Nervous System and Communication among Neuron Cells - Essay Example

Nervous System essay Science is a subject which is driven mainly by man’s need to understand and comprehend the natural order of things so as to ensure that they can grasp the various mechanisms that help in the functioning of the world. The history of the world reflects that the role of the development by man is more often than not in a circular manner, in which the need to understand a natural phenomenon, and the development of the scientific knowledge in the field leads to further research and greater amount of scientific development and research in the long run. The science that is related to the study of neurology and the study of neurons, that is Neuroscience is no different in its evolution. This field of science allows for the study of the functioning of the brain and in relation to this the science of neuroscience has developed in relation to this. Since the beginning of the 20th century neuroscientists have tried to look into and comprehend the underlying function and role of the brain. With the study and analysis of the functioning of the brain it was discovered and established that the basic building block of the brain on the basis of which the organ functions is the neuron. The neuron is a unique cell that is found in any multi-cellular organism and this performs certain special functions (Van Swinderen, B. 2005). It has been observed that the scientists have over the years continued their search on the subject matter, and the area of research has only grown vast as time has progressed. The scientists have conducted research which has revealed that the microscopic neurons together form the neural network that functions in all the parts of the body and it forms the communication channel in the body through which the commands of the brains are implemented (I. Segev and M. London, 2000). The main concern of the scientists following this discovery of the neurons was to understand and comprehend the working of the neurons and how they communicate with the other neurons. The research and study of the neurons has been developing and evolving for nearly a century now, and till date the neuroscientist are discovering new functions and working of the of a neuron in the body (Tsatmali, M., E.C. Walcott, and K.L. Crossin 2005). The focus today is to ensure that there can be developed a clear understanding of the communication function and ability of a single neuron (Seth, A.K. 2005). The scientists are today focusing on understanding neural functions in accordance to the new theories of communication that are being evolved and developed with time so as to ensure that there is a clear understanding established about the role of the neuron in the communication in the body (M. London and M. Hausse 2005). In the following paper there shall be established a clear understanding about the function of the neuron in communication system of the body as well as develop a clear understanding of multiple sclerosis and its effect on the neural system’s working in the body. In the year of 1930s it was theorized by scientists such as Hodgkin and Huxley that the communication that takes place among the neuron cells in the body is through the use of electrical medium, and once it had been theorized, there were experiments conducted to prove that this was true (Andretic, R., B. van Swinderen, and R.J. Greenspan 2005). Thus, it has been observed that once this was established that the engineers have been a vital part in the evolution of the field of neuroscience under the heading of biology. The emphasis on the studying and analysis of the electrical component was established through the development of neural networks which was composed mainly of the electrical engineers in this interdisciplinary field of biological science. Engineers mimic the ability of the brain to learn through simplistic models of neurons and networks of them. Due to these developments there has been observed that the study in the area of Signal processing has much improved. The figure that has been represented in the section below (Figure 1), reflects the various sections of a single neuron which is the basic cell that is the integral part of the communication system in the body. The main section of a neuron is comprised of mainly three sections, the dendritic tree which is the branch like top, the soma which is the body of the neuron and the axon which is the bottom part of the neuron. The main function of the dendritic is that of receiving the message, and is the input section of the neuron, where as the axon is the section of the message which allows for the message to get transferred and is the output section of the neuron. The axon of a neuron helps the message transfer to the dendritic section of the next neuron. The term synapse is one which is used to describe the interface section of the axon of each axon, whereas the gap between the synapse and the surface of the dendritic of the next neuron is known as the synaptic cleft in a chain (Seth, A.K., O. Sporns, and J.L. Krichmar 2005). The research has reflected that the almost all the signaling that occurs in the brain is based electrochemical transfers that is carried out by the neurons. The axon and the dendritic play the most significant role in the communication of the information, as has already been mentioned in the section above. When a message has to be transferred the axon synapse secretes chemicals which is known as neurotransmitter and they then travel across the space between the axon and the dendritic, that is, the synaptic cleft and then it has either a excitatory or an inhibitory effect on the dendritic. In the excitatory case, the dendrite generates an electrical current by altering properties of the cell membrane (Edelman, D.B., and E.W. Keefer 2005). The size of the electrical pulse falls off as a function of the distance to the cell body. In the inhibitory case, the dendrite alters the properties of the cell membrane to have a shunting effect and suppress any currents generated nearby. One neuron may have thousands of synaptic inputs! Figure 1- Various parts of a neuron cell The importance of communication cannot be emphasized upon enough, and is it vital for the survival of an organism to ensure that there is communication within the various parts of the body. This is usually achieved through the transferring of chemicals from one cell to another. As has already been mentioned in the section above the role of the neuron cell is the most vital when the transferring of messages is taking place (Siegel, J.J., D.A. Nitz, and V.P. Bingman 2005). The chemicals which carry the message, known as the neurotransmitters and stored in the vesicles of the neuron cell, and are secreted by the axon of the neuron cell as and when required in response to any stimulus that the cell may receive, when there occurs an action which leads to the membrane depolarization in the neuron cell (Izhikevich, E.M. 2004). Once this has occurred, the neurotransmitter cells fuse across the space between the axon and the dendritic, where there is observed that there is mainly an influx of calcium and sodium ions into the cell, where the calcium ions in the cell activate the a certain enzyme, that is, the protein kinase C (PKC) in the cell which helps ensure that there is no fusing of the chemicals takes place with the cells of the neurons so that the message is transferred in an uninterrupted manner (Greenspan, R.J., and B.J. Baars 2005). It acts on the cytoskeleton and helps ensure that it breaks down so that the fusing of the chemicals occurs in a smooth manner, and this is assisted by the calcium which also acts upon the cytoskeleton to break it down and accelerates the exocytosis in the cells. Once the neurotransmitter has fused out, it then defuses with through the synaptic cleft fuses with the dendritic of the next cell and the process continues till the entire chain is completed. This is the method through which the communication between the cells in a multi-cellular organism is carried out. There are some diseases that have a direct effect on the neural system of the body, where they can hamper the functioning of the neurons in the short run as well as permanently (C. Koch and I. Segev 2000). One such disease is Multiple Sclerosis, which is also known as disseminated sclerosis which has a direct effect on the neurons of the body. It is an inflammatory disease which affects the cells of the brains and the spinal cords. In the people who are affected by the disease experience damage the fatty myelin sheath of the axons of the neuron cells of the brain and the spinal cords. It leads to a slowing down of the reactions and even leads to scarring in the body due to the damage of the fatty myelin sheath (Andretic, R., and P.J. Shaw 2005). The disease is seen to have an adverse effect mainly on young adults, and it has been observed that this disease is more commonly found among the female population and is not frequently occurring among the male population. It was first discovered and established in the year of 1868 by the scientist Jean Martin Charcot. The disease is not very prevalent and may affect 2 to 150 people per 100,000 in a population. The main effect and impact of the disease is seen to be on the neuron cells that are the basic fundamentals of the communication system in an organism. The disease is seen to have a direct effect on the neuron cells of the brain and the spinal cord and hampers the cells from communicating with each other. As has been described in the section above, the communication that takes place between the various cells is carried out by the axons which carry the electrical message from one cell to the next (Krichmar, J.L., and G.M. Edelman 2005). The axons are covered in a insulating material known as the myelin, and the disease, that is Multiple Sclerosis is seen to have a direct effect on the myelin. When one is experiencing this disease the immune system of the body stops functioning in the normal way and in turn starts to attack the myelin that is covering the axons in the body. Due to the loss of the myelin the axons are unable to function in a proper manner and this leads to the breakdown of the communication channels in the body as the axon is no longer able to communicate the signals in an effective manner. The name of the disease is reflective of the effect that it has on white cells of the brains, as it leaves scars on the cells and the tissues of the body, mainly the brain and the spinal cord which has the maximum concentration of myelin in the body. The scientists are till date debating over the cause of the disease where some believe that it is the result of the environmental causes whereas others believe that it is hereditary in nature. A person who is suffering from this disease usually complains about the changing sensations, which is inclusive of decrease in the sensitivity or at times complete loss of sensation. At times the patients also complain of tingling sensation or numbness in certain areas and parts of the body. This is usually accompanied by muscle weakness and difficulty in movement is experienced by the patients. Patients also reflect trouble in the areas of speech, or maintaining balance, and might have trouble in visualizing and loss of control over bladder and others. The symptoms of the disease are not well defined although it is specified that when it worsens it leads relapses where the person looses all control over the body parts. Thus, it leads to a complete breakdown of the communication system of the neural system in the body. References Krichmar, J.L., and G.M. Edelman 2005, Brain based devices for the study of nervous systems and the development of intelligent machines. Artificial Life 11:63-77. 555. Van Swinderen, B. 2005, The remote roots of consciousness in fruit-fly selective attention? BioEssays 27:321-330. Seth, A.K., O. Sporns, and J.L. Krichmar 2005, Neurorobotic models in neuroscience and neuroinformatics, Neuroinformatics 3:167-170. Siegel, J.J., D.A. Nitz, and V.P. Bingman 2005, Spatial selectivity of single units in the hippocampal formation of freely moving homing pigeons. Hippocampus 15:26-40. Tsatmali, M., E.C. Walcott, and K.L. Crossin 2005, Newborn neurons acquire high levels of reactive oxygen species and increased mitochondrial proteins upon differentiation from progenitors. Brain Res. 1040:137-150. Greenspan, R.J., and B.J. Baars 2005, Consciousness eclipsed: Jacques Loeb, Ivan P. 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