How The Animal Experimenting Contribute to OurUnderstanding of Human Brains - Essay Example

Why do scientists use animals in research How does it contribute to ourunderstanding of human brains Introduction: Medical researchers first study the disease or a health problem thoroughly before they develop different ways of treating it. There are some diseases and health problems which entail method that can be studied only in a living being. In the medical and psychological field, animals are frequently used for researches instead when it cannot be done on humans due to some impractical or ethical issues. A great deal of our understanding of neurons and the human brain has happened due to through animal research which may have proved to be difficult otherwise. There are many reasons why researchers choose animals for their research. Firstly, there are biological similarities between animals and humans. Thus, they share various similar health problems and both have short life-cycles which makes it easy to study the whole life-span all along or even across quite a few generations. Moreover, scientists can also control the environment around the animals very easily such as through control diet, temperature or lighting, etc., which may be very difficult to do with humans. Though, the main reason why humans are not used to expose to these sorts of experiments is because it is easier to expose animals to health risks for observations of any disease or disorder. Animal Experimenting Animal experiments (also known as vivisection) are defined in the Animals (Scientific Procedures) Act 1986 as any scientific procedures performed on a living animal likely to cause them "pain, suffering, distress or lasting harm." At present, the Act defines an animal as any animal with a backbone; plus the octopus. The approximated number of animals used for experimenting is almost 180 million every year worldwide. Though not every country keeps an estimate; in theUSA, for example, 80% of animals like birds, rats and mice used for research purposes are not included in official figures at all (Dr. Hadwen Trust, 2009). There are two things for which scientists use animals; one is for medical research and the other type generally includes experiments on cells or chemicals and simulations on computers. The experimenting can be done on vertebrates including rats, mice, rabbits, guinea pigs, hamsters, cats, dogs, mini-pigs, primates, goats, sheep, birds, fish, etc. (Dr. Hadwen Trust, 2009). Clinical research is also an important type of research which is basically conducted on humans but it always requires preliminary test result after the completion of animal research studies. Researchers use animals for extensive purposes which involve poisoning; disease infection; wound infliction; use of skin or eye irritants; food, water or sleep deprivation; subjection to mental stress; brain injury; paralysis; surgical disfigurement; induced organ malfunction; genetic modification and associated physical deformity; burning; and electric shocks. Medical Research with Animal Saves Lives (National Institute of Health, 2006) Animal Model Medical Benefit for People Dog Discovery of insulin Monkey Polio vaccine Mouse Rabies vaccine Pig Skin grafts for burn victims Pig Computer-assisted tomography (CAT) scans Rabbit Corneal transplants Rat Carcinogen screening Around the world there are many organizations which are working day and night to understand the human diseases and knowledge. They are using animals extensively for studying the animal as well as human diseases. Although the results from animal research are essential for increasing our knowledge about health and disease in both animals and humans; determining cell and organ function helps researchers design experiments to test new treatments in people as it is similar in all vertebrates. Animals do suffer during the experiment and there are UK laws which define the pain, suffering, distress or lasting harm in Scientific Procedures Act 1986. Still, animals are also capable of enduring physical as well as psychological harms including fear, depression or boredom. There are many sort of extreme suffering which animals can experience during artificial lab environment which may requires handling excessive noise or light. There are many scientific objections present against animal experimenting, mainly because of differences of species and the artificial induction of diseases, which may be dubious to humans. Progress in the treatments of diabetes, heart surgery transplants and leukemia amongst others; have been rendered possible because of the use of animals in scientific studies. Some more discoveries are shown in the following table: Medical Research that Helps Animals (National Institute of Health, 2006) Discovery How it Helps Animals Research on viruses Dog parvovirus vaccine Research on reproduction Breeding programs for endangered species (like pandas, white tigers) HIV/AIDS research Cat leukemia vaccine Surgical research Dog heart valves, hip replacements Chronic disease treatments Diabetes, heart disease treatments for pets Research done on animals has resulted in some major developments in the world of medicine. This basic knowledge supports the teaching of medicine and veterinary medicine. It has been undoubtly instrumental in the constant progress of medical advances regarding both human and animals. It is no embellishment to say that almost every form of usual medical treatment, such as drugs, vaccines, radiation or surgery, rests in part on the study of animals (US Department of Health and Human Services 1994). Although now researchers are finding other ways than animals, no one can deny the fact that animals are highly accurate model substitutes for humans (Royal Society, 2002). Nevertheless, sometime experimental design fails to find out the teratogenic effects; but is successful in detecting the direct effects. Another great similarity is that many drugs produce the same effects on animals as well as on humans; also same treatment is used such as antibiotics and tranquillizers. The last two decades have a lot of examples which the whole revolution of biology witnessed such as sequencing of the human, mouse and fly genomes (Royal Society, 2002). A lot of research has been done on describing the role of genes and gene products in several diseases, plus providing. The knowledge now available from the sequencing of the human, mouse and fly genomes has enabled genetic modification of animals to produce highly specific models of diseases, helping to identify disease pathways and aid the development of new therapies insight on why some animal respond to some medicines better than other artificial ones (Royal Society 2001). Many challenges to the healthcare systems of both developed and developing countries exist that would benefit from the use of animals in research from (Royal Society 2001) For example: Drug-resistant infections, which are a major problem in both developed and developing countries, frequently involve examination of disease progression and research could benefit from the use of animal models such as genetically modified mice. Mental illnesses, especially depression, schizophrenia and anxiety, which require a holistic approach, involving molecular, cellular and whole animal studies. Better treatments for diseases of bone, joints and the immune system, all of which involve complex interactions throughout the body. Treatment of diseases of genetic origin, such as Duchenne muscular dystrophy, which could utilize genetically-modified animals to mimic human patients. Blindness and deafness, which involve analysis of these functions in living research subjects. HIV infection and AIDS, with animal models of the disease required to develop and test possible vaccines or antiviral agents before trials can be safely conducted in humans. Senile dementia and other complications of old age, where the cause and progression of these conditions is poorly understood at present, and require detailed examination of the brain and nervous system in animal models. (Royal Society 2001) Lesion Studies A brain lesion has been defined as an area in the brain which has been damaged followed by a loss of particular function. Lesion studies present us with ways to verify specific brain structures necessary roles in certain functions. In order to study which area defines which particular brain function, research is done by removing those parts in the brains of animals i.e. creating lesions and then comparing the before and after changes in behavior, feelings, perception etc. Lesions are generally formed by destroying brain tissue by contacting a small wire to the area of interest. This area when acquire electricity is heated and then destroyed; a similar form of technique is also used on humans to lessen symptoms of some diseases but is largely used for research on animals. Lesion studies on animals such as monkeys and dogs produce the same behavioral damages as in humans. One advantage here is that as the brain uses electricity to perform its tasks, thus studying voltage changes can be useful in finding out certain things such as the deterioration of the sensory system in older people (Willott, 1999). One example of this is that when parietal lobe has been damaged in both monkeys and humans, it results in visual disorientation where the sufferer is unable to gauge the distances between themselves and objects near them. The main difficulty faced here was that anesthetization prevented stimulation of the parietal areas in monkeys. In time, the researchers found that these cells responded to the visual stimuli only in certain conditions (Rovee-Collier, Hayne, & Colombo, 20016). Some functions require information from different areas of the brain to work properly such as the receptive fields before any saccadic movement are found to be located in the lateral interparietal area (LIP) while the anterior interparietal area (AIP) responds to the size and direction of the object; when in actuality they are located a few centimeters from each other (Bear, Connors, & Paridiso, 2006). Therefore, it can be seen that experimental studies on animals can be useful in determining the ability of the brain to recuperate from damage. Damage to the hypothalamus, for instance, results in the impairment of thermoregulation in animals; the same may be correct for humans also, who may lose this ability as they age. On the other hand, doing this kind of research on humans may cause irreversible damage to the brain which is unacceptable. Cognitive research for memory had had great influence because of lesion studies such as in the study of amnesia and Alzheimer's diseases. Animal lesion research involves putting a section of the brain temporarily or permanently out of action and then studying the effects on performance (Gazzaniga, & Bizzi, 2000). The limbic system consists of two structures called amygdala and hippocampus; both of these are significant in emotions and memory, respectively. Amygdala controls our negative emotional reactions such as fear, anger, stress, etc and plays a part in the fight or flight reaction (Figley, Nash, 2006). Thus, it can produce adverse reactions which can be bad for survival. Hence, a lesion on this part causes loss of fear and anger. Although, the hippocampus is also involved in the process of fear i.e. hippocampal lesion also causes elimination of fear expressions. It is also important in forming new memory and in retaining memory overall. It is also involved in the process of spatial and most probably, contextual information. Surprisingly, in rabbits instead of retardation in the learning speed; bilateral hippocampal lesions have been seen to have the impact on rabbits which then learn faster than normal rabbits. Still, it can cause severe damage to trace conditioning. What is confusing here is that hippocampal lesions also impair sensory preconditioning which is more of a motor learning function. Amygdala, on the other hand, is involved in the stimulation of relevant emotional and social behavior. A great amount of study has been conducted on the amygdale of animals in relation to emotion. Behavioral impairments are a result of lesions on the specific area of the amygdala alone. It has the power to influence memory by altering consolidation in the hippocampus. It is interesting to note that electrically stimulating the amygdale results in improved attention in animals and fear in humans. Amygdala is also known to eradicate the learned intuitive responses such as the heart rate and the occurrence of learned fear is similar in rabbits, rats and humans (Bechtel, 2007). Research is being carried out on neural transplants on humans as well as on animals and it has been found that fetal brain tissue can be easily transplanted into an aged rodent's brain (Gluck, & Myers, 2001). But the extent to which humans can benefit from such research hasn't been estimated as yet. Anyhow, lesion studies provide insight into the functioning of the brain in relation to its psychological aspects. Conclusion The rate at which development occurs in the world of research varies as we don't know what we are going to find and how it is going to affect the human race. Moreover, the knowledge scientists have up till now is not enough to test latest treatments and surgical techniques on humans directly; we need to have a medium. This medium is provided by the animals; it may be wrong ethically but in the long run, the benefits outrun the loss. After all, humans are the only species able of taking the needs of other species into consideration. References Ahmad-Annuar A Tabrizi, S J & Fisher E M C (2003) Mouse models as a tool for understanding neurodegenerative diseases. Current Opinion in Neurology 16: 451-458. Bear, M. F., Connors, B. W. & Paradiso, M. A., (2006). Neuroscience: Exploring the brain. Location: USA. Publisher: Lippincott Williams & Wilkins. Bechtel, W., (2007). Mental Mechanisms: Philosophical Perspectives on Cognitive Neuroscience. Location: USA. Publisher: CRC Press. Dr. Hadwen Trust. (2009). Frequently Asked Questions. Retrieved from /www.drhadwentrust.org/faqs Figley, C. R., & Nash, W. P., (2006). Combat stress injury: theory, research, and management. Location: USA. Publisher: CRC Press. Gazzaniga, M. S., Bizzi, G. (2000). The New Cognitive Neurosciences: Second Edition. Location: USA. Publisher: MIT Press. Gluck, M. A., & Myers, C. E. (2001). Gateway to Memory: An Introduction to Neural Network Modeling of the Hippocampus and Learning. Location: USA. Publisher: MIT Press. National Institute of Health. (2006). Medical Research with animals. Retrieved from http://science.education.nih.gov/AnimalResearchFS06.pdf. Rovee-Collier, C. K., Hayne, H., Colombo, M. (2001). The development of implicit and explicit memory. Location: Amsterdam. Publisher: John Benjamins Publishing Company. Royal Society (2002), Statement of the Royal Society's position on the use of animals in research. The Royal Society: London http://www.royalsoc.ac.uk/files/statfiles/document-164.pdf. US Department of Health and Human Services, Public Health Service (1994). Animal Welfare Information Centre Servicenewsletter, Volume 5, Summer 1994. http:www.nal.usda.gov/awic/newsletters/v5n2/5n2phs.htm. Willott, J. F., (1999). Neurogerontology: Aging and the nervous system. Location: New York. Publisher: Springer Publishing Company. Read More