Visual Conditions Research Articles

Types of Refractive Error in Pediatric Low Vision Condition

Types of Refractive Error in Pediatric Low Vision Condition

Layers of inhibitory networks shape receptive field properties of AII amacrine cells

In the retina, rod and cone pathways mediate visual signals over a billion-fold range in luminance. AII ("A-two") amacrine cells (ACs) receive signals from both pathways via different bipolar cells, enabling AIIs to operate at night and during the day. Previous work has examined luminance-dependent changes in AII gap junction connectivity, but less is known about how surrounding circuitry shapes AII receptive fields across light levels. Here, we report that moderate contrast stimuli elicit surround inhibition in AIIs under all but the dimmest visual conditions, due to actions of horizontal cells and at least two ACs that inhibit presynaptic bipolar cells. Under photopic (daylight) conditions, surround inhibition transforms AII response kinetics, which are inherited by downstream ganglion cells. Ablating neuronal nitric oxide synthase type-1 (nNOS-1) ACs removes AII surround inhibition under mesopic (dusk/dawn), but not photopic, conditions. Our findings demonstrate how multiple layers of neural circuitry interact to encode signals across a wide physiological range.

SELF-ESTEEM PADA REMAJA TUNANETRA DI BALI

Abstract. Visual impairment defined as an individual whose senses of sight cannot function properly as a channel for obtaining visual information. Visually impaired persons, including visually impaired adolescents, must continue to fulfil their developmental tasks and carry out activities as normal individuals. Therefore, one of the important internal factors in influencing individual personality is needed, namely self-esteem. This study aimed to determine (a) the categorization of self-esteem levels among visually impaired adolescents in Bali and (b) the influence of sociodemographic variables: gender, visual condition, age of onset, stage of developmental age, level of education, and socioeconomic status. The subjects in this study were 64 visually impaired adolescents, aged 10 to 22 years in Bali. This research was a descriptive quantitative study with a self-esteem scale. The results showed that the majority of participants, as many as 39 people, had high levels of self-esteem and all sociodemographic variables analyzed in this study had no significant effect on self-esteem (p > 0.05). The results of this research are expected to provide theoretical knowledge of psychology as well as practical knowledge for related parties such as visually impaired adolescents, parents, and educational institutions in effort to form and increase self-esteem in visually impaired adolescents.

PSV-19 Evaluation of Dietary Fiber Inclusion on Body Weight, Body Condition, Fecal Score, and Metabolic Indicators in Mature AI Boars

Abstract This experiment was conducted at the Purdue University swine research and education center. The objective of this study was to determine if the inclusion of fiber (8.48% vs 14.85% NDF) in the diet influenced boar body weight, backfat depth, loin depth, Knauer sow caliper measurement, flank to flank distance, and visual body condition score (BCS). Twenty-seven boars from two age groups (7 months and 18 months) and two genetic lines (maternal and terminal) were utilized over a 12-week period with 1 week before the study data serving as baseline for statistical analysis. Fecal samples were also taken and scored using the Bristol stool scoring system. Timepoints for sample collection were on weeks -1,3,7, and 11. Boars were blocked by age and breed and randomly allotted to receive 2.72 kg/d of corn-soybean meal diet (CON, n = 13) formulated to meet NRC (2012) requirements or an isocaloric (estimated ME = 3,285 Kcal/kg) corn-soybean meal diet with 14.3% soyhulls and supplemental choice white grease (4.65%) inclusions (FIBER, n = 14). Data were analyzed using PROC GLM in SAS 9.4 (Cary, North Carolina) with boar serving as the experimental unit. Weeks were analyzed individually and changes in body weight, backfat depth, loin depth, caliper measurements, flank to flank distance, and BCS were evaluated from week -1 to week 12. Significance was determined at P < 0.05 and a trend was observed at 0.05 < P ≤ 0.10. FIBER boars gained 8.4 kg more than CON boars during the 12-week study (P = 0.0221). On weeks 3 and 11, FIBER boars tended to have increased backfat depth compared with CON boars (P < 0.0950), resulting in FIBER boars gaining 2.9 mm more backfat compared with CON (P = 0.0053) over the 12-week study. No difference in loin muscle depth was observed between treatments. On weeks 7 (3.7 vs 3.4, P = 0.0923) and 11(3.9 vs 3.5, P = 0.0615) FIBER boars tended to have greater BCS score compared with Con boars. FIBER boars on week 11 tended to have larger tape measurements (105.9 cm vs 103.9 cm, P = 0.0945) and larger caliper score (19.4 vs 17.6, P = 0.0029) than CON boars, but no difference in overall 12 week change for both measurements. FIBER boars tended to have softer stools during week 3 of the trial compared with CON boars (P = 0.0535), but the fecal scores were not different at any other week. Overall, boars fed a high fiber diet had increased body weight, backfat depth and BCS indicating an underestimation of the net energy value of soyhulls in limit fed boars. Future research is needed with varying levels and types of fiber inclusion in the diet to understand how to correctly implement fiber into the boar diet and to refine the net energy values of fibrous feedstuffs like soyhulls for boars.

Visual performance of new affordable and auto-adherent lenses for presbyopia correction.

Presbyopia is a visual condition that affects all of us, evolving with time, reducing the range of accommodation and the ability to work at near. Reading glasses, bifocals or multifocal lenses are the most common solutions. In this work, we demonstrate the near visual performance of new elastomeric auto-adherent lenses developed for the correction of presbyopia. Visual acuity and contrast sensitivity were measured in 10 presbyopic subjects. The results showed that wearing either conventional trial ophthalmic lenses or the new elastomeric lenses provided similar visual quality. These elastomeric lenses can be placed in, or removed from the distance-vision spectacles of the wearers, providing an affordable solution for correcting presbyopia at its clinical onset, which might be especially useful in subjects with different refractive error in each eye and for those with astigmatism.

Joint Contributions of Auditory, Proprioceptive and Visual Cues on Human Balance

Abstract One’s ability to maintain their center of mass within their base of support (i.e., balance) is believed to be the result of multisensory integration. Much of the research in this literature has focused on integration of visual, vestibular, and proprioceptive cues. However, several recent studies have found evidence that auditory cues can impact balance control metrics. In the present study, we sought to better characterize the impact of auditory cues on narrow stance balance task performance with different combinations of visual stimuli (virtual and real world) and support surfaces (firm and compliant). In line with past results, we found that reducing the reliability of proprioceptive cues and visual cues yielded consistent increases in center-of-pressure (CoP) sway metrics, indicating more imbalance. Masking ambient auditory cues with broadband noise led to less consistent findings; however, when effects were observed they were substantially smaller for auditory cues than for proprioceptive and visual cues — and in the opposite direction (i.e., masking ambient auditory cues with broadband noise reduced sway in some situations). Additionally, trials that used virtual and real-world visual stimuli did not differ unless participants were standing on a surface that disrupted proprioceptive cues; disruption of proprioception led to increased CoP sway metrics in the virtual visual condition. This is the first manuscript to report the effect size of different perturbations in this context, and the first to study the impact of acoustically complex environments on balance in comparison to visual and proprioceptive contributions. Future research is needed to better characterize the impact of different acoustic environments on balance.

Weighting of visual and auditory inputs in dancers with and without previous ankle injury

Elite dance requires highly controlled balance performance in dynamic visual and auditory environments characterized by the use of stage lighting and music. Perturbing visual input is known to influence balance in dancers, but the effects of sounds have not been clearly established. Ankle inversion injuries are common in dancers and may also play a role in dancers' ability to respond to sensory perturbations. The aims of this study were to identify changes in static balance in response to visual or auditory perturbation in elite collegiate dancers with and without a history of ankle injury, and to describe coupling of measurements obtained from the waist and head during balance. Thirty-seven dancers: 22 controls and 15 with a history of ankle sprain, performed single-leg balance under static and dynamic visual and auditory conditions. Dancers demonstrated increased waist sway when viewing a dynamic visual scene and when presented with moving sounds and increased head sway with dynamic visuals. These results did not vary by history of ankle sprain. While dancers appear to dampen the impact of waist sway on head motion during single leg stance, even highly trained dancers may experience challenges controlling balance under perturbing visual and auditory conditions like those present during stage performance.

Refractive Laser Surgery for Vision Conditions


 None of the identified studies were of sufficient quality to formulate conclusions on the clinical effectiveness of refractive laser surgeries compared to conventional vision correction for people with vision conditions.
 
 The identified evidence for the clinical effectiveness of photorefractive keratotomy (PRK) was limited to 1 low-quality study that did not detect a visual acuity difference between participants who had PRK and participants who wore contact lenses.
 Low-quality evidence from 1 study found participants who had undergone PRK had greater vision-related quality of life (QoL) than participants who had not had PRK. Another low-quality study found that participants who wore contact lenses had greater vision-related QoL than participants who had undergone a laser-assisted in situ keratomileusis (LASIK) procedure.
 Low-quality evidence suggested that contact lenses resulted in fewer incidences of vision loss events than LASIK.
 
 
 No evidence-based guidelines on best practices for refractive laser surgeries met the criteria for this review.

The effect of modality and order presentation of emotional stimuli on time perception.

Despite human accuracy in perceiving time, many factors can modulate the subjective experience of time. For example, it is widely reported that emotion can expand or shrink our perception of time and that temporal intervals are perceived as longer when marked by auditory stimuli than by visual stimuli. In the present study, we aimed at investigating whether the influence of emotion on time perception can be altered by the order in which emotional stimuli are presented and the sensory modality in which they are presented. Participants were asked to complete a time bisection task in which emotional stimuli were presented either acoustically or visually, and either before or after interval to be estimated. We observed a main effect of modality (longer perceived duration and lower variability in the auditory than in the visual modality) as well as a main effect of emotion (temporal overestimation for negative stimuli compared to neutral). Importantly, the effects of modality and emotion interacted with the order of presentation of the emotional stimuli. In the visual condition, when emotional stimuli were presented after the temporal intervals, participants overestimated time, but no differences between negative and neutral stimuli were observed when emotional stimuli were presented first. In the auditory condition, no significant effect of emotion on perceived duration was found. Results suggest that negative emotions affect our perception of durations acting at the decision-making stage rather than at the pacemaker one. No effect on time perception was observed for emotional auditory stimuli.

Effects of sensory integration training on balance function and executive function in children with autism spectrum disorder: evidence from Footscan and fNIRS

IntroductionThis study investigates the efficacy of sensory integration training (SIT) in enhancing balance and executive functions in children with autism spectrum disorder (ASD), with the aim of highlighting its potential for organizing and processing sensory information in the brain.MethodsUtilizing Footscan for biomechanical evidence and functional near-infrared spectroscopy (fNIRS) for neural activation, we engaged two participant groups: a control group (n = 9) and an experimental group (n = 9). Assessments involved the Sharpened Romberg Test (SRT) for balance under varied visual conditions and the Go/No-Go task for executive function.ResultsThe SIT intervention significantly improved balance function, particularly in Visual Deprivation (VD) scenarios. Neurophysiological data revealed heightened activation in the right Inferior Frontal Gyrus (R-IFG) and right Middle Frontal Gyrus (R-MFG), suggesting enhanced executive function. The potential of R-IFG/MFG activation as a reliable biomarker for assessing executive function in ASD was identified.DiscussionThe study provides empirical evidence supporting SIT’s effectiveness in enhancing balance and executive functions in children with ASD. The therapy not only improves sensory processing and motor skills but also appears to compensate for sensory deficits, particularly in vision, vestibular perception, and proprioception. Enhanced neural activation in specific PFC regions underscores SIT’s role in improving cognitive aspects, including inhibitory control and cognitive flexibility. The multidisciplinary approach adopted for this research highlights the intricate interplay between sensory-motor functions and cognitive control in ASD, paving the way for integrated therapeutic strategies. Despite these advancements, the mechanisms through which SIT exerts these multifaceted effects require further exploration.

Effective factors of icons searching performance based on visual attention capture for the nuclear power plants

AbstractWith the rapid development of digital and intelligent information systems, the display of visual information on interfaces has become an important challenge in the field of human‐computer interaction, as well as the human‐computer interface of nuclear power plants. This paper examines effective factors affecting visual attention capture based on icons related to the human‐computer interface of nuclear power plants. Experiments were conducted on multiple factors of visual search tasks with reference to information features to analyze information display factors affecting visual cognitive performance. The experimental results showed that the three factors, icon shape, feature display, and target position, have a great effect on information searching performance. The main effect of reaction time on three factors all reached a significance level congruent with the effect on fixation time and pupil response. Eye gaze indexes of feature display factors presented an increasing trend, which indicates that the information block spends more time on cognitive processing than icon features in the human‐computer interface of nuclear power plants. Pupil diameter was dilated when searching icons under difficult visual cognition conditions, and when searching information blocks, pupils were dilated more than searching single icons. Therefore, shape highlighting of data icons in the human‐computer interface of nuclear power plants can effectively improve the attention capture of the operator's visual search, and the ease of icon discrimination is an influential factor in visual attention capture.

Visual feedback modulates the 1/f structure of movement amplitude time series.

In our prior studies, human participants were required to generate long sequences of targeted hand movement when task difficulty varied between conditions, and where full vision of the hand and target was always available. The movement amplitude-that is, the actual distance travelled-for each movement was measured; consecutive movement amplitude values were formed into time series; then, the time series were submitted to spectral analysis. As task difficulty increased, there was a pink-to-white-noise shift in movement amplitude time-series structure. Those changes could be attributed to a difficulty-induced increase in the need to engage visual feedback processes, which maintain accurate guidance of the hand to the target. The current study was designed to provide a more direct test of the hypothesis that difficulty-induced increases in visual feedback processing modulate movement amplitude time-series structure. To that end, we examined cyclical aiming performance under four unique conditions created from the crossing of two index of difficulty (2 and 5 bits) and two visual feedback (visual feedback and no-visual feedback) conditions. That allowed us to examine how variations in visual feedback quality might influence difficulty-induced changes in time-series structure. In the visual feedback condition, we predicted that the increase in difficulty should result in a pink-to-white-noise shift in time-series structure. If that expected shift resulted from increased engagement of visual feedback processing, then in the no-visual feedback condition-where visual feedback processing was disabled-we should observe a strengthened pink-noise time-series structure that does not change with the increase in difficulty. The current results confirmed those predictions. That provides further support for the hypothesis that engagement of closed-loop visual feedback processing modulates movement amplitude time-series structure.

Opsin 5 mediates violet light-induced early growth response-1 expression in the mouse retina

Myopia is an abnormal vision condition characterized by difficulties in seeing distant objects. Myopia has become a public health issue not only in Asian countries but also in Western countries. Previously, we found that violet light (VL, 360–400 nm wavelength) exposure effectively suppressed myopia progression in experimental chick and mice models of myopia. The inhibitory effects of VL on myopia progression are reduced in retina-specific opsin 5 (Opn5) knockout (KO) mice. Furthermore, VL exposure upregulated early growth response-1 (Egr-1) expression in the chorioretinal tissues of chicks. However, the expression of EGR-1 and role of OPN5 in mice following VL exposure remain unclear. In this study, we examined whether VL exposure-induced EGR-1 upregulation depends on Opn5 expression in the mouse retina. EGR-1 mRNA and protein expressions increased in the mouse retina and mouse retinal 661W cells following VL exposure. These increases were consistently reduced in retina specific Opn5 conditional KO mice and Opn5 KO 661W cells. Our results suggest that OPN5 mediates VL-induced EGR-1 upregulation in mice. These molecular targets could be considered for the prevention and treatment of myopia.

Smart battery-free and wireless bioelectronic platform based on a nature-skin-derived organohydrogel for chronic wound diagnosis, assessment, and accelerated healing

Using smart electroactive hydrogels with emerging bioelectronics to monitor wound status wirelessly in real-time is a promising approach as an unremitting therapy for refractory chronic wounds. Based on a natural skin-derived organohydrogel (SGC@MA-Gel) triboelectric nanogenerator, a bioresorbable, battery-free, and wireless smart wound treatment bioelectronic system for pharmacological treatment, nanogenerator-driven electrostimulation, and visual wound condition assessment was engineered in this study. The inherent hierarchical architecture and origins of natural skin, in tandem with the substantial loading capabilities of collagen-based biomaterials, endowed SGC@MA-Gel with favorable characteristics. These included mechanical and adhesive robustness, electrical conductivity, antibacterial properties, controlled on-demand drug release capabilities, and human physiological signal monitoring performance. The customizable bioelectronic system, developed in-house, employs a single-electrode triboelectric nanogenerator, which facilitates skin wound healing via electrostimulation. Consequently, the system's biosensors can simultaneously measure glucose, uric acid, and pH at wound sites, thereby enabling accurate wound diagnosis and real-time assessment. This system accelerates cell proliferation and wound healing in vitro and in vivo, which validates its effectiveness in chronic wound treatment. The results demonstrated that the smart wound treatment bioelectronic system could provide a facile therapeutic strategy to assist with integrated wound monitoring, diagnosis, and therapy for hospitalized patients and those recovering at home.

Analysis Of In-service Traffic Sign Visual Condition: An Overview

This paper offers a comprehensive review of methodologies to assess the visual condition of traffic signs. It explores image processing, machine learning, and computer vision techniques to evaluate degradation, readability, and overall visibility. The objective is to enhance maintenance and effectiveness of traffic sign systems for safer roads. Regular assessment of traffic signs is vital for their efficacy and safety, considering factors like damage, fading, obstruction, and placement. Addressing these issues can significantly enhance road safety by enabling precise and safe navigation for drivers. The study delves into various aspects including shape, background color, symbol color, temperature, land use, visibility distance, and prevailing visibility conditions of traffic signs.

The effects of distraction on younger drivers: A neurophysiological perspective

Distracted driving remains a significant cause of traffic accidents globally, including in Australia. However, many younger drivers still admit to using a phone while driving. A simulated driving study investigated the neurophysiological effects of visual, auditory, and higher-order cognitive (i.e., requiring the use of executive functions) distraction on young drivers. In total, 24 young adults aged 18–25 years completed four 8 min simulated driving sessions while concurrently engaging in various distractor tasks. Neurophysiological arousal was measured via EEG. Additionally, subjective workload and objective driving performance were assessed. Frontal beta and gamma power exhibited their highest levels during tasks involving higher-order cognitive and visual demands. The higher-order cognitive condition was rated as the most mentally demanding. In comparison, the visual condition had the most significant impact on both the standard deviation of speed and standard deviation of lateral positioning. This study has significant implications for all road users, particularly those aged 18–25 years, and it reinforces the importance of not using a phone while driving.

Use of the sun compass by monocularly occluded homing pigeons in a food localisation task in an outdoor arena

Functional asymmetries of the avian visual system can be studied in monocularly occluded birds, as their hemispheres are largely independent. Right and left monocularly occluded homing pigeons and control birds under binocular view have been trained in a food localisation task in an octagonal outdoor arena provided with one coloured beacon on each wall. The three groups were tested after the removal of the visual beacons, so to assess their sun compass learning abilities. Pigeons using the left eye/right hemisphere system exhibited slower learning compared to the other monocular group. During the test in the arena void of visual beacons, the three groups of birds, regardless of their visual condition, were generally able to identify the training sector by exclusively relying on sun compass information. However, the directional choices of the pigeons with the left eye/right hemisphere in use were significantly affected by the removal of the beacons, while both control pigeons and birds with the right eye/left hemisphere in use displayed unaltered performances during the test. A subsample of pigeons of each group were re-trained in the octagonal arena with visual beacons present and tested after the removal of visual beacons after a 6 h fast clock-shift treatment. All birds displayed the expected deflection consistent to the sun compass use. While birds using either the left or the right visual systems were equally able to learn a sun compass-mediated spatial task, the left eye/right hemisphere visual system displayed an advantage in relying on visual beacons.

Reliability of on-line visual feedback influences learning of continuous motor task of healthy young adults.

A continuous task was used to determine how the reliability of on-line visual feedback during acquisition impacts motor learning. Participants performed a right hand pointing task of a repeated sequence with a visual cursor that was either reliable, moderately unreliable, or largely unreliable. Delayed retention tests were administered 24 h later, as well as intermanual transfer tests (performed with the left hand). A visuospatial transfer test was performed with the same targets' sequence (same visuospatial configuration) while a motor transfer test was performed with the visual mirror of the targets' sequence (same motor patterns). Results showed that pointing was slower and long-term learning disrupted in the largely unreliable visual cursor condition, compared with the reliable and moderately unreliable conditions. Also, analysis of transfers revealed classically better performance on visuospatial transfer than on motor transfer for the reliable condition. However, here we first show that such difference disappears when the cursor was moderately or largely unreliable. Interestingly, these results indicated a difference in the type of sequence coding, depending on the reliability of the on-line visual feedback. This recourse to mixed coding opens up interesting perspectives, as it is known to promote better learning of motor sequences.

Scaling up = scaling down? Children’s spatial scaling in different perceptual modalities and scaling directions

The present study examined whether scaling direction and perceptual modality affect children’s spatial scaling. Children aged 6–8 years (N = 201) were assigned to a visual, visuo-haptic, and haptic condition in which they were presented with colourful, embossed graphics. In the haptic condition, they were asked to wear a blindfold during the test trials. Across several trials, children were asked to learn about the position of a target in a map and to localize a disc at the same location in a referent space. Scaling factor was manipulated systematically, so that children had to either scale up or scale down spatial information. Their absolute deviations from the correct target location, reversal and signed errors, and response times served as dependent variables. Results revealed higher absolute deviations and response times for the haptic modality as opposed to the visual modality. Children’s signed errors, however, showed similar response strategies across the perceptual conditions. Therefore, it seems that a functional equivalence between vision and touch seems to emerge slowly across development for spatial scaling. With respect to scaling directions, findings showed that absolute deviations were affected by scaling factors, with symmetric increases in scaling up and scaling down in the haptic condition. Conversely, children showed an unbalanced pattern in the visual conditions, with higher accuracy in scaling down as opposed to scaling up. Overall, our findings suggest that visibility seems to factor into children’s scaling process.

Pre-movement event-related potentials and multivariate pattern of EEG encode action outcome prediction.

Self-initiated movements are accompanied by an efference copy, a motor command sent from motor regions to the sensory cortices, containing a prediction of the movement's sensory outcome. Previous studies have proposed pre-motor event-related potentials (ERPs), including the readiness potential (RP) and its lateralized sub-component (LRP), as potential neural markers of action feedback prediction. However, it is not known how specific these neural markers are for voluntary (active) movements as compared to involuntary (passive) movements, which produce much of the same sensory feedback (tactile, proprioceptive) but are not accompanied by an efference copy. The goal of the current study was to investigate how active and passive movements are distinguishable from premotor electroencephalography (EEG), and to examine if this change of neural activity differs when participants engage in tasks that differ in their expectation of sensory outcomes. Participants made active (self-initiated) or passive (finger moved by device) finger movements that led to either visual or auditory stimuli (100 ms delay), or to no immediate contingency effects (control). We investigated the time window before the movement onset by measuring pre-movement ERPs time-locked to the button press. For RP, we observed an interaction between task and movement. This was driven by movement differences in the visual and auditory but not the control conditions. LRP conversely only showed a main effect of movement. We then used multivariate pattern analysis to decode movements (active vs. passive). The results revealed ramping decoding for all tasks from around -800 ms onwards up to an accuracy of approximately 85% at the movement. Importantly, similar to RP, we observed lower decoding accuracies for the control condition than the visual and auditory conditions, but only shortly (from -200 ms) before the button press. We also decoded visual vs. auditory conditions. Here, task is decodable for both active and passive conditions, but the active condition showed increased decoding shortly before the button press. Taken together, our results provide robust evidence that pre-movement EEG activity may represent action-feedback prediction in which information about the subsequent sensory outcome is encoded.