UNASSIGNED: Do one-eyed (uniocular) humans use monocular depth cues differently from those with intact binocularity to perform depth-related visuomotor tasks that emulate complex activities of daily living? If so, does performance depend on the participant\'s age, duration of uniocularity and head movements?
UNASSIGNED: Forty-five uniocular cases (age range 6-37 years; 2.4 months-31.0 years of uniocularity) and 46 age-similar binocular controls performed a task that required them to pass a hoop around an electrified wire convoluted in depth multiple times, while avoiding contact as indicated by auditory feedback. The task was performed with and without head restraint, in random order. The error rate and speed were calculated from the frequency of contact between the hoop and wire and the total task duration (adjusting for error time), respectively, all determined from video recordings of the task. Head movements were analyzed from the videos using face-tracking software.
UNASSIGNED: Error rate decreased with age (P < 0.001) until the late teen years while speed revealed no such trend. Across all ages, the error rate increased and speed decreased in the absence of binocularity (P < 0.001). There was no additional error reduction with duration of uniocularity (P = 0.16). Head movements provided no advantage to task performance, despite generating parallax disparities comparable to binocular viewing.
UNASSIGNED: Performance in a dynamic, depth-related visuomotor task is reduced in the absence of binocular viewing, independent of age-related performance level. This study finds no evidence for a prolonged experience with monocular depth cues being advantageous for such tasks over transient loss of binocularity.

Sports performance is relatively robust under high levels of binocular blur. However, the limited research studies investigating monocular impairments has shown it has a larger impact on sport performance. This research study is relevant for classification in sports for athletes with vision impairment (VI), where visual acuity (VA) from the better eye is used during classification. Across two experiments, we aimed to establish the point at which binocular and monocular impairments affected performance in a football penalty kick (PK) through simulating varying severities of degraded VA and contrast sensitivity (CS) in active football players. In experiment one, 25 footballers performed PKs as VA and CS were systematically decreased in both eyes, and in one condition, visual field (VF) was reduced. The most severe VA/CS condition and reduced VF significantly impacted outcome, ball velocity and placement (ball kicked closer to the centre of the goal) (p < 0.05). In experiment two, 29 different footballers performed PKs as VA and CS of only the dominant eye were systematically decreased and in one condition the dominant eye was occluded, and participants viewed their environment through the non-dominant eye (monocular viewing). No differences were observed when assessing monocular impairments influence on outcome, velocity and ball placement. PKs have a high resilience to VI, but binocular impairment has a more immediate effect, suggesting binocular measures should be used in classification processes in football.

Image differences between the eyes can cause interocular discrepancies in the speed of visual processing. Millisecond-scale differences in visual processing speed can cause dramatic misperceptions of the depth and three-dimensional direction of moving objects. Here, we develop a monocular and binocular continuous target-tracking psychophysics paradigm that can quantify such tiny differences in visual processing speed. Human observers continuously tracked a target undergoing Brownian motion with a range of luminance levels in each eye. Suitable analyses recover the time course of the visuomotor response in each condition, the dependence of visual processing speed on luminance level, and the temporal evolution of processing differences between the eyes. Importantly, using a direct within-observer comparison, we show that continuous target-tracking and traditional forced-choice psychophysical methods provide estimates of interocular delays that agree on average to within a fraction of a millisecond. Thus, visual processing delays are preserved in the movement dynamics of the hand. Finally, we show analytically, and partially confirm experimentally, that differences between the temporal impulse response functions in the two eyes predict how lateral target motion causes misperceptions of motion in depth and associated tracking responses. Because continuous target tracking can accurately recover millisecond-scale differences in visual processing speed and has multiple advantages over traditional psychophysics, it should facilitate the study of temporal processing in the future.

Binocular visual plasticity can be initiated via either bottom-up or top-down mechanisms, but it is unknown if these two forms of adult plasticity can be independently combined. In seven participants with normal binocular vision, sensory eye dominance was assessed using a binocular rivalry task, before and after a period of monocular deprivation and with and without selective attention directed towards one eye. On each trial, participants reported the dominant monocular target and the inter-ocular contrast difference between the stimuli was systematically altered to obtain estimates of ocular dominance. We found that both monocular light- and pattern-deprivation shifted dominance in favour of the deprived eye. However, this shift was completely counteracted if the non-deprived eye\'s stimulus was selectively attended. These results reveal that shifts in ocular dominance, driven by bottom-up and top-down selection, appear to act independently to regulate the relative contrast gain between the two eyes.

OBJECTIVE: To assess the impact of glaucoma on perceiving three-dimensional (3D) shapes based on monocular depth cues.
METHODS: Clinical observational study.
METHODS: Twenty glaucoma patients, subjected to binocular visual-field sensitivity (binocular-VFS) tests using a Humphrey Visual Field Analyzer, and 20 age-matched healthy volunteers, underwent two tasks: identifying the nearest vertex of a 3D shape using monocular shading (3D-SfS), texture (3D-SfT), or motion (3D-SfM) cues, and distinguishing elementary one-dimensional (1D) features of these cues. The association of the visual-field index (VFI) of binocular-VFS with 3D shape perception in glaucoma patients was also examined.
RESULTS: Glaucoma patients demonstrated reduced accuracy in distinguishing 1D luminance brightness and a larger \"error-in-depth\" between the perceived and actual depths for 3D-SfM and 3D-SfS compared to healthy volunteers. Six glaucoma patients with a 100% VFI for binocular-VFS exhibited a similar error-in-depth to the other fourteen glaucoma patients; they had a larger error-in-depth for 3D-SfM compared to healthy volunteers. No correlation between the error-in-depth values and the VFI values of binocular-VFS was observed.
CONCLUSIONS: The 3D shape perception in glaucoma patients varies based on the depth cue\'s characteristics. Impaired 1D discrimination and larger thresholds for 3D-SfM in glaucoma patients with a 100% VFI for binocular-VFS indicate more pronounced perceptual deficits of lower-level elementary features for 3D-SfS and higher-level visual processing of 3D shapes for 3D-SfM. The effects of the location and degree of binocular visual-field defects on 3D shape perception remain to be elucidated. Our research provides insights into the 3D shape extraction mechanism in glaucoma.

OBJECTIVE: To assess long-term clinical results following bilateral Tecnis Symfony ZXR00 intraocular lens implantation with mini-monovision.
METHODS: The medical records of cataract patients who underwent bilateral implantation of ZXR00 with intended mini-monovision (target refraction of -0.3 diopters [D] in dominant eye and -0.6 D in nondominant eye) between April 2019 and March 2021 were assessed. Postoperative uncorrected distance visual acuity (UDVA), corrected distance VA (CDVA), uncorrected intermediate VA (UIVA), uncorrected near VA (UNVA), and rate of spectacle dependence for near distance were investigated at 3 months and 2 years after surgery.
RESULTS: This study included 61 patients (122 eyes) with average age of 61.8 ± 7.7 years. At 2 years postoperatively, binocular logarithm of the minimum angle of resolution UDVA, UIVA, UNVA, and CDVA were 0.086 ± 0.094, 0.056 ± 0.041, 0.140 ± 0.045, and 0.012 ± 0.024, respectively. The monocular manifest refraction spherical equivalent was -0.31 ± 0.38 in the dominant eye and -0.53 ± 0.47 in the nondominant eye at 3 months postoperatively, and -0.38 ± 0.43 in the dominant eye and -0.61 ± 0.54 in the nondominant eye at 2 years postoperatively. Eight out of 61 patients (13.1%) needed glasses 3 months after surgery, and nine out of 61 patients (14.8%) needed glasses 2 years after surgery.
CONCLUSIONS: The bilateral implantation of ZXR00s with mini-monovision allows for a good VA at wide range of distance from far to near, thereby resulting in high rate of spectacle independence. These results have held up well even after 2 years after surgery.

Mechanisms of object-based attention (OBA) are commonly associated with the cerebral cortex. However, less is known about the involvement of subcortical visual pathways in these processes. Knowledge of the neural mechanisms subserving OBA can provide insight into the evolutionary trajectory of attentional selection. In the current study, the classic double-rectangle cueing task was implemented using a stereoscope in order to differentiate between the involvement of lower (monocular) and higher (binocular) visual pathways in OBA processes. We found that monocular visual pathways are involved in two main aspects of OBA: exogenous orienting towards a cued object (Experiment 1; N =33) and attentional deployment within a cued object (Experiment 2; N =23); this is evident by the presence of OBA only when both the cue and target were presented to the same eye. Thus, these results indicate that monocular (mostly subcortical) visual regions are not simply passing information to higher cortical areas but have a functional computational role in OBA. These findings emphasize the importance of lower regions in attentional processes and, more specifically, in OBA.

OBJECTIVE: To provide the reports of a pilot study to assess the visual acuity (VA) and contrast sensitivity with RayOne enhanced monovision (EMV), a unique nondiffractive enhanced monofocal intraocular lens (IOL) to increase the range of focus.
METHODS: A retrospective case series study was conducted by analyzing 25 patients (50 eyes) who had bilateral implantation of EMV IOL after cataract surgery. Data collected included biometry, spherical equivalent (SE), and VA for near, intermediate, and distance. Patients were reviewed at 1 day, 1 week, and 1 month after surgery. Contrast sensitivity (CS) was checked at 1 month.
RESULTS: The study included 14 males (56%). Age of participants was 61.4 ± 7.4 years. Uniocular uncorrected near and distance VA improved from 0.33 ± 0.13 to 0.05 ± 0.07 and from 0.63 ± 0.31 to 0.05 ± 0.10 log of minimum angle of resolution (logMAR) at 1 month (P < 0.001 for both). Binocular uncorrected near and distance VA improved from 0.09 ± 0.18 and 0.14 ± 0.27 to 0.05 ± 0.06 and 0.00 ± 0.09 logMAR, respectively (P < 0.001). SE changed from - 0.23 ± 2.55 to - 0.33 ± 0.46. CS at 3 months was 1.74 ± 0.21. At 1 month, 48 eyes (96%) achieved uncorrected intermediate VA 6/15 (0.4 logMAR) or better. When comparing eyes that had uncorrected intermediate vision of ≥ 0.2 (6/9 or better) to eyes that had < 0.2 logMAR at 1 month, there was no difference between groups with respect to baseline parameters.
CONCLUSIONS: The pilot study shows that the nondiffractive EMV IOL is safe, effective, and stable, providing excellent distance and intermediate vision and good near vision.

Unlike ballistic arm movements such as reaching, the contribution of depth information to the performance of manual tracking movements is unclear. Thus, to understand how the brain handles information, we investigated how a required movement along the depth axis would affect behavioral tracking performance, postulating that it would be affected by the amount of depth movement. We designed a visually guided planar tracking task that requires movement on three planes with different depths: a fronto-parallel plane called ROT (0), a sagittal plane called ROT (90), and a plane rotated by 45° with respect to the sagittal plane called ROT (45). Fifteen participants performed a circular manual tracking task under binocular and monocular visions in a three-dimensional (3D) virtual reality space. As a result, under binocular vision, ROT (90), which required the largest depth movement among the tasks, showed the greatest error in 3D. Similarly, the errors (deviation from the target path) on the depth axis revealed significant differences among the tasks. Under monocular vision, significant differences in errors were observed only on the lateral axis. Moreover, we observed that the errors in the lateral and depth axes were proportional to the required movement on these axes under binocular vision and confirmed that the required depth movement under binocular vision determined depth error independent of the other axes. This finding implies that the brain may independently process binocular vision information on each axis. Meanwhile, the required depth movement under monocular vision was independent of performance along the depth axis, indicating an intractable behavior. Our findings highlight the importance of handling depth movement, especially when a virtual reality situation, involving tracking tasks, is generated.

OBJECTIVE: This study aimed to evaluate the difference between binocular and monocular vision and eye movements during the competition using video-oculography (VOG).
METHODS: Experiment 1 included 14 participants to evaluate differences in arrow convergence. Then, seven participants in Experiment 1 were randomly selected and included in Experiment 2, which evaluated eye movements during archery using VOG. The target used an 80-cm waterproof target face and was set at a distance of 30 m. All players shot the target 36 times using their bows and arrows. Experiments 1 and 2 evaluated the distribution of arrows in each score and the number of focus points, respectively, between binocular and monocular conditions.
RESULTS: The arrows, which include the area of 9 points, were significantly greater in the binocular condition (11.85 ± 5.04 shots) than in the monocular condition (9.36 ± 5.41 shots) in Experiment 1 (P = 0.047). The players focused on the target under both binocular and monocular conditions, although the players were switching off fixation between the target and shooting sight under the binocular condition in Experiment 2.
CONCLUSIONS: These behaviors indicated that the players were trying to accurately shoot the target by exploring the distance between themselves and the target as a cue for depth perception.