Visual Perception Deficit: Cataract and Glaucoma

In: Science

Submitted By raelenecerise25
Words 10994
Pages 44
Liceo de Cagayn university – graduate studies | Visual Perception Deficits | Cataract & Glaucoma | Submitted by: | Nadine Angelica C. Gadia – Casiño, RN | March 18, 2012Submitted to:Ms. Delia V. Realista, RN, MANProfessor |


I. Intoduction
Cataracts are common and significant cause of visual defects all over the world. A cataract is an opacification or clouding of the lens of the eye. Cataracts develop because of the alteration of transport of nutrients and metabolism in the lens. This interferes with light transmission to the retina therefore affecting the ability to perceive images clearly. All cells of the lens formed in the lifetime is retained therefore prevalence of cataracts increase rapidly with aging.
WHO estimates that cataracts account for 48% of reversible blindness worldwide, which translates to about 18 million people. Cataracts affect slightly more women than men. The Beaver Dam Eye Study in the US found that 23.5% of women and 14.3% of men had a visually significant cataract by the age of 65 years. Although cataracts can be surgically removed, in many countries surgical services are inadequate, and cataract remains the leading cause of blindness.
Age is the greatest risk factor in the occurrence of cataracts. Cataract, though with unclear links, may be acquired through heredity and genetics (e.g., Wilson's disease, galactosaemia, myotonic dystrophy). Early formation of cataracts is associated with the following risk factors: * Environmental and lifestyle factors such as long term exposure to glares (e.g. welding) and sunlight, smoking and heavy alcohol consumption * Diabetes mellitus particularly in patients with poor control of blood glucose. * Long-term use of corticosteroids
With the clouding of the lens light rays scatter as they pass through thus decreasing visual acuity. There are complaints…...

Similar Documents

Deficit and Surplus

...Why the U.S.’s deficit, surplus and debt have an effect on a domestic automotive manufacturing (exporter) and The United State’s financial reputation on an international level The United States financial reputation on an international level The new economic cycle; 2000 to 2001 the United States economy has gradually dropped. This dropped occurred before September 11, 2001 terror attack and continued during the international financial crisis. The United States is struggling with the fundamental or comprehensive which has hinder the strength of the United States. One major problem is the fiscal and trade deficits. "In 2010, the fiscal deficit in the United States was $1.3 trillion or approximately 9 percent of U.S. GDP" (The Brookings Institution.) The budget deficit and debt limit the resources to spend on production and investment. Similarly, the impact of imported products on employment in the United States is not as much as great as some sensational arguments might make it appear. This is because most products imported by the United States are not produced by the United States, or are produced by the United States in a quite small amount. A domestic automotive manufacturing (exporter) The U.S. current account goods and services trade deficit which is balanced by our foreign investment surplus. Trade just means exchanging in which when we export fewer foreigners then they export to us. In all actually The U.S. could be getting compensate for that. By exporting less......

Words: 466 - Pages: 2


...Cataract Definition: Opacity of the lens that distorts the image projected on to the retina and which can progress to blindness. Types of cataracts include: * * Senile * Congenital * Traumatic * Secondary Anatomy and Physiology: * Cornea - It is the outermost lens of the eye, controlling and focusing incoming light. It shields the rest of the eye from dust, germs and other harmful foreign matter. * Sclera - The visible white part of the eye.The sclera is a protective layer that maintains the global shape of the eye and offers resistance to internal and external forces. * Iris - The part of the eye which is colored. The iris is a diaphragm that regulates the expansion and contraction of the pupil to allow in the required amount of light. * Choroid – contains blood vessels and supplies nutrients to the retina. * Ciliary Body - Connects the choroids with the iris and secretes aqueous humor that helps the eye its shape. * Retina - The retina is the link between the brain and the light entering the eye. The retina is a complex structure able to convert the impacting light into nerve impulses that are then sent to the brain along the optic nerve.  * Rods are photoreceptors responsible for peripheral vision and function at reduced levels of illumination. * Cones function at bright levels of illumination and are responsible for color vision and central vision. * Vitreous body – transmits light and gives shape to......

Words: 1638 - Pages: 7


...------------------------------------------------- Top of Form Search Options Bottom of Form * Home * Contact Us * Access old SpringerLink Sign up / Log in   English   Academic edition Attention, Perception, & Psychophysics© Psychonomic Society, Inc. 201210.3758/s13414-012-0370-4 Contextual influences of dimension, speed, and direction of motion on subjective time perception Spencer R. Kline1 and Catherine L. Reed1   (1) Department of Psychology, Claremont McKenna College, 850 Columbia Avenue, Claremont, CA 81711, USA     Catherine L. Reed Email: Published online: 14 September 2012 Abstract Research has indicated that the direction of motion and the speed of motion can influence the subjective estimates of temporal duration of two-dimensional (2-D) stimuli expanding and contracting within the picture plane. In this study, we investigated whether the contextual cues of stimulus/movement-plane dimensionality (2-D stimuli with implied movement in the picture plane or depth-rendered “3-D” stimuli with implied movement in the depth plane) influence and interact with speed and implied movement direction during interval estimation. Participants viewed a series of standard stimulus durations followed by a test stimulus duration and determined whether the test and standard durations differed. The results indicated that moving stimuli were overestimated relative to stationary stimuli, regardless of the direction of motion or......

Words: 5263 - Pages: 22


...they have a profit sharing relationship. The following are the findings of my investigation that checks the extent of damage; by using a cause effect relationship and my proposal of what short-term actions can be taken to minimize its repercussions. Challenges Identified In this case I have used a fish bone diagram to analyse the review and its broad results are as given below: * There was a mismatch of perception and expectation, both, which were reviewers, through posters and spot-checking with the staff. It reflects the poor co-ordination of the marketing department and operations. * Lack of entrepreneurial competence and commitment * Inability to establish and formalize operational standards * Lack of training, direction and motivation in the kitchen and of service staff * Frequent critical incidents * Inability to match ‘experience’ to basic concept * Failure in constant innovation. * Inability to customize guest needs * Lack of organizational culture fostering success characteristics * Negative consumer perception of value * Mediocre wine list which has not recognised the country’s growing wine maturity * The final product is not at par with the original recipe of Marcus Vesty * The Abbey is losing its market position from 2nd highest revenue generator in 2009 to 4th in 2011 * Underestimating competition * Absence of benchmarking across the business * Changing demographics trends * Failure to......

Words: 1278 - Pages: 6

Sensorineural Disorder: Glaucoma

...Nursing 2249 Sensorineural Disorder: Glaucoma Blindness is defined as the loss of usual site. One of the leading causes of blindness is Glaucoma. In ancient Greek, glaucoma meant “clouded” or a blue-green hue. It is now defined as a “progressive” optic neuropathy with characteristic structures in the optic nerve head and functual changes in the visual field. If left untreated irreversible blindness is inevitable. Increased ocular pressure is a function of the production of aqueous humor by the ciliary processes of the eye. This fluid flows through the pupil of the iris into the anterior chamber. Eventually, the iris is pushed forward against the trabecular meshwork, blocking fluid from escaping. The clinical manifestations include: gradual vision deterioration, peripheral vision deterioration, blurred vision, sensitivity to light, halos around bright lights, mild eye pain, nausea and headaches to name a few. The client interviewed reported that this disease lead to his blindness and he adapted to his new way of life by beginning a web page. He is also learned the Braille system and has voice activated response on a home computer that allows him to communicate and continue with his life. Although glaucoma can affect any race, African Americans over 40 and people with a family history are more susceptible. Similarly, some Asians have narrower anterior chambers and are far more prone to acute glaucoma at a young age. The......

Words: 332 - Pages: 2


...Michael Ignatieff's essay "Deficits" is a personal essay that gives a reader deep insight into the thoughts and emotions of a man as he witnesses his mother degrade. I think that is what that is about. So the thing is, I really just kind of want to gain access to this site and why would I want to write an essay for that? I am not entirely sure and so I am writing this document in order to see if it will work. This will be entertaining if someone reads it or something. Anyway, guess what? There are absolutely no membership fees at Well that is simply incredible. Insane. Extraterrestrial. You're so hypnotising. Thank goodness it's Friday, people. Thank goodness. Oh wait, it's not even Friday. I have become sad. Now I am going to give you some tips for formatting a paper in MLA format. To my understanding, you should start by writing a sequence of four lines in the top left corner with your name, your teacher or professor's name, the course name, and the date. The title should be centered and the essay should follow, double spaced, with indents at the start of each new paragraph, of course! You should also number the pages, each number preceded by your last name. Do not create a title page unless one is specifically asked for. Hopefully that is correct information, so that this essay can be at least a little bit helpful. I am not even really sure what this website is. However, I am simply thrilled to hopefully find out soon. Furthermore, I sometimes find......

Words: 382 - Pages: 2

Visual Perception and the Pop-Out Effect

...Cognitive Neuropsychology (psy2010s) | Visual Perception and the Pop-out Effect | Tutorial 1 Assignment | | Zondi Londiwe (ZNDLON002) | 8/30/2013 | | INTRODUCTION Visual information is constantly presented to humans by the environment, and at times this can be far more than can be processed or needed. It is visual attention that allows the most relevant information for behaviour adjustment to be selected. Searching for particular objects that determine our actions whilst ignoring other competing objects can take long, especially if the objects all share common features. A number of theories that explain the process of visual search have been presented throughout the years. However the most common is the Feature Integration Theory developed by Treisman & Gelade (1980). According to The feature integration theory, visual search happens in a two-stage process, the pre-attentive stage and the attentive stage. The pre-attentive stage is the basic stage of visual search where only basic features, such as the size, colour and orientation, of an object are processed (Treisman, 1988; Treisman & Galade, 1980). At this stage no focused attention is required because all the objects in the visual stimulus are processed in parallel. The second stage requires more attention as the search becomes serial i.e. each object is processed independently ((Treisman & Gelade, 1980). Also, parallel searching takes less time than serial searching. Parallel and serial......

Words: 2369 - Pages: 10


...PERCEPTION 1. We all see the world in our own way, and interpret it differently. Several people can see the same incident and give very different accounts. 2. Senses differ from perception 3. For marketers, consumers perceptions are much more important than their knowledge of objective reality. "Reality" is an individuals perception of what has taken place. 4. What people think or believe is in many ways more important than what really is 5. Perception is defined as "how we see the world around us" our perception is based on our needs, values, expectations 6. Perception is the process by which an individual selects, organises and interprets stimuli into a meaningful and coherent picture of the world (stimulus = input to the senses). 7. Sensation = immediate and direct response of the sensory organs to simple stimuli eg. an advertisement, a brand name, a package. 8. ABSOLUTE THRESHOLD = point at which a person can detect a difference between something and nothing. It is different for each individual - adaptation = getting used to a sensation senses becoming dulled to it, because of adaptation, advertisers try to change their campaign regularly, use attention gaining techniques eg. samples, stunts etc. Packaging also is designed to stand out from the rest, to gain attention. i.e. if you sense the same thing over and over again you will become bored with it and turn off from it. 9. DIFFERENTIAL THRESHOLD = minimal difference between two......

Words: 1105 - Pages: 5


... A cataract is a cloudiness of the lens in your eye that prevents light from being focused clearly on the retina, which can impair your vision.  There are three different types of cataracts. -Nuclear -Subcapsular -Cortical A nuclear cataract forms deep in the central zone (nucleus) of the lens. Nuclear cataracts usually are associated with aging. A subcapsular cataract occurs at the back of the lens. People with diabetes have a greater risk of developing a subcapsular cataract. A cortical cataract is characterized by white, wedge-like opacities that start in the periphery of the lens and work their way to the center in a spoke-like fashion. This type of cataract occurs in the lens cortex, which is the part of the lens that surrounds the central nucleus.  Cloudy or blurry vision.  Colors seem faded.  Poor night vision.  Double vision or multiple images in one eye.  Frequent prescription changes in your eyeglasses or contact lenses. Normal Vision Vision with cataracts  Macular Degeneration--loss of central vision due to damage to the macula and surrounding blood vessels.  Retinal Detachment--Medical Emergency. Loss of vision can result if not treated within 24 hours of onset of symptoms.  Glaucoma--Fluid gets trapped in the eye causing an increase in eye pressure.  Diabetic Retinopathy--damage to the blood vessels in the retina caused by Diabetes A cataract only needs to be removed when vision loss interferes with......

Words: 328 - Pages: 2


...|Cas Visual | | | |[Tapez le sous-titre du document] | | | |[Sélectionnez la date] | | | |Romain | | |[Année] | Cadre de reference fondamental Vocation : Statut Visual est une coopérative depuis 40 ans , ce qui implique que pour les prises de décisions elle repose sur le principe démocratique "1 personne = 1 voix". Les membres-usagers et les salariés sont donc tous égaux en droit. Une enseigne Visual a alors une plus grand liberté de monoeuvre car dans l'ensemble "tout est proposé, très peu de choses sont imposée". Par exemple il n'y a pas de sanctions si toutes les règle d'appartenance établit par la coopérative ne sont pas appliquées (expeté les retard de payement). Avoir une enseigne donne l'accès à tous les services du groupe gratuitement. Le metier Visual regroupe des......

Words: 4519 - Pages: 19

Trade Deficit

...OF CONTEMPORARY RESEARCH IN BUSINESS EFFECT OF TRADE DEFICIT ON THE ECONOMY OF PAKISTAN Mohsin Abbas Superior University, Lahore, Pakistan Hassan Raza (Corresponding author) University of Lahore, Lahore, Pakistan Abstract This study has conducted to find the effects of trade deficit on the economy of Pakistan in which trade deficit is the independent and gross domestic product, foreign direct investment exchange rate are the dependent variables. Depending on the availability of data we have selected the longest possible sample period to avoid the small sample bias. A sample period of 24 years has been selected for this study for the period of 1988-2011 with annual frequency. We use histogram, scatter plot matrix and the correlations ordinary least square method of regression has been used for the analysis.Histogramof exchange rate show rupees value against U.S dollar are continuously decrease. FDI is also not good, Gross domestic product (GDP) of the Pakistan is also very low trade,In histogram also represent the trade volume (TV) in which imports of Pakistan is very high while export is low. Scatter plot show the positive relationship dependent and independent variables except trade volume. So its result shows if the government working on these variables then trade deficit should automatically decrease like 2003 and 2004 in which our export are more as compare to import .correlation coefficient of trade deficit with gross domestic product, foreign direct investment,......

Words: 14436 - Pages: 58


...(12 marks). b) Assess the way in which such studies help to explain the development of perception (12 marks). In the following essay I intend to describe two studies of perceptual development. I then intend to assess such studies and how they help to explain the development of perception. By perceptual development, I mean how animals and humans alike develop their seeing capabilities. This development of perception could be learnt or innate. By innate, I mean to be born with the ability. a) Gibson and Walk conducted a study in 1960. The study was investigating Depth Perception. The study involved a 6-month-old child, 24-hour-old chicks, kids and lambs. Gibson and Walk used a 'Visual Cliff' to conduct the study. The 'Visual Cliff' was comprised of 2 floors. On one side there was a check-board pattern, on the other side there is glass floor. Below the glass floor there was another floor with check-board pattern. This was placed so that an illusion of a cliff and depth was created. At first the child was placed and was found to be reluctant to go onto the glass. The child's reluctance could be seen as even with encouragement from the child's mother, the child refused to go onto the glass. The study was continued on chicks, kids and lambs. All subjects studied refused to go onto the glass. Held and Hein conducted a study in 1965. The study was investigating Depth Perception. The study involved two kittens. The kittens were kept in the dark for a period......

Words: 370 - Pages: 2

Deficit Spending

..."Deficit Spending Introduction Deficit spending has become one of the highly discussed concepts in the corporate market. Deficit spending refers to the amount by which the spending of an organization exceeds the revenues in a particular period of time (William and Alan, 2005). The term can also be applied to the budget of an individual, family or government. The term can also be used to refer situations like imports exceed exports and liabilities exceed assets. Taking a loan that has to be repaid after certain period of time, say two years, at low interest rate to use the money on important things can be considered as an example for deficit spending (Oxley & Martin, 1991). If the loan taken by the individual right now is more important than the interest money that he or she spends on interest, it can be considered as a good deficit spending deal and vice versa. The deficit spending can be explained by referring to the activities of Federal Government. When then expenditure exceeds its revenues, the government will try to borrow, likely from foreign governments, to finance the excess spending needs (William and Alan, 2005). Governments will operate in deficit spending with the anticipation that the increased government spending will stimulate economic growth. Advantages of...

Words: 1001 - Pages: 5


...Deficits by Michael Ignatieff It begins the minute Dad leaves the house. “How is George?” “He is out now, but he’ll be back soon.” “That’s wonderful,” she says. About three minutes later, she’ll look puzzled: “But George…” “He’s away at work, but he’ll be back later.” “I see.” “And what are you doing here? I mean it’s nice, but…” “We’ll do things together.” “I see.” Sometimes I try to count the number of times she asks me these questions but I lose track. I remember how it began, five or six years ago. She was 66 then. She would leave a pot to boil on the stove. I would discover it and find her tearing through the house, muttering, “My glasses, my glasses, where the hell are my glasses?” I took her to buy a chain so that she could wear her glasses around her neck. She hated it because her mother used to wear her glasses on a chain. As we drove home, she shook her fist at the windscreen. “I swore I’d never wear one of these damned things.” I date the beginning to the purchase of the chain, to the silence that descended over her as I drove her home from the store. The deficits, as the neurologists call them, are localized. She can tell you what it felt like when the Model T Ford ran over her at the school gates when she was a girl of seven. She can tell you what a good-looking man her grandfather was. She can tell you what her grandmother used to say, “A genteel sufficiency will suffice,” when turning......

Words: 2461 - Pages: 10

Visual Impairment

...Visual Impairment Introduction Vision challenge or impairment is when a person’s degree of seeing is very low and the affected person requires assistance in order to carry out daily routine. Significantly, for one to qualify as visually impaired there must be prove that a person cannot undertake duties by himself without necessary assistance. For a person to qualify as a visually challenged, there must be a prove that the affected eyes cannot be conventionally treated. Visual challenge cannot be corrected by surgery, refractive measures neither by medication and that is why it is termed as visual impairment. The most rampart causes of visual challenge are trauma, degenerative or congenital means and a variety of diseases. In the society, blindness is the term that is preferably used to describe a visually impaired per son. Low eyesight is generally revealed when the affected person cannot view a normal distance and walk by himself (Algozzine, 2006). The degree of impairment can also be revealed when a person cannot read some normal writings. This is to say that even with the assistance of contact magnifying glasses or even eyeglasses the victim cannot reveal the writings on a normal newspaper (Bailey & Hall, 1990). Hyperopic impairment is accrued with inability person to see objects in a close distance. Myopic impairment is quite the opposite of hyperopic whereby a victim cannot identify objects at close distance. All these vision challenges greatly obscure the affected......

Words: 3395 - Pages: 14

Seikoku no Dragonar | Wondershare Data Recovery | Return Of Wolverine #3C (1:50) Zircher Variant (Wk48)