ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Editors Note On December 13, 1973 at the Annual Meeting of the American Academy of Optometry in San Francisco, Drs. Hirsch and Morgan interviewed Dr. Policoff. Videorecording of the 1-hr interview was directed by Robert Tarr from the University of California School of Optometry Multi-media Center. Portions of the original recording were later duplicated to create a 20-min version which was shown at the Policoff Symposium and from which the following complete text and selected pictures were taken.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Four forms of nerve terminals in extrinsic eye muscles are described: the Golgi tendon organ, the palisade sensory ending, the palisade motor ending, and the spiral ending. Sensory and motor functions are assigned to these endings based on morphological criteria.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Visual acuity (minimum target size for threshold visibility) was measured as a function of luminance, contrast, and distance in experiments using 16 partially sighted persons. The results indicate large individual differences in dependence of visual acuity on both luminance and contrast. Visual acuity often failed to change systematically with variations in the testing distance; the effects of contrast and luminance on visual acuity also frequently failed to show any systematic dependence on viewing distance. The relation of acuity in the partially sighted to medical diagnosis is discussed along with some practical implications.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

Forty-nine subjects (ages 8–55) were tested with the circles and animals of the Titmus Stereo test while wearing Polaroid(tm) filters at axis 135 deg before both eyes so that the right eye's target was presented to both eyes. This procedure removed retinal image disparity as a cue to depth and left lateral displacement as the primary cue to obtain correct responses on the test. The subjects' scores on the circle test were much higher than expected by chance guessing. Different instructions to the subjects did not influence this result. Scores on the animal test were similar to those expected by chance. The subjects used lateral displacement as a response cue on the circle test but not on the animal test. Procedures for improving the validity of the Titmus Stereo test are described.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

The literature related to the effects on the eye of ultraviolet radiation in the wavelength range 300 to 400 nm is reviewed. Insufficient data are available to establish criteria for ocular protection. Exposure of the eye to sufficient quantities of near ultraviolet radiation can interfere with synthesis of crystalline lens protein, catalyze lens proteins, produce chromatic changes in the lens, and enhance formation of cataract.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

When the eyes fixate a point in the median plane of the head, the physical surface to which the stereoscopic disparities of “nearer” and “farther” points are referred is the so-called frontal plane horopter. When, however, a point is fixated with the eyes in asymmetrical convergence, the horopter is now rotated with respect to the objective normal plane-that is, the surface that is normal to the direction of gaze. This rotation is believed to pose a problem with veridical stereoscopic localization. It has, therefore, been postulated that in asymmetrical convergence some physiological compensation takes place in order to preserve accurate stereoscopic perception. Some experimental evidence apparently supports this view. The logic of the arguments and the experiments are critically assessed with the conclusion that there is little evidence of any visual modification, nor would any seem likely. A reinterpretation of the stereoscopic axes of reference does occur, but this can be accounted for purely by innervational factors, the visual aspects remaining unchanged.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

The magnitude of fixation disparity has been proposed to be uncorrelated with stereoscopic sensitivity. Studies on this relationship have been confined to the effects of vergence-induced fixation disparity on stereoacuity: some subjects exhibited decreased stereoacuity with induced fixation disparity. The present study was designed to determine whether prismatic correction of naturally occurring horizontal fixation disparity would result in increased stereoacuity. Five subjects with eso and 5 with exo fixation disparity had their fixation disparity curves and stereothresholds evaluated before and after wearing corrective lenses and prisms that neutralized the fixation disparity. Five subjects with no fixation disparity served as controls. After 1 month most subjects showed no change in their fixation disparity curves and stereothresholds.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID

摘要:

A method of color naming was used to determine the spectral locus for unique green (UG) as it was perceived by 20 color normals and 24 deuteranomalous trichromats. The loci for the normal group were distributed bimodally, as earlier investigators had reported, and a bimodal distribution was also found for the deuteranomalous group. In the latter group, UG was located at long wavelengths only by those who had been classified as mild deuteranomals according to several clinical criteria. Those who located UG at shorter wavelengths included individuals whose defects ranged from mild to severe. This result is discussed in the context of theories of deuteranomaly and is presented as further evidence for the existence of 2 types of deuteranomaly.

ISSN:0093-7002    

出版商:OVID    

年代:1977

数据来源: OVID