Organisation of the parasympathetic nervous system Unlike in the sympathetic nervous system where the cell bodies are found in the thoracic and lumbar spinal cord, the cell bodies of the parasympathetic are found in the cranial and sacral regions. In the cranial region the cell bodies are found in the medulla, pons and midbraine. These ganglionic neurons form four cranial nerves; oculomotor nerve, facial nerve, glossopharyngeal nerve and vagus nerve. In the sacral region, the cell bodies are found in segments S2 to S4 of the spinal cord and these ganglia distribute to form pelvic splanchnic nerves. Like the sympathetic nervous system, the preganglionic parsympathetic motor neurons make synaptic contact with the postganglionic neurons but these are found in the terminal ganglia, which are located within the wall of the target organs. In comparison to the sympathetic ganglia the terminal ganglia are more peripherally located and are more widely distributed. Another difference is that the postganglionic neurons of the parasympathetic division are short in comparison the sympathetic nervous system. Effects of the autonomic nervous system on visceral targets The innervation of skeletal muscle by the somatic nervous system is always excitatory. Whereas for visceral targets that are innervated by the autonomic nervous system the response can be excitatory or inhibitory. This is because both the sympathetic and parasympathetic nervous system make individual synaptic contacts with the target. For organs that are stimulated during physical activity such as the heart, innervations by the sympathetic division triggers an excitatory response which results in the heart rate increasing whereas, if the parasympathetic division innervated the heart rate it would lead to the heart rate slowing down. However the opposite is true for organs whose activity increases while the body is at rest. For example the parasympathetic division triggers the peristalsis of the gut whereas the sympathetic division inhibits it. During periods of fear and exercise the sympathetic division innervates all the end organs simultaneously and leads to the inhibition of the parasympathetic nervous system. This occurs as it allows the body to prepare for life threatening situations by making it more alert and this response is known as the 'fight or flight response.' This response involves the following things: increase in heart rate, cardiac contractility, blood pressure, ventilation of the lungs, and liberation of glucose into blood. This mass response is essential for survival but it can also be triggered spontaneously during panic attacks.
The parasympathetic nervous system is switched on during periods of rest and unlike the sympathetic nervous system it innervates discrete organs. This allows it to control simple reflexes such as urination in response to bladder distension, salivation in response to sight or smell and contraction of the colon in response to food in the stomach. Both the cardiac and smooth muscle are target tissues that are innervated by the autonomic system. Before discussing how they are innvervated their structure and function will be considered.
As a part of the central nervous system, the neural retina is an ideal model system to comprehend this mechanism because its cellular diversity also results from multipotent progenitors, the retinal progenitor cells (RPCs) [2-4].
Although it was once thought that there was no new generation of neurons in the nervous system, studies have shown that the brain retains neural stem cells (NSCs) into adulthood, and neurogenesis continues to occur....
The nervous system can be understood as the body’s electrical wiring and not unlike a car’s electrical system, when something malfunctions, it affects the entire machine.
The frame represents a way of ordering or controlling a writer's narrative so that the elements of his book, article or essay are presented in an interesting and orderly fashion with an interlaced integrity from beginning to end.
Vignettes, episodes, slices of reality are the building blocks of creative nonfiction - the primary distinguishing factor between traditional reportage/journalism and "literary" and/or creative nonfiction and between good, evocative writing and ordinary prose. The uninspired writer will tell the reader about a subject, place or personality, but the creative nonfiction writer will show that subject, place or personality in action. Before we discuss the actual content or construction of a scene, let me suggest that you perform what I like to call the "yellow test."
The disease is described as the buildup of lipid-containing cells in the internal organs and in the nervous system, mental retardation, and loss of sight.
In this profile, Talese leads readers on a whirlwind cross country tour, revealing Sinatra and his entourage interacting with one another and with the rest of the world and demonstrating how the Sinatra world and the world inhabited by everyone else will often collide. These scenes are action-oriented; they contain dialogue and evocative description with great specificity and intimacy such as the gray-haired lady spotted in the shadows of the Sinatra entourage - the guardian of Sinatra's collection of toupees. This tiny detail - Sinatra's wig lady - loomed so large in my mind when I first read the essay that even now, 35 years later, anytime I see Sinatra on TV or spot his photo in a magazine, I find myself unconsciously searching the background for the gray-haired lady with the hatbox.
So far we have mostly discussed the nonfiction or journalistic aspects of the immersion journalism/creative nonfiction genre. The 5th "R" the "riting" part is the most artistic and romantic aspect of the total experience. After all of the preparatory (nonfiction) work is complete, writers will often "create" in two phases. Usually, there is an inspirational explosion, a time when writers allow instinct and feeling to guide their fingers as they create paragraphs, pages, and even entire chapters of books or complete essays. This is what art of any form is all about - the passion of the moment and the magic of the muse. I am not saying that this always happens; it doesn't. Writing is a difficult labor, in which a regular schedule, a daily grind of struggle, is inevitable. But this first part of the experience for most writers is rather loose and spontaneous and therefore more "creative" and fun. The second part of the writing experience - the "craft" part, which comes into play after your basic essay is written - is equally important - and a hundred times more difficult.
So far in this essay I have named a number of well-respected creative nonfiction writers and discussed their work, which means I have satisfied the fourth "R" in our "5R" formula: "Reading." Not only must writers read the research material unearthed in the library, but they also must read the work of the masters of their profession. I have heard some very fine writers claim that they don't read too much anymore - or that they don't read for long periods, especially during the time they are laboring on a lengthy writing project. But almost all writers have read the best writers in their field and are able to converse in great detail about the stylistic approach and intellectual content. An artist who has never studied Picasso, Van Gogh, Michelangelo, even Warhol, is an artist who will quite possibly never succeed.
Secondly, I will want to assess my competition. What other essays, books and articles have been written about this subject? Who are the experts, the pioneers, the most controversial figures? I want to find a new angle - not write a story similar to one that has already been written. And finally, how can I reflect and evaluate a person, subject or place unless I know all of the contrasting points-of-view? Reflection may permit a certain amount of speculation, but only when based upon a solid foundation of knowledge.