108. Read More