Normal Sight Research Articles

Development and validation of the Thai version of MNREAD acuity charts.

To develop and validate MNREAD acuity charts in the Thai language (MNREAD-TH). In total, 180 Thai sentences were generated using words specific to the primary 1-3 students. Each sentence contained 60 characters divided into three lines with even left and right margins and was evaluated by instructors in the education program in Thai. The selected 118 sentences were tested in 20 adults and 20 children by measuring reading time and recording the errors. Sentences with extremely high or low mean reading speeds were excluded. The remaining sentences were selected for contributing to the MNREAD-TH charts. For validation, the charts were tested in another 20 normal-sighted adult groups. In total, 118 sentences were tested on 20 adults (range: 23-58 years) and 20 primary school students (age: 8-9 years). The mean (SD) reading speeds in adult and children's groups were 134.09 (12.45) and 71.33 (10.77) words/min (wpm), respectively. After removing the sentences that deviated by ±1 SD from the mean reading speed, repeatedly had difficulty words, and had low subjective scoring, 60 matched sentences between the groups were selected to develop three versions of the MNREAD-TH chart. The intraclass correlation coefficients between charts were 0.85 for reading acuity, 0.94 for maximum reading speed, and 0.79 for critical print size. The MNREAD-TH charts can be reliably used for evaluating reading performance in Thai people for both children and adults with either normal sight or low vision. These charts are standardized and helpful in clinical trials involving reading.

Differences in Objective Physical Activity Between Children With Visual Impairment and Those With Normal Sight.

To compare objective physical activity (PA) levels of children with visual impairment (VI) and children with normal sight. One hundred children with VI and 100 age- and gender-matched normal-sighted peers 7 to 17years of age wore an ActiGraph for 1 week. Activity count per minute (cpm) was modeled using a series of generalized linear mixed-effects models including vision, age, sex, time of day, and vision by time of day interaction. PA outcomes included mean counts per minute and proportion of time spent on sedentary, light, moderate, and vigorous intensity PA. Data of 83 children with VI and 77 normal-sighted peers were included. Mean counts per minute were lower in children with VI (P < 0.001), especially during and after school. Children with VI were less sedentary (55%; 95% confidence interval [CI], 53-57) than children with normal sight before school (62%; 95% CI, 60-64) and over weekends: children with VI, 41% (95% CI, 39-43); children with normal sight, 45% (95% CI, 43-47). Yet, children with VI were more sedentary during school (36%; 95% CI, 34-37) compared with children with normal sight (30%; 95% CI, 29-32). They also spent more time performing light PA and less time performing moderate PA at school and vigorous PA across all periods of day (P < 0.001). Children with VI participated in light and moderate PA but did not perform as much vigorous PA as children with normal sight, especially during school hours. There is a need to promote more intense PA programs in schools tailored for children with VI.

Outside Looking In

In this autoethnographic narrative, I reflect on my journey through vision loss and life with visual impairment, which comprises so much more than loss alone. “Outside Looking In” serves as a triple entendre. It signifies a reflection on the internal aspects of my lived experiences. It embodies the barriers that I often feel between me, other people, and activities as I navigate the gap between normal sight and full blindness. It is also an invitation to the reader to view, as an outsider, these reflections through my eyes. Drawing on trials encountered in personal, professional, and academic settings, I hope to evoke awareness of the challenges faced, and to inform recommendations for support and understanding while allowing individuals to maintain autonomy. The account that emerges highlights the shared experiences of another with vision loss and the areas in which they diverge while also detailing a personal journey from frustration to integration, identity reformation, and resilience.

EYE-R : Augmented Reality as Mobile Based Helper Application for Colorblinds

The ability to identify color is a basic ability for a human to live easily. Unfortunately not all humans have normal sight, there are some humans who have an eye disorder called color blindness. Color blindness is an eye disorder that affects color perception of the affected person in everyday life, therefore the person that has color blindness needs a device to help them to identify some colors. In the medical world, the usage of Augmented Reality is still limited for education for medical practitioners, so the application of AR as a tool to help patients is still considered to be minimal. Augmented Reality as a Mobile Based Colorblind Helper Research aims to find out how effective a color detection system using AR as a tool to help the colorblinds identify color in an application called “EYE-R”. The research method employed in the research and development of this application is the Waterfall method that involves the stages of Requirements, Design, Programming, Testing, and Implementation. The main feature of “EYE-R” is chosen using a survey which is Real Time Color Detection which is developed using the Unity engine and implemented using Android. The research results show that the majority of users can operate the Real Time Color Detection system accurately. The user satisfaction results recorded using USE Questionnaire shows that the EYE-R Real Time Color Detection system really helps users’ daily lives and can be used very well.

Patient’s Perception Regarding Vision Related Quality of Life in Immediate Sequential and Delayed Sequential Bilateral Cataract Surgery

Cataract is the main cause of visual impairment and treatable blindness in the world and surgery can restore normal sight to the patients. In bilateral cataract patient, surgery in the second eye is as important and meaningful as surgery in the first eye and it can be performed by immediate sequential (ISBCS) and delayed sequential bilateral cataract surgery (DSBCS). There is no statistically significant difference in surgical complications, visual acuity or long term self-perceived visual function between these two methods. To adopt surgical procedure, to improve the patient’s satisfaction and to improve the quality of services, patient opinion should be a great concern. This evaluative study was done to find out various recommendations and suggestions from patients regarding merits &amp; demerits of both types of cataract surgery that will be helpful for the decision-maker and administrator for future practice of cataract surgery in Canada. In this study, vision related quality of life improved in both groups. Participants in DSBCS group experienced different types of difficulties during the gap period between first eye and second eye cataract surgery i.e. visual imbalance between the two eyes and difficulty in driving. They recommended and suggested that cataract surgery wait time should be reduced and the difficulties experienced during the gap period can be eliminated by adopting ISBCS procedure. Bangabandhu Sheikh Mujib Med. Coll. J. 2023;2(1): 07-13

Utility for Uncorrected Refractive Errors in Adolescent Schoolchildren in Kakamega County, Kenya.

Uncorrected refractive errors (UREs) present an enormous lifetime burden in children. Despite this, there is a dearth of knowledge on URE-related preference-based quality of life (QoL) in East Africa. This study demonstrates the positive impact of interventions on UREs; hence, it provides an empirical justification for advocacy to improve the QoL of children with URE. This study investigated the preference-based QoL (utility) for URE in school-going adolescents of Kakamega County, in Kenya. An observational cross-sectional study with multistage sampling was conducted on randomly selected secondary school adolescents. School-going adolescents in Forms 1 to 4 were clinically examined for the presence of URE and classified according to their URE types. Pre-screened students who met the selection criteria were classified into two groups: URE and normal sight. Participants in the normal-sight group were randomly selected from among screened students without URE. Selected participants were administered a previously validated adolescent-specific utility weighting instrument-Assessment of Quality of Life-Six Dimensions. A total of 330 participants aged 17.32 ± 1.60 years (URE, 17.50 ± 1.58 years; normal-sight, 17.15 ± 1.61 years) were included in the study. The mean utility score, as elicited by the Assessment of Quality of Life-Six Dimensions scoring algorithm, was better in the normal-sight group (URE, 0.496 ± 0.22; normal sight, 0.567 ± 0.25) at baseline, whereas the reverse was true at follow-up (URE, 0.655 ± 0.20; normal sight, 0.603 ± 0.25). In all cases, the differences were significant ( P < .05); however, there was no significantly better ( P > .05) utility elicited by any URE subtype at any given time point. Nonetheless, the URE group showed significantly better utility ( P < .05) after spectacle correction. Uncorrected refractive errors are associated with reduced utility in school-going adolescents, regardless of URE subtype. Spectacle correction resulted in a significantly improved utility for those with URE. Thus, this study recommends early public health strategies and spectacle interventions in schools for adolescents with URE.

Titelbild: Influence of Potassium Metal‐Support Interactions on Dendrite Growth (Angew. Chem. 23/2023)

Using advanced analytical techniques based on synchrotron and electron microscopy, Pengcheng Liu, David Mitlin et al. in their Research Article (e202300943) were able to “see” and understand the growth of body centered cubic potassium metal dendrites, depicted in the cover picture as corals growing underwater and away from normal sight. This is represented by the light rays shining down from above. The fish are peacock bass, indigenous to South America but also found in the warmer waters of Florida.

Cover Picture: Influence of Potassium Metal‐Support Interactions on Dendrite Growth (Angew. Chem. Int. Ed. 23/2023)

Using advanced analytical techniques based on synchrotron and electron microscopy, Pengcheng Liu, David Mitlin et al. in their Research Article (e202300943) were able to “see” and understand the growth of body centered cubic potassium metal dendrites, depicted in the cover picture as corals growing underwater and away from normal sight. This is represented by the light rays shining down from above. The fish are peacock bass, indigenous to South America but also found in the warmer waters of Florida.

Age-related normal limits for spatial vision.

To establish age-related, normal limits of monocular and binocular spatial vision under photopic and mesopic conditions. Photopic and mesopic visual acuity (VA) and contrast thresholds (CTs) were measured with both positive and negative contrast optotypes under binocular and monocular viewing conditions using the Acuity-Plus (AP) test. The experiments were carried out on participants (age range from 10 to 86 years), who met pre-established, normal sight criteria. Mean and ± 2.5σ limits were calculated within each 5-year subgroup. A biologically meaningful model was then fitted to predict mean values and upper and lower threshold limits for VA and CT as a function of age. The best-fit model parameters describe normal aging of spatial vision for each of the 16 experimental conditions investigated. Out of the 382 participants recruited for this study, 285 participants passed the selection criteria for normal aging. Log transforms were applied to ensure approximate normal distributions. Outliers were also removed for each of the 16 stimulus conditions investigated based on the ±2.5σ limit criterion. VA, CTs and the overall variability were found to be age-invariant up to ~50 years in the photopic condition. A lower, age-invariant limit of ~30 years was more appropriate for the mesopic range with a gradual, but accelerating increase in both mean thresholds and intersubject variability above this age. Binocular thresholds were smaller and much less variable when compared to the thresholds measured in either eye. Results with negative contrast optotypes were significantly better than the corresponding results measured with positive contrast (p < 0.004). This project has established the expected age limits of spatial vision for monocular and binocular viewing under photopic and high mesopic lighting with both positive and negative contrast optotypes using a single test, which can be implemented either in the clinic or in an occupational setting.

Effect of static and dynamic jaw positions on postural stability among people with blindness.

BackgroundIn comparison with the people with normal sight, the mean center of gravity (COG) velocity is significantly higher among blind people. A strong relationship has been shown between jaw and neck sensorimotor and postural control. The purpose of this study was to determine the effect of different static and dynamic jaw positions on postural stability among subjects with blindness.MethodsPostural stability was measured as COG velocity in 39 blind subjects under the following five conditions: resting jaw (natural jaw position with no instructions, control), open jaw (teeth of both jaws slightly apart), clenched jaw (teeth tightly closed across each other), chewing (a standard bolus of gum at the natural palace), and tongue position (positioned behind the upper incisors) while standing on firm and foam surfaces.ResultsThe mean COG velocity while standing on the firm surface during resting, open jaw position, clenched jaw position, chewing, and tongue positions were 0.54, 0.50, 0.44, 0.59, and 0.46 deg/s, respectively. The mean COG velocity while standing on the foam surface during resting, open jaw position, clenched jaw position, chewing, and tongue positions were 1.42, 1.23, 1.10, 1.14, and 1.06 deg/s, respectively. Compared to the firm surface, the COG velocity was significantly higher on the foam surface in all five conditions (p < .001). In the comparison between the conditions, there were no significant differences in either the firm or foam surface in all five conditions (p > .05).ConclusionPeople with blindness behave in the same way as sighted subjects on firm and foam surfaces. However, changes in static and dynamic jaw positions do not affect postural stability among them.

Physical Activity Is Associated with Improved Visuomotor Processing in Older Adults with Moderate and Advanced Glaucomatous Visual Field Defect: A Cross-Sectional Study.

Glaucoma affects a wide spectrum of daily essential activities in older adults. This study examined whether older adults with moderate and advanced stages of glaucoma exhibit differences in visuomotor task performance compared with age- and gender-matched ophthalmologically healthy control subjects and estimated the effects of physical activity (PA) levels, age, and severity of visual impairment on patients’ visuomotor task performance. Sixty older adults with moderate glaucoma, advanced glaucoma, and normal sight participated in the study. Visuomotor processing was assessed using laboratory-based simple and complex visuomotor reaction tasks. Monocular Humphrey Visual Field and binocular Humphrey Esterman Visual Field tests were used to estimate visual field defect severity. The International Physical Activity Questionnaire was used to assess PA levels. Participants with glaucoma had poorer scores in visuomotor tasks compared to participants with normal sight. Glaucoma patients’ PA levels, age, and binocular visual field defect explained 54% of the variation in complex reaction time. Low PA levels were identified as a risk factor for visuomotor processing decline. Compensatory mechanisms to improve the efficiency of visual field scanning in patients with more severe visual field defects may exist.

Research on Improvement of Optical Model of Human Vision

In retrospect, visional researches mostly focused on vision sensitivity. However, a vision model suitable to human eye shall be built to further explore human eye visional characteristics. Most of the vision models in the fields of optometry and physiological optics must be modified to bring them more closer to actual human eye characteristics. While the aforementioned potential problem would not impede the visual capability of a person with normal eye sight, it tends to cause significant implication for a patient with retina illness during the initial syndrome and recuperation period after surgical operation. Under some special circumstances, such as in a battle field when lack of light is norm due to weather and landform conditions, human eye recognition capability would be significantly compromised as well. The CSF (Contrast sensitivity function) curve is proposed to be applied to the analysis in evaluating human eye recognition characteristics problems. this is the first literature to incorporate CS(contrast sensitivity) correction into human vision multi-parameter model. The modified modeling is validated by the experiment results showing the modified model is closed to human eye’s CSF curve.

A Novel Wearable and Wireless Device to Investigate Perception in Interactive Scenarios.

The aim of the present work is to introduce a novel wearable device suitable to be used to investigate perception in interactive tasks, on individuals with and without sensory disabilities. The system is composed by small units embedded with sensors and actuators that allows emitting different kind of stimuli (light, haptic, sound) and to record the user response, thanks to a capacitive sensor. We validated the system by implementing an interception task in three different sensory modalities: visual, tactile and auditory. Six subjects with normal sight were asked to tap either a static or a moving stimulus generated by 6 units placed on their forearm. Results suggest that the system can effectively provide new insights in characterizing how perception principles vary when perceptual judgement occurs through different senses. This confirms the device potential in contributing to the design of rehabilitation protocols rooted on neuroscientific findings, for people with sensory impairments.

Neurological and behavioral features of locomotor imagery in the blind

In people with normal sight, mental simulation (motor imagery) of an experienced action involves a multisensory (especially kinesthetic and visual) emulation process associated with the action. Here, we examined how long-term blindness influences sensory experience during motor imagery and its neuronal correlates by comparing data obtained from blind and sighted people. We scanned brain activity with functional magnetic resonance imaging (fMRI) while 16 sighted and 14 blind male volunteers imagined either walking or jogging around a circle of 2 m radius. In the training before fMRI, they performed these actions with their eyes closed. During scanning, we explicitly instructed the blindfolded participants to generate kinesthetic motor imagery. After the experimental run, they rated the degree to which their motor imagery became kinesthetic or spatio-visual. The imagery of blind people was more kinesthetic as per instructions, while that of the sighted group became more spatio-visual. The imagery of both groups commonly activated bilateral frontoparietal cortices including supplementary motor areas (SMA). Despite the lack of group differences in degree of brain activation, we observed stronger functional connectivity between the SMA and cerebellum in the blind group compared to that in the sighted group. To conclude, long-term blindness likely changes sensory emulation during motor imagery to a more kinesthetic mode, which may be associated with stronger functional coupling in kinesthetic brain networks compared with that in sighted people. This study adds valuable knowledge on motor cognition and mental imagery processes in the blind.

Impact of visual and auditory deprivation on speech perception and production in adults

ABSTRACT Speech perception relies on auditory and visual cues and there are strong links between speech perception and production. We aimed to evaluate the role of auditory and visual modalities on speech perception and production in adults with impaired hearing or sight versus those with normal hearing and sight. We examined speech perception and production of three isolated vowels (/i/, /y/, /u/), which were selected based on their different auditory and visual perceptual saliencies, in 12 deaf adults who used one or two cochlear implants (CIs), 14 congenitally blind adults, and 16 adults with normal sight and hearing. The results showed that the deaf adults who used a CI had worse vowel identification and discrimination perception and they also produced vowels that were less typical or precise than other participants. They had different tongue positions in speech production, which possibly partly explains the poorer quality of their spoken vowels. Blind individuals had larger lip openings and smaller lip protrusions for the rounded vowel and unrounded vowels, compared to the other participants, but they still produced vowels that were similar to those produced by the adults with normal sight and hearing. In summary, the deaf adults, even though they used CIs, had greater difficulty in producing accurate vowel targets than the blind adults, whereas the blind adults were still able to produce accurate vowel targets, even though they used different articulatory strategies.

The association between visual impairment and fatigue: a systematic review and meta-analysis of observational studies.

PurposeThe aim was to compare fatigue levels between patients with visual impairment and controls with normal sight and to examine the association between fatigue and vision loss severity.MethodsA systematic literature search was performed using databases of PubMed, Embase, PsycINFO and Cochrane to identify observational studies with outcomes related to fatigue (e.g. vitality subscale of the Short‐Form 36, Fatigue Assessment Scale). A meta‐analysis was performed using standardised mean differences (SMDs) and odds ratios (OR) to quantitatively summarise the association between visual impairment and fatigue. Sources of heterogeneity were explored by subgroup and sensitivity analyses. Study quality was assessed with the Newcastle‐Ottawa scale.ResultsAfter reviewing 4477 studies, 22 studies with a total of 40 004 participants were included, of which 18 contributed to meta‐analysis. Among these, eight were assessed as moderate quality studies and 10 as high quality studies. Pooled analysis involving 2500 patients and 8395 controls showed higher fatigue severity levels (S.M.D. = −0.36, 95% CI −0.50 to −0.22, 14 studies) among visually impaired patients compared to normally sighted controls. This effect size was small and persisted in sensitivity analyses that involved study quality, fatigue assessment tools and visual acuity data. Furthermore, pooled analysis of four studies including 2615 patients and 5438 controls showed a significant association between visual impairment and fatigue (OR = 2.61, 95% CI 1.69 to 4.04). Secondary meta‐analysis of four studies showed no significant difference in fatigue severity (S.M.D. = 0.01, 95% CI −0.37 to 0.39) between patients with moderate visual impairment and patients with severe visual impairment or blindness.ConclusionsCurrent moderate to high quality evidence suggest that patients with visual impairment experience more severe fatigue symptoms than persons with normal sight. However, a limited number of available studies indicates that fatigue is not associated with severity of vision loss. Future studies are required to determine which factors and underlying mechanisms may explain the association between visual impairment and fatigue. Discussing fatigue at an early stage and developing intervention options for vision‐related fatigue should be considered within the field of low vision rehabilitation.

Understanding fatigue in adults with visual impairment: Apath analysis study of sociodemographic, psychological and health-related factors.

BackgroundFatigue is a disabling problem in patients with visual impairment, but its etiology is still poorly understood. Our objective was to identify the determinants of fatigue in adults with visual impairment compared to adults with normal sight.MethodsCross-sectional data on fatigue and sociodemographic, psychological and health-related factors was obtained with validated questionnaires. Structural equational modeling using hypothesized relationships and explorative analyses were used to identify (in)direct pathways contributing to fatigue in 247 adults with visual impairment. The model was then tested in a reference group of 151 adults with normal sight.ResultsThe final model explained 64% of fatigue variance in participants with visual impairment and revealed the following factors to be directly associated with fatigue: depressive symptoms (β = 0.723, p<0.001), perceived health (β = -0.158, p = 0.004), accommodative coping (β = 0.116, p = 0.030) and somatic comorbidity (β = 0.311, p = 0.001). Self-efficacy demonstrated a beneficial indirect effect on fatigue (β = -0.228, p<0.001) mediated by depression, accommodative coping and perceived health. Sleep disorder had an indirect effect on fatigue (β = 0.656, p<0.001) mediated by depression and perceived health. After removal of sleep disorder, the model explained 58% of the fatigue variance in normally sighted adults but pathways involving accommodative coping and somatic comorbidity were not confirmed.ConclusionsThese findings suggest that depression and perceived health are important mediating factors that contribute to fatigue in persons with visual impairment and normal sight. In contrast, somatic comorbidity, sleep disorders and accommodative coping seem to have a specific contribution to vision-related fatigue. These factors should be addressed in interventions to assist individuals with visual impairment in dealing with fatigue.

A Research on QoS Optimization in 4G Cellular Networks

cellular system conveys sight and sound website online traffic productively during ongoing transmission. in view that this device transmits blended media information, there may be a prerequisite to adjust the management price as indicated via the gadget situations an excellent manner to hold up fruitful device hobby. in the end, there is a need to allot the assets capably. Nature of provider (QoS) improvement within the sort of system is additionally trying out specially in 4G cellular systems. severa plans were proposed for QoS development in cellular structures which be a part of name Admission control (CAC) and electricity control Scheme. Be that as it is able to, CAC with electricity control isn't always sufficient to offer the most ideal asset use. alongside the ones lines, it is straightforward to build up an powerful QoS primarily based definitely resource Allocation and Scheduling Scheme for normal sight and sound site visitors. The primary objective of proposed studies paintings is to build up a nice of provider based resource Allocation and Adaptive rate Scheduling (QRAAS) plot in cellular systems to improve prepare dependability, boom the framework limit and enhance framework proficiency and therefore to improve best of service in cell systems. To execute the formerly stated QRAAS conspire, resource Allocation based definitely call Admission manage (RACAC) plan and Adaptive price Scheduling (ARS) plot were created.

Just the Start of the Journey

In under three years, the UK Autodrive project has led to autonomous pods becoming a normal sight on the pavements of Milton Keynes. What has been learned?

Does Central Vision Loss Impair Visual Search Performance of Adults More than Children?

In general, young adults with normal vision show the best visual search performance when compared with children and older adults. Through our study, we show that this trend is not observed in individuals with vision impairment. An interaction effect of vision impairment with visual development and aging is observed. Performance in many visual tasks typically shows improvement with age until young adulthood and then declines with aging. Using a visual search task, this study investigated whether a similar age effect on performance is present in people with central vision loss. A total of 98 participants, 37 with normal sight (NS) and 61 with visual impairment (VI) searched for targets in 150 real-world digital images. Search performance was quantified by an integrated measure combining speed and accuracy. Participant ages ranged from 5 to 74 years, visual acuity from -0.14 (20/14.5) to 1.16 logMAR (20/290), and log contrast sensitivity (CS) from 0.48 to 2.0. Data analysis was performed with participants divided into three age groups: children (aged <14 years, n = 25), young adults (aged 14 to 45 years, n = 47), and older adults (aged >45 years, n = 26). Regression (r = 0.7) revealed CS (P < .001) and age (P = .003) were significant predictors of search performance. Performance of VI participants was normalized to the age-matched average performance of the NS group. In the VI group, it was found that children's normalized performance (52%) was better than both young (39%, P = .05) and older (40%, P = .048) adults. Unlike NS participants, young adults in the VI group may not have search ability superior to children with VI, despite having the same level of visual functions (quantified by visual acuity and CS). This could be because of vision impairment limiting the developmental acquisition of the age dividend for peak performance. Older adults in the VI group had the worst performance, indicating an interaction of aging.