Show more. (96)Get rights and content P. Tougne, H. Hommel, A.P. Legrand, N. Herlin, M. Luce, M. Cauchetier. DOI: /(96) Cite this publication + 2. André Legrand at École Supérieure de Physique et de Chimie Industrielles. André Legrand. (Pease et al., ; Leon and Legrand, ). Human-. derived al., ; Léon and Legrand, ). Research Letters 32(3):L

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The Causes lefrand Prevention of Acquired Myopia. However, we are concerned primarily with human subjects, and it is important to demonstrate that the optical characteristics of animals are similar to Induced Refractive Errors in Human Subjects acuity.

This figure shows the positive A and negative B prints of the same scene at the top.

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The effect of restricted visual space on the refractive error of the young monkey eye. An apparatus for grading the visual acuity of infants on the basis of opticokinetic nystagmus.

I would like it. At very low light levels, the function describes the probability of arrival of photons, at each spatial position, within a test period. We will attempt simple definitions of these terms mainly by lgerand tration. It is an esotropia inward turn of one eye when the lateral rectus muscle is paralyzed, an exotro- pia outward turn when the medial rectus is paralyzed, and a hyper- tropia when one of the vertically acting muscles is paralyzed.

03066 studies on monkeys kept in the visually restricted space show no changes in refractive character- istics until a spasm of accommodation develops. It is generally thought that the use of cycloplegic drugs over such a period as several days to a week will induce the maximal degree of lenticular relaxation. It is not possible to introduce qualifying statements everywhere in this paper; the reader should accept values given as representative of typical subjects under optimal viewing conditions, unless otherwise stated.

Development of Optical Characteristics for Seeing lack of information are related to the difficulty of applying the methods outlined to neonates and very young children.

If he requires a plus or minus cylinder to correct astig- matism, he may be said to have hyperopic or myopic astigmatism.

Thus, he would have demonstrated a general ability to read and would be properly fitted with glasses to take care pegrand a visual deficiency. I think that this is ldgrand one of the main differences: In my review of early studies, I found reports that girls develop myopia earlier than boys, but girls read much more effectively than boys.


YOUNG Development of Optical Characteristics for Seeing Although it is not yet possible to describe completely the development of the optical characteristics of the human eye, it is possible, by relating results of published and unpublished studies with some amount of con- jecture, to put together a likely description.

It seems to me you are causing yourself a great deal of difficulty by trying to extrapolate movements of the eye from the stimulus pattern alone. He will be loath llegrand spend any time in reading, because he finds it distasteful. The in- fluence of the semicircular canals is, however, easily seen in the contra- versive displacement of the eyes in response to rotation of the head or irrigation of the ears with warm water conversely, cold water causes a deviation of the eyes to the side that it is applied to.

It may be related to congenital motor nystagmus, inasmuch as it occurs significantly often with this type. Figure 1, based on data from the original group, presents the propor- tion of persons requiring a minus lens for correction, by age groupings from 6 to 88 years of age.

The discussion has been in terms of similar errors in both eyes. Here and in experiments to be reviewed later, different conditions and experimental methods will inevitably yield different results. For practical purposes, the primary value of the Snellen acuity at either far or near distance would be to demonstrate whether a person has some type of visual refractive error large enough to prevent compensating for it through the use of accommodation, head tilt, squint- ing, or other techniques.

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It has been found that the symptoms of blur, dis- legranx, and headache become limiting factors in reading efficiency. What monkeys do and when they do it does not seem to be completely rele- vant to humans. A visual survey of Pullman school children.

The second reason for not appreciat- ing discontinuity is that, until the arrival of the computer age, the distinc- tions between “continuous” and “discontinuous” processes were not so concrete as they have been since we have begun to use these problem- solving machines, which are either analog continuous or digital discon- tinuous.


Finally, because of the nature of infor- A comparison of the optical characteristics of the human, ape, and monkey eye. Discharge patterns of single geniculate neurons during the rapid eye movements of sleep. I know of a number of cases in which clinicians have used bifocal lenses, which are virtually the same thing.

Estimation of the risk of transmission of hepatitis C between spouses in Egypt based on 03660 data. Romine9 thought that “it would seem most important to correct any marked degree of astigmatism,” and Cleland,5 sharing that view, stated that “in severe cases of astigmatism it was found to be closely allied with reading failure.

Much of the available legeand concerning the effects of heredity and environment on the development of the optical characteristics of the eye is based on studies of subhuman primates, primarily chimpanzees and monkeys. Furthermore, when 50 inside-cage animals were matched against 50 outside-pen animals on the basis of species, age, sex, weight, diet, legrwnd in captivity, and time spent in cage or pen, the caged animals were sig- nificantly more myopic than the outside-pen animals.

To fix an object to either side, the per- son turns his head instead of his eyes, but the contraversive deviation of the eyes necessitates an overshoot of the head for fixation.

J Virol Methods ; A developing eye that is characterized legrsnd a low intraocular pressure and a relatively high scleral rigidity may remain small in diameter even if the genetic component is directed toward greater size. How many hours did you allow the subjects taking the test? J Viral Hepat ;3: Let us consider some elementary facts about eye move- ments, overstating to some extent for simplification.

Eye Movements and Perception 1. In Pub- lic Health Bulletin Number Indeed, the results of even this simple experiment cannot be fully explained on the basis of our lgerand knowledge, although a general understanding is possible.

This article has been cited by 1 Meta-analysis Brittany E.