Amblyopia
This paper provides a brief description of amblyopia and discusses current research regarding the motion pathway in individuals with amblyopia.
Amblyopia is a condition in which visual acuity in one eye is greatly reduced. It is caused by lack of stimulation or disuse during visual development (Rose, 1998). Because the eye is not fully developed at birth (Jarvis, 1992, as cited in Rose, 1998), infants need stimulation to complete the visual neural pathway. When one or both eyes are inhibited, for example due to misalignment of one eye (strabismus) or a large difference in refractive power between two eyes (anisometropia), the neural pathway for the inhibited eye develops abnormally, or does not develop at all. At approximately six years of age eye development is complete (Stager, 1990, as cited in Rose, 1998). Before visual development is complete amblyopia can be treated. If it is caught and treated at an early age, normal vision can be preserved (Rose, 1998).
There are several types of amblyopia. Researchers must be aware of the various types of amblyopia because the effects for each are not always consistent. Strabismic amblyopia is caused when the two eyes are out of alignment due to weak musculature. Anisometropic amblyopia is a result of a large difference in refractive power of an individual's eyes. Another form of amblyopia results when visual information does not reach the retina. This is called stimulus deprivation amblyopia. Meridional amblyopia is a result of the diffused images caused by astigmatism. Researchers often discover that there are differences between groups of amblyopes based on type. For example, Levi and his colleagues (1994) discovered differences in vernier acuity between anisomet...
... middle of paper ...
...9-1944.
Hess, R. F., & Anderson, S. J. (1993). Motion sensitivity and spatial undersampling in amblyopia. Vision Research, 33, 881-896.
Hess, R. F., Demanins, R., & Bex, P. J. (1997). A reduced motion aftereffect in strabismic amblyopia. Vision Research, 37, 1303-1311.
Kubova, Z., Miroslav, K., Juran, J., & Blakemore, C. (1996). Is the motion system relatively spared in amblyopia? Evidence from cortical evoked responses. Vision Research, 36, 181-190.
Levi, D. M., Klein, S. A., & Wang, H. (1994). Amblyopic and peripheral vernier acuity: a test-pedestal approach. Vision Research, 34, 3265-3292.
Levi, D. M., & Polat, U. (1996). Neural plasticity in adults with amblyopia [Abstract]. Proceedings of the National Academy of Sciences of the United States, 93, 6830.
Rose, S. E. (1998). Amblyopia: the silent thief. The Journal of School Health, 68, 2, 76-79.
One of the myths was, Polyphemus was in love with a sea nymph named Galateia, a sicilian nereid who had cheated on him with a man named Acis. When Polyphemus discovered this he crushed Acis under a rock. Another myth was the story of Odysseus. This story was when Polyphemus had captured Odysseus one of victorious greek leaders and twelve of his crew members when they were sailing for home from the trojan war. They became captured when they arrived to an unknown island of cyclopes. Odysseus and his men came upon the cave of Polyphemus, and went inside in hopes to steal food while Polyphemus was away tending his flock. Curiosity got the best of Odysseus as he wanted to see what a cyclops looked like. Odysseus and his men hid in the cave waiting for Polyphemus to come back.
Seltzer, Jo. "Ophthalmologists Express Skepticism About Vision Therapy." Stlbeacon.org. N.p., 30 Nov. 2010. Web. 1 Mar. 2014.
Tilikete, C., Rode, G., Rossetti, Y., Pichon, J., Ling, L., & Boisson, D. (2001). Prism adaptation to rightward optical deviation improves postural imbalance in left-hemiparetic patients. Current Biology, 524-528.
The effects of perceptual load on the occurrence of inattentional blindness were demonstrated clearly by experiment. In an experiment conducted by Finch and Lavie in 2007, participants were given identical series of central cross-targets with two arms of clearly different color (blue and green) and slightly different length. Participants were split in two groups, one performing an easy task (low load condition) and the other a harder task (high load condition). The group performing the easiest task only had to make color discrimination between the tw...
The high percentages of individuals who endure this impairment justifies and practically demands future research because the causes are not fully understood. The need for future research can be better emphasized if those with normal vision try to empathize with victims of macular degeneration. One can only imagine how frustrating it must be to receive sensatrions only in the periphery of the retina. Because the macula encompassed the cone rich fovea, which is used to focus on objects, the fovea degenerates as well. This occurence inables individuals to interpret the sensations they experience. Reading, ...
While the Eighteenth Amendment, federally enforced prohibition, was ratified on January 16th, 1919; thirty three states had already been enforcing their own prohibitions for much longer. Prohibition was so widely accepted because of the awful effects it was having on the general populace. Throughout the history of the United States alcohol had a place in everyday life. It was not uncommon for it to be had at every meal, and there were even drinking breaks much like the smoke breaks we have in this day and age.(A Nation Of Drunkards. Prohibition: Roots of Prohibition. PBS, n.d. Web.) The staggering amount of alcohol abuse, mainly by men, wrecked havoc on the home lives many; either by lacking income as it was being spent on alcohol, or by domestic abuse. Temperance groups such as Women’s Christian Temperance Union; which fought for women’s rights as well as their dreams of a dry country, and the later Anti-Saloon League strived to get congress to pass an amendment that would abolish the manufacture, distribution, and sale of all liquor. The ASL grew in strength and became a particularly powerful social and political influence, and soon the amendment was ratified. The idea was noble, and for a just cause, however prohibition had the opposite effect than was anticipated. Rather than being the “The great social and economic experiment”(The New Day; Campaign Speeches of Herbert Hoover) that it was supposed to be, it increased crime rates and allowed for the formation of crime syndicates who would make millions in illegal liquor sales through, bootlegging; the illegal production of alcohol, and rum-running; the smuggling of liquor into the United States that was legally produced elsewhere.
It is a rare condition that affects 2 % of Americans. Signs of pathological myopia include: Bending or distortion of straight lines, altered color perception, reduced contrast sensitivity, and increasing gloss of central vision. It is a quick severe progression of myopia and loss of vision is the end result. There is an increased risk of retinal detachment and other degenerative changes in the back of the eye (bleeding from abnormal blood vessel growth). If any of these things occur the risk of cataracts could increase. Treatment calls for a combination of a drug and a laser procedure called photodynamic therapy. It is reported to be the seventh ranking cause of legal blindness in the United States of America the fourth ranking cause in Hong Kong and the second in parts of China and Japan this form of myopia frequently progresses in adult life, with small intermittent steps of elongation being observable at any age. The adult progression appears to be due to the stretching of the walls of the eye. Genetically weak elements of the scleral wall are prone to thinning and stretching. One of the major forces at work in this stretching process appears to be the normal intra-ocular pressure (Ward
Some believes that liquor prohibition was helpful with removing some of the America’s issues. That liquor was a huge drag on the economy. Also that drinking was behind America's most serious problems according to the background essay “Prohibition: Why Did America Change Its Mind?”. Drinking was behind serious issues such as corruption, child abuse, crime, unemployment and worker safety. That is not accurate mainly because during the prohibition, there was an enlargement of crime
Vecera, S.P. & Gilds, K.S. (1998) What Processing is Impaired in Apperceptive Agnosia: Evidence from Normal Subjects. Journal of Cognitive Neuroscience, 10 (5), p.568
His leadership inspired many to join his military, and he encouraged the clergy the build schools so the masses could learn how to read and write. Another thing he encouraged was the copying of Latin Manuscripts, so that old knowledge could be preserved. He also established a school in his palace, reserved for his children, and other nobles' children. But, due to many of his conquests, many people rebelled against him, though none had succeeded. This, in turn, lead to many massacres by the thousands, such as the one in Verden, when 4,500 rebellious Saxons were slaughtered on a single day. And because of his large empire, many other factions, even Abbasid Muslim nobles, pledged allegiance to him. In his time, Charlemagne's status as an Emperor gave him tremendous amounts of influence to almost everyone he ruled over. Overall, he was a feared and respected
In Miss Julie, August Strindberg depicts a tormented, sadomasochistic woman held captive by ingrained and inherent restrictions posed onto her by her aristocratic class. As she attempts to break free, her escapist tendencies cause various consequences to ensue, such as her eventual death. Other characters present also engage in the same escapist desires, especially present in Jean’s longing to advance his level in society. Such ideas end in disaster for any party involved. Strindberg manifests various character’s nonconformist ideas towards exaggerated barriers between social classes, such as those of Jean and Julie, to create themes on conformity and consequence.
Prohibition created a great deal of problems in America even though it was trying to correct one. Prohibition was not widely supported by many people. Prohibition led to many changes in our country. Some were bad and some were good. The effects on America were mostly bad. The good effects included no one could drink and it could try and contain the effects of being drunk. Prohibition also kept many people out of trouble with the law. Puritans believed that alcohol had a terrible effect on people and that is why they supported prohibition. Prohibition was the start of a “dry” era and led to many people staying sober and not drinking alcohol at all. This was a good effect on those people and their lives. They were more focused on their lives and tried to stay healthy, by not drinking. This was not true f...
...to encourage the church to reexamine a comfortable position in society and take the knowledge of the gospel beyond the upper and middle classes to evangelize among the poor. However, rather than assume the Church of England to carry evangelical religion to the people, he believed the people might perhaps evangelize themselves and ultimately transform the establishments of the church. Wesley wanted to "reform the nation and spread scriptural holiness over the land" (Church, 2014). John Wesley's great ally in this work was his brother Charles, whose influence on Methodism was chiefly in the hymns that he wrote for the new movement. Among populations with low rates of literacy and at a time when books were uncommon, the hymns of Charles Wesley became crucial instruments for the communication of religious ideas as well as a source of inspiration and communal solidarity.
Prohibition was enacted in order to fix serious problems in the United States, however prohibition failed to reduce crime, violence, and consumption. Not only did prohibition fail to do the above, it also hurt the economy. Prohibition is defined as “a ban on the production, transportation and sale of liquor” (The American Journey, 590). In 1920 congress approved the Eighteenth Amendment that made the sale and consumption of alcohol illegal. Even though estimates suggest that alcohol consumption was cut by over fifty percent, prohibition brought new problems to America. These problems include the rise of speakeasies, gangsters, and bootlegging. The intent of prohibition was to lower crime, poverty, family violence, prostitution, and industrial accidents. Overall prohibition failed at improving moral judgment and instead caused some major problems.
The images formed on the two retinas are so unlike that they cannot be blended in the brain. Thus, a double image is perceived. The condition is known as diplopia, or double vision. Prismatic lenses are prescribed to correct this defect.Imperfections in the cones of the retina, resulting from heredity or disease, cause defective color vision. This is known as color blindness, or Daltonism. In total color blindness, everything appears in shades of gray.