PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Vision, Monocular”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources
PubMed1988

Oculomotor disturbances and VER findings in patients with early monocular loss of vision.

Visually evoked potentials (VER) were studied in 16 patients over 3 months of age with congenital or very early loss of vision in one eye. Seven patients (group I) developed an oculomotor syndrome in the sound eye characterized by jerky nystagmus in abduction, adduction fixation preference, and head-turn toward the side of the fixating eye. The other nine patients (group II) failed to develop the above-described syndrome. In group I, VER response asymmetry was found in six cases, with crossed predominance in four and direct predominance in two. The 7th patient showed a symmetric response. In group II, eight of the nine patients showed symmetric VER responses, and one showed asymmetric response with crossed predominance. Recorded VER asymmetries seem to correlate with oculomotor disturbances.

Adolescent↗
PubMed1982

Binocular deprivation can erase the effects of preceding monocular or binocular vision in kitten cortex.

Kittens were given visual experience through one or both eyes for two weeks around the peak of the sensitive period. Subsequently they were binocularly deprived for at least one year. This period of pattern deprivation erased completely the effects of the preceding temporary experience. Ocular dominance distribution, orientation selectivity and response quality of the cortical units resembled those obtained from kittens which are contour-deprived throughout their early postnatal development. This suggests that the effect of visual experience is not to engrave irreversibly certain features of the early visual world, but to adapt the cortex continuously and in an integrative fashion to features which are prominent throughout the sensitive period.

Animals↗
PubMed2005

Video-assisted surgery represents more than a loss of three-dimensional vision.

BACKGROUND: Loss of depth cues is a major challenge facing surgeons performing video-assisted surgery (VAS). Whether the degradation of image quality from a video-displayed image plays a direct role in performance of VAS has not been studied. METHODS: Twenty-four volunteer novice subjects were randomized to binocular direct-vision (BDV), monocular direct-vision (MDV), or video-imaging (VI) conditions. Each subject completed ten trials of a simple cutting task in a box trainer using standard laparoscopic instruments. RESULTS: VI subjects made significantly fewer correct incisions than both of the other groups for all trials. Differences between the BDV and MDV groups did not reach statistical significance. Improvement in performance was more rapid in the BDV group than in either the MDV or VI groups. CONCLUSIONS: The degradation of image quality with VI has a detrimental influence on VAS performance above and beyond the loss of binocular vision.

Adult↗
PubMed2005

Perceptual compensation for eye torsion.

To correctly perceive visual directions relative to the head, one needs to compensate for the eye's orientation in the head. In this study we focus on compensation for the eye's torsion regarding objects that contain the line of sight and objects that do not pass through the fixation point. Subjects judged the location of flashed probe points relative to their binocular plane of regard, the mid-sagittal or the transverse plane of the head, while fixating straight ahead, right upward, or right downward at 30 cm distance, to evoke eye torsion according to Listing's law. In addition, we investigated the effects of head-tilt and monocular versus binocular viewing. Flashed probe points were correctly localized in the plane of regard irrespective of eccentric viewing, head-tilt, and monocular or binocular vision in nearly all subjects and conditions. Thus, eye torsion that varied by +/-9 degrees across these different conditions was in general compensated for. However, the position of probes relative to the midsagittal or the transverse plane, both true head-fixed planes, was misjudged. We conclude that judgment of the orientation of the plane of regard, a plane that contains the line of sight, is veridical, indicating accurate compensation for actual eye torsion. However, when judgment has to be made of a head-fixed plane that is offset with respect to the line of sight, eye torsion that accompanies that eye orientation appears not to be taken into account correctly.

Eye Movements↗
PubMed1992

Prevalence of disabled stereopsis in a class of optometry students.

Stereopsis is said to be disabled when the third dimension (3-D) cannot be perceived during everyday life but can be when viewing conditions are appropriately arranged. To discover a test suitable for detecting disabled stereopsis, I measured stereoacuity, stereolatency, and the subjective difference in depth perception between monocular and binocular vision of a group of 41 optometry students. Only 2 students showed no sign of this disability. A predictive value for each test was calculated from the results of 14 students whose disability was confirmed by another means. Stereoacuity had the worst predictive value (43%) and stereolatency the best (100%). The prevalence of disabled stereopsis in this group was no less than 34% and might have been as great as 95%.

Depth Perception↗
PubMed1988

Japanese monkeys' cardiac responses to visual depth.

The present study examined the heart-rate changes which occurred in the visual-depth situation of Japanese monkeys (Macaca fuscata). Four animals were tested over the first four weeks of age in the visual pitfall designed as a modification of the visual cliff. The infant monkeys showed heart-rate reduction in the depth condition. This reduction was observed from the first week and became remarkable at the third week. There were no differences in heart-rate change between monocular and binocular vision. These findings suggest that the Japanese monkey can discriminate visual depth shortly after birth and that the heart-rate reduction depends upon the fear of visual depth, not upon the novelty of the situation.

Animals↗