ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00679.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The theories and characteristics of anomalous retinal correspondence (ARC) are critically reviewed and a classification of ARC is proposed which attempts to reconcile various aspects of the different theories. It is suggested that ARC in microtropia, and perhaps some small‐angle squints, is a cortical adaptive mechanism, whereas squints with a larger and more variable angle have ARC with different characteristics, which are better explained by the motor the

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00680.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—A stabilized image of a coloured square seen against a black background was produced. After the image had faded, oscillatory movements were applied in a direction parallel to a diagonal so that all boundaries had an equal component of motion normal to themselves. Movements of different frequency, amplitude and wave‐form were studied. Most of the experiments were carried out at fairly high retinal illuminance (80–500 td). The objective was to find the amplitude and frequency required for perception of hue and saturation. It was found that these movements had (i) a minimum amplitude of about 5′ (10′ peak‐to‐peak), (ii) a minimum velocity of 15′‐1and (iii) a frequency range from about 1 Hz to about 4 Hz. The movements required are larger than those required for perception of the shape of the target and also larger than the normal movements which remain when a subject fixates a well‐defined mark. Also the movements associated with the perception of hue and saturation are restricted to a narrower frequency range. These features probably imply that it is necessary to excite numbers of cones covering a minimum area to give perception of

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00681.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The effect upon the detectability of broad bars and a sharp edge of ideal low‐and high‐pass filters was investigated. The results indicate that, for optimum detection of the stimulus, spatial frequency components up to about 5 c deg‐1need to be transmitted. Two models (a multi‐channel model, incorporating probability summation across spatial frequency, and a Grating Sensitivity Curve model) were used in attempting to fit the results. The multi‐channel model provided a more realistic fit, but both models ultimately failed because of non‐linearity in the summation of responses to frequen

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00682.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The validity and efficacy of the prognosis equation published by Saunders (1984b) is tested against previously reported longitudinal data. In a fair and random sample and over a short interval, nearly 60% of the sample was found to have a prediction error of less than 0.25 DS and, in 92%, the error involved was less than 0.5 DS. Long‐term prediction was found to have a less favourable outcome but 50% were correct within an error of 0.5 DS and 90% were found to have a prediction error of less than 1 DS. The largest prediction errors occur in the medium to high myopes whose myopia progresses rapi

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00683.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The analysis by Helmholtz (1910) of the geometry of binocular vision has been modified to allow computerized calculation of specific examples of horopters. These are used to clarify the relationship between the shapes of the horopters and the physiological constraints involve

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00684.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The effects that lateral prisms have on the horopter were evaluated in 11 subjects, including 6 subjects classified as binocularly abnormal. For normal subjects with good stereopsis the equidistance (stereoscopic distance matching) horopter shape was altered with the application of lateral prism. For other subjects this was not the case. Equidirection (nonius) horopters were unchanged by the application of lateral prism in all of the subjects tested. In addition to localized irregularities in the horopter locus, shifts in fixation disparity produced regional distortions of the horopte

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00685.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—There exists some controversy regarding the effects of active horizontal head rotation on vergence error. We used a conventional, Ogle‐type, subjective fixation disparity apparatus to measure vergence error at near over a full range of horizontal head‐rotation frequencies. Change in vergence error rarely exceeded 10 min arc. This finding demonstrates the adequacy of the vergence system to maintain relatively accurate bifixation at near and to allow for continuous maintenance of binocular sensorymotor integrative ability, even in the presence of system perturba

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00686.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—The binocular contrast sensitivity function is measured using horizontal sinusoidal gratings with base‐down prism before the right eye. In photopic conditions one prism‐dioptre causes a significant drop in sensitivity at all spatial frequencies and in mesopic conditions as little as a half prism‐dioptre has a similar effect. The implications for a physiological tolerance for unintended vertical differential prism in spectacles are di

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00687.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Abstract—Orthoptic therapy was instituted in an adult, alternating esotrope with asthenopia who exhibited inaccurate static accommodative responses with adequate, clinically determined, accommodative facility. During and following therapy the patient showed considerable improvement in accommodative accuracy and related visual functions, such as contrast sensitivity, in the absence of any change in strabismic deviation. This case provides the first laboratory documentation of orthoptic effects on accommodation in an adult strabismi

ISSN:0275-5408    

DOI:10.1111/j.1475-1313.1985.tb00688.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY