Exceptionally low prevalence of refractive error and visual impairment in schoolchildren from Lao People's Democratic Republic.

PubMed

Casson, Robert J; Kahawita, Shyalle; Kong, Aimee; Muecke, James; Sisaleumsak, Siphetthavong; Visonnavong, Vithoune

2012-10-01

Vientiane Province is an urbanizing region in Southeast Asia. We aimed to determine the prevalence of refractive error and visual impairment in primary school-aged children in this region. Prospective, cross-sectional survey. A total of 2899 schoolchildren from Vientiane Province, Lao People's Democratic Republic (Lao PDR). Ten districts from Vientiane were randomly selected and 2 primary schools were randomly selected from each district. All children aged 6 to 11 years at selected schools were eligible to participate. The examination included visual acuity (VA) testing, cycloplegic retinoscopy with subjective refinement if indicated, ocular motility testing, and anterior segment and fundus examinations in visually impaired children. Cycloplegic refraction and VA. There was an estimated total of 3330 children who were eligible to participate, and data were recorded from 2899 (87%) of these children. Complete refractive data were available on 2842 children (85% of eligible population). The mean spherical equivalent (SE) in the right eyes was +0.60 diopter (D) (95% confidence interval [CI], 0.49-0.72), and the mean SE in the left eyes was +0.59 (95% CI, 0.50-0.68). The prevalence of hyperopia was 2.8% (95% CI, 1.9-3.7; 88 subjects), and the prevalence of myopia was 0.8% (95% CI, 0.3-1.4; 24 subjects). The majority of children (98%; 95% CI, 97.0-99.0) had normal unaided binocular VA (at least 20/32 in their better eye). The overall prevalence of any visual impairment (presenting VA <20/32 in the better eye) was 1.9% (95% CI, 1.0-2.9; 55 subjects). In multivariate logistic regression analysis, age (P = 0.001) was a significant predictor, and female gender (P = 0.08) and Yao ethnicity (P = 0.09) were borderline significant predictors of the presence of any visual impairment. Visual impairment is not a public health concern in this primary school-aged population; however, visually impaired children in the community were not studied. From this baseline, future surveys could determine the effect of increasing urbanization on myopia prevalence in this population. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Moving beyond the White Cane: Building an Online Learning Environment for the Visually Impaired Professional.

ERIC Educational Resources Information Center

Mitchell, Donald P.; Scigliano, John A.

2000-01-01

Describes the development of an online learning environment for a visually impaired professional. Topics include physical barriers, intellectual barriers, psychological barriers, and technological barriers; selecting appropriate hardware and software; and combining technologies that include personal computers, Web-based resources, network…

The Prevalence and Causes of Visaual Impairment and Blindness in a Rural Population in the North of Iran

PubMed Central

HASHEMI, Hassan; REZVAN, Farhad; YEKTA, AbbasAli; OSTADIMOGHADDAM, Hadi; SOROUSH, Sara; DADBIN, Nooshin; KHABAZKHOOB, Mehdi

2015-01-01

Background: Visual impairment is a very important public health problem. In Iran, reports of visual impairment and blindness have been published from the urban population while the prevalence of visual impairment in the rural population has not been reported. The purpose of this study to determine the prevalence and causes of visual impairment, in a rural population in district of based on age and sex Methods: In a cross-sectional population-based study, using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Eye examinations were performed in a Mobile Eye Clinic (Nooravaran Salamat, 2011) and included optometric examinations such as measuring uncorrected and corrected visual acuity along with non-cycloplegic refraction. Results: The prevalence of visual impairment, low vision, and blindness was 6.3% (95% CI 5.3–7.3), 3.4% (95% CI 2.6–4.1), and 3.0% (95% CI 2.3–3.6), respectively. The prevalence of visual impairment ranged from 1.8% in the participant younger than 20 years of age to 28% in the subjects aged 60 and over (P<0.001). After matching for age, the prevalence of visual impairment and low vision was significantly higher in women. The most prevalent causes of visual impairment were uncorrected refractory error (54.5%) and cataract (17.6%). Conclusion: The prevalence of visual impairment was significantly higher in the rural population of this study when compared to previous reports from Iran. It seems that provision of therapeutic facilities like cataract surgery and availability of eyeglasses in villages can considerably reduce the prevalence of visual impairment. PMID:26258099

The Prevalence and Causes of Visaual Impairment and Blindness in a Rural Population in the North of Iran.

PubMed

Hashemi, Hassan; Rezvan, Farhad; Yekta, AbbasAli; Ostadimoghaddam, Hadi; Soroush, Sara; Dadbin, Nooshin; Khabazkhoob, Mehdi

2015-06-01

Visual impairment is a very important public health problem. In Iran, reports of visual impairment and blindness have been published from the urban population while the prevalence of visual impairment in the rural population has not been reported. The purpose of this study to determine the prevalence and causes of visual impairment, in a rural population in district of based on age and sex. In a cross-sectional population-based study, using random cluster sampling, 13 of the 83 villages of Khaf County in the north east of Iran were selected. Eye examinations were performed in a Mobile Eye Clinic (Nooravaran Salamat, 2011) and included optometric examinations such as measuring uncorrected and corrected visual acuity along with non-cycloplegic refraction. The prevalence of visual impairment, low vision, and blindness was 6.3% (95% CI 5.3-7.3), 3.4% (95% CI 2.6-4.1), and 3.0% (95% CI 2.3-3.6), respectively. The prevalence of visual impairment ranged from 1.8% in the participant younger than 20 years of age to 28% in the subjects aged 60 and over (P<0.001). After matching for age, the prevalence of visual impairment and low vision was significantly higher in women. The most prevalent causes of visual impairment were uncorrected refractory error (54.5%) and cataract (17.6%). The prevalence of visual impairment was significantly higher in the rural population of this study when compared to previous reports from Iran. It seems that provision of therapeutic facilities like cataract surgery and availability of eyeglasses in villages can considerably reduce the prevalence of visual impairment.

A new selective developmental deficit: Impaired object recognition with normal face recognition.

PubMed

Germine, Laura; Cashdollar, Nathan; Düzel, Emrah; Duchaine, Bradley

2011-05-01

Studies of developmental deficits in face recognition, or developmental prosopagnosia, have shown that individuals who have not suffered brain damage can show face recognition impairments coupled with normal object recognition (Duchaine and Nakayama, 2005; Duchaine et al., 2006; Nunn et al., 2001). However, no developmental cases with the opposite dissociation - normal face recognition with impaired object recognition - have been reported. The existence of a case of non-face developmental visual agnosia would indicate that the development of normal face recognition mechanisms does not rely on the development of normal object recognition mechanisms. To see whether a developmental variant of non-face visual object agnosia exists, we conducted a series of web-based object and face recognition tests to screen for individuals showing object recognition memory impairments but not face recognition impairments. Through this screening process, we identified AW, an otherwise normal 19-year-old female, who was then tested in the lab on face and object recognition tests. AW's performance was impaired in within-class visual recognition memory across six different visual categories (guns, horses, scenes, tools, doors, and cars). In contrast, she scored normally on seven tests of face recognition, tests of memory for two other object categories (houses and glasses), and tests of recall memory for visual shapes. Testing confirmed that her impairment was not related to a general deficit in lower-level perception, object perception, basic-level recognition, or memory. AW's results provide the first neuropsychological evidence that recognition memory for non-face visual object categories can be selectively impaired in individuals without brain damage or other memory impairment. These results indicate that the development of recognition memory for faces does not depend on intact object recognition memory and provide further evidence for category-specific dissociations in visual recognition. Copyright © 2010 Elsevier Srl. All rights reserved.

The Tehran Eye Study: research design and eye examination protocol

PubMed Central

Hashemi, Hassan; Fotouhi, Akbar; Mohammad, Kazem

2003-01-01

Background Visual impairment has a profound impact on society. The majority of visually impaired people live in developing countries, and since most disorders leading to visual impairment are preventable or curable, their control is a priority in these countries. Considering the complicated epidemiology of visual impairment and the wide variety of factors involved, region specific intervention strategies are required for every community. Therefore, providing appropriate data is one of the first steps in these communities, as it is in Iran. The objectives of this study are to describe the prevalence and causes of visual impairment in the population of Tehran city; the prevalence of refractive errors, lens opacity, ocular hypertension, and color blindness in this population, and also the familial aggregation of refractive errors, lens opacity, ocular hypertension, and color blindness within the study sample. Methods Design Through a population-based, cross-sectional study, a total of 5300 Tehran citizens will be selected from 160 clusters using a stratified cluster random sampling strategy. The eligible people will be enumerated through a door-to-door household survey in the selected clusters and will be invited. All participants will be transferred to a clinic for measurements of uncorrected, best corrected and presenting visual acuity; manifest, subjective and cycloplegic refraction; color vision test; Goldmann applanation tonometry; examination of the external eye, anterior segment, media, and fundus; and an interview about demographic characteristics and history of eye diseases, eye trauma, diabetes mellitus, high blood pressure, and ophthalmologic cares. The study design and eye examination protocol are described. Conclusion We expect that findings from the TES will show the status of visual problems and their causes in the community. This study can highlight the people who should be targeted by visual impairment prevention programs. PMID:12859794

The Tehran Eye Study: research design and eye examination protocol.

PubMed

Hashemi, Hassan; Fotouhi, Akbar; Mohammad, Kazem

2003-07-15

Visual impairment has a profound impact on society. The majority of visually impaired people live in developing countries, and since most disorders leading to visual impairment are preventable or curable, their control is a priority in these countries. Considering the complicated epidemiology of visual impairment and the wide variety of factors involved, region specific intervention strategies are required for every community. Therefore, providing appropriate data is one of the first steps in these communities, as it is in Iran. The objectives of this study are to describe the prevalence and causes of visual impairment in the population of Tehran city; the prevalence of refractive errors, lens opacity, ocular hypertension, and color blindness in this population, and also the familial aggregation of refractive errors, lens opacity, ocular hypertension, and color blindness within the study sample. Through a population-based, cross-sectional study, a total of 5300 Tehran citizens will be selected from 160 clusters using a stratified cluster random sampling strategy. The eligible people will be enumerated through a door-to-door household survey in the selected clusters and will be invited. All participants will be transferred to a clinic for measurements of uncorrected, best corrected and presenting visual acuity; manifest, subjective and cycloplegic refraction; color vision test; Goldmann applanation tonometry; examination of the external eye, anterior segment, media, and fundus; and an interview about demographic characteristics and history of eye diseases, eye trauma, diabetes mellitus, high blood pressure, and ophthalmologic cares. The study design and eye examination protocol are described. We expect that findings from the TES will show the status of visual problems and their causes in the community. This study can highlight the people who should be targeted by visual impairment prevention programs.

Visual selective attention in amnestic mild cognitive impairment.

PubMed

McLaughlin, Paula M; Anderson, Nicole D; Rich, Jill B; Chertkow, Howard; Murtha, Susan J E

2014-11-01

Subtle deficits in visual selective attention have been found in amnestic mild cognitive impairment (aMCI). However, few studies have explored performance on visual search paradigms or the Simon task, which are known to be sensitive to disease severity in Alzheimer's patients. Furthermore, there is limited research investigating how deficiencies can be ameliorated with exogenous support (auditory cues). Sixteen individuals with aMCI and 14 control participants completed 3 experimental tasks that varied in demand and cue availability: visual search-alerting, visual search-orienting, and Simon task. Visual selective attention was influenced by aMCI, auditory cues, and task characteristics. Visual search abilities were relatively consistent across groups. The aMCI participants were impaired on the Simon task when working memory was required, but conflict resolution was similar to controls. Spatially informative orienting cues improved response times, whereas spatially neutral alerting cues did not influence performance. Finally, spatially informative auditory cues benefited the aMCI group more than controls in the visual search task, specifically at the largest array size where orienting demands were greatest. These findings suggest that individuals with aMCI have working memory deficits and subtle deficiencies in orienting attention and rely on exogenous information to guide attention. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A population-based survey of visual impairment and its correlates in Mahabubnagar district, Telangana State, India.

PubMed

Mactaggart, Islay; Polack, Sarah; Murthy, Gvs; Kuper, Hannah

2018-06-01

To estimate the prevalence and correlates of visual impairment in Mahabubnagar district, Telangana, India. Fifty-one clusters of 80 people (all ages) were sampled with probability proportionate to size. Households within clusters were selected through the compact segment sampling. Visual acuity (VA) was measured with a tumbling "E" chart. An Ophthalmic Assistant or Vision Technician examined people with VA<6/12 in either eye. Other impairments (hearing, physical) were clinically assessed and self-reported functional difficulties measured using the Washington Group Extended Set. People with visual impairment and age-sex matched controls with normal vision were interviewed about poverty, employment and education. 4,125 people were enumerated and 3,574 screened (86.6%). The prevalence of visual impairment (VA<6/12) was 8.0% (95% CI = 6.9-9.4%) and blindness was 0.4% (0.2-0.9%), and both increased rapidly with age. Uncorrected refractive error was the leading cause of visual impairment, and cataract the leading cause of blindness. Cataract surgical coverage (proportion of all cataracts that had received surgery) was relatively low (41% of people at VA<6/60), while the post-surgery outcomes were good (81% of operated eyes had presenting VA≥6/18). Among the 287 people with visual impairment, 15% had a moderate/severe physical impairment or epilepsy and 25% had a moderate/severe hearing impairment. Self-reported difficulties in vision were relatively closely related to visual acuity. People with visual impairment were more likely to be in the poorest quartile (OR = 1.9, 95% CI = 1.0-3.4) or unemployed (5.0, 2.2-10.0), compared to controls. Visual impairment was common in Mahabubnagar district, was mostly avoidable, and was correlated with poverty markers.

Prevalence and causes of blindness and visual impairment among school children in south-western Nigeria.

PubMed

Ajaiyeoba, A I; Isawumi, M A; Adeoye, A O; Oluleye, T S

2005-01-01

The aim of the study was to assess the prevalence and identify the causes of blindness and visual impairment in school children of Ilesa-East Local Government Area of Osun State, Nigeria. A total of 1144 school children in primary and secondary schools were selected using a 2-stage random sampling method and examined to determine the prevalence and causes of blindness and visual impairment. A total of 17 (1.48%) children were blind or visually impaired. These comprised of 11 (0.96%) children who were visually impaired and 4 (0.3%) who were severely visually impaired. Only 2 (0.15%) school children were blind. The causes of visual impairment were refractive error 10 (0.87%) and immature cataract 1 (0.08%), causes of severe visual impairment included corneal opacities 2 (0.2%), amblyopia leading to squint 1 (0.08%) and 1 cataract 1 (0.08%). The causes of blindness in school children were corneal scars presumed to be due to vitamin A deficiency 1 (0.08%) and keratoconus 1 (0.08%). Causes of blindness and visual impairment in children attending regular schools in Nigeria were treatable. Prevention, early recognition and prompt treatment of these diseases by regular screening of school children would definitely reduce unnecessary visual handicap in Nigerian school children so that they can attain their full potential in the course of their education. Also, information from this study is relevant for the purpose of planning eye care programmes for the prevention of blindness in Nigerian school children. This will go a long way in the prevention of unnecessary blindness and visual impairment in school children.

Visual attention in posterior stroke and relations to alexia.

PubMed

Petersen, A; Vangkilde, S; Fabricius, C; Iversen, H K; Delfi, T S; Starrfelt, R

2016-11-01

Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere, while attentional effects of more posterior lesions are less clear. Commonly, such deficits are investigated in relation to specific syndromes like visual agnosia or pure alexia. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. In addition, the relationship between these attentional parameters and single word reading is investigated, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Eight patients with unilateral PCA strokes (four left hemisphere, four right hemisphere) were selected on the basis of lesion location, rather than the presence of any visual symptoms. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific measurements of processing speed and apprehension span. All patients showed reductions in visual span contralateral to the lesion site, and four patients showed bilateral reductions in visual span despite unilateral lesions (2L; 2R). Six patients showed selective deficits in visual span, though processing speed was unaffected in the same field (ipsi- or contralesionally). Only patients with right hemifield reductions in visual span were impaired in reading, and this could follow either right or left lateralized stroke and was irrespective of visual field impairments. In conclusion, visual span may be affected bilaterally by unilateral PCA-lesions. Reductions in visual span may also be confined to one hemifield, and may be affected in spite of preserved visual processing speed. Furthermore, reduced span in the right visual field seems to be related to reading impairment in this group, regardless of lesion lateralization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prevalence and factors associated with childhood visual impairment in Ethiopia

PubMed Central

Bezabih, Lidiya; Abebe, Tilaye Workneh; Fite, Robera Olana

2017-01-01

Background Visual impairment is a significant loss of vision. It has an impact on the prosperity of different countries. It has been difficult to plan preventive measures against visual impairment due to the scarcity of data about the extent of the problem. Objectives The study was aimed at assessing the prevalence and identifying factors associated with visual impairment among school-age children in Ethiopia. Materials and methods A cross-sectional study design was used in four randomly selected schools found in Addis Ababa from May 15 to June 14, 2016. A total of 804 school-age students were selected using the simple random sampling method. Bivariable logistic regression and multivariable logistic regression were conducted. A p-value <0.05 was taken as a significant association. Results A total of 718 students participated in the study, obtaining a response rate of 89.3%. In all, 7.24% of school-age children were visually impaired, of whom 3.9% had low vision and 3.34% had severe visual impairment. Factors associated with visual impairment were being female (adjusted odds ratio [AOR], 2.28; 95% confidence interval [CI], 1.06–3.50), being in the age group of 10–13 years (AOR, 2.94; 95% CI, 1.36–6.22), being in the age group of 14–18 years (AOR, 4.06; 95% CI, 2.17–11.95), being a private school student (AOR, 2.61; 95% CI, 1.81–4.41), watching television for 2–4 hours/day (AOR, 3.56; 95% CI, 1.37–7.34), watching television at <1 m (AOR, 7.65; 95% CI, 2.59–34.61), watching television at 1–2 m (AOR, 6.89; 95% CI, 1.74–25.27), mobile exposure for 2–4 hours/day (AOR, 2.61; 95% CI, 1.35–4.58), mobile exposure for >4 hours/day (AOR, 3.05; 95% CI, 1.41–9.18), medical visit while experiencing symptoms (AOR, 11.32; 95% CI, 1.80–82.25) and no medical visit experience (AOR, 3.84; 95% CI, 0.46–31.76). Conclusion The majority of the visually impaired school-age children had low vision. Sex, age, school type, television exposure duration, the distance of television exposure, mobile exposure and medical visit were factors associated with visual impairment. Increasing community awareness about early detection of visual impairment and providing affordable eye health service may decrease the prevalence of visual impairment. PMID:29184383

Assessment of Psychological and Psycho-physiological Problems Among Visually Impaired Adolescents

PubMed Central

Bhuvaneswari, Mohanraj; Immanuel Selvaraj, Chinnadurai; Selvaraj, Balakrishnan; Srinivasan, Thiruvengadam

2016-01-01

Background: Visual impairment tends to evoke more discomfiture than any other disability. Primarily, the biggest issue may be that blindness is visible. Furthermore, visual impairment develops serious medical, psychological, social and economic problems. Objectives: The focus of the current study was to investigate the psychological and psycho physiological problems of visually impaired adolescent students. Patients and Methods: Purposive sampling was adopted to select 150 visually impaired students (71 males and 72 females) from five schools in Coimbatore city of the Tamil Nadu state, India. Anxiety, frustration, aggression and social and personal adjustment levels of the visually impaired students were measured in this study using Taylor’s manifest anxiety scale, frustration test, aggression scale and the adolescent adjustment inventory, respectively. Results: Anxiety (χ2 = 185.66, P = 0 at P < 0.01), frustration (χ2 = 167.23, P = 0 at P < 0.01) and aggression (χ2 = 57.66, P = 0 at P < 0.01) were significantly related to adjustment among visually impaired students. The adjustment score had a significant positive correlation with anxiety (r = 0.919, P = 0 at P < 0.01), frustration (r = 0.887, P = 0 at P < 0.01) and aggression levels (r = 0.664, P = 0 at P < 0.01), anxiety was significantly correlated with frustration (r = 0. 961, P = 0 at P < 0.01) and aggression levels (r = 0.727, P < 0.01) and frustration was significantly correlated with aggression level (r = 0. 637, P = 0 at P < 0.01) of visually impaired adolescents. There was a positive relationship between psycho-physiological disorders and anxiety frustration, aggression and adjustment among visually impaired students. Conclusions: Visually impaired students exhibited significant levels of psychological and psycho-physiological problems. PMID:27284280

Investigation of Priority Needs in Terms of Museum Service Accessibility for Visually Impaired Visitors

ERIC Educational Resources Information Center

Handa, Kozue; Dairoku, Hitoshi; Toriyama, Yoshiko

2010-01-01

This study investigates the priority needs of museum service accessibility for visually impaired visitors. For this purpose, conjoint analysis was utilized. Four conjoint attributes of museum services were selected: A--facilities for wayfinding; B--exhibitions and collections including objects for touching, hearing, smelling, etc.; C--information…

Assistive Device Use in Visually Impaired Older Adults: Role of Control Beliefs

ERIC Educational Resources Information Center

Becker, Stefanie; Wahl, Hans-Werner; Schilling, Oliver; Burmedi, David

2005-01-01

Purpose: We investigate whether psychological control, conceptually framed within the life-span theory of control by Heckhausen and Schulz, drives assistive device use in visually impaired elders. In particular, we expect the two primary control modes differentiated in the life-span theory of control (i.e., selective primary and compensatory…

The Association of Visual Impairment With Clinical Outcomes in Hemodialysis Patients

PubMed Central

Hong, Yu Ah; Kim, Suk Young; Kim, Su-Hyun; Kim, Young Ok; Jin, Dong Chan; Song, Ho Chul; Choi, Euy Jin; Kim, Yong-Lim; Kim, Yon-Su; Kang, Shin-Wook; Kim, Nam-Ho; Yang, Chul Woo; Kim, Yong Kyun

2016-01-01

Abstract Visual impairment limits people's ability to perform daily tasks and affects their quality of life. We evaluated the impact of visual impairment on clinical outcomes in hemodialysis (HD) patients. HD patients were selected from the Clinical Research Center registry a prospective cohort study on dialysis patients in Korea. Visual impairment was defined as difficulty in daily life due to decreased visual acuity or blindness. The primary outcome was all-cause mortality and the secondary outcomes were cardiovascular and infection-related hospitalization. A total of 3250 patients were included. Seven hundred thirty (22.5%) of the enrolled patients had visual impairment. The median follow-up period was 30 months. The Kaplan–Meier curve and log-rank test showed that all-cause mortality rates (P < 0.001) as well as cardiovascular and infection-related hospitalization rates (P < 0.001 and P < 0.001) were significantly higher in patients with visual impairment than in patients without visual impairment. In the multivariable analysis, visual impairment had significant predictive power for all-cause mortality (Hazard ratio [HR], 1.77, 95% confidence interval [CI], 1.21–2.61, P = 0.004) and cardiovascular hospitalization (HR 1.45 [1.00–1.90], P = 0.008) after adjusting for confounding variables. Of these 3250 patients, 634 patients from each group were matched by propensity scores. In the propensity score matched analysis, patients with visual impairment had independently significant associations with increased all-cause mortality (HR 1.69 [1.12–2.54], P = 0.01) and cardiovascular hospitalization (HR 1.48 [1.08–2.02], P = 0.01) compared with patients without visual impairment after adjustment for confounding variables. Our data demonstrated that visual impairment was an independent risk factor for clinical adverse outcomes in HD patients. PMID:27175661

Evidence-based guidelines on the referral of visually impaired persons to low vision services.

PubMed

De Boer, M R; Langelaan, M; Jansonius, N M; Van Rens, G H M B

2005-01-01

One to two percent of the population in the Western world is visually impaired or blind. For most of these people there is no curative therapy. Therefore, the Dutch Ophthalmic Society has taken the initiative to develop an evidence-based guideline for the referral of visually impaired persons to low vision services. A systematic literature search was performed in the Embase (1991-2001) and Medline (1966-2003) databases. Literature was searched for definitions of visual impairment, for physician-patient communication, and for outcome of interventions for visually impaired persons. Results of the articles that were selected were summarized and rated according to the level of evidence. Other considerations such as the current organization of rehabilitation for visually impaired persons in the Netherlands were also taken into account. The World Health Organization criteria were slightly adapted in order to include all people who experience problems with reading and other daily life activities due to visual impairment. A large number of recommendations were devised. Among these is that the complete diagnosis should be communicated to the patient and that a second appointment should be offered in which the diagnosis and potential treatment options are discussed again. Another recommendation is that in general visually impaired adults eligible for referral should be referred for the provision of low vision aids and that patients with complex problems or extensive rehabilitative demand should be referred to a rehabilitation center. This article presents a summary of the first European evidence-based guideline for the referral of visually impaired persons.

The Prevalence of Visual Acuity Impairment among School Children at Arada Subcity Primary Schools in Addis Ababa, Ethiopia.

PubMed

Darge, Haile Fentahun; Shibru, Getahun; Mulugeta, Abiy; Dagnachew, Yinebeb Mezgebu

2017-01-01

Visual impairment and blindness are major public health problems in developing countries where there is no enough health-care service. To determine the prevalence of visual impairment among school children. A school-based cross-sectional study was conducted between 15 June 2015 and 30 November 2015 at Arada subcity primary schools, Addis Ababa, Ethiopia. Two schools were selected randomly, and 378 students were screened from grades 1 to 8 using systematic random sampling method. Snellen chart was used for visual acuity test. Students who had visual acuity of ≤6/12 were further examined by an ophthalmologist to diagnose the reason for low vision. Data was analyzed using SPSS version 20. A total of 378 students were screened, and 192 (50.8%) were females and the remaining 186 (49.2%) were males. The prevalence of visual impairment (VA) of ≤6/12 on either eye was 5.8%, VA < 6/18 on either eye was 1.1%, and VA < 6/18 on the better eye was 0.53%. In this study, color blindness [OR: 19.65, 95% CI (6.01-64.33)] was significantly associated with visual acuity impairment. The prevalence of visual impairment among school children in the study area was 5.8% and school screening is recommended.

The Selection of Tangible Symbols by Educators of Students with Visual Impairments and Additional Disabilities

ERIC Educational Resources Information Center

Trief, Ellen; Bruce, Susan M.; Cascella, Paul W.

2010-01-01

Tangible symbols are objects or partial objects that can be physically manipulated and that share a perceptual relationship with what they represent, known as the referent. They make fewer demands on memory and representational ability, making them an appropriate expressive form of communication for individuals with visual impairments and…

An Assessment of the Tinder Mobile Dating Application for Individuals Who Are Visually Impaired

ERIC Educational Resources Information Center

Kapperman, Gaylen; Kelly, Stacy M.; Kilmer, Kylie; Smith, Thomas J.

2017-01-01

People with visual impairments (that is, those who are blind or have low vision) have a disadvantage in the process of being selected as a romantic partner. It is further underscored that these difficulties with dating and fitting in among sighted individuals extend beyond formative years into adulthood (Sacks & Wolffe, 2006). Thus, the…

Effect of Selected Balance Exercises on the Dynamic Balance of Children with Visual Impairments

ERIC Educational Resources Information Center

Jazi, Shirin Davarpanah; Purrajabi, Fatemeh; Movahedi, Ahmadreza; Jalali, Shahin

2012-01-01

Introduction: Maintaining balance while walking is of utmost importance for individuals with visual impairments because deficits in dynamic balance have been associated with a high risk of falling. Thus, the primary aim of the study presented here was to determine whether balance training effects the dynamic balance of children with visual…

Experiences of Students with Visual Impairments in Adoption of Digital Talking Textbooks: An Interpretative Phenomenological Analysis

ERIC Educational Resources Information Center

Hussin, Ahamad

2013-01-01

Assistive technology devices have become essential tools for students with visual impairments. In 2009, the Malaysian Ministry of Education introduced Digital Talking Textbooks (DTTs) for selected subjects to facilitate learning. The purpose of this qualitative study was to explore, describe, and interpret the experiences of students with visual…

Prevalence and risk factors of visual impairment and blindness in Korea: the Fourth Korea National Health and Nutrition Examination Survey in 2008-2010.

PubMed

Rim, Tyler H T; Nam, Jae S; Choi, Moonjung; Lee, Sung C; Lee, Christopher S

2014-06-01

To describe the age, gender specific prevalence and risk factors of visual impairment and blindness in Korea. From 2008 to 2010, a total 14 924 randomly selected national representative participants of the Korea National Health and Nutrition Examination Survey underwent additional ophthalmologic examinations by the Korean Ophthalmologic Society. Best Corrected Distance Visual Acuity was measured using an international standard vision chart based on Snellen scale (Jin's vision chart). Independent risk factors for visual impairment were investigated using multivariate logistic regression analysis. The overall prevalence of visual impairment (≤20/40) of adults 40 years and older was 4.1% (95% CI, 3.6-4.6) based on the better seeing eye. The overall prevalence of blindness (≤20/200) for adults 40 years and older was 0.2% (95% CI, 0.1-0.3). Risk indicators of visual impairment were increasing age, low education status, living in rural area, being unemployed, being without spouse and the absence of private health insurance. The visually impaired were more likely to have eye diseases compared with the normal subjects, and they were less likely to utilize eye care. The prevalence of visual impairment was demonstrated to be higher while that of blindness was similar to previous population studies in Asia or U.S. Sociodemographic disparities are present in the prevalence of visual impairment and more targeted efforts are needed to promote vision screening in high risk groups. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Active listening impairs visual perception and selectivity: an ERP study of auditory dual-task costs on visual attention.

PubMed

Gherri, Elena; Eimer, Martin

2011-04-01

The ability to drive safely is disrupted by cell phone conversations, and this has been attributed to a diversion of attention from the visual environment. We employed behavioral and ERP measures to study whether the attentive processing of spoken messages is, in itself, sufficient to produce visual-attentional deficits. Participants searched for visual targets defined by a unique feature (Experiment 1) or feature conjunction (Experiment 2), and simultaneously listened to narrated text passages that had to be recalled later (encoding condition), or heard backward-played speech sounds that could be ignored (control condition). Responses to targets were slower in the encoding condition, and ERPs revealed that the visual processing of search arrays and the attentional selection of target stimuli were less efficient in the encoding relative to the control condition. Results demonstrate that the attentional processing of visual information is impaired when concurrent spoken messages are encoded and maintained, in line with cross-modal links in selective attention, but inconsistent with the view that attentional resources are modality-specific. The distraction of visual attention by active listening could contribute to the adverse effects of cell phone use on driving performance.

Visual-perceptual impairment in children with cerebral palsy: a systematic review.

PubMed

Ego, Anne; Lidzba, Karen; Brovedani, Paola; Belmonti, Vittorio; Gonzalez-Monge, Sibylle; Boudia, Baya; Ritz, Annie; Cans, Christine

2015-04-01

Visual perception is one of the cognitive functions often impaired in children with cerebral palsy (CP). The aim of this systematic literature review was to assess the frequency of visual-perceptual impairment (VPI) and its relationship with patient characteristics. Eligible studies were relevant papers assessing visual perception with five common standardized assessment instruments in children with CP published from January 1990 to August 2011. Of the 84 studies selected, 15 were retained. In children with CP, the proportion of VPI ranged from 40% to 50% and the mean visual perception quotient from 70 to 90. None of the studies reported a significant influence of CP subtype, IQ level, side of motor impairment, neuro-ophthalmological outcomes, or seizures. The severity of neuroradiological lesions seemed associated with VPI. The influence of prematurity was controversial, but a lower gestational age was more often associated with lower visual motor skills than with decreased visual-perceptual abilities. The impairment of visual perception in children with CP should be considered a core disorder within the CP syndrome. Further research, including a more systematic approach to neuropsychological testing, is needed to explore the specific impact of CP subgroups and of neuroradiological features on visual-perceptual development. © 2015 The Authors. Developmental Medicine & Child Neurology © 2015 Mac Keith Press.

An investigation of ultramarathon-associated visual impairment.

PubMed

Høeg, Tracy B; Corrigan, Genevieve K; Hoffman, Martin D

2015-06-01

The purpose of this study was to investigate the characteristics under which ultramarathon-associated visual impairment occurs and to seek to identify its physiological basis and risk factors. Through an online questionnaire, distributed worldwide, we obtained information from 173 self-identified ultramarathon runners who had experienced visual impairment during an ultramarathon. We attempted to characterize this vision impairment-its symptoms, duration, and the conditions under which it occurs. Select characteristics were compared with a reference group of 412 registrants of the 161-km Western States Endurance Run. Ultramarathon-associated visual impairment was typically characterized as painless clouding of vision that resolved either during (13.5%) or after racing within a median of 3.5 hours (range 0 to 48 hours) upon cessation of running. The mean (±SD) distance at which vision impairment occurred was 73±40 km, and the 161-km distance was the most frequent race distance (46.8%) in which visual impairment occurred. Visual impairment was often recurrent, with respondents reporting having it develop during a median of 2 races. Respondents with a history of refractive surgery had more episodes than those without such history (median 3.5 vs 2 episodes, P=.010). Compared with the reference group, runners with visual impairment were nearly twice as likely (23.7% vs 12.1%, P<.001) to have had refractive surgery. Ultramarathon-associated visual impairment typically presents as a painless clouding of vision that is self-limited but tends to recur in certain runners. Risk appears higher among those with a history of refractive surgery, which is relevant for ultramarathon runners who are considering, or who have a history of, refractive surgery. Published by Elsevier Inc.

Effects of lorazepam on visual perceptual abilities.

PubMed

Pompéia, S; Pradella-Hallinan, M; Manzano, G M; Bueno, O F A

2008-04-01

To evaluate the effects of an acute dose of the benzodiazepine (BZ) lorazepam in young healthy volunteers on five distinguishable visual perception abilities determined by previous factor-analytic studies. This was a double-blind, cross-over design study of acute oral doses of lorazepam (2 mg) and placebo in young healthy volunteers. We focused on a set of paper-and-pencil tests of visual perceptual abilities that load on five correlated but distinguishable factors (Spatial Visualization, Spatial Relations, Perceptual Speed, Closure Speed, and Closure Flexibility). Some other tests (DSST, immediate and delayed recall of prose; measures of subjective mood alterations) were used to control for the classic BZ-induced effects. Lorazepam impaired performance in the DSST and delayed recall of prose, increased subjective sedation and impaired tasks of all abilities except Spatial Visualization and Closure Speed. Only impairment in Perceptual Speed (Identical Pictures task) and delayed recall of prose were not explained by sedation. Acute administration of lorazepam, in a dose that impaired episodic memory, selectively affected different visual perceptual abilities before and after controlling for sedation. Central executive demands and sedation did not account for results, so impairment in the Identical Pictures task may be attributed to lorazepam's visual processing alterations. 2008 John Wiley & Sons, Ltd.

The prevalence of visual impairment in school children of upper-middle socioeconomic status in Kathmandu.

PubMed

Sapkota, Yuddha D; Adhikari, Bishwa Nath; Pokharel, Gopal P; Poudyal, Bimal K; Ellwein, Leon B

2008-01-01

Assess visual impairment in school children of upper-middle socioeconomic status in Kathmandu for comparison with rural Jhapa District. Random selection of classes from secondary private schools in Kathmandu was used to identify the study sample. Children in 130 classes at 43 schools were enumerated using school records and examined between January-May 2006. Examinations included visual acuity testing, ocular motility evaluation, cycloplegic refraction, and examination of the external eye, anterior segment, media, and fundus. The principal cause was determined for eyes with uncorrected visual acuity < or = 20/40. A total of 4,501 children in grades 5-9 were enumerated; 4282 (95.1%) were examined. The prevalence of uncorrected, presenting, and best-corrected visual impairment (< or = 20/40) in the better eye was 18.6%, 9.1%, and 0.86%, respectively. Refractive error was a cause in 93.3% of children with uncorrected visual impairment, amblyopia 1.8%, retinal disorders 1.3%, other causes 0.3%, and unexplained causes 4.4%. Among children correctable in at least one eye, 46.3% presented without the necessary spectacles. Visual impairment with myopia (-0.50 diopters) ranged from 10.9% in 10 year-olds to 27.3% in 15 year-olds, compared to 0.5%-3.0% in rural Jhapa District. Myopic visual impairment was associated with grade level, female gender, parental education, parental spectacle usage, and Mongol ethnicity. Visual impairment with myopia among upper-middle socioeconomic school children in Kathmandu is higher than that in rural Nepal, and a public health problem because nearly half are without corrective spectacles. Effective strategies are needed to eliminate this easily treatable cause of visual impairment.

Low Vision Aids for Visually Impaired Children

ERIC Educational Resources Information Center

Schurink, J.; Cox, R. F. A.; Cillessen, A. H. N.; van Rens, G. H. M. B.; Boonstra, F. N.

2011-01-01

It is a widely accepted belief in clinical practice that children with a visual impairment can profit from the use of a low vision aid (LVA). However, we found a considerable gap in our scientific understanding of LVA use, particularly in young children. This is the reason for the analysis presented in this paper. A selected overview of LVA use in…

A Note on Some Problems in the Testing of Personality Characteristics in Children with Visual Impairment

ERIC Educational Resources Information Center

Tobin, Michael; Hill, Eileen

2010-01-01

An examination is made of the value of using published personality tests with young blind and partially sighted children. Based on data gathered during a longitudinal investigation into the educational and psychological development of a group of 120 visually impaired learners, the authors conclude that their own selection of a test instrument…

The Impact of the Perspectives of Teachers and Parents on the Literacy Media Selections for Independent Study of Students Who Are Visually Impaired

ERIC Educational Resources Information Center

Argyropoulos, Vassilios S.; Sideridis, Georgios D.; Katsoulis, Philippos

2008-01-01

This study explored the choices of literacy media for independent study of students with visual impairments. The predictors that were taken into account were teachers' use of technology, experience in teaching, and mastery of braille and the knowledge of braille of students, parents, and close friends.

Teachers' Methodologies and Sources of Information on HIV/AIDS for Students with Visual Impairments in Selected Residential and Integrated Schools in Ghana

ERIC Educational Resources Information Center

Hayford, Samuel K.; Ocansey, Frederick

2017-01-01

This study reports part of a national survey on sources of information, education and communication materials on HIV/AIDS available to students with visual impairments in residential, segregated, and integrated schools in Ghana. A multi-staged stratified random sampling procedure and a purposive and simple random sampling approach, where…

[Prevalence of blindness and moderate and severe visual impairment among adults aged 50 years or above in Shuangcheng City of Heilongjiang Province: the China Nine-Province Survey].

PubMed

Zhang, Liqiong; Cui, Hao; Zhao, Jialiang; Ellwein, Leon B; Li, Zhijian; Li, Mingsheng; Yu, Nannan; Wang, Yu; Gao, Xuecheng

2014-03-01

To investigate the prevalence of blindness and moderate and severe visual impairment among adults aged 50 years or above in Shuangcheng City of Heilongjiang Province, China. It was a population-based cross-section study. Geographically defined cluster sampling was used in randomly selecting 5 841 individuals aged 50 years or above in 28 basic sample units in Shuangcheng City from September to December 2006. The survey was preceded by a pilot study where operational methods were refined and quality assurance evaluation was carried out. All participants were enumerated through village registers followed door-to-door visits.Eligible individuals were invited to receive visual acuity measurement and eye examination. Statistical analyses were performed using Stata/SE Statistical Software, release 9.0. Chi-square test was used to investigate the association of age, gender and education with presenting and best corrected visual acuity. Five thousands four hundreds and eighty-one individuals were enumerated and 5 047 persons were examined, the response rate was 92.08%. Based on the criteria of World Health Organization visual impairment classification in 1973, the prevalence of blindness and moderate and severe visual impairment defined as best corrected visual acuity was 1.72% (87/5 047) and 4.69% (237/5 047) respectively. The prevalence of blindness and moderate and severe visual impairment defined as presenting visual acuity was 1.90% (96/5 047) and 7.23% (365/5 047) respectively. The prevalence of blindness and moderate and severe visual impairment was higher in aged (trend χ(2)=674.44, P < 0.01), female (χ(2)=39.61, P < 0.01) and illiterate (trend χ(2)=142.82, P < 0.01) persons. Cataract (52.70%) was still the first leading cause of blindness and visual impairment. The percentage of the retinal diseases, including age-related macular degeneration, high myopic retinopathy and diabetic retinopathy was 11.31% among the eyes with blindness and moderate and severe visual impairment. Un-corrected refractive error(13.38%) also was the main cause of visual impairment. The prevalence of blindness and moderate and severe visual impairment in Shuangcheng City is relatively higher in China Nine Province Survey. Cataract, retinal diseases and un-corrected refractive error are the main causes of the blindness and moderate and severe visual impairment.

A Componential Analysis of Visual Attention in Children With ADHD.

PubMed

McAvinue, Laura P; Vangkilde, Signe; Johnson, Katherine A; Habekost, Thomas; Kyllingsbæk, Søren; Bundesen, Claus; Robertson, Ian H

2015-10-01

Inattentive behaviour is a defining characteristic of ADHD. Researchers have wondered about the nature of the attentional deficit underlying these symptoms. The primary purpose of the current study was to examine this attentional deficit using a novel paradigm based upon the Theory of Visual Attention (TVA). The TVA paradigm enabled a componential analysis of visual attention through the use of a mathematical model to estimate parameters relating to attentional selectivity and capacity. Children's ability to sustain attention was also assessed using the Sustained Attention to Response Task. The sample included a comparison between 25 children with ADHD and 25 control children aged 9-13. Children with ADHD had significantly impaired sustained attention and visual processing speed but intact attentional selectivity, perceptual threshold and visual short-term memory capacity. The results of this study lend support to the notion of differential impairment of attentional functions in children with ADHD. © 2012 SAGE Publications.

Alcohol consumption and visual impairment in a rural Northern Chinese population.

PubMed

Li, Zhijian; Xu, Keke; Wu, Shubin; Sun, Ying; Song, Zhen; Jin, Di; Liu, Ping

2014-12-01

To investigate alcohol drinking status and the association between drinking patterns and visual impairment in an adult population in northern China. Cluster sampling was used to select samples. The protocol consisted of an interview, pilot study, visual acuity (VA) testing and a clinical examination. Visual impairment was defined as presenting VA worse than 20/60 in any eye. Drinking patterns included drinking quantity (standard drinks per week) and frequency (drinking days in the past week). Information on alcohol consumption was obtained from 8445 subjects, 963 (11.4%) of whom reported consuming alcohol. In multivariate analysis, alcohol consumption was significantly associated with older age (p < 0.001), male sex (p < 0.001), and higher education level (p < 0.01). Heavy intake (>14 drinks/week) was associated with higher odds of visual impairment. However, moderate intake (>1-14 drinks/week) was significantly associated with lower odds (adjusted odds ratio, OR, 0.7, 95% confidence interval, CI, 0.5-1.0) of visual impairment (p = 0.03). Higher drinking frequency was significantly associated with higher odds of visual impairment. Multivariate analysis showed that older age, male sex, and higher education level were associated with visual impairment among current drinkers. Age- and sex-adjusted ORs for the association of cataract and alcohol intake showed that higher alcohol consumption was not significantly associated with an increased prevalence of cataract (OR 1.2, 95% CI 0.4-3.6), whereas light and moderate alcohol consumption appeared to reduce incidence of cataract. Drinking patterns were associated with visual impairment. Heavy intake had negative effects on distance vision; meanwhile, moderate intake had a positive effect on distance vision.

Deficits of spatial and task-related attentional selection in mild cognitive impairment and Alzheimer's disease.

PubMed

Redel, P; Bublak, P; Sorg, C; Kurz, A; Förstl, H; Müller, H J; Schneider, W X; Perneczky, R; Finke, K

2012-01-01

Visual selective attention was assessed with a partial-report task in patients with probable Alzheimer's disease (AD), amnestic mild cognitive impairment (MCI), and healthy elderly controls. Based on Bundesen's "theory of visual attention" (TVA), two parameters were derived: top-down control of attentional selection, representing task-related attentional weighting for prioritizing relevant visual objects, and spatial distribution of attentional weights across the left and the right hemifield. Compared with controls, MCI patients showed significantly reduced top-down controlled selection, which was further deteriorated in AD subjects. Moreover, attentional weighting was significantly unbalanced across hemifields in MCI and tended to be more lateralized in AD. Across MCI and AD patients, carriers of the apolipoprotein E ε4 allele (ApoE4) displayed a leftward spatial bias, which was the more pronounced the younger the ApoE4-positive patients and the earlier disease onset. These results indicate that impaired top-down control may be linked to early dysfunction of fronto-parietal networks. An early temporo-parietal interhemispheric asymmetry might cause a pathological spatial bias which is associated with ApoE4 genotype and may therefore function as early cognitive marker of upcoming AD. Copyright © 2012 Elsevier Inc. All rights reserved.

The Effect of a Training Programme in Creativity on Developing the Creative Abilities among Children with Visual Impairment

ERIC Educational Resources Information Center

Al-Dababneh, Kholoud A.; al-Masa'deh, Mu'tasem M.; Oliemat, Enass M.

2015-01-01

This study aims to investigate the effects of a training programme in creativity on developing creative abilities among 9-10-year-old children with visual impairment in Jordan. The study sample consisted of 41 students from fourth and fifth grades, who were randomly selected and divided into two experimental groups and two control groups. To…

How Early Intervention Services Became Available in South Florida: A Story for the Silver Screen?

ERIC Educational Resources Information Center

Erin, Jane N.

2013-01-01

Have you ever imagined yourself as a movie producer who could tell the stories of the remarkable successes in the field of visual impairment and blindness? With the right buildup music and the careful selection of a popular actor or a promising young ingenue (ideally, someone with a visual impairment), any one of these real-life stories could be a…

Prevalence and Causes of Visual Impairment and Blindness among Cocoa Farmers in Ghana.

PubMed

Boadi-Kusi, Samuel Bert; Hansraj, Rekha; Mashige, Khathutshelo Percy; Osafo-Kwaako, Alfred; Ilechie, Alex Azuka; Abokyi, Samuel

2017-02-01

To determine the prevalence and causes of visual impairment and blindness among cocoa farmers in Ghana in order to formulate early intervention strategies. A cross-sectional study using multistage random sampling from four cocoa growing districts in Ghana was conducted from November 2013 to April 2014. A total of 512 cocoa farmers aged 40 years and older were interviewed and examined. The brief interview questionnaire was administered to elicit information on the demographics and socioeconomic details of participants. The examination included assessment of visual acuity (VA), retinoscopy, subjective refraction, direct ophthalmoscopy, slit-lamp biomicroscopy and intraocular pressure (IOP). For quality assurance, a random sample of cocoa farmers were selected and re-examined independently. Moderate to severe visual impairment (VA <6/18 to 3/60 in the better-seeing eye) was present in 89 participants (17.4%) and 27 (5.3%) were blind (presenting VA <3/60 in the better eye) defined using presenting VA. The main causes of visual impairment were cataract (45, 38.8%), uncorrected refractive error (42, 36.2%), posterior segment disorders (15, 12.9%), and corneal opacity (11, 9.5%). The prevalence of visual impairment and blindness among cocoa farmers in Ghana is relatively high. The major causes of visual impairment and blindness are largely preventable or treatable, indicating the need for early eye care service interventions.

A Systematic Review of the Literature on Parenting of Young Children with Visual Impairments and the Adaptions for Video-Feedback Intervention to Promote Positive Parenting (VIPP).

PubMed

van den Broek, Ellen G C; van Eijden, Ans J P M; Overbeek, Mathilde M; Kef, Sabina; Sterkenburg, Paula S; Schuengel, Carlo

2017-01-01

Secure parent-child attachment may help children to overcome the challenges of growing up with a visual or visual-and-intellectual impairment. A large literature exists that provides a blueprint for interventions that promote parental sensitivity and secure attachment. The Video-feedback Intervention to promote Positive Parenting (VIPP) is based on that blueprint. While it has been adapted to several specific at risk populations, children with visual impairment may require additional adjustments. This study aimed to identify the themes that should be addressed in adapting VIPP and similar interventions. A Delphi-consultation was conducted with 13 professionals in the field of visual impairment to select the themes for relationship-focused intervention. These themes informed a systematic literature search. Interaction, intersubjectivity, joint attention, exploration, play and specific behavior were the themes mentioned in the Delphi-group. Paired with visual impairment or vision disorders, infants or young children (and their parents) the search yielded 74 articles, making the six themes for intervention adaptation more specific and concrete. The rich literature on six visual impairment specific themes was dominated by the themes interaction, intersubjectivity, and joint attention. These themes need to be addressed in adapting intervention programs developed for other populations, such as VIPP which currently focuses on higher order constructs of sensitivity and attachment.

Blindness and Visual Impairment in an Urban West African Population: The Tema Eye Survey

PubMed Central

Budenz, Donald L.; Bandi, Jagadeesh R.; Barton, Keith; Nolan, Winifred; Herndon, Leon; Whiteside-de Vos, Julia; Hay-Smith, Graham; Kim, Hanna; Tielsch, James

2012-01-01

Objective To determine the prevalence, etiologies, and risk factors of blindness and visual impairment among persons age 40 years and older residing in an urban West African location. Design Population-based cross-sectional study. Participants Five thousand six hundred and three participants residing in Tema, Ghana. Methods Proportionate random cluster sampling was used to select participants age 40 and over living in the city of Tema. Presenting distance visual acuity was measured at 4 and 1 meters using a reduced Logarithm of the Minimum Angle of Resolution (logMAR) tumbling E chart and then with trial frame based on autorefraction. A screening examination was performed in the field on all participants. Complete clinical examination by an ophthalmologist was performed on participants with best corrected visual acuity < 20/40 or failure of any screening test. Main Outcome Measures Age- and gender-specific prevalence, causes, and risk factors for blindness (visual acuity in the better eye of < 20/400, World Health Organization definition) and visual impairment (visual acuity in the better eye of < 20/40). Results Six thousand eight hundred and six eligible participants were identified of which 5603 (82.3%) participated in the study. The mean age (±standard deviation) of participants was 52.7±10.9. The prevalence of visual impairment was 17.1% and blindness was 1.2%. After refraction and spectacle correction, the prevalence of visual impairment and blindness decreased to 6.7% and 0.75% respectively, suggesting that refractive error is the major correctable etiology of visual impairment and blindness in this population. Of 65 subjects having visual acuity < 20/400, 22 (34%) were correctable with refraction, 21 to the level of visual impairment, and one to normal. The remaining 43 (66%) had underlying pathology (19 cataract, 9 glaucoma, 3 non-glaucomatous optic neuropathy, 3 corneal opacities, 3 retinal disease, 5 undetermined) that prevented refractive correction. Increased age was a significant risk factor for blindness and visual impairment. Conclusions There is a high prevalence of blindness and visual impairment among those aged ≥40 years in Tema, Ghana, West Africa. Refractive error is a major cause of blindness and visual impairment in this population, followed by cataract, glaucoma, and corneal disease. PMID:22677425

[Prevalence of blindness and moderate and severe visual impairment among adults aged 50 years or above in Yangxi County of Guangdong Province: the China Nine-Province Survey].

PubMed

Ge, Jian; He, Mingguang; Zhao, Jialiang; Fang, Min; Ellwein, Leon B; He, Ning; Yang, Mei; Wang, Yu; Gao, Xuecheng

2014-03-01

To investigate the prevalence of blindness and moderate and severe visual impairment among adults aged 50 years or above in Yangxi County of Guangdong Province, China. It was a population-based cross-section study.Geographically defined cluster sampling was used in randomly selecting 5 531 individuals aged 50 years or above in Yangxi County from September 2006 to January 2007. The survey was preceded by a pilot study where operational methods were refined and quality assurance evaluation was carried out. All participants were enumerated using village registers followed by door-to-door visits.Eligible individuals were invited to receive visual acuity measurement and eye examination.Statistical analyses were performed using Stata/SE Statistical Software, release 9.0. Chi-square test was used to investigate the association of age, gender and education with presenting and best corrected visual acuity. Five thousands five hundreds and thirty-one individuals were enumerated and 4 589 persons were examined, the response rate was 82.97%. Based on the criteria of World Health Organization visual impairment classification in 1973, the prevalence of blindness and moderate and severe visual impairment defined as best corrected visual acuity was 2.38% (109/4 589) and 9.44% (433/4 589) respectively. The prevalence of blindness and moderate and severe visual impairment defined as presenting visual acuity was 2.68% (123/4 589) and 18.15% (833/4 589) respectively. The prevalence of blindness and moderate and severe visual impairment was higher in aged (trend χ(2) = 1 239.34, P < 0.01) , female (χ(2) = 37.88, P < 0.01) and illiterate (trend χ(2) = 235.11, P < 0.01) persons. Cataract was the first leading cause of blindness and visual impairment. The prevalence of blindness and moderate and severe visual impairment is higher among older adults aged 50 years or above in Yangxi County. Cataract remains as the first leading cause of blindness and visual impairment.

Screening methods for post-stroke visual impairment: a systematic review.

PubMed

Hanna, Kerry Louise; Hepworth, Lauren Rachel; Rowe, Fiona

2017-12-01

To provide a systematic overview of the various tools available to screen for post-stroke visual impairment. A review of the literature was conducted including randomised controlled trials, controlled trials, cohort studies, observational studies, systematic reviews and retrospective medical note reviews. All languages were included and translation was obtained. Participants included adults ≥18 years old diagnosed with a visual impairment as a direct cause of a stroke. We searched a broad range of scholarly online resources and hand-searched articles registers of published, unpublished and on-going trials. Search terms included a variety of MESH terms and alternatives in relation to stroke and visual conditions. Study selection was performed by two authors independently. The quality of the evidence and risk of bias were assessed using the STROBE, GRACE and PRISMA statements. A total of 25 articles (n = 2924) were included in this review. Articles appraised reported on tools screening solely for visual impairments or for general post-stroke disabilities inclusive of vision. The majority of identified tools screen for visual perception including visual neglect (VN), with few screening for visual acuity (VA), visual field (VF) loss or ocular motility (OM) defects. Six articles reported on nine screening tools which combined visual screening assessment alongside screening for general stroke disabilities. Of these, three included screening for VA; three screened for VF loss; three screened for OM defects and all screened for VN. Two tools screened for all visual impairments. A further 19 articles were found which reported on individual vision screening tests in stroke populations; two for VF loss; 11 for VN and six for other visual perceptual defects. Most tools cannot accurately account for those with aphasia or communicative deficits, which are common problems following a stroke. There is currently no standardised visual screening tool which can accurately assess all potential post-stroke visual impairments. The current tools screen for only a number of potential stroke-related impairments, which means many visual defects may be missed. The sensitivity of those which screen for all impairments is significantly lowered when patients are unable to report their visual symptoms. Future research is required to develop a tool capable of assessing stroke patients which encompasses all potential visual deficits and can also be easily performed by both the patients and administered by health care professionals in order to ensure all stroke survivors with visual impairment are accurately identified and managed. Implications for Rehabilitation Over 65% of stroke survivors will suffer from a visual impairment, whereas 45% of stroke units do not assess vision. Visual impairment significantly reduces the quality of life, such as being unable to return to work, driving and depression. This review outlines the available screening methods to accurately identify stroke survivors with visual impairments. Identifying visual impairment after stroke can aid general rehabilitation and thus, improve the quality of life for these patients.

Is selective mutism associated with deficits in memory span and visual memory?: An exploratory case-control study.

PubMed

Kristensen, Hanne; Oerbeck, Beate

2006-01-01

Our main aim in this study was to explore the association between selective mutism (SM) and aspects of nonverbal cognition such as visual memory span and visual memory. Auditory-verbal memory span was also examined. The etiology of SM is unclear, and it probably represents a heterogeneous condition. SM is associated with language impairment, but nonspecific neurodevelopmental factors, including motor problems, are also reported in SM without language impairment. Furthermore, SM is described in Asperger's syndrome. Studies on nonverbal cognition in SM thus merit further investigation. Neuropsychological tests were administered to a clinical sample of 32 children and adolescents with SM (ages 6-17 years, 14 boys and 18 girls) and 62 nonreferred controls matched for age, gender, and socioeconomic status. We used independent t-tests to compare groups with regard to auditory-verbal memory span, visual memory span, and visual memory (Benton Visual Retention Test), and employed linear regression analysis to study the impact of SM on visual memory, controlling for IQ and measures of language and motor function. The SM group differed from controls on auditory-verbal memory span but not on visual memory span. Controlled for IQ, language, and motor function, the SM group did not differ from controls on visual memory. Motor function was the strongest predictor of visual memory performance. SM does not appear to be associated with deficits in visual memory span or visual memory. The reduced auditory-verbal memory span supports the association between SM and language impairment. More comprehensive neuropsychological studies are needed.

Impact of oral health education by audio aids, braille and tactile models on the oral health status of visually impaired children of Bhopal City.

PubMed

Gautam, Anjali; Bhambal, Ajay; Moghe, Swapnil

2018-01-01

Children with special needs face unique challenges in day-to-day practice. They are dependent on their close ones for everything. To improve oral hygiene in such visually impaired children, undue training and education are required. Braille is an important language for reading and writing for the visually impaired. It helps them understand and visualize the world via touch. Audio aids are being used to impart health education to the visually impaired. Tactile models help them perceive things which they cannot visualize and hence are an important learning tool. This study aimed to assess the improvement in oral hygiene by audio aids and Braille and tactile models in visually impaired children aged 6-16 years of Bhopal city. This was a prospective study. Sixty visually impaired children aged 6-16 years were selected and randomly divided into three groups (20 children each). Group A: audio aids + Braille, Group B: audio aids + tactile models, and Group C: audio aids + Braille + tactile models. Instructions were given for maintaining good oral hygiene and brushing techniques were explained to all children. After 3 months' time, the oral hygiene status was recorded and compared using plaque and gingival index. ANNOVA test was used. The present study showed a decrease in the mean plaque and gingival scores at all time intervals in individual group as compared to that of the baseline that was statistically significant. The study depicts that the combination of audio aids, Braille and tactile models is an effective way to provide oral health education and improve oral health status of visually impaired children.

Visual impairment and blindness in Hungary.

PubMed

Szabó, Dorottya; Sándor, Gábor László; Tóth, Gábor; Pék, Anita; Lukács, Regina; Szalai, Irén; Tóth, Georgina Zsófia; Papp, András; Nagy, Zoltán Zsolt; Limburg, Hans; Németh, János

2018-03-01

The aim of this study was to estimate the prevalence and causes of blindness, severe visual impairment (SVI), moderate visual impairment (MVI), and early visual impairment (EVI) and its causes in an established market economy of Europe. A cross-sectional population-based survey. A sample size of 3675 was calculated using the standard Rapid Assessment of Avoidable Blindness (RAAB) software in Hungary. A total of 105 clusters of 35 people aged 50 years or older were randomly selected with probability proportionate to size by the Hungarian Central Statistical Office. Households within the clusters were selected using compact segment sampling. Visual acuity (VA) was assessed with a Snellen tumbling E-chart with or without a pinhole in the households. The adjusted prevalences of bilateral blindness, SVI, MVI and EVI were 0.9% (95% CI: 0.6-1.2), 0.5% (95% CI: 0.2-0.7), 5.1% (95% CI: 4.3-5.9) and 6.9% (95% CI: 5.9-7.9), respectively. The major causes of blindness in Hungary were age-related macular degeneration (AMD; 27.3%) and other posterior segment diseases (27.3%), cataract (21.2%) and glaucoma (12.1%). Cataract was the main cause of SVI, MVI and EVI. Cataract surgical coverage (CSC) was 90.7%. Of all bilateral blindness in Hungary, 45.5% was considered avoidable. This study proved that RAAB methodology can be successfully conducted in industrialized countries, which often lack reliable epidemiologic data. The prevalence of blindness was relatively low, with AMD and other posterior segment diseases being the leading causes, and cataract is still a significant cause of visual impairment. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Inappropriate enrollment of children in schools for the visually impaired in east Africa.

PubMed

Tumwesigye, C; Msukwa, G; Njuguna, M; Shilio, B; Courtright, P; Lewallen, S

2009-06-01

Many visually impaired children can learn to read print with appropriate training and simple visual aids. This may allow them to attend normal schools and to be integrated into society, which has lifelong benefits. Yet, in Africa, many visually impaired children are enrolled in special schools and taught only Braille. The purpose of this analysis was to document the extent of inappropriate enrollment of visually impaired children in special schools and annexes for the blind in four African countries. Schools were selected through a population-proportional-to-size method so that they would represent all children attending special schools in Kenya, Malawi, Tanzania and Uganda. Children were examined by ophthalmologists trained in standardised methods to determine visual acuity and the cause of decreased acuity. Of 1062 children examined in special schools and annexes for the blind, 361 (34%, 95% CI 31.2, 36.8) had visual acuity >or=6/60; the most common cause of visual impairment was retinal disease. Of the 120 children with normal vision (>or=6/18), 69 (57.5%) had two normal eyes, 21 (17.5%) had an obvious ocular disfigurement in the fellow eye and 10 (8.4%) had had successful cataract surgery. In these countries, many children are placed inappropriately in special schools and annexes for the blind. The reasons are multiple and to rectify the situation will require advocacy and cooperation between ministries of health and education.

[Survey on avoidable blindness and visual impairment in Panama].

PubMed

López, Maritza; Brea, Ileana; Yee, Rita; Yi, Rodolfo; Carles, Víctor; Broce, Alberto; Limburg, Hans; Silva, Juan Carlos

2014-12-01

Determine prevalence of blindness and visual impairment in adults aged ≥ 50 years in Panama, identify their main causes, and characterize eye health services. Cross-sectional population study using standard Rapid Assessment of Avoidable Blindness methodology. Fifty people aged ≥ 50 years were selected from each of 84 clusters chosen through representative random sampling of the entire country. Visual acuity was assessed using a Snellen chart; lens and posterior pole status were assessed by direct ophthalmoscopy. Cataract surgery coverage was calculated and its quality assessed, along with causes of visual acuity < 20/60 and barriers to access to surgical treatment. A total of 4 125 people were examined (98.2% of the calculated sample). Age- and sex-adjusted prevalence of blindness was 3.0% (95% CI: 2.3-3.6). The main cause of blindness was cataract (66.4%), followed by glaucoma (10.2%). Cataract (69.2%) was the main cause of severe visual impairment and uncorrected refractive errors were the main cause of moderate visual impairment (60.7%). Surgical cataract coverage in individuals was 76.3%. Of all eyes operated for cataract, 58.0% achieved visual acuity ≤ 20/60 with available correction. Prevalence of blindness in Panama is in line with average prevalence found in other countries of the Region. This problem can be reduced, since 76.2% of cases of blindness and 85.0% of cases of severe visual impairment result from avoidable causes.

Barriers to the Use of Computer Assistive Technology among Students with Visual Impairment in Ghana: The Case of Akropong School for the Blind

ERIC Educational Resources Information Center

Ampratwum, Joseph; Offei, Yaw Nyadu; Ntoaduro, Afua

2016-01-01

The study aimed at exploring barriers to the use of computer assistive technology among students with visual impairment at Akropong School for the Blind. A case study design was adopted and the purposive sampling technique used to select 35 participants for the study. The researchers gathered qualitative data using an in-depth interview guide to…

Analysis of user characteristics related to drop-off detection with long cane

PubMed Central

Kim, Dae Shik; Emerson, Robert Wall; Curtis, Amy

2010-01-01

This study examined how user characteristics affect drop-off detection with the long cane. A mixed-measures design with block randomization was used for the study, in which 32 visually impaired adults attempted to detect the drop-offs using different cane techniques. Younger cane users detected drop-offs significantly more reliably (mean +/− standard deviation = 74.2% +/− 11.2% of the time) than older cane users (60.9% +/− 10.8%), p = 0.009. The drop-off detection threshold of the younger participants (5.2 +/− 2.1 cm) was also statistically significantly smaller than that of the older participants (7.9 +/− 2.2 cm), p = 0.007. Those with early-onset visual impairment (78.0% +/− 9.0%) also detected drop-offs significantly more reliably than those with later-onset visual impairment (67.3% +/− 12.4%), p = 0.01. No interaction occurred between examined user characteristics (age and age at onset of visual impairment) and the type of cane technique used in drop-off detection. The findings of the study may help orientation and mobility specialists select appropriate cane techniques in accordance with the cane user’s age and onset of visual impairment. PMID:20665349

Social exclusion impairs distractor suppression but not target enhancement in selective attention.

PubMed

Xu, Mengsi; Li, Zhiai; Diao, Liuting; Fan, Lingxia; Zhang, Lijie; Yuan, Shuge; Yang, Dong

2017-11-01

Social exclusion has been thought to weaken one's ability to exert inhibitory control. Existing studies have primarily focused on the relationship between exclusion and behavioral inhibition, and have reported that exclusion impairs behavioral inhibition. However, whether exclusion also affects selective attention, another important aspect of inhibitory control, remains unknown. Therefore, the current study aimed to explore whether social exclusion impairs selective attention, and to specifically examine its effect on two hypothesized mechanisms of selective attention: target enhancement and distractor suppression. The Cyberball game was used to manipulate social exclusion. Participants then performed a visual search task while event-related potentials were recorded. In the visual search task, target and salient distractor were either both presented laterally or one was presented on the vertical midline and the other laterally. Results showed that social exclusion differentially affected target and distractor processing. While exclusion impaired distractor suppression, reflected as smaller distractor-positivity (Pd) amplitudes for the exclusion group compared to the inclusion group, it did not affect target enhancement, reflected as similar target-negativity (Nt) amplitudes for both the exclusion and inclusion groups. Together, these results extend our understanding of the relationship between exclusion and inhibitory control, and suggest that social exclusion affects selective attention in a more complex manner than previously thought. Copyright © 2017. Published by Elsevier B.V.

Rapid Assessment of Visual Impairment in Urban Population of Delhi, India

PubMed Central

Gupta, Noopur; Vashist, Praveen; Malhotra, Sumit; Senjam, Suraj Singh; Misra, Vasundhara; Bhardwaj, Amit

2015-01-01

Purpose To determine the prevalence, causes and associated demographic factors related to visual impairment amongst the urban population of New Delhi, India. Methods A population-based, cross-sectional study was conducted in East Delhi district using cluster random sampling methodology. This Rapid Assessment of Visual Impairment (RAVI) survey involved examination of all individuals aged 40 years and above in 24 randomly selected clusters of the district. Visual acuity (VA) assessment and comprehensive ocular examination were done during the door-to-door survey. A questionnaire was used to collect personal and demographic information of the study population. Blindness and Visual Impairment was defined as presenting VA <3/60and <6/18 in the better eye, respectively. Descriptive statistics were computed along with multivariable logistic regression analysis to determine associated factors for visual impairment. Results Of 2421 subjects enumerated, 2331 (96.3%) were available for ophthalmic examination. Among those examined, 49.3% were males. The prevalence of visual impairment (VI) in the study population, was 11.4% (95% C.I. 10.1, 12.7) and that of blindness was 1.2% (95% C.I. 0.8, 1.6). Uncorrected refractive error was the leading cause of VI accounting for 53.4% of all VI followed by cataract (33.8%). With multivariable logistic regression, the odds of having VI increased with age (OR= 24.6[95% C.I.: 14.9, 40.7]; p<0.001). Illiterate participants were more likely to have VI [OR= 1.5 (95% C.I.: 1.1,2.1)] when compared to educated participants. Conclusions The first implementation of the RAVI methodology in a North Indian population revealed that the burden of visual impairment is considerable in this region despite availability of adequate eye care facilities. Awareness generation and simple interventions like cataract surgery and provision of spectacles will help to eliminate the major causes of blindness and visual impairment in this region. PMID:25915659

Rapid assessment of visual impairment in urban population of Delhi, India.

PubMed

Gupta, Noopur; Vashist, Praveen; Malhotra, Sumit; Senjam, Suraj Singh; Misra, Vasundhara; Bhardwaj, Amit

2015-01-01

To determine the prevalence, causes and associated demographic factors related to visual impairment amongst the urban population of New Delhi, India. A population-based, cross-sectional study was conducted in East Delhi district using cluster random sampling methodology. This Rapid Assessment of Visual Impairment (RAVI) survey involved examination of all individuals aged 40 years and above in 24 randomly selected clusters of the district. Visual acuity (VA) assessment and comprehensive ocular examination were done during the door-to-door survey. A questionnaire was used to collect personal and demographic information of the study population. Blindness and Visual Impairment was defined as presenting VA < 3/60 and < 6/18 in the better eye, respectively. Descriptive statistics were computed along with multivariable logistic regression analysis to determine associated factors for visual impairment. Of 2421 subjects enumerated, 2331 (96.3%) were available for ophthalmic examination. Among those examined, 49.3% were males. The prevalence of visual impairment (VI) in the study population, was 11.4% (95% C.I. 10.1, 12.7) and that of blindness was 1.2% (95% C.I. 0.8, 1.6). Uncorrected refractive error was the leading cause of VI accounting for 53.4% of all VI followed by cataract (33.8%). With multivariable logistic regression, the odds of having VI increased with age (OR = 24.6[95% C.I.: 14.9, 40.7]; p < 0.001). Illiterate participants were more likely to have VI [OR = 1.5 (95% C.I.: 1.1,2.1)] when compared to educated participants. The first implementation of the RAVI methodology in a North Indian population revealed that the burden of visual impairment is considerable in this region despite availability of adequate eye care facilities. Awareness generation and simple interventions like cataract surgery and provision of spectacles will help to eliminate the major causes of blindness and visual impairment in this region.

Prevalence of visual impairment and blindness in Upper Egypt: a gender-based perspective.

PubMed

Mousa, Ahmed; Courtright, Paul; Kazanjian, Arminee; Bassett, Ken

2014-06-01

To estimate the prevalence, causes of and risk factors for vision loss in Upper Egypt. In this cross-sectional study, four villages in Upper Egypt were randomly selected; within these four villages, households were randomly selected and within the selected households all residents aged ≥ 40 years were enumerated and enrolled. Door-to-door eye examinations of household members were conducted. Data on relevant demographic and socioeconomic characteristics were collected. The prevalence and causes of vision loss and associated risk factors were assessed. Sex differences in prevalence and determinants were also evaluated. The prevalence of best eye presenting visual impairment, severe visual impairment, and blindness were 23.9%, 6.4%, and 9.3% respectively. The prevalence of blindness among women significantly exceeded that among men (11.8% vs. 5.4%, respectively, p = 0.021). The prevalence of cataract was 22.9% (higher in women, 26.5% than men 17.2%, p = 0.018). The prevalence of trachomatous trichiasis was 9.7% (higher among women, 12.5%, than men, 5.4%, p = 0.012). The principal causes of blindness were cataract (60%), uncorrected refractive errors (16%) and corneal opacities (12%). Age, sex, family size, illiteracy, unemployment, water source and sanitation methods and living conditions were the major risk factors for vision loss. The prevalence of visual impairment remains high in Egypt, particularly among women. Risk factors for blindness may differ between men and women. There is a need for qualitative investigations to better understand the causes behind the excess in prevalence of blindness among women.

Causes of blindness and visual impairment in Pakistan. The Pakistan national blindness and visual impairment survey

PubMed Central

Dineen, B; Bourne, R R A; Jadoon, Z; Shah, S P; Khan, M A; Foster, A; Gilbert, C E; Khan, M D

2007-01-01

Objective To determine the causes of blindness and visual impairment in adults (⩾30 years old) in Pakistan, and to explore socio‐demographic variations in cause. Methods A multi‐stage, stratified, cluster random sampling survey was used to select a nationally representative sample of adults. Each subject was interviewed, had their visual acuity measured and underwent autorefraction and fundus/optic disc examination. Those with a visual acuity of <6/12 in either eye underwent a more detailed ophthalmic examination. Causes of visual impairment were classified according to the accepted World Health Organization (WHO) methodology. An exploration of demographic variables was conducted using regression modeling. Results A sample of 16 507 adults (95.5% of those enumerated) was examined. Cataract was the most common cause of blindness (51.5%; defined as <3/60 in the better eye on presentation) followed by corneal opacity (11.8%), uncorrected aphakia (8.6%) and glaucoma (7.1%). Posterior capsular opacification accounted for 3.6% of blindness. Among the moderately visually impaired (<6/18 to ⩾6/60), refractive error was the most common cause (43%), followed by cataract (42%). Refractive error as a cause of severe visual impairment/blindness was significantly higher in rural dwellers than in urban dwellers (odds ratio (OR) 3.5, 95% CI 1.1 to 11.7). Significant provincial differences were also identified. Overall we estimate that 85.5% of causes were avoidable and that 904 000 adults in Pakistan have cataract (<6/60) requiring surgical intervention. Conclusions This comprehensive survey provides reliable estimates of the causes of blindness and visual impairment in Pakistan. Despite expanded surgical services, cataract still accounts for over half of the cases of blindness in Pakistan. One in eight blind adults has visual loss from sequelae of cataract surgery. Services for refractive errors need to be further expanded and integrated into eye care services, particularly those serving rural populations. PMID:17229806

Differential effects of m1 and m2 receptor antagonists in perirhinal cortex on visual recognition memory in monkeys

PubMed Central

Wu, Wei; Saunders, Richard C.; Mishkin, Mortimer; Turchi, Janita

2012-01-01

Microinfusions of the nonselective muscarinic antagonist scopolamine into perirhinal cortex impairs performance on visual recognition tasks, indicating that muscarinic receptors in this region play a pivotal role in recognition memory. To assess the mnemonic effects of selective blockade in perirhinal cortex of muscarinic receptor subtypes, we locally infused either the m1-selective antagonist pirenzepine or the m2-selective antagonist methoctramine in animals performing one-trial visual recognition, and compared these scores with those following infusions of equivalent volumes of saline. Compared to these control infusions, injections of pirenzepine, but not of methoctramine, significantly impaired recognition accuracy. Further, similar doses of scopolamine and pirenzepine yielded similar deficits, suggesting that the deficits obtained earlier with scopolamine were due mainly, if not exclusively, to blockade of m1 receptors. The present findings indicate that m1 and m2 receptors have functionally dissociable roles, and that the formation of new visual memories is critically dependent on the cholinergic activation of m1 receptors located on perirhinal cells. PMID:22561485

Differential effects of m1 and m2 receptor antagonists in perirhinal cortex on visual recognition memory in monkeys.

PubMed

Wu, Wei; Saunders, Richard C; Mishkin, Mortimer; Turchi, Janita

2012-07-01

Microinfusions of the nonselective muscarinic antagonist scopolamine into perirhinal cortex impairs performance on visual recognition tasks, indicating that muscarinic receptors in this region play a pivotal role in recognition memory. To assess the mnemonic effects of selective blockade in perirhinal cortex of muscarinic receptor subtypes, we locally infused either the m1-selective antagonist pirenzepine or the m2-selective antagonist methoctramine in animals performing one-trial visual recognition, and compared these scores with those following infusions of equivalent volumes of saline. Compared to these control infusions, injections of pirenzepine, but not of methoctramine, significantly impaired recognition accuracy. Further, similar doses of scopolamine and pirenzepine yielded similar deficits, suggesting that the deficits obtained earlier with scopolamine were due mainly, if not exclusively, to blockade of m1 receptors. The present findings indicate that m1 and m2 receptors have functionally dissociable roles, and that the formation of new visual memories is critically dependent on the cholinergic activation of m1 receptors located on perirhinal cells. Published by Elsevier Inc.

The effect of perceptual load on attention-induced motion blindness: the efficiency of selective inhibition.

PubMed

Hay, Julia L; Milders, Maarten M; Sahraie, Arash; Niedeggen, Michael

2006-08-01

Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. ((c) 2006 APA, all rights reserved).

Mental workload while driving: effects on visual search, discrimination, and decision making.

PubMed

Recarte, Miguel A; Nunes, Luis M

2003-06-01

The effects of mental workload on visual search and decision making were studied in real traffic conditions with 12 participants who drove an instrumented car. Mental workload was manipulated by having participants perform several mental tasks while driving. A simultaneous visual-detection and discrimination test was used as performance criteria. Mental tasks produced spatial gaze concentration and visual-detection impairment, although no tunnel vision occurred. According to ocular behavior analysis, this impairment was due to late detection and poor identification more than to response selection. Verbal acquisition tasks were innocuous compared with production tasks, and complex conversations, whether by phone or with a passenger, are dangerous for road safety.

Too little, too late: reduced visual span and speed characterize pure alexia.

PubMed

Starrfelt, Randi; Habekost, Thomas; Leff, Alexander P

2009-12-01

Whether normal word reading includes a stage of visual processing selectively dedicated to word or letter recognition is highly debated. Characterizing pure alexia, a seemingly selective disorder of reading, has been central to this debate. Two main theories claim either that 1) Pure alexia is caused by damage to a reading specific brain region in the left fusiform gyrus or 2) Pure alexia results from a general visual impairment that may particularly affect simultaneous processing of multiple items. We tested these competing theories in 4 patients with pure alexia using sensitive psychophysical measures and mathematical modeling. Recognition of single letters and digits in the central visual field was impaired in all patients. Visual apprehension span was also reduced for both letters and digits in all patients. The only cortical region lesioned across all 4 patients was the left fusiform gyrus, indicating that this region subserves a function broader than letter or word identification. We suggest that a seemingly pure disorder of reading can arise due to a general reduction of visual speed and span, and explain why this has a disproportionate impact on word reading while recognition of other visual stimuli are less obviously affected.

Too Little, Too Late: Reduced Visual Span and Speed Characterize Pure Alexia

PubMed Central

Habekost, Thomas; Leff, Alexander P.

2009-01-01

Whether normal word reading includes a stage of visual processing selectively dedicated to word or letter recognition is highly debated. Characterizing pure alexia, a seemingly selective disorder of reading, has been central to this debate. Two main theories claim either that 1) Pure alexia is caused by damage to a reading specific brain region in the left fusiform gyrus or 2) Pure alexia results from a general visual impairment that may particularly affect simultaneous processing of multiple items. We tested these competing theories in 4 patients with pure alexia using sensitive psychophysical measures and mathematical modeling. Recognition of single letters and digits in the central visual field was impaired in all patients. Visual apprehension span was also reduced for both letters and digits in all patients. The only cortical region lesioned across all 4 patients was the left fusiform gyrus, indicating that this region subserves a function broader than letter or word identification. We suggest that a seemingly pure disorder of reading can arise due to a general reduction of visual speed and span, and explain why this has a disproportionate impact on word reading while recognition of other visual stimuli are less obviously affected. PMID:19366870

Prevalence of Dental Caries, Oral Hygiene Knowledge, Status, and Practices among Visually Impaired Individuals in Chennai, Tamil Nadu.

PubMed

John, James Rufus; Daniel, Breena; Paneerselvam, Dakshaini; Rajendran, Ganesh

2017-01-01

Aim . To assess the prevalence of dental caries, oral hygiene knowledge, status, and practices among visually impaired individuals in Chennai, Tamil Nadu. Materials and Methods . A cross-sectional study was conducted among 404 visually impaired individuals in Chennai city, Tamil Nadu. Four schools were randomly selected for conducting the study. The oral hygiene status, prevalence of caries, and knowledge and attitude towards oral care among visually impaired individuals were collected and analysed. Results . In the present study, whilst 42% of individuals had fair oral hygiene status, 33% had good hygiene followed by 25% having poor oral hygiene. The overall mean number of DMFT was estimated to be 4.5 ± 2.7. The mean number of decayed teeth was 3.1 ± 2.2, mean number of missing teeth was 0.8 ± 1.4, and mean number of filled teeth was 0.5 ± 1.3. Conclusion . Whilst oral hygiene status was found to be relatively fair, there was a high rate of dental caries among the sample population. This shows that there is lack of knowledge regarding oral health maintenance. Therefore, early identification of caries coupled with effective oral health promotion programs providing practical knowledge to visually impaired students would prove beneficial.

Prevalence of Dental Caries, Oral Hygiene Knowledge, Status, and Practices among Visually Impaired Individuals in Chennai, Tamil Nadu

PubMed Central

Daniel, Breena; Paneerselvam, Dakshaini; Rajendran, Ganesh

2017-01-01

Aim. To assess the prevalence of dental caries, oral hygiene knowledge, status, and practices among visually impaired individuals in Chennai, Tamil Nadu. Materials and Methods. A cross-sectional study was conducted among 404 visually impaired individuals in Chennai city, Tamil Nadu. Four schools were randomly selected for conducting the study. The oral hygiene status, prevalence of caries, and knowledge and attitude towards oral care among visually impaired individuals were collected and analysed. Results. In the present study, whilst 42% of individuals had fair oral hygiene status, 33% had good hygiene followed by 25% having poor oral hygiene. The overall mean number of DMFT was estimated to be 4.5 ± 2.7. The mean number of decayed teeth was 3.1 ± 2.2, mean number of missing teeth was 0.8 ± 1.4, and mean number of filled teeth was 0.5 ± 1.3. Conclusion. Whilst oral hygiene status was found to be relatively fair, there was a high rate of dental caries among the sample population. This shows that there is lack of knowledge regarding oral health maintenance. Therefore, early identification of caries coupled with effective oral health promotion programs providing practical knowledge to visually impaired students would prove beneficial. PMID:28458691

Information processing of visually presented picture and word stimuli by young hearing-impaired and normal-hearing children.

PubMed

Kelly, R R; Tomlison-Keasey, C

1976-12-01

Eleven hearing-impaired children and 11 normal-hearing children (mean = four years 11 months) were visually presented familiar items in either picture or word form. Subjects were asked to recognize the stimuli they had seen from cue cards consisting of pictures or words. They were then asked to recall the sequence of stimuli by arranging the cue cards selected. The hearing-impaired group and normal-hearing subjects performed differently with the picture/picture (P/P) and word/word (W/W) modes in the recognition phase. The hearing impaired performed equally well with both modes (P/P and W/W), while the normal hearing did significantly better on the P/P mode. Furthermore, the normal-hearing group showed no difference in processing like modes (P/P and W/W) when compared to unlike modes (W/P and P/W). In contrast, the hearing-impaired subjects did better on like modes. The results were interpreted, in part, as supporting the position that young normal-hearing children dual code their visual information better than hearing-impaired children.

The role of visual attention in predicting driving impairment in older adults.

PubMed

Hoffman, Lesa; McDowd, Joan M; Atchley, Paul; Dubinsky, Richard

2005-12-01

This study evaluated the role of visual attention (as measured by the DriverScan change detection task and the Useful Field of View Test [UFOV]) in the prediction of driving impairment in 155 adults between the ages of 63 and 87. In contrast to previous research, participants were not oversampled for visual impairment or history of automobile accidents. Although a history of automobile accidents within the past 3 years could not be predicted using any variable, driving performance in a low-fidelity simulator could be significantly predicted by performance in the change detection task and by the divided and selection attention subtests of the UFOV in structural equation models. The sensitivity and specificity of each measure in identifying at-risk drivers were also evaluated with receiver operating characteristic curves.

Visual recognition and visually guided action after early bilateral lesion of occipital cortex: a behavioral study of a 4.6-year-old girl.

PubMed

Amicuzi, Ileana; Stortini, Massimo; Petrarca, Maurizio; Di Giulio, Paola; Di Rosa, Giuseppe; Fariello, Giuseppe; Longo, Daniela; Cannatà, Vittorio; Genovese, Elisabetta; Castelli, Enrico

2006-10-01

We report the case of a 4.6-year-old girl born pre-term with early bilateral occipital damage. It was revealed that the child had non-severely impaired basic visual abilities and ocular motility, a selective perceptual deficit of figure-ground segregation, impaired visual recognition and abnormal navigating through space. Even if the child's visual functioning was not optimal, this was the expression of adaptive anatomic and functional brain modifications that occurred following the early lesion. Anatomic brain structure was studied with anatomic MRI and Diffusor Tensor Imaging (DTI)-MRI. This behavioral study may provide an important contribution to understanding the impact of an early lesion of the visual system on the development of visual functions and on the immature brain's potential for reorganisation related to when the damage occurred.

Examining sensory ability, feature matching and assessment-based adaptation for a brain-computer interface using the steady-state visually evoked potential.

PubMed

Brumberg, Jonathan S; Nguyen, Anh; Pitt, Kevin M; Lorenz, Sean D

2018-01-31

We investigated how overt visual attention and oculomotor control influence successful use of a visual feedback brain-computer interface (BCI) for accessing augmentative and alternative communication (AAC) devices in a heterogeneous population of individuals with profound neuromotor impairments. BCIs are often tested within a single patient population limiting generalization of results. This study focuses on examining individual sensory abilities with an eye toward possible interface adaptations to improve device performance. Five individuals with a range of neuromotor disorders participated in four-choice BCI control task involving the steady state visually evoked potential. The BCI graphical interface was designed to simulate a commercial AAC device to examine whether an integrated device could be used successfully by individuals with neuromotor impairment. All participants were able to interact with the BCI and highest performance was found for participants able to employ an overt visual attention strategy. For participants with visual deficits to due to impaired oculomotor control, effective performance increased after accounting for mismatches between the graphical layout and participant visual capabilities. As BCIs are translated from research environments to clinical applications, the assessment of BCI-related skills will help facilitate proper device selection and provide individuals who use BCI the greatest likelihood of immediate and long term communicative success. Overall, our results indicate that adaptations can be an effective strategy to reduce barriers and increase access to BCI technology. These efforts should be directed by comprehensive assessments for matching individuals to the most appropriate device to support their complex communication needs. Implications for Rehabilitation Brain computer interfaces using the steady state visually evoked potential can be integrated with an augmentative and alternative communication device to provide access to language and literacy for individuals with neuromotor impairment. Comprehensive assessments are needed to fully understand the sensory, motor, and cognitive abilities of individuals who may use brain-computer interfaces for proper feature matching as selection of the most appropriate device including optimization device layouts and control paradigms. Oculomotor impairments negatively impact brain-computer interfaces that use the steady state visually evoked potential, but modifications to place interface stimuli and communication items in the intact visual field can improve successful outcomes.

Age and visual impairment decrease driving performance as measured on a closed-road circuit.

PubMed

Wood, Joanne M

2002-01-01

In this study the effects of visual impairment and age on driving were investigated and related to visual function. Participants were 139 licensed drivers (young, middle-aged, and older participants with normal vision, and older participants with ocular disease). Driving performance was assessed during the daytime on a closed-road driving circuit. Visual performance was assessed using a vision testing battery. Age and visual impairment had a significant detrimental effect on recognition tasks (detection and recognition of signs and hazards), time to complete driving tasks (overall course time, reversing, and maneuvering), maneuvering ability, divided attention, and an overall driving performance index. All vision measures were significantly affected by group membership. A combination of motion sensitivity, useful field of view (UFOV), Pelli-Robson letter contrast sensitivity, and dynamic acuity could predict 50% of the variance in overall driving scores. These results indicate that older drivers with either normal vision or visual impairment had poorer driving performance compared with younger or middle-aged drivers with normal vision. The inclusion of tests such as motion sensitivity and the UFOV significantly improve the predictive power of vision tests for driving performance. Although such measures may not be practical for widespread screening, their application in selected cases should be considered.

Prevalence of blindness and diabetic retinopathy in northern Jordan.

PubMed

Rabiu, Mansur M; Al Bdour, Muawyah D; Abu Ameerh, Mohammed A; Jadoon, Muhammed Z

2015-01-01

To estimate the prevalence of blindness, visual impairment, diabetes, and diabetic retinopathy in north Jordan (Irbid) using the rapid assessment of avoidable blindness and diabetic retinopathy methodology. A multistage cluster random sampling technique was used to select participants for this survey. A total of 108 clusters were selected using probability proportional to size method while subjects within the clusters were selected using compact segment method. Survey teams moved from house to house in selected segments examining residents 50 years and older until 35 participants were recruited. All eligible people underwent a standardized examination protocol, which included ophthalmic examination and random blood sugar test using digital glucometers (Accu-Chek) in their homes. Diabetic retinopathy among diabetic patients was assessed through dilated fundus examination. A total of 3638 out of the 3780 eligible participants were examined. Age- and sex-adjusted prevalence of blindness, severe visual impairment, and visual impairment with available correction were 1.33% (95% confidence interval [CI] 0.87-1.73), 1.82% (95% CI 1.35-2.25), and 9.49% (95% CI 8.26-10.74), respectively, all higher in women. Untreated cataract and diabetic retinopathy were the major causes of blindness, accounting for 46.7% and 33.2% of total blindness cases, respectively. Glaucoma was the third major cause, accounting for 8.9% of cases. The prevalence of diabetes mellitus was 28.6% (95% CI 26.9-30.3) among the study population and higher in women. The prevalence of any retinopathy among diabetic patients was 48.4%. Cataract and diabetic retinopathy are the 2 major causes of blindness and visual impairment in northern Jordan. For both conditions, women are primarily affected, suggesting possible limitations to access to services. A diabetic retinopathy screening program needs to proactively create sex-sensitive awareness and provide easily accessible screening services with prompt treatment.

Frontal and parietal theta burst TMS impairs working memory for visual-spatial conjunctions

PubMed Central

Morgan, Helen M.; Jackson, Margaret C.; van Koningsbruggen, Martijn G.; Shapiro, Kimron L.; Linden, David E.J.

2013-01-01

In tasks that selectively probe visual or spatial working memory (WM) frontal and posterior cortical areas show a segregation, with dorsal areas preferentially involved in spatial (e.g. location) WM and ventral areas in visual (e.g. object identity) WM. In a previous fMRI study [1], we showed that right parietal cortex (PC) was more active during WM for orientation, whereas left inferior frontal gyrus (IFG) was more active during colour WM. During WM for colour-orientation conjunctions, activity in these areas was intermediate to the level of activity for the single task preferred and non-preferred information. To examine whether these specialised areas play a critical role in coordinating visual and spatial WM to perform a conjunction task, we used theta burst transcranial magnetic stimulation (TMS) to induce a functional deficit. Compared to sham stimulation, TMS to right PC or left IFG selectively impaired WM for conjunctions but not single features. This is consistent with findings from visual search paradigms, in which frontal and parietal TMS selectively affects search for conjunctions compared to single features, and with combined TMS and functional imaging work suggesting that parietal and frontal regions are functionally coupled in tasks requiring integration of visual and spatial information. Our results thus elucidate mechanisms by which the brain coordinates spatially segregated processing streams and have implications beyond the field of working memory. PMID:22483548

Frontal and parietal theta burst TMS impairs working memory for visual-spatial conjunctions.

PubMed

Morgan, Helen M; Jackson, Margaret C; van Koningsbruggen, Martijn G; Shapiro, Kimron L; Linden, David E J

2013-03-01

In tasks that selectively probe visual or spatial working memory (WM) frontal and posterior cortical areas show a segregation, with dorsal areas preferentially involved in spatial (e.g. location) WM and ventral areas in visual (e.g. object identity) WM. In a previous fMRI study [1], we showed that right parietal cortex (PC) was more active during WM for orientation, whereas left inferior frontal gyrus (IFG) was more active during colour WM. During WM for colour-orientation conjunctions, activity in these areas was intermediate to the level of activity for the single task preferred and non-preferred information. To examine whether these specialised areas play a critical role in coordinating visual and spatial WM to perform a conjunction task, we used theta burst transcranial magnetic stimulation (TMS) to induce a functional deficit. Compared to sham stimulation, TMS to right PC or left IFG selectively impaired WM for conjunctions but not single features. This is consistent with findings from visual search paradigms, in which frontal and parietal TMS selectively affects search for conjunctions compared to single features, and with combined TMS and functional imaging work suggesting that parietal and frontal regions are functionally coupled in tasks requiring integration of visual and spatial information. Our results thus elucidate mechanisms by which the brain coordinates spatially segregated processing streams and have implications beyond the field of working memory. Copyright © 2013 Elsevier Inc. All rights reserved.

Mental rotation impairs attention shifting and short-term memory encoding: neurophysiological evidence against the response-selection bottleneck model of dual-task performance.

PubMed

Pannebakker, Merel M; Jolicœur, Pierre; van Dam, Wessel O; Band, Guido P H; Ridderinkhof, K Richard; Hommel, Bernhard

2011-09-01

Dual tasks and their associated delays have often been used to examine the boundaries of processing in the brain. We used the dual-task procedure and recorded event-related potentials (ERPs) to investigate how mental rotation of a first stimulus (S1) influences the shifting of visual-spatial attention to a second stimulus (S2). Visual-spatial attention was monitored by using the N2pc component of the ERP. In addition, we examined the sustained posterior contralateral negativity (SPCN) believed to index the retention of information in visual short-term memory. We found modulations of both the N2pc and the SPCN, suggesting that engaging mechanisms of mental rotation impairs the deployment of visual-spatial attention and delays the passage of a representation of S2 into visual short-term memory. Both results suggest interactions between mental rotation and visual-spatial attention in capacity-limited processing mechanisms indicating that response selection is not pivotal in dual-task delays and all three processes are likely to share a common resource like executive control. Copyright © 2011 Elsevier Ltd. All rights reserved.

The contribution of LM to the neuroscience of movement vision

PubMed Central

Zihl, Josef; Heywood, Charles A.

2015-01-01

The significance of early and sporadic reports in the 19th century of impairments of motion vision following brain damage was largely unrecognized. In the absence of satisfactory post-mortem evidence, impairments were interpreted as the consequence of a more general disturbance resulting from brain damage, the location and extent of which was unknown. Moreover, evidence that movement constituted a special visual perception and may be selectively spared was similarly dismissed. Such skepticism derived from a reluctance to acknowledge that the neural substrates of visual perception may not be confined to primary visual cortex. This view did not persist. First, it was realized that visual movement perception does not depend simply on the analysis of spatial displacements and temporal intervals, but represents a specific visual movement sensation. Second persuasive evidence for functional specialization in extrastriate cortex, and notably the discovery of cortical area V5/MT, suggested a separate region specialized for motion processing. Shortly thereafter the remarkable case of patient LM was published, providing compelling evidence for a selective and specific loss of movement vision. The case is reviewed here, along with an assessment of its contribution to visual neuroscience. PMID:25741251

Selective impairment of auditory selective attention under concurrent cognitive load.

PubMed

Dittrich, Kerstin; Stahl, Christoph

2012-06-01

Load theory predicts that concurrent cognitive load impairs selective attention. For visual stimuli, it has been shown that this impairment can be selective: Distraction was specifically increased when the stimulus material used in the cognitive load task matches that of the selective attention task. Here, we report four experiments that demonstrate such selective load effects for auditory selective attention. The effect of two different cognitive load tasks on two different auditory Stroop tasks was examined, and selective load effects were observed: Interference in a nonverbal-auditory Stroop task was increased under concurrent nonverbal-auditory cognitive load (compared with a no-load condition), but not under concurrent verbal-auditory cognitive load. By contrast, interference in a verbal-auditory Stroop task was increased under concurrent verbal-auditory cognitive load but not under nonverbal-auditory cognitive load. This double-dissociation pattern suggests the existence of different and separable verbal and nonverbal processing resources in the auditory domain.

A cognitive model for multidigit number reading: Inferences from individuals with selective impairments.

PubMed

Dotan, Dror; Friedmann, Naama

2018-04-01

We propose a detailed cognitive model of multi-digit number reading. The model postulates separate processes for visual analysis of the digit string and for oral production of the verbal number. Within visual analysis, separate sub-processes encode the digit identities and the digit order, and additional sub-processes encode the number's decimal structure: its length, the positions of 0, and the way it is parsed into triplets (e.g., 314987 → 314,987). Verbal production consists of a process that generates the verbal structure of the number, and another process that retrieves the phonological forms of each number word. The verbal number structure is first encoded in a tree-like structure, similarly to syntactic trees of sentences, and then linearized to a sequence of number-word specifiers. This model is based on an investigation of the number processing abilities of seven individuals with different selective deficits in number reading. We report participants with impairment in specific sub-processes of the visual analysis of digit strings - in encoding the digit order, in encoding the number length, or in parsing the digit string to triplets. Other participants were impaired in verbal production, making errors in the number structure (shifts of digits to another decimal position, e.g., 3,040 → 30,004). Their selective deficits yielded several dissociations: first, we found a double dissociation between visual analysis deficits and verbal production deficits. Second, several dissociations were found within visual analysis: a double dissociation between errors in digit order and errors in the number length; a dissociation between order/length errors and errors in parsing the digit string into triplets; and a dissociation between the processing of different digits - impaired order encoding of the digits 2-9, without errors in the 0 position. Third, within verbal production, a dissociation was found between digit shifts and substitutions of number words. A selective deficit in any of the processes described by the model would cause difficulties in number reading, which we propose to term "dysnumeria". Copyright © 2017 Elsevier Ltd. All rights reserved.

Selection and Inhibition in Infancy: Evidence from the Spatial Negative Priming Paradigm

ERIC Educational Resources Information Center

Amso, D.; Johnson, S.P.

2005-01-01

We used a spatial negative priming (SNP) paradigm to examine visual selective attention in infants and adults using eye movements as the motor selection measure. In SNP, when a previously ignored location becomes the target to be selected, responses to it are impaired, providing a measure of inhibitory selection. Each trial consisted of a prime…

Face identity matching is selectively impaired in developmental prosopagnosia.

PubMed

Fisher, Katie; Towler, John; Eimer, Martin

2017-04-01

Individuals with developmental prosopagnosia (DP) have severe face recognition deficits, but the mechanisms that are responsible for these deficits have not yet been fully identified. We assessed whether the activation of visual working memory for individual faces is selectively impaired in DP. Twelve DPs and twelve age-matched control participants were tested in a task where they reported whether successively presented faces showed the same or two different individuals, and another task where they judged whether the faces showed the same or different facial expressions. Repetitions versus changes of the other currently irrelevant attribute were varied independently. DPs showed impaired performance in the identity task, but performed at the same level as controls in the expression task. An electrophysiological marker for the activation of visual face memory by identity matches (N250r component) was strongly attenuated in the DP group, and the size of this attenuation was correlated with poor performance in a standardized face recognition test. Results demonstrate an identity-specific deficit of visual face memory in DPs. Their reduced sensitivity to identity matches in the presence of other image changes could result from earlier deficits in the perceptual extraction of image-invariant visual identity cues from face images. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Visual event-related potential changes in multiple system atrophy: delayed N2 latency in selective attention to a color task.

PubMed

Kamitani, Toshiaki; Kuroiwa, Yoshiyuki

2009-01-01

Recent studies demonstrated an altered P3 component and prolonged reaction time during the visual discrimination tasks in multiple system atrophy (MSA). In MSA, however, little is known about the N2 component which is known to be closely related to the visual discrimination process. We therefore compared the N2 component as well as the N1 and P3 components in 17 MSA patients with these components in 10 normal controls, by using a visual selective attention task to color or to shape. While the P3 in MSA was significantly delayed in selective attention to shape, the N2 in MSA was significantly delayed in selective attention to color. N1 was normally preserved both in attention to color and in attention to shape. Our electrophysiological results indicate that the color discrimination process during selective attention is impaired in MSA.

Selective maintenance in visual working memory does not require sustained visual attention.

PubMed

Hollingworth, Andrew; Maxcey-Richard, Ashleigh M

2013-08-01

In four experiments, we tested whether sustained visual attention is required for the selective maintenance of objects in visual working memory (VWM). Participants performed a color change-detection task. During the retention interval, a valid cue indicated the item that would be tested. Change-detection performance was higher in the valid-cue condition than in a neutral-cue control condition. To probe the role of visual attention in the cuing effect, on half of the trials, a difficult search task was inserted after the cue, precluding sustained attention on the cued item. The addition of the search task produced no observable decrement in the magnitude of the cuing effect. In a complementary test, search efficiency was not impaired by simultaneously prioritizing an object for retention in VWM. The results demonstrate that selective maintenance in VWM can be dissociated from the locus of visual attention. 2013 APA, all rights reserved

Prevalence of visual impairment in El Salvador: inequalities in educational level and occupational status.

PubMed

Rius, Anna; Guisasola, Laura; Sabidó, Meritxell; Leasher, Janet L; Moriña, David; Villalobos, Astrid; Lansingh, Van C; Mujica, Oscar J; Rivera-Handal, José Eduardo; Silva, Juan Casrlos

2014-11-01

To examine the prevalence of blindness, visual impairment, and related eye diseases and conditions among adults in El Salvador, and to explore socioeconomic inequalities in their prevalence by education level and occupational status, stratified by sex. Based upon the Rapid Assessment of Avoidable Blindness (RAAB) methodology, this nationwide sample comprised 3 800 participants (3 399 examined) ≥ 50 years old from 76 randomly selected clusters of 50 persons each. The prevalence of blindness, visual impairment and related eye diseases and conditions, including uncorrected refractive error (URE), was calculated for categories of education level and occupational status. Multiple logistic regression models were fitted to calculate odds ratios (ORs) and 95% confidence intervals (CIs) and stratified by sex. Age-adjusted prevalence was 2.4% (95% CI: 2.2-2.6) for blindness (men: 2.8% (95% CI: 2.5-3.1); women: 2.2% (95% CI: 1.9-2.5)) and 11.8% (95% CI: 11.6-12.0) for moderate visual impairment (men: 10.8% (95% CI: 10.5-11.1); women: 12.6% (95% CI: 12.4-12.8)). The proportion of visual impairment due to cataract was 43.8% in men and 33.5% in women. Inverse gradients of socioeconomic inequalities were observed in the prevalence of visual impairment. For example, the age-adjusted OR (AOR) was 3.4 (95% CI: 2.0-6.4) for visual impairment and 4.3 (95% CI: 2.1-10.4) for related URE in illiterate women compared to those with secondary education, and 1.9 (95% CI: 1.1-3.1) in cataract in unemployed men. Blindness and visual impairment prevalence is high in the El Salvador adult population. The main associated conditions are cataract and URE, two treatable conditions. As socioeconomic and gender inequalities in ocular health may herald discrimination and important barriers to accessing affordable, good-quality, and timely health care services, prioritization of public eye health care and disability policies should be put in place, particularly among women, the unemployed, and uneducated people.

Number of People Blind or Visually Impaired by Glaucoma Worldwide and in World Regions 1990 – 2010: A Meta-Analysis

PubMed Central

Bourne, Rupert R. A.; Taylor, Hugh R.; Flaxman, Seth R.; Keeffe, Jill; Leasher, Janet; Naidoo, Kovin; Pesudovs, Konrad; White, Richard A.; Wong, Tien Y.; Resnikoff, Serge; Jonas, Jost B.

2016-01-01

Objective To assess the number of individuals visually impaired or blind due to glaucoma and to examine regional differences and temporal changes in this parameter for the period from 1990 to 2012. Methods As part of the Global Burden of Diseases (GBD) Study 2010, we performed a systematic literature review for the period from 1980 to 2012. We primarily identified 14,908 relevant manuscripts, out of which 243 high-quality, population-based studies remained after review by an expert panel that involved application of selection criteria that dwelt on population representativeness and clarity of visual acuity methods used. Sixty-six specified the proportion attributable to glaucoma. The software tool DisMod-MR (Disease Modeling–Metaregression) of the GBD was used to calculate fraction of vision impairment due to glaucoma. Results In 2010, 2.1 million (95% Uncertainty Interval (UI):1.9,2.6) people were blind, and 4.2 (95% UI:3.7,5.8) million were visually impaired due to glaucoma. Glaucoma caused worldwide 6.6% (95% UI:5.9,7.9) of all blindness in 2010 and 2.2% (95% UI:2.0,2.8) of all moderate and severe visual impairment (MSVI). These figures were lower in regions with younger populations (<5% in South Asia) than in high-income regions with relatively old populations (>10%). From 1990 to 2010, the number of blind or visually impaired due to glaucoma increased by 0.8 million (95%UI:0.7, 1.1) or 62% and by 2.3 million (95%UI:2.1,3.5) or 83%, respectively. Percentage of global blindness caused by glaucoma increased between 1990 and 2010 from 4.4% (4.0,5.1) to 6.6%. Age-standardized prevalence of glaucoma related blindness and MSVI did not differ markedly between world regions nor between women. Significance By 2010, one out of 15 blind people was blind due to glaucoma, and one of 45 visually impaired people was visually impaired, highlighting the increasing global burden of glaucoma. PMID:27764086

Number of People Blind or Visually Impaired by Glaucoma Worldwide and in World Regions 1990 - 2010: A Meta-Analysis.

PubMed

Bourne, Rupert R A; Taylor, Hugh R; Flaxman, Seth R; Keeffe, Jill; Leasher, Janet; Naidoo, Kovin; Pesudovs, Konrad; White, Richard A; Wong, Tien Y; Resnikoff, Serge; Jonas, Jost B

2016-01-01

To assess the number of individuals visually impaired or blind due to glaucoma and to examine regional differences and temporal changes in this parameter for the period from 1990 to 2012. As part of the Global Burden of Diseases (GBD) Study 2010, we performed a systematic literature review for the period from 1980 to 2012. We primarily identified 14,908 relevant manuscripts, out of which 243 high-quality, population-based studies remained after review by an expert panel that involved application of selection criteria that dwelt on population representativeness and clarity of visual acuity methods used. Sixty-six specified the proportion attributable to glaucoma. The software tool DisMod-MR (Disease Modeling-Metaregression) of the GBD was used to calculate fraction of vision impairment due to glaucoma. In 2010, 2.1 million (95% Uncertainty Interval (UI):1.9,2.6) people were blind, and 4.2 (95% UI:3.7,5.8) million were visually impaired due to glaucoma. Glaucoma caused worldwide 6.6% (95% UI:5.9,7.9) of all blindness in 2010 and 2.2% (95% UI:2.0,2.8) of all moderate and severe visual impairment (MSVI). These figures were lower in regions with younger populations (<5% in South Asia) than in high-income regions with relatively old populations (>10%). From 1990 to 2010, the number of blind or visually impaired due to glaucoma increased by 0.8 million (95%UI:0.7, 1.1) or 62% and by 2.3 million (95%UI:2.1,3.5) or 83%, respectively. Percentage of global blindness caused by glaucoma increased between 1990 and 2010 from 4.4% (4.0,5.1) to 6.6%. Age-standardized prevalence of glaucoma related blindness and MSVI did not differ markedly between world regions nor between women. By 2010, one out of 15 blind people was blind due to glaucoma, and one of 45 visually impaired people was visually impaired, highlighting the increasing global burden of glaucoma.

Reading impairment in schizophrenia: dysconnectivity within the visual system.

PubMed

Vinckier, Fabien; Cohen, Laurent; Oppenheim, Catherine; Salvador, Alexandre; Picard, Hernan; Amado, Isabelle; Krebs, Marie-Odile; Gaillard, Raphaël

2014-01-01

Patients with schizophrenia suffer from perceptual visual deficits. It remains unclear whether those deficits result from an isolated impairment of a localized brain process or from a more diffuse long-range dysconnectivity within the visual system. We aimed to explore, with a reading paradigm, the functioning of both ventral and dorsal visual pathways and their interaction in schizophrenia. Patients with schizophrenia and control subjects were studied using event-related functional MRI (fMRI) while reading words that were progressively degraded through word rotation or letter spacing. Reading intact or minimally degraded single words involves mainly the ventral visual pathway. Conversely, reading in non-optimal conditions involves both the ventral and the dorsal pathway. The reading paradigm thus allowed us to study the functioning of both pathways and their interaction. Behaviourally, patients with schizophrenia were selectively impaired at reading highly degraded words. While fMRI activation level was not different between patients and controls, functional connectivity between the ventral and dorsal visual pathways increased with word degradation in control subjects, but not in patients. Moreover, there was a negative correlation between the patients' behavioural sensitivity to stimulus degradation and dorso-ventral connectivity. This study suggests that perceptual visual deficits in schizophrenia could be related to dysconnectivity between dorsal and ventral visual pathways. © 2013 Published by Elsevier Ltd.

The utilization and barriers of Pap smear among women with visual impairment.

PubMed

Fang, Wen-Hui; Yen, Chia-Feng; Hu, Jung; Lin, Jin-Ding; Loh, Ching-Hui

2016-04-12

Many evidences illustrate that the Pap smear screening successfully reduces if the cervical cancer could be detected and treated sufficiently early. People with disability were higher comorbidity prevalence, and less likely to use preventive health care and health promotion activities. There were also to demonstrate that people with visual impairment has less access to appropriate healthcare services and is less likely to receive screening examinations. In Taiwan, there was no study to explore utilization of Pap smear, associated factors and use barriers about Pap smear screening test among women with visual impairment. The purpose is to explore the utilization and barriers of using Pap smear for women with visual impairment in Taiwan. To identify the barriers of women with visual from process of receiving Pap smear screening test. The cross-sectional study was conducted and the totally 316 participators were selected by stratified proportional and random sampling from 15 to 64 year old women with visual impairment who lived in Taipei County during December 2009 to January 2010. The data was been collected by phone interview and the interviewers were well trained before interview. The mean age was 47.1 years old and the highest percentage of disabled severity was mile (40.2 %). Totally, 66.5 % of participators were ever using Pap smear and 38.9 % used it during pass 1 year. Their first time to accept Pap smear was 38.8 year old. There was near 50 % of them not to be explained by professionals before accepting the Pap smear. For non-using cases, the top two percentage of barriers were "feel still younger" (22.3 %), the second was "there's no sexual experience" (21.4 %). We found the gynecology experiences was key factor for women with visual impairment to use Pap smear, especially the experiences was during 1 year (OR = 4). Associated factors and barriers to receive Pap smear screening test for women with visual impairment can be addressed through interventions aimed at improving on cognitions and attitudes for cervical cancer risk factors. Our study would be as a reference resource for erasing the barriers and inequality among the visually disabled women.

Visual agnosia and focal brain injury.

PubMed

Martinaud, O

Visual agnosia encompasses all disorders of visual recognition within a selective visual modality not due to an impairment of elementary visual processing or other cognitive deficit. Based on a sequential dichotomy between the perceptual and memory systems, two different categories of visual object agnosia are usually considered: 'apperceptive agnosia' and 'associative agnosia'. Impaired visual recognition within a single category of stimuli is also reported in: (i) visual object agnosia of the ventral pathway, such as prosopagnosia (for faces), pure alexia (for words), or topographagnosia (for landmarks); (ii) visual spatial agnosia of the dorsal pathway, such as cerebral akinetopsia (for movement), or orientation agnosia (for the placement of objects in space). Focal brain injuries provide a unique opportunity to better understand regional brain function, particularly with the use of effective statistical approaches such as voxel-based lesion-symptom mapping (VLSM). The aim of the present work was twofold: (i) to review the various agnosia categories according to the traditional visual dual-pathway model; and (ii) to better assess the anatomical network underlying visual recognition through lesion-mapping studies correlating neuroanatomical and clinical outcomes. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Lrit1, a Retinal Transmembrane Protein, Regulates Selective Synapse Formation in Cone Photoreceptor Cells and Visual Acuity.

PubMed

Ueno, Akiko; Omori, Yoshihiro; Sugita, Yuko; Watanabe, Satoshi; Chaya, Taro; Kozuka, Takashi; Kon, Tetsuo; Yoshida, Satoyo; Matsushita, Kenji; Kuwahara, Ryusuke; Kajimura, Naoko; Okada, Yasushi; Furukawa, Takahisa

2018-03-27

In the vertebrate retina, cone photoreceptors play crucial roles in photopic vision by transmitting light-evoked signals to ON- and/or OFF-bipolar cells. However, the mechanisms underlying selective synapse formation in the cone photoreceptor pathway remain poorly understood. Here, we found that Lrit1, a leucine-rich transmembrane protein, localizes to the photoreceptor synaptic terminal and regulates the synaptic connection between cone photoreceptors and cone ON-bipolar cells. Lrit1-deficient retinas exhibit an aberrant morphology of cone photoreceptor pedicles, as well as an impairment of signal transmission from cone photoreceptors to cone ON-bipolar cells. Furthermore, we demonstrated that Lrit1 interacts with Frmpd2, a photoreceptor scaffold protein, and with mGluR6, an ON-bipolar cell-specific glutamate receptor. Additionally, Lrit1-null mice showed visual acuity impairments in their optokinetic responses. These results suggest that the Frmpd2-Lrit1-mGluR6 axis regulates selective synapse formation in cone photoreceptors and is essential for normal visual function. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Selective attention impairments in Alzheimer's disease: evidence for dissociable components.

PubMed

Levinoff, Elise J; Li, Karen Z H; Murtha, Susan; Chertkow, Howard

2004-07-01

Tasks emphasizing 3 different aspects of selective attention-inhibition, visuospatial selective attention, and decision making-were administered to subjects with mild Alzheimer's disease (AD) and to healthy elderly control (HEC) subjects to determine which components of selective attention were impaired in AD subjects and whether selective attention could be dissociated into different components. The tasks were administered with easy versus hard levels of difficulty to assess proportional slowing as the key variable across tasks. The results indicated that the inhibitory and visual search tasks showed greater proportional slowing in subjects with AD than in HEC subjects, and that the task involving inhibition was significantly more affected in subjects with AD. Furthermore, there were no significant intertask correlations, and the results cannot be explained simply in terms of generalized cognitive slowing. These results provide evidence that inhibition is the most strikingly affected aspect of selective attention that is observed to be impaired in early stages of AD.

Déjà vu in unilateral temporal-lobe epilepsy is associated with selective familiarity impairments on experimental tasks of recognition memory.

PubMed

Martin, Chris B; Mirsattari, Seyed M; Pruessner, Jens C; Pietrantonio, Sandra; Burneo, Jorge G; Hayman-Abello, Brent; Köhler, Stefan

2012-11-01

In déjà vu, a phenomenological impression of familiarity for the current visual environment is experienced with a sense that it should in fact not feel familiar. The fleeting nature of this phenomenon in daily life, and the difficulty in developing experimental paradigms to elicit it, has hindered progress in understanding déjà vu. Some neurological patients with temporal-lobe epilepsy (TLE) consistently experience déjà vu at the onset of their seizures. An investigation of such patients offers a unique opportunity to shed light on its possible underlying mechanisms. In the present study, we sought to determine whether unilateral TLE patients with déjà vu (TLE+) show a unique pattern of interictal memory deficits that selectively affect familiarity assessment. In Experiment 1, we employed a Remember-Know paradigm for categorized visual scenes and found evidence for impairments that were limited to familiarity-based responses. In Experiment 2, we administered an exclusion task for highly similar categorized visual scenes that placed both recognition processes in opposition. TLE+ patients again displayed recognition impairments, and these impairments spared their ability to engage recollective processes so as to counteract familiarity. The selective deficits we observed in TLE+ patients contrasted with the broader pattern of recognition-memory impairments that was present in a control group of unilateral patients without déjà vu (TLE-). MRI volumetry revealed that ipsilateral medial temporal structures were less broadly affected in TLE+ than in TLE- patients, with a trend for more focal volume reductions in the rhinal cortices of the TLE+ group. The current findings establish a first empirical link between déjà vu in TLE and processes of familiarity assessment, as defined and measured in current cognitive models. They also reveal a pattern of selectivity in recognition impairments that is rarely observed and, thus, of significant theoretical interest to the memory literature at large. Copyright © 2012 Elsevier Ltd. All rights reserved.

The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Bo; State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing 100101; Xia Jing

Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unitmore » responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.« less

Resolution of Spatial and Temporal Visual Attention in Infants with Fragile X Syndrome

ERIC Educational Resources Information Center

Farzin, Faraz; Rivera, Susan M.; Whitney, David

2011-01-01

Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal-parietal networks of the…

The development of an indoor mobility course for the evaluation of electronic mobility aids for persons who are visually impaired.

PubMed

Roentgen, Uta R; Gelderblom, Gert Jan; de Witte, Luc P

2012-01-01

To develop a suitable mobility course for the assessment of mobility performance as part of a user evaluation of Electronic Mobility Aids (EMA) aimed at obstacle detection and orientation. A review of the literature led to a list of critical factors for the assessment of mobility performance of persons who are visually impaired. Based upon that list, method, test situations, and determining elements were selected and presented to Dutch orientation and mobility experts. Due to expert advice and a pilot study, minor changes were made and the final version was used for the evaluation of two EMA by eight persons who are visually impaired. The results of the literature study are summarized in an overview of critical factors for the assessment of the mobility performance of persons who are visually impaired. Applied to the requirements of the above mentioned user evaluation a replicable indoor mobility course has been described in detail and tested. Based upon evidence from literature an indoor mobility course has been developed, which was sensitive to assess differences in mobility incidents and obstacle detection when using an EMA compared to the regular mobility aid. Experts' opinion confirmed its face and content validity.

Correlation of MRI Visual Scales with Neuropsychological Profile in Mild Cognitive Impairment of Parkinson's Disease.

PubMed

Vasconcellos, Luiz Felipe; Pereira, João Santos; Adachi, Marcelo; Greca, Denise; Cruz, Manuela; Malak, Ana Lara; Charchat-Fichman, Helenice; Spitz, Mariana

2017-01-01

Few studies have evaluated magnetic resonance imaging (MRI) visual scales in Parkinson's disease-Mild Cognitive Impairment (PD-MCI). We selected 79 PD patients and 92 controls (CO) to perform neurologic and neuropsychological evaluation. Brain MRI was performed to evaluate the following scales: Global Cortical Atrophy (GCA), Fazekas, and medial temporal atrophy (MTA). The analysis revealed that both PD groups (amnestic and nonamnestic) showed worse performance on several tests when compared to CO. Memory, executive function, and attention impairment were more severe in amnestic PD-MCI group. Overall analysis of frequency of MRI visual scales by MCI subtype did not reveal any statistically significant result. Statistically significant inverse correlation was observed between GCA scale and Mini-Mental Status Examination (MMSE), Montreal Cognitive Assessment (MoCA), semantic verbal fluency, Stroop test, figure memory test, trail making test (TMT) B, and Rey Auditory Verbal Learning Test (RAVLT). The MTA scale correlated with Stroop test and Fazekas scale with figure memory test, digit span, and Stroop test according to the subgroup evaluated. Visual scales by MRI in MCI should be evaluated by cognitive domain and might be more useful in more severely impaired MCI or dementia patients.

Deficient cortical face-sensitive N170 responses and basic visual processing in schizophrenia.

PubMed

Maher, S; Mashhoon, Y; Ekstrom, T; Lukas, S; Chen, Y

2016-01-01

Face detection, an ability to identify a visual stimulus as a face, is impaired in patients with schizophrenia. It is unclear whether impaired face processing in this psychiatric disorder results from face-specific domains or stems from more basic visual domains. In this study, we examined cortical face-sensitive N170 response in schizophrenia, taking into account deficient basic visual contrast processing. We equalized visual contrast signals among patients (n=20) and controls (n=20) and between face and tree images, based on their individual perceptual capacities (determined using psychophysical methods). We measured N170, a putative temporal marker of face processing, during face detection and tree detection. In controls, N170 amplitudes were significantly greater for faces than trees across all three visual contrast levels tested (perceptual threshold, two times perceptual threshold and 100%). In patients, however, N170 amplitudes did not differ between faces and trees, indicating diminished face selectivity (indexed by the differential responses to face vs. tree). These results indicate a lack of face-selectivity in temporal responses of brain machinery putatively responsible for face processing in schizophrenia. This neuroimaging finding suggests that face-specific processing is compromised in this psychiatric disorder. Copyright © 2015 Elsevier B.V. All rights reserved.

Selective Maintenance in Visual Working Memory Does Not Require Sustained Visual Attention

PubMed Central

Hollingworth, Andrew; Maxcey-Richard, Ashleigh M.

2012-01-01

In four experiments, we tested whether sustained visual attention is required for the selective maintenance of objects in VWM. Participants performed a color change-detection task. During the retention interval, a valid cue indicated the item that would be tested. Change detection performance was higher in the valid-cue condition than in a neutral-cue control condition. To probe the role of visual attention in the cuing effect, on half of the trials, a difficult search task was inserted after the cue, precluding sustained attention on the cued item. The addition of the search task produced no observable decrement in the magnitude of the cuing effect. In a complementary test, search efficiency was not impaired by simultaneously prioritizing an object for retention in VWM. The results demonstrate that selective maintenance in VWM can be dissociated from the locus of visual attention. PMID:23067118

Prevalence of refractive error and visual impairment among rural school-age children of Goro District, Gurage Zone, Ethiopia.

PubMed

Kedir, Jafer; Girma, Abonesh

2014-10-01

Refractive error is one of the major causes of blindness and visual impairment in children; but community based studies are scarce especially in rural parts of Ethiopia. So, this study aims to assess the prevalence of refractive error and its magnitude as a cause of visual impairment among school-age children of rural community. This community-based cross-sectional descriptive study was conducted from March 1 to April 30, 2009 in rural villages of Goro district of Gurage Zone, found south west of Addis Ababa, the capital of Ethiopia. A multistage cluster sampling method was used with simple random selection of representative villages in the district. Chi-Square and t-tests were used in the data analysis. A total of 570 school-age children (age 7-15) were evaluated, 54% boys and 46% girls. The prevalence of refractive error was 3.5% (myopia 2.6% and hyperopia 0.9%). Refractive error was the major cause of visual impairment accounting for 54% of all causes in the study group. No child was found wearing corrective spectacles during the study period. Refractive error was the commonest cause of visual impairment in children of the district, but no measures were taken to reduce the burden in the community. So, large scale community level screening for refractive error should be conducted and integrated with regular school eye screening programs. Effective strategies need to be devised to provide low cost corrective spectacles in the rural community.

Tracking the evolution of crossmodal plasticity and visual functions before and after sight restoration

PubMed Central

Dormal, Giulia; Lepore, Franco; Harissi-Dagher, Mona; Albouy, Geneviève; Bertone, Armando; Rossion, Bruno

2014-01-01

Visual deprivation leads to massive reorganization in both the structure and function of the occipital cortex, raising crucial challenges for sight restoration. We tracked the behavioral, structural, and neurofunctional changes occurring in an early and severely visually impaired patient before and 1.5 and 7 mo after sight restoration with magnetic resonance imaging. Robust presurgical auditory responses were found in occipital cortex despite residual preoperative vision. In primary visual cortex, crossmodal auditory responses overlapped with visual responses and remained elevated even 7 mo after surgery. However, these crossmodal responses decreased in extrastriate occipital regions after surgery, together with improved behavioral vision and with increases in both gray matter density and neural activation in low-level visual regions. Selective responses in high-level visual regions involved in motion and face processing were observable even before surgery and did not evolve after surgery. Taken together, these findings demonstrate that structural and functional reorganization of occipital regions are present in an individual with a long-standing history of severe visual impairment and that such reorganizations can be partially reversed by visual restoration in adulthood. PMID:25520432

Region-Specific Slowing of Alpha Oscillations is Associated with Visual-Perceptual Abilities in Children Born Very Preterm

PubMed Central

Doesburg, Sam M.; Moiseev, Alexander; Herdman, Anthony T.; Ribary, Urs; Grunau, Ruth E.

2013-01-01

Children born very preterm (≤32 weeks gestational age) without major intellectual or neurological impairments often express selective deficits in visual-perceptual abilities. The alterations in neurophysiological development underlying these problems, however, remain poorly understood. Recent research has indicated that spontaneous alpha oscillations are slowed in children born very preterm, and that atypical alpha-mediated functional network connectivity may underlie selective developmental difficulties in visual-perceptual ability in this group. The present study provides the first source-resolved analysis of slowing of spontaneous alpha oscillations in very preterm children, indicating alterations in a distributed set of brain regions concentrated in areas of posterior parietal and inferior temporal regions associated with visual perception, as well as prefrontal cortical regions and thalamus. We also uniquely demonstrate that slowing of alpha oscillations is associated with selective difficulties in visual-perceptual ability in very preterm children. These results indicate that region-specific slowing of alpha oscillations contribute to selective developmental difficulties prevalent in this population. PMID:24298250

Working memory for visual features and conjunctions in schizophrenia.

PubMed

Gold, James M; Wilk, Christopher M; McMahon, Robert P; Buchanan, Robert W; Luck, Steven J

2003-02-01

The visual working memory (WM) storage capacity of patients with schizophrenia was investigated using a change detection paradigm. Participants were presented with 2, 3, 4, or 6 colored bars with testing of both single feature (color, orientation) and feature conjunction conditions. Patients performed significantly worse than controls at all set sizes but demonstrated normal feature binding. Unlike controls, patient WM capacity declined at set size 6 relative to set size 4. Impairments with subcapacity arrays suggest a deficit in task set maintenance: Greater impairment for supercapacity set sizes suggests a deficit in the ability to selectively encode information for WM storage. Thus, the WM impairment in schizophrenia appears to be a consequence of attentional deficits rather than a reduction in storage capacity.

A nationwide population-based survey on visual acuity, near vision, and self-reported visual function in the adult population in Finland.

PubMed

Laitinen, Arja; Koskinen, Seppo; Härkänen, Tommi; Reunanen, Antti; Laatikainen, Leila; Aromaa, Arpo

2005-12-01

To estimate the prevalence rates of habitual visual acuity (VA) levels and visual impairment in Finland and to assess their correlation with self-reported visual function. Cross-sectional population-based study. Subjects were selected randomly from the Finnish population aged 30 years or older. Of 7979 eligible people, 7393 (93%) were interviewed, 6771 (85%) were examined, and 6663 (84%) had distance VA assessed. Participants underwent a home interview and a comprehensive examination including measuring binocular VA for distance and for near with the participants' current spectacles, if any. The level of VA for distance and for near with current spectacle correction. The self-reported capability to read newsprint and television text and the ability to move about without being restricted by reduced vision. The prevalence of good to moderate VA for distance (VA> or =0.5 [> or =20/40]) measured with current spectacles was 95.9%, and 87.4% had a VA level of 0.8 (20/25) or better. The prevalence of habitual visual impairment (VA< or =0.25 [< or =20/80]) was 1.6%, and 0.5% were blind (VA<0.1 [<20/200]). The prevalence of visual impairment increased significantly with age (P<0.001), especially in the age group of 65 to 74 years and upward. There was no gender difference in VA for distance, but decreased near vision (VA< or =0.25 [< or =20/80]) was significantly more common in men than in women (P<0.01). By applying the imputated numbers of visually impaired and blind participants to the Finnish population (approximately 3 million aged 30 years or older), there were approximately 65000 (2.1%) visually impaired and 17000 (0.6%) blind adult persons in the country in 2000. The correlation between self-reported visual ability and measured visual function was moderate but statistically significant (r = 0.27-0.40; P<0.0001). The proportion of people with reading difficulties or who were unable to read newsprint has decreased 7% during the last 2 decades. Functional visual impairment increased with age especially in the age group of 65 to 74 years and upward and was as prevalent in women as in men. The prevalence of people with reading difficulties has decreased considerably since 1980.

Birding: An Introduction to Ornithological Delights for Blind and Physically Handicapped Individuals.

ERIC Educational Resources Information Center

Cylke, Frank Kurt, Ed.

The booklet provides resources for blind and visually handicapped individuals interested in birding as a hobby. It describes a midwestern group of visually impaired birders and discusses the importance and variety of bird sounds. Listed are a selection of recorded and braille books available on birding, sources of commercial recordings of bird…

The functional neuroanatomy of object agnosia: a case study.

PubMed

Konen, Christina S; Behrmann, Marlene; Nishimura, Mayu; Kastner, Sabine

2011-07-14

Cortical reorganization of visual and object representations following neural injury was examined using fMRI and behavioral investigations. We probed the visual responsivity of the ventral visual cortex of an agnosic patient who was impaired at object recognition following a lesion to the right lateral fusiform gyrus. In both hemispheres, retinotopic mapping revealed typical topographic organization and visual activation of early visual cortex. However, visual responses, object-related, and -selective responses were reduced in regions immediately surrounding the lesion in the right hemisphere, and also, surprisingly, in corresponding locations in the structurally intact left hemisphere. In contrast, hV4 of the right hemisphere showed expanded response properties. These findings indicate that the right lateral fusiform gyrus is critically involved in object recognition and that an impairment to this region has widespread consequences for remote parts of cortex. Finally, functional neural plasticity is possible even when a cortical lesion is sustained in adulthood. Copyright © 2011 Elsevier Inc. All rights reserved.

Perceived vision-related quality of life and risk of falling among community living elderly people.

PubMed

Källstrand-Eriksson, Jeanette; Baigi, Amir; Buer, Nina; Hildingh, Cathrine

2013-06-01

Falls and fall injuries among the elderly population are common, since ageing is a risk factor of falling. Today, this is a major problem because the ageing population is increasing. There are predictive factors of falling and visual impairment is one of them. Usually, only visual acuity is considered when measuring visual impairment, and nothing regarding a person's functional visual ability is taken into account. Therefore, the aim of this study was to assess the perceived vision-related quality of life among the community living elderly using the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) and to investigate whether there was any association among vision-related quality of life and falls. There were 212 randomly selected elderly people participating in the study. Our study indicated that the participants had an impaired perceived vision-related health status. General health was the only NEI VFQ-25 variable significantly associated with falls in both men and women. However, among men, near and distance activities, vision-specific social functioning, role difficulties and dependency, color and peripheral vision were related to falls. © 2012 Nordic College of Caring Science.

Impaired integration of object knowledge and visual input in a case of ventral simultanagnosia with bilateral damage to area V4.

PubMed

Leek, E Charles; d'Avossa, Giovanni; Tainturier, Marie-Josèphe; Roberts, Daniel J; Yuen, Sung Lai; Hu, Mo; Rafal, Robert

2012-01-01

This study examines how brain damage can affect the cognitive processes that support the integration of sensory input and prior knowledge during shape perception. It is based on the first detailed study of acquired ventral simultanagnosia, which was found in a patient (M.T.) with posterior occipitotemporal lesions encompassing V4 bilaterally. Despite showing normal object recognition for single items in both accuracy and response times (RTs), and intact low-level vision assessed across an extensive battery of tests, M.T. was impaired in object identification with overlapping figures displays. Task performance was modulated by familiarity: Unlike controls, M.T. was faster with overlapping displays of abstract shapes than with overlapping displays of common objects. His performance with overlapping common object displays was also influenced by both the semantic relatedness and visual similarity of the display items. These findings challenge claims that visual perception is driven solely by feedforward mechanisms and show how brain damage can selectively impair high-level perceptual processes supporting the integration of stored knowledge and visual sensory input.

Lateral interactions and speed of information processing in highly functioning multiple sclerosis patients.

PubMed

Nagy, Helga; Bencsik, Krisztina; Rajda, Cecília; Benedek, Krisztina; Janáky, Márta; Beniczky, Sándor; Kéri, Szabolcs; Vécsei, László

2007-06-01

Visual impairment is a common feature of multiple sclerosis. The aim of this study was to investigate lateral interactions in the visual cortex of highly functioning patients with multiple sclerosis and to compare that with basic visual and neuropsychologic functions. Twenty-two young, visually unimpaired multiple sclerosis patients with minimal symptoms (Expanded Disability Status Scale <2) and 30 healthy controls subjects participated in the study. Lateral interactions were investigated with the flanker task, during which participants were asked to detect the orientation of a low-contrast Gabor patch (vertical or horizontal), flanked with 2 collinear or orthogonal Gabor patches. Stimulus exposure time was 40, 60, 80, and 100 ms. Digit span forward/backward, digit symbol, verbal fluency, and California Verbal Learning Test procedures were used for background neuropsychologic assessment. Results revealed that patients with multiple sclerosis showed intact visual contrast sensitivity and neuropsychologic functions, whereas orientation detection in the orthogonal condition was significantly impaired. At 40-ms exposure time, collinear flankers facilitated the orientation detection performance of the patients resulting in normal performance. In conclusion, the detection of briefly presented, low-contrast visual stimuli was selectively impaired in multiple sclerosis. Lateral interactions between target and flankers robustly facilitated target detection in the patient group.

Manneristic behaviors of visually impaired children.

PubMed

Molloy, Alysha; Rowe, Fiona J

2011-09-01

To review the literature on visual impairment in children in order to determine which manneristic behaviors are associated with visual impairment, and to establish why these behaviors occur and whether severity of visual impairment influences these behaviors. A literature search utilizing PubMed, OVID, Google Scholar, and Web of Knowledge databases was performed. The University of Liverpool ( www.liv.ac.uk/orthoptics/research ) and local library facilities were also searched. The main manneristic or stereotypic behaviors associated with visual impairment are eye-manipulatory behaviors, such as eye poking and rocking. The degree of visual impairment influences the type of behavior exhibited by visually impaired children. Totally blind children are more likely to adopt body and head movements whereas sight-impaired children tend to adopt eye-manipulatory behaviors and rocking. The mannerisms exhibited most frequently are those that provide a specific stimulation to the child. Theories to explain these behaviors include behavioral, developmental, functional, and neurobiological approaches. Although the precise etiology of these behaviors is unknown, it is recognized that each of the theories is useful in providing some explanation of why certain behaviors may occur. The age at which the frequency of these behaviors decreases is associated with the child's increasing development, thus those visually impaired children with additional disabilities, whose development is impaired, are at an increased risk of developing and maintaining these behaviors. Certain manneristic behaviors of the visually impaired child may also help indicate the cause of visual impairment. There is a wide range of manneristic behaviors exhibited by visually impaired children. Some of these behaviors appear to be particularly associated with certain causes of visual impairment or severity of visual impairment, thus they may supply the practitioner with useful information. Further research into the prevalence of these behaviors in the visually impaired child is required in order to provide effective management.

Color vision but not visual attention is altered in migraine.

PubMed

Shepherd, Alex J

2006-04-01

To examine visual search performance in migraine and headache-free control groups and to determine whether reports of selective color vision deficits in migraine occur preattentively. Visual search is a classic technique to measure certain components of visual attention. The technique can be manipulated to measure both preattentive (automatic) and attentive processes. Here, visual search for colored targets was employed to extend earlier reports that the detection or discrimination of colors selective for the short-wavelength sensitive cone photoreceptors in the retina (S or "blue" cones) is impaired in migraine. Visual search performance for small and large color differences was measured in 34 migraine and 34 control participants. Small and large color differences were included to assess attentive and preattentive processing, respectively. In separate conditions, colored stimuli were chosen that would be detected selectively by either the S-, or by the long- (L or "red") and middle (M or "green")-wavelength sensitive cone photoreceptors. The results showed no preattentive differences between the migraine and control groups. For active, or attentive, search, differences between the migraine and control groups occurred for colors detected by the S-cones only, there were no differences for colors detected by the L- and M-cones. The migraine group responded significantly more slowly than the control group for the S-cone colors. The pattern of results indicates that there are no overall differences in search performance between migraine and control groups. The differences found for the S-cone colors are attributed to impaired discrimination of these colors in migraine and not to differences in attention.

Integrating user centered design, universal design and goal, operation, method and selection rules to improve the usability of DAISY player for persons with visual impairments.

PubMed

Huang, Po-Hsin; Chiu, Ming-Chuan

2016-01-01

The Digital Accessible Information SYstem (DAISY) player is an assistive reading tool developed for use by persons with visual impairments. Certain problems have persisted in the operating procedure and interface of DAISY players, especially for their Chinese users. Therefore, the aim of this study was to redesign the DAISY player with increased usability features for use by native Chinese speakers. First, a User Centered Design (UCD) process was employed to analyze the development of the prototype. Next, operation procedures were reorganized according to GOMS (Goals, Operators, Methods, and Selection rules) methodology. Then the user interface was redesigned according to specific Universal Design (UD) principles. Following these revisions, an experiment involving four scenarios was conducted to compare the new prototype to other players, and it was tested by twelve visually impaired participants. Results indicate the prototype had the quickest operating times, the fewest number of operating errors, and the lowest mental workloads of all the compared players, significantly enhancing the prototype's usability. These findings have allowed us to generate suggestions for developing the next generation of DAISY players for people, especially for Chinese audience. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Blindness and cataract surgical services in Atsinanana region, Madagascar.

PubMed

Randrianaivo, Jean-Baptiste; Anholt, R Michele; Tendrisoa, Diarimirindra Lazaharivony; Margiano, Nestor Jean; Courtright, Paul; Lewallen, Susan

2014-01-01

To assess the prevalence and causes of avoidable blindness in Atsinanana Region, Madagascar, with the Rapid Assessment of Avoidable Blindness (RAAB) survey. We analyzed the hospital records to supplement the findings for public health care planning. Only villages within a two-hour walk from a road, about half of the population of Atsinanana was included. Seventy-two villages were selected by population-proportional-to-size sampling. In each village, compact segment sampling was used to select 50 people over age 50 for eye examination using standard RAAB methods. Records at the two hospitals providing cataract surgery in the region were analyzed for information on patients who underwent cataract surgery in 2010. Cataract incidence rate and target cataract surgery rate (CSR) was modeled from age-specific prevalence of cataract. The participation rate was 87% and the sample prevalence of blindness was 1.96%. Cataract was responsible for 64% and 85.7% of blindness and severe visual impairment, respectively. Visual impairment was due to cataract (69.4%) and refractive error (14.1%). There was a strong positive correlation between cataract surgical rate by district and the proportion of people living within 2 hours of a road. There were marked differences in the profiles of the cataract patients at the two facilities. The estimated incidence of cataract at the 6/18 level was 2.4 eyes per 100 people over age 50 per year. Although the survey included only people with reasonable access, the main cause of visual impairment was still cataract. The incidence of cataract is such that it ought to be possible to eliminate it as a cause of visual impairment, but changes in service delivery at hospitals and strategies to improve access will be necessary for this change.

38 CFR 4.75 - General considerations for evaluating visual impairment.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-connected visual impairment of only one eye. Subject to the provisions of 38 CFR 3.383(a), if visual impairment of only one eye is service-connected, the visual acuity of the other eye will be considered to be... visual impairment of one eye. The evaluation for visual impairment of one eye must not exceed 30 percent...

38 CFR 4.75 - General considerations for evaluating visual impairment.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-connected visual impairment of only one eye. Subject to the provisions of 38 CFR 3.383(a), if visual impairment of only one eye is service-connected, the visual acuity of the other eye will be considered to be... visual impairment of one eye. The evaluation for visual impairment of one eye must not exceed 30 percent...

Impact of verbal, Braille text, and tactile oral hygiene awareness instructions on oral health status of visually impaired children.

PubMed

Chowdary, P Brahmanna; Uloopi, K S; Vinay, C; Rao, V Veerabhadra; Rayala, Chandrasekhar

2016-01-01

Visually impaired children face limitations in interacting with the environment, as they cannot see the facial expression of parents, teachers and cannot perceive social behavior. These children are challenged every day in learning basic life skills and maintenance of oral hygiene being one among them. To evaluate the impact of verbal, braille text, and tactile oral hygiene awareness instructions on oral health status of visually impaired children. One hundred and twenty institutionalized visually impaired children aged 6-16 years were selected and divided into three groups (40 children each). Group I: Verbal and tactile, Group II: Verbal and braille, Group III: Verbal, braille, and tactile. Instructions regarding maintenance of good oral hygiene and brushing technique were explained to all the children, and oral health status of these children using plaque index (Silness and Loe) and gingival index (Loe and Silness) was evaluated at 1, 3, and 6 months interval. ANOVA test was used to analyze the intra- and inter-group comparisons and Tukey post-hoc test for multiple group comparisons. Children in all the groups showed reduction in plaque and gingival scores. There was the highest percentage of reduction in plaque scores in Group III (70.6%), and the decrease in gingival scores was the highest in Group II (84%). Severity of dental plaque and gingivitis in visually impaired individuals can be reduced by a controlled and supervised educational program. The combination of all three, i.e., verbal, braille, and tactile mode of oral health educational aids proved to be effective.

Flexible Feature-Based Inhibition in Visual Search Mediates Magnified Impairments of Selection: Evidence from Carry-Over Effects under Dynamic Preview-Search Conditions

ERIC Educational Resources Information Center

Andrews, Lucy S.; Watson, Derrick G.; Humphreys, Glyn W.; Braithwaite, Jason J.

2011-01-01

Evidence for inhibitory processes in visual search comes from studies using preview conditions, where responses to new targets are delayed if they carry a featural attribute belonging to the old distractor items that are currently being ignored--the negative carry-over effect (Braithwaite, Humphreys, & Hodsoll, 2003). We examined whether…

Deletion of the GluA1 AMPA Receptor Subunit Alters the Expression of Short-Term Memory

ERIC Educational Resources Information Center

Sanderson, David J.; Sprengel, Rolf; Seeburg, Peter H.; Bannerman, David M.

2011-01-01

Deletion of the GluA1 AMPA receptor subunit selectively impairs short-term memory for spatial locations. We further investigated this deficit by examining memory for discrete nonspatial visual stimuli in an operant chamber. Unconditioned suppression of magazine responding to visual stimuli was measured in wild-type and GluA1 knockout mice.…

The Effect of Perceptual Load on Attention-Induced Motion Blindness: The Efficiency of Selective Inhibition

ERIC Educational Resources Information Center

Hay, Julia L.; Milders, Maarten M.; Sahraie, Arash; Niedeggen, Michael

2006-01-01

Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target…

Selective Impairment of Living Things and Musical Instruments on a Verbal "Semantic Knowledge Questionnaire" in a Case of Apperceptive Visual Agnosia

ERIC Educational Resources Information Center

Masullo, Carlo; Piccininni, Chiara; Quaranta, Davide; Vita, Maria Gabriella; Gaudino, Simona; Gainotti, Guido

2012-01-01

Semantic memory was investigated in a patient (MR) affected by a severe apperceptive visual agnosia, due to an ischemic cerebral lesion, bilaterally affecting the infero-mesial parts of the temporo-occipital cortices. The study was made by means of a Semantic Knowledge Questionnaire (Laiacona, Barbarotto, Trivelli, & Capitani, 1993), which takes…

Prevalence and causes of low vision and blindness in Baotou

PubMed Central

Zhang, Guisen; Li, Yan; Teng, Xuelong; Wu, Qiang; Gong, Hui; Ren, Fengmei; Guo, Yuxia; Liu, Lei; Zhang, Han

2016-01-01

Abstract The aim of this study was to investigate the prevalence and causes of low vision and blindness in Baotou, Inner Mongolia. A cross-sectional study was carried out. Multistage sampling was used to select samples. The visual acuity was estimated using LogMAR and corrected by pinhole as best-corrected visual acuity. There were 7000 samples selected and 5770 subjects included in this investigation. The overall bilateral prevalence rates of low vision and blindness were 3.66% (95% CI: 3.17–4.14) and 0.99% (95% CI: 0.73–1.24), respectively. The prevalence of bilateral low vision, blindness, and visual impairment increased with age and decreased with education level. The main leading cause of low vision and blindness was cataract. Diabetic retinopathy and age-related macular degeneration were found to be the second leading causes of blindness in Baotou. The low vision and blindness were more prevalent in elderly people and subjects with low education level in Baotou. Cataract was the main cause for visual impairment and more attention should be paid to fundus diseases. In order to prevent blindness, much more eye care programs should be established. PMID:27631267

Prevalence and causes of low vision and blindness in Baotou: A cross-sectional study.

PubMed

Zhang, Guisen; Li, Yan; Teng, Xuelong; Wu, Qiang; Gong, Hui; Ren, Fengmei; Guo, Yuxia; Liu, Lei; Zhang, Han

2016-09-01

The aim of this study was to investigate the prevalence and causes of low vision and blindness in Baotou, Inner Mongolia.A cross-sectional study was carried out. Multistage sampling was used to select samples. The visual acuity was estimated using LogMAR and corrected by pinhole as best-corrected visual acuity.There were 7000 samples selected and 5770 subjects included in this investigation. The overall bilateral prevalence rates of low vision and blindness were 3.66% (95% CI: 3.17-4.14) and 0.99% (95% CI: 0.73-1.24), respectively. The prevalence of bilateral low vision, blindness, and visual impairment increased with age and decreased with education level. The main leading cause of low vision and blindness was cataract. Diabetic retinopathy and age-related macular degeneration were found to be the second leading causes of blindness in Baotou.The low vision and blindness were more prevalent in elderly people and subjects with low education level in Baotou. Cataract was the main cause for visual impairment and more attention should be paid to fundus diseases. In order to prevent blindness, much more eye care programs should be established.

Multi-tool accessibility assessment of government department websites:a case-study with JKGAD.

PubMed

Ismail, Abid; Kuppusamy, K S; Nengroo, Ab Shakoor

2017-08-02

Nature of being accessible to all categories of users is one of the primary factors for enabling the wider reach of the resources published through World Wide Web. The accessibility of websites has been analyzed through W3C guidelines with the help of various tools. This paper presents a multi-tool accessibility assessment of government department websites belonging to the Indian state of Jammu and Kashmir. A comparative analysis of six accessibility tools is also presented with 14 different parameters. The accessibility analysis tools used in this study for analysis are aChecker, Cynthia Says, Tenon, wave, Mauve, and Hera. These tools provide us the results of selected websites accessibility status on Web Content Accessibility Guidelines (WCAG) 1.0 and 2.0. It was found that there are variations in accessibility analysis results when using different accessibility metrics to measure the accessibility of websites. In addition to this, we have identified the guidelines which have frequently been violated. It was observed that there is a need for incorporating the accessibility component features among the selected websites. This paper presents a set of suggestions to improve the accessibility status of these sites so that the information and services provided by these sites shall reach a wider spectrum of audience without any barrier. Implications for rehabilitation The following points indicates that this case study of JKGAD websites comes under Rehabilitation focused on Visually Impaired users. Due to the universal nature of web, it should be accessible to all according to WCAG guidelines framed by World Wide Web Consortium. In this paper we have identified multiple accessibility barriers for persons with visual impairment while browsing the Jammu and Kashmir Government websites. Multi-tool analysis has been done to pin-point the potential barriers for persons with visually Impaired. Usability analysis has been performed to check whether these websites are suitable for persons with visual impairment. We provide some valuable suggestions which can be followed by developers and designers to minimize these potential accessibility barriers.Based on aforementioned key points, this article helps the persons with disability especially Visually Impaired Users to access the web resources better with the implementation of identified suggestions.

Residual effects of ecstasy (3,4-methylenedioxymethamphetamine) on low level visual processes.

PubMed

Murray, Elizabeth; Bruno, Raimondo; Brown, John

2012-03-01

'Ecstasy' (3,4-methylenedioxymethamphetamine) induces impaired functioning in the serotonergic system, including the occipital lobe. This study employed the 'tilt aftereffect' paradigm to operationalise the function of orientation-selective neurons among ecstasy consumers and controls as a means of investigating the role of reduced serotonin on visual orientation processing. The magnitude of the tilt aftereffect reflects the extent of lateral inhibition between orientation-selective neurons and is elicited to both 'real' contours, processed in visual cortex area V1, and illusory contours, processed in V2. The magnitude of tilt aftereffect to both contour types was examined among 19 ecstasy users (6 ecstasy only; 13 ecstasy-plus-cannabis users) and 23 matched controls (9 cannabis-only users; 14 drug-naive). Ecstasy users had a significantly greater tilt magnitude than non-users for real contours (Hedge's g = 0.63) but not for illusory contours (g = 0.20). These findings provide support for literature suggesting that residual effects of ecstasy (and reduced serotonin) impairs lateral inhibition between orientation-selective neurons in V1, which however suggests that ecstasy may not substantially affect this process in V2. Multiple studies have now demonstrated ecstasy-related deficits on basic visual functions, including orientation and motion processing. Such low-level effects may contribute to the impact of ecstasy use on neuropsychological tests of visuospatial function. Copyright © 2012 John Wiley & Sons, Ltd.

Teaching Students with Visual Impairments. Programming for Students with Special Needs. No. 5.

ERIC Educational Resources Information Center

Alberta Dept. of Education, Edmonton. Special Education Branch.

This resource guide offers suggestions and resources to help provide successful school experiences for students who are blind or visually impaired. Individual sections address: (1) the nature of visual impairment, the specific needs and expectations of students with visual impairment, and the educational implications of visual impairment; (2)…

Memory and mood during MDMA intoxication, with and without memantine pretreatment.

PubMed

de Sousa Fernandes Perna, E B; Theunissen, E L; Kuypers, K P C; Heckman, P; de la Torre, R; Farre, M; Ramaekers, J G

2014-12-01

Previous studies have shown that single doses of MDMA can affect mood and impair memory in humans. The neuropharmacological mechanisms involved in MDMA-induced memory impairment are not clear. Memantine, an NMDA and alpha 7 nicotinic acetylcholine (ACh) receptor antagonist, was able to reverse MDMA-induced memory impairment in rats. This study investigated whether treatment with memantine can prevent MDMA-induced memory impairment in humans. 15 subjects participated in a double-blind, placebo controlled, within-subject design. Subjects received both pre-treatment (placebo/memantine 20 mg) (T1) and treatment (placebo/MDMA 75 mg) (T2) on separate test days. T1 preceded T2 by 120 min. Memory function was assessed 90 min after T2 by means of a Visual Verbal Learning Task, a Prospective Memory Task, the Sternberg Memory Task and the Abstract Visual Pattern Learning Task. Profile of Mood State and psychomotor performance were also assessed to control whether MDMA and memantine interactions would selectively pertain to memory or transfer to other domains as well. MDMA significantly impaired performance in the visual verbal learning task and abstract visual pattern learning task. Pre-treatment with memantine did not prevent MDMA-induced memory impairment in these two tasks. Both positive (vigour, arousal, elation) and negative mood effects (anxiety) were increased by MDMA. The responses were not altered by pretreatment with memantine which had no effect on memory or mood when given alone. These preliminary results suggest that memantine does not reverse MDMA-induced memory impairment and mood in humans. This article is part of the Special Issue entitled 'CNS Stimulants'. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cerebral versus Ocular Visual Impairment: The Impact on Developmental Neuroplasticity.

PubMed

Martín, Maria B C; Santos-Lozano, Alejandro; Martín-Hernández, Juan; López-Miguel, Alberto; Maldonado, Miguel; Baladrón, Carlos; Bauer, Corinna M; Merabet, Lotfi B

2016-01-01

Cortical/cerebral visual impairment (CVI) is clinically defined as significant visual dysfunction caused by injury to visual pathways and structures occurring during early perinatal development. Depending on the location and extent of damage, children with CVI often present with a myriad of visual deficits including decreased visual acuity and impaired visual field function. Most striking, however, are impairments in visual processing and attention which have a significant impact on learning, development, and independence. Within the educational arena, current evidence suggests that strategies designed for individuals with ocular visual impairment are not effective in the case of CVI. We propose that this variance may be related to differences in compensatory neuroplasticity related to the type of visual impairment, as well as underlying alterations in brain structural connectivity. We discuss the etiology and nature of visual impairments related to CVI, and how advanced neuroimaging techniques (i.e., diffusion-based imaging) may help uncover differences between ocular and cerebral causes of visual dysfunction. Revealing these differences may help in developing future strategies for the education and rehabilitation of individuals living with visual impairment.

Cerebral versus Ocular Visual Impairment: The Impact on Developmental Neuroplasticity

PubMed Central

Martín, Maria B. C.; Santos-Lozano, Alejandro; Martín-Hernández, Juan; López-Miguel, Alberto; Maldonado, Miguel; Baladrón, Carlos; Bauer, Corinna M.; Merabet, Lotfi B.

2016-01-01

Cortical/cerebral visual impairment (CVI) is clinically defined as significant visual dysfunction caused by injury to visual pathways and structures occurring during early perinatal development. Depending on the location and extent of damage, children with CVI often present with a myriad of visual deficits including decreased visual acuity and impaired visual field function. Most striking, however, are impairments in visual processing and attention which have a significant impact on learning, development, and independence. Within the educational arena, current evidence suggests that strategies designed for individuals with ocular visual impairment are not effective in the case of CVI. We propose that this variance may be related to differences in compensatory neuroplasticity related to the type of visual impairment, as well as underlying alterations in brain structural connectivity. We discuss the etiology and nature of visual impairments related to CVI, and how advanced neuroimaging techniques (i.e., diffusion-based imaging) may help uncover differences between ocular and cerebral causes of visual dysfunction. Revealing these differences may help in developing future strategies for the education and rehabilitation of individuals living with visual impairment. PMID:28082927

Modality specific semantic knowledge loss for unique items.

PubMed

Kartsounis, L D; Shallice, T

1996-03-01

We report the case of a man who, following a major myocardial infarction, suffered anoxia followed by significant event memory impairment. Investigations indicated that his semantic memory for word concepts and object meanings was well preserved. However, he had great difficulty in identifying in the visual (but not verbal) modality historically known people, such as Queen Elizabeth I and Napoleon, and well known world and London landmarks, such as the Parthenon and Buckingham Palace. This selective impairment could not be accounted for in terms of prosopagnosia or high level visual perceptual deficits and we interpret it as a modality specific semantic memory loss for unique objects.

TEACHING EARLY BRAILLE LITERACY SKILLS WITHIN A STIMULUS EQUIVALENCE PARADIGM TO CHILDREN WITH DEGENERATIVE VISUAL IMPAIRMENTS

PubMed Central

Toussaint, Karen A; Tiger, Jeffrey H

2010-01-01

Despite the need for braille literacy, there has been little attempt to systematically evaluate braille-instruction programs. The current study evaluated an instructive procedure for teaching early braille-reading skills with 4 school-aged children with degenerative visual impairments. Following a series of pretests, braille instruction involved providing a sample braille letter and teaching the selection of the corresponding printed letter from a comparison array. Concomitant with increases in the accuracy of this skill, we assessed and captured the formation of equivalence classes through tests of symmetry and transitivity among the printed letters, the corresponding braille letters, and their spoken names. PMID:21119894

Teaching early braille literacy skills within a stimulus equivalence paradigm to children with degenerative visual impairments.

PubMed

Toussaint, Karen A; Tiger, Jeffrey H

2010-01-01

Despite the need for braille literacy, there has been little attempt to systematically evaluate braille-instruction programs. The current study evaluated an instructive procedure for teaching early braille-reading skills with 4 school-aged children with degenerative visual impairments. Following a series of pretests, braille instruction involved providing a sample braille letter and teaching the selection of the corresponding printed letter from a comparison array. Concomitant with increases in the accuracy of this skill, we assessed and captured the formation of equivalence classes through tests of symmetry and transitivity among the printed letters, the corresponding braille letters, and their spoken names.

A Case-Control Study to Assess the Relationship between Poverty and Visual Impairment from Cataract in Kenya, the Philippines, and Bangladesh

PubMed Central

Kuper, Hannah; Polack, Sarah; Eusebio, Cristina; Mathenge, Wanjiku; Wadud, Zakia; Foster, Allen

2008-01-01

Background The link between poverty and health is central to the Millennium Development Goals (MDGs). Poverty can be both a cause and consequence of poor health, but there are few epidemiological studies exploring this complex relationship. The aim of this study was to examine the association between visual impairment from cataract and poverty in adults in Kenya, Bangladesh, and the Philippines. Methods and Findings A population-based case–control study was conducted in three countries during 2005–2006. Cases were persons aged 50 y or older and visually impaired due to cataract (visual acuity < 6/24 in the better eye). Controls were persons age- and sex-matched to the case participants with normal vision selected from the same cluster. Household expenditure was assessed through the collection of detailed consumption data, and asset ownership and self-rated wealth were also measured. In total, 596 cases and 535 controls were included in these analyses (Kenya 142 cases, 75 controls; Bangladesh 216 cases, 279 controls; Philippines 238 cases, 180 controls). Case participants were more likely to be in the lowest quartile of per capita expenditure (PCE) compared to controls in Kenya (odds ratio = 2.3, 95% confidence interval 0.9–5.5), Bangladesh (1.9, 1.1–3.2), and the Philippines (3.1, 1.7–5.7), and there was significant dose–response relationship across quartiles of PCE. These associations persisted after adjustment for self-rated health and social support indicators. A similar pattern was observed for the relationship between cataract visual impairment with asset ownership and self-rated wealth. There was no consistent pattern of association between PCE and level of visual impairment due to cataract, sex, or age among the three countries. Conclusions Our data show that people with visual impairment due to cataract were poorer than those with normal sight in all three low-income countries studied. The MDGs are committed to the eradication of extreme poverty and provision of health care to poor people, and this study highlights the need for increased provision of cataract surgery to poor people, as they are particularly vulnerable to visual impairment from cataract. PMID:19090614

Visual impairment, visual functioning, and quality of life assessments in patients with glaucoma.

PubMed Central

Parrish, R K

1996-01-01

BACKGROUND/PURPOSE: To determine the relation between visual impairment, visual functioning, and the global quality of life in patients with glaucoma. METHODS: Visual impairment, defined with the American Medical Association Guides to the Evaluation of Permanent Impairment; visual functioning, measured with the VF-14 and the Field Test Version of the National Eye Institute-Visual Functioning Questionnaire (NEI-VFQ); and the global quality of life, assessed with the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), were determined in 147 consecutive patients with glaucoma. RESULTS: None of the SF-36 domains demonstrated more than a weak correlation with visual impairment. The VF-14 scores were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual field impairment; vision specific social functioning, near activities, vision specific role difficulties, general vision, vision specific mental health, color vision, and driving were modestly correlated; visual pain was weakly correlated; and two were not significantly correlated. Correcting for visual actuity weakened the strength of the correlation coefficients. CONCLUSIONS: The SF-36 is unlikely to be useful in determining visual impairment in patients with glaucoma. Based on the moderate correlation between visual field impairment and the VF-14 score, this questionnaire may be generalizable to patients with glaucoma. Several of the NEI-VFQ scales correlate with visual field impairment scores in patients with a wide range of glaucomatous damage. PMID:8981717

Key neurological impairments influence function-related group outcomes after stroke.

PubMed

Han, Lu; Law-Gibson, Diane; Reding, Michael

2002-07-01

The function-related group (FRG) classification is based on functional assessment and has been assumed to encompass the effects of different patterns and severity of neurological impairments. This assumption may not be correct. It has been proposed as a means of comparing rehabilitation outcome across institutions. If neurological impairments significantly affect FRG outcome, then higher FRG outcome scores may reflect selection bias favoring patients with fewer neurological impairments rather than better quality of rehabilitation care. The goal of this study was to assess the influence of motor, somatosensory, and hemianopic visual impairments on FRG outcomes after stroke. All 288 consecutive stroke patients discharged in 1999 from an acute rehabilitation hospital were assigned to 1 of 5 FRGs on the basis of their Functional Independence Measure (FIM) mobility subscore and age. Each FRG was also stratified into 1 of 4 cohorts on the basis of the presence or absence of key neurological impairments: motor impairment only (M), motor plus either somatosensory or hemianopic visual impairment (MS/MV), motor plus somatosensory plus hemianopic visual impairment (MSV), and other combinations of impairments. FIM scores were available every 10 days for all patients from admission to discharge. The effect of impairment group on outcome was assessed within each FRG category through repeated-measures analysis of variance to assess differences in serial FIM scores across the 4 impairment groups. The distribution of each of the 4 impairment groups across the 5 FRGs was assessed with chi2 analysis. The numbers of patients in each of the 5 FRGs from the lowest level, FRG-11, to the highest, FRG-15, were as follows: 78 (27%), 47 (16%), 75 (26%), 55 (19%), and 33 (11%). Different neurological impairments were associated with significantly different mean+/-SD discharge FIM scores as follows: for FRG-11, MSV=63+/-16, MS/MV=68+/-19, and M=81+/-13 (P=0.04); for FRG-12, MSV=47+/-14, MS/MV=61+/-12, and M=75+/-11 (P=0.01); and for FRG-13, MSV=79+/-20, MS/MV=85+/-19, and M=96+/-10 (P<0.02). For FRG-14 and FRG-15, those with M impairments had the highest and those with MSV impairments had the lowest discharge FIM scores, but the differences did not reach statistical significance. The chi2 analysis showed a highly significant difference in representation of MSV impairments across FRG-11 through FRG-15 as follows: 35 of 78 (45%), 20 of 47 (43%), 11 of 74 (15%), 4 of 55 (7%), and 2 of 33 (6%). For patients classified as having an M deficit only or other impairment, the results were as follows: 19 of 78 (24%), 15 of 47 (32%), 41 of 75 (55%), 41 of 55 (75%), and 27 of 33 (82%) (chi(2) analysis=78.7, P<0.0001). The presence of motor, somatosensory, and hemianopic visual impairment significantly affects FRG outcome and should be included in future outcome assessment tools. Comparisons of FIM change and efficiency scores across institutions are potentially biased by referral and selection criteria favoring equally dysfunctional but less neurologically impaired individuals.

People, Things, and Places for Young Children. Selecting Toys for Handicapped Children [and] Playgrounds for Exceptional Children: Considering the Options.

ERIC Educational Resources Information Center

Kemnitzer, Ronald B.; Williams, Ronald R.

The two papers focus on methods of selecting toys for handicapped children and options in playground equipment for this population. The qualities of a good toy, such as stimulation and safety, are examined. The author discusses various considerations in selecting toys for different handicaps; for example, toys for visually impaired children should…

Unmet eye care needs among a homeless youth population.

PubMed

Noel, Christopher W; Srivastava, Raman; Lo, Ryan; Berger, Alan; Tehrani, Nasrin; Lichter, Myrna

2016-06-01

To assess the rate of visual impairment and quantify the unmet eye care needs within Toronto's homeless youth community. Prospective and cross sectional. Ninety randomly selected homeless youth aged 16-24 years. From each of 9 participating homeless youth shelters and drop-in centres in Toronto, 10 English-speaking youths between ages 16 and 24 were randomly recruited. Information regarding sociodemographics, medical history, subjective visual acuity, and access to eye care was collected. Comprehensive visual screening and undilated direct fundoscopy were also performed. The median age of participants was 21 years (interquartile range = 19-23 years), and 62.2% were male. Most participants were homeless for less than 5 years (90%) and earning less than $500 monthly (57.8%). Despite 51.1% of participants having previously owned corrective lenses, only 20% of participants currently owned them when assessed/at study time. When analyzing the better-seeing eye, presenting visual acuity was 20/50 or worse in 18.9% (95% CI 10.8%-27.0%) of participants. Pinhole occlusion decreased the number to 2.2% (95% CI 0%-5.3%). The most common cause of visual impairment was uncorrected refractive error. Ocular pathology was observed in 8 participants. Compared to adults, youth have similar functional visual impairment (adults 24.0%, youth 18.9%) but less impairment uncorrectable by pinhole occlusion (adults 11.0%, youth 2.2%) and are less dissatisfied with their vision (adults 70.0%, youths 36.7%). Although a higher proportion of homeless youths have visited an eye specialist in the past year (adults 14.0%; youths 17.8%), neither group is visiting as frequently as the Canadian average (41%) (p < 0.01). Homeless youth have a high prevalence of visual impairment, even when living within a system of universal health insurance. Ongoing vision-screening programs, readily accessible free eye clinics, and particularly low-cost glasses may help address this need. Copyright © 2016 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Object-based attention underlies the rehearsal of feature binding in visual working memory.

PubMed

Shen, Mowei; Huang, Xiang; Gao, Zaifeng

2015-04-01

Feature binding is a core concept in many research fields, including the study of working memory (WM). Over the past decade, it has been debated whether keeping the feature binding in visual WM consumes more visual attention than the constituent single features. Previous studies have only explored the contribution of domain-general attention or space-based attention in the binding process; no study so far has explored the role of object-based attention in retaining binding in visual WM. We hypothesized that object-based attention underlay the mechanism of rehearsing feature binding in visual WM. Therefore, during the maintenance phase of a visual WM task, we inserted a secondary mental rotation (Experiments 1-3), transparent motion (Experiment 4), or an object-based feature report task (Experiment 5) to consume the object-based attention available for binding. In line with the prediction of the object-based attention hypothesis, Experiments 1-5 revealed a more significant impairment for binding than for constituent single features. However, this selective binding impairment was not observed when inserting a space-based visual search task (Experiment 6). We conclude that object-based attention underlies the rehearsal of binding representation in visual WM. (c) 2015 APA, all rights reserved.

Visual habit formation in monkeys with neurotoxic lesions of the ventrocaudal neostriatum

PubMed Central

Fernandez-Ruiz, Juan; Wang, Jin; Aigner, Thomas G.; Mishkin, Mortimer

2001-01-01

Visual habit formation in monkeys, assessed by concurrent visual discrimination learning with 24-h intertrial intervals (ITI), was found earlier to be impaired by removal of the inferior temporal visual area (TE) but not by removal of either the medial temporal lobe or inferior prefrontal convexity, two of TE's major projection targets. To assess the role in this form of learning of another pair of structures to which TE projects, namely the rostral portion of the tail of the caudate nucleus and the overlying ventrocaudal putamen, we injected a neurotoxin into this neostriatal region of several monkeys and tested them on the 24-h ITI task as well as on a test of visual recognition memory. Compared with unoperated monkeys, the experimental animals were unaffected on the recognition test but showed an impairment on the 24-h ITI task that was highly correlated with the extent of their neostriatal damage. The findings suggest that TE and its projection areas in the ventrocaudal neostriatum form part of a circuit that selectively mediates visual habit formation. PMID:11274442

Age-Related Eye Diseases and Visual Impairment Among U.S. Adults

PubMed Central

Chou, Chiu-Fang; Cotch, Mary Frances; Vitale, Susan; Zhang, Xinzhi; Klein, Ronald; Friedman, David S.; Klein, Barbara E.K.; Saaddine, Jinan B.

2014-01-01

Background Visual impairment is a common health-related disability in the U.S. The association between clinical measurements of age-related eye diseases and visual impairment in data from a national survey has not been reported. Purpose To examine common eye conditions and other correlates associated with visual impairment in the U.S. Methods Data from the 2005–2008 National Health and Nutrition Examination Survey of 5222 Americans aged ≥40 years were analyzed in 2012 for visual impairment (presenting distance visual acuity worse than 20/40 in the better-seeing eye), and visual impairment not due to refractive error (distance visual acuity worse than 20/40 after refraction). Diabetic retinopathy (DR) and age-related macular degeneration (AMD) were assessed from retinal fundus images; glaucoma was assessed from two successive frequency-doubling tests and a cup-to-disc ratio measurement. Results Prevalence of visual impairment and of visual impairment not due to refractive error was 7.5% (95% CI=6.9%, 8.1%) and 2.0% (1.7%, 2.3%), respectively. The prevalence of visual impairment not due to refractive error was significantly higher among people with AMD (2.2%) compared to those without AMD (0.8%), or with DR (3.5%) compared to those without DR (1.2%). Independent predictive factors of visual impairment not due to refractive error were AMD (OR=4.52, 95% CI=2.50, 8.17); increasing age (OR=1.09 per year, 95% CI=1.06, 1.13); and less than a high school education (OR=2.99, 95% CI=1.18, 7.55). Conclusions Visual impairment is a public health problem in the U.S. Visual impairment in two thirds of adults could be eliminated with refractive correction. Screening of the older population may identify adults at increased risk of visual impairment due to eye diseases. PMID:23790986

Stimulus Similarity and Encoding Time Influence Incidental Recognition Memory in Adult Monkeys with Selective Hippocampal Lesions

ERIC Educational Resources Information Center

Zeamer, Alyson; Meunier, Martine; Bachevalier, Jocelyne

2011-01-01

Recognition memory impairment after selective hippocampal lesions in monkeys is more profound when measured with visual paired-comparison (VPC) than with delayed nonmatching-to-sample (DNMS). To clarify this issue, we assessed the impact of stimuli similarity and encoding duration on the VPC performance in monkeys with hippocampal lesions and…

Monocular and binocular visual impairment in the UK Biobank study: prevalence, associations and diagnoses.

PubMed

McKibbin, Martin; Farragher, Tracey M; Shickle, Darren

2018-01-01

To determine the prevalence of, associations with and diagnoses leading to mild visual impairment or worse (logMAR >0.3) in middle-aged adults in the UK Biobank study. Prevalence estimates for monocular and binocular visual impairment were determined for the UK Biobank participants with fundus photographs and spectral domain optical coherence tomography images. Associations with socioeconomic, biometric, lifestyle and medical variables were investigated for cases with visual impairment and matched controls, using multinomial logistic regression models. Self-reported eye history and image grading results were used to identify the primary diagnoses leading to visual impairment for a sample of 25% of cases. For the 65 033 UK Biobank participants, aged 40-69 years and with fundus images, 6682 (10.3%) and 1677 (2.6%) had mild visual impairment or worse in one or both eyes, respectively. Increasing deprivation, age and ethnicity were independently associated with both monocular and binocular visual impairment. No primary diagnosis for the recorded level of visual impairment could be identified for 49.8% of eyes. The most common identifiable diagnoses leading to visual impairment were cataract, amblyopia, uncorrected refractive error and vitreoretinal interface abnormalities. The prevalence of visual impairment in the UK Biobank study cohort is lower than for population-based studies from other industrialised countries. Monocular and binocular visual impairment are associated with increasing deprivation, age and ethnicity. The UK Biobank dataset does not allow confident identification of the causes of visual impairment, and the results may not be applicable to the wider UK population.

Monocular and binocular visual impairment in the UK Biobank study: prevalence, associations and diagnoses

PubMed Central

Farragher, Tracey M; Shickle, Darren

2018-01-01

Objective To determine the prevalence of, associations with and diagnoses leading to mild visual impairment or worse (logMAR >0.3) in middle-aged adults in the UK Biobank study. Methods and analysis Prevalence estimates for monocular and binocular visual impairment were determined for the UK Biobank participants with fundus photographs and spectral domain optical coherence tomography images. Associations with socioeconomic, biometric, lifestyle and medical variables were investigated for cases with visual impairment and matched controls, using multinomial logistic regression models. Self-reported eye history and image grading results were used to identify the primary diagnoses leading to visual impairment for a sample of 25% of cases. Results For the 65 033 UK Biobank participants, aged 40–69 years and with fundus images, 6682 (10.3%) and 1677 (2.6%) had mild visual impairment or worse in one or both eyes, respectively. Increasing deprivation, age and ethnicity were independently associated with both monocular and binocular visual impairment. No primary diagnosis for the recorded level of visual impairment could be identified for 49.8% of eyes. The most common identifiable diagnoses leading to visual impairment were cataract, amblyopia, uncorrected refractive error and vitreoretinal interface abnormalities. Conclusions The prevalence of visual impairment in the UK Biobank study cohort is lower than for population-based studies from other industrialised countries. Monocular and binocular visual impairment are associated with increasing deprivation, age and ethnicity. The UK Biobank dataset does not allow confident identification of the causes of visual impairment, and the results may not be applicable to the wider UK population. PMID:29657974

Image enhancement of real-time television to benefit the visually impaired.

PubMed

Wolffsohn, James S; Mukhopadhyay, Ditipriya; Rubinstein, Martin

2007-09-01

To examine the use of real-time, generic edge detection, image processing techniques to enhance the television viewing of the visually impaired. Prospective, clinical experimental study. One hundred and two sequential visually impaired (average age 73.8 +/- 14.8 years; 59% female) in a single center optimized a dynamic television image with respect to edge detection filter (Prewitt, Sobel, or the two combined), color (red, green, blue, or white), and intensity (one to 15 times) of the overlaid edges. They then rated the original television footage compared with a black-and-white image displaying the edges detected and the original television image with the detected edges overlaid in the chosen color and at the intensity selected. Footage of news, an advertisement, and the end of program credits were subjectively assessed in a random order. A Prewitt filter was preferred (44%) compared with the Sobel filter (27%) or a combination of the two (28%). Green and white were equally popular for displaying the detected edges (32%), with blue (22%) and red (14%) less so. The average preferred edge intensity was 3.5 +/- 1.7 times. The image-enhanced television was significantly preferred to the original (P < .001), which in turn was preferred to viewing the detected edges alone (P < .001) for each of the footage clips. Preference was not dependent on the condition causing visual impairment. Seventy percent were definitely willing to buy a set-top box that could achieve these effects for a reasonable price. Simple generic edge detection image enhancement options can be performed on television in real-time and significantly enhance the viewing of the visually impaired.

Cell Phones, Tablets, and Other Mobile Technology for Users with Visual Impairments

MedlinePlus

... Visual Impairments Cell Phones, Tablets, and Other Mobile Technology for Users with Visual Impairments The Mobile Revolution ... 223 Likes) Cell Phones, Tablets, and Other Mobile Technology Touchscreen Smartphone Accessibility for People with Visual Impairments ...

The mental health of UK ex-servicemen with a combat-related or a non-combat-related visual impairment: does the cause of visual impairment matter?

PubMed

Stevelink, Sharon A M; Malcolm, Estelle M; Gill, Pashyca C; Fear, Nicola T

2015-08-01

Since the start of the conflicts in Iraq and Afghanistan, the numbers of young service personnel who have sustained a combat-related visual impairment have increased. This cross-sectional study examined the mental well-being of ex-servicemen (aged 22-55 years) with a visual impairment and determined if the mental health of those with a combat-related visual impairment differed from those whose visual impairment is not combat-related. Male ex-service personnel with a visual impairment completed a telephone interview assessing the presence of depressive symptomatology, probable anxiety disorder, post-traumatic stress disorder (PTSD) symptomatology and alcohol misuse. Data were analysed using descriptive statistics. 77 participants were included in the study, reflecting a response rate of 76.2%. Of those with complete data (n=74), 20 ex-servicemen had a combat-related visual impairment. Among ex-service personnel with a combat-related visual impairment, 10.0% (95% CI 0 to 23.2) screened positive for a probable depression, 25.0% (95% CI 6.0 to 44.0) for probable anxiety and 10.0% (95% CI 0 to 23.2) for probable PTSD. The prevalence of probable depression and probable PTSD differed among those with a non-combat-related visual impairment, namely 18.5% (95% CI 8.1 to 28.9) and 16.7% (95% CI 6.8 to 26.7), respectively. Probable anxiety was 18.5% (95% CI 8.1 to 28.9) among non-combat-related visually impaired ex-service personnel. 45.0% (95% CI 23.2 to 66.8) of combat-related visually impaired personnel reported hazardous drinking, compared with 20.4% (95% CI 9.7 to 31.2) of those with a non-combat-related visual impairment. Mental health problems were prevalent among visually impaired younger ex-servicemen. No statistically significant differences were found in the prevalence of mental health problems among ex-servicemen with a combat-related visual impairment compared with those with a non-combat-related visual impairment. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Vitreoretinal interface abnormalities in middle-aged adults with visual impairment in the UK Biobank study: prevalence, impact on visual acuity and associations.

PubMed

McKibbin, Martin; Farragher, Tracey; Shickle, Darren

2017-01-01

The aim of this study was to determine the prevalence of vitreoretinal interface abnormalities (VRIA), the degree of visual impairment and associations with VRIA among adults, aged 40-69 years, in the UK Biobank study. Colour fundus photographs and spectral domain optical coherence tomography images were graded for 25% of the 8359 UK Biobank participants with mild visual impairment or worse (LogMAR >0.3 or Snellen <6/12) in at least one eye. The prevalence and contribution of VRIA to visual impairment was determined and multinomial logistic regression models were used to investigate association with known risk factors and other predetermined socioeconomic, biometric, lifestyle and medical variables for cases and matched controls. The minimum prevalence of any VRIA was 17.6% and 8.1% in the eyes with and without visual impairment, respectively. VRIA were identified as the primary cause of visual impairment in 3.6% of eyes. Although epiretinal membrane and vitreomacular traction were the most common VRIA, the degree of visual impairment was typically milder with these than with other VRIA. Visual impairment with a VRIA was positively associated with increasing age (relative risk ratio (RRR) 1.22 (95% CI 1.07 to 1.40)), female gender (RRR 1.28; 1.08 to 1.52) and Asian or Asian British ethnicity (RRR 1.60; 1.10 to 2.32). VRIA are common in middle-aged adults in the UK Biobank study, especially in eyes with visual impairment. VRIA were considered to be the primary cause of visual impairment in 3.6% of all eyes with visual impairment, although there was variation in the degree of visual impairment for each type of VRIA.

Vitreoretinal interface abnormalities in middle-aged adults with visual impairment in the UK Biobank study: prevalence, impact on visual acuity and associations

PubMed Central

Farragher, Tracey; Shickle, Darren

2017-01-01

Objective The aim of this study was to determine the prevalence of vitreoretinal interface abnormalities (VRIA), the degree of visual impairment and associations with VRIA among adults, aged 40–69 years, in the UK Biobank study. Methods and analysis Colour fundus photographs and spectral domain optical coherence tomography images were graded for 25% of the 8359 UK Biobank participants with mild visual impairment or worse (LogMAR >0.3 or Snellen <6/12) in at least one eye. The prevalence and contribution of VRIA to visual impairment was determined and multinomial logistic regression models were used to investigate association with known risk factors and other predetermined socioeconomic, biometric, lifestyle and medical variables for cases and matched controls. Results The minimum prevalence of any VRIA was 17.6% and 8.1% in the eyes with and without visual impairment, respectively. VRIA were identified as the primary cause of visual impairment in 3.6% of eyes. Although epiretinal membrane and vitreomacular traction were the most common VRIA, the degree of visual impairment was typically milder with these than with other VRIA. Visual impairment with a VRIA was positively associated with increasing age (relative risk ratio (RRR) 1.22 (95% CI 1.07 to 1.40)), female gender (RRR 1.28; 1.08 to 1.52) and Asian or Asian British ethnicity (RRR 1.60; 1.10 to 2.32). Conclusions VRIA are common in middle-aged adults in the UK Biobank study, especially in eyes with visual impairment. VRIA were considered to be the primary cause of visual impairment in 3.6% of all eyes with visual impairment, although there was variation in the degree of visual impairment for each type of VRIA. PMID:29354705

20 CFR 416.985 - How we evaluate other visual impairments.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false How we evaluate other visual impairments. 416... evaluate other visual impairments. If you are not blind as defined in the law, we will evaluate a visual impairment the same as we evaluate other impairments in determining disability. Although you will not qualify...

The combined effect of visual impairment and cognitive impairment on disability in older people.

PubMed

Whitson, Heather E; Cousins, Scott W; Burchett, Bruce M; Hybels, Celia F; Pieper, Carl F; Cohen, Harvey J

2007-06-01

To determine the risk of disability in individuals with coexisting visual and cognitive impairment and to compare the magnitude of risk associated with visual impairment, cognitive impairment, or the multimorbidity. Prospective cohort. North Carolina. Three thousand eight hundred seventy-eight participants in the North Carolina Established Populations for the Epidemiologic Studies of the Elderly with nonmissing visual status, cognitive status, and disability status data at baseline Short Portable Mental Status Questionnaire (cognitive impairment defined as > or =4 errors), self reported visual acuity (visual impairment defined as inability to see well enough to recognize a friend across the street or to read newspaper print), demographic and health-related variables, disability status (activities of daily living (ADLs), instrumental activities of daily living (IADLs), mobility), death, and time to nursing home placement. Participants with coexisting visual and cognitive impairment were at greater risk of IADL disability (odds ratio (OR)=6.50, 95% confidence interval (CI)=4.34-9.75), mobility disability (OR=4.04, 95% CI=2.49-6.54), ADL disability (OR=2.84, 95% CI=1.87-4.32), and incident ADL disability (OR=3.66, 95%, CI=2.36-5.65). In each case, the estimated OR associated with the multimorbidity was greater than the estimated OR associated with visual or cognitive impairment alone, a pattern that was not observed for other adverse outcomes assessed. No significant interactions were observed between cognitive impairment and visual impairment as predictors of disability status. Individuals with coexisting visual impairment and cognitive impairment are at high risk of disability, with each condition contributing additively to disability risk. Further study is needed to improve functional trajectories in patients with this prevalent multimorbidity. When visual or cognitive impairment is present, efforts to maximize the other function may be beneficial.

Does visual impairment lead to additional disability in adults with intellectual disabilities?

PubMed

Evenhuis, H M; Sjoukes, L; Koot, H M; Kooijman, A C

2009-01-01

This study addresses the question to what extent visual impairment leads to additional disability in adults with intellectual disabilities (ID). In a multi-centre cross-sectional study of 269 adults with mild to profound ID, social and behavioural functioning was assessed with observant-based questionnaires, prior to expert assessment of visual function. With linear regression analysis the percentage of variance, explained by levels of visual function, was calculated for the total population and per ID level. A total of 107/269 participants were visually impaired or blind (WHO criteria). On top of the decrease by ID visual impairment significantly decreased daily living skills, communication & language, recognition/communication. Visual impairment did not cause more self-absorbed and withdrawn behaviour or anxiety. Peculiar looking habits correlated with visual impairment and not with ID. In the groups with moderate and severe ID this effect seems stronger than in the group with profound ID. Although ID alone impairs daily functioning, visual impairment diminishes the daily functioning even more. Timely detection and treatment or rehabilitation of visual impairment may positively influence daily functioning, language development, initiative and persistence, social skills, communication skills and insecure movement.

Selective Attention, Working Memory, and Executive Function as Potential Independent Sources of Cognitive Dysfunction in Schizophrenia.

PubMed

Gold, James M; Robinson, Benjamin; Leonard, Carly J; Hahn, Britta; Chen, Shuo; McMahon, Robert P; Luck, Steven J

2017-11-11

People with schizophrenia demonstrate impairments in selective attention, working memory, and executive function. Given the overlap in these constructs, it is unclear if these represent distinct impairments or different manifestations of one higher-order impairment. To examine this question, we administered tasks from the basic cognitive neuroscience literature to measure visual selective attention, working memory capacity, and executive function in 126 people with schizophrenia and 122 healthy volunteers. Patients demonstrated deficits on all tasks with the exception of selective attention guided by strong bottom-up inputs. Although the measures of top-down control of selective attention, working memory, and executive function were all intercorrelated, several sources of evidence indicate that working memory and executive function are separate sources of variance. Specifically, both working memory and executive function independently contributed to the discrimination of group status and independently accounted for variance in overall general cognitive ability as assessed by the MATRICS battery. These two cognitive functions appear to be separable features of the cognitive impairments observed in schizophrenia. © The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

A novel brain-computer interface based on the rapid serial visual presentation paradigm.

PubMed

Acqualagna, Laura; Treder, Matthias Sebastian; Schreuder, Martijn; Blankertz, Benjamin

2010-01-01

Most present-day visual brain computer interfaces (BCIs) suffer from the fact that they rely on eye movements, are slow-paced, or feature a small vocabulary. As a potential remedy, we explored a novel BCI paradigm consisting of a central rapid serial visual presentation (RSVP) of the stimuli. It has a large vocabulary and realizes a BCI system based on covert non-spatial selective visual attention. In an offline study, eight participants were presented sequences of rapid bursts of symbols. Two different speeds and two different color conditions were investigated. Robust early visual and P300 components were elicited time-locked to the presentation of the target. Offline classification revealed a mean accuracy of up to 90% for selecting the correct symbol out of 30 possibilities. The results suggest that RSVP-BCI is a promising new paradigm, also for patients with oculomotor impairments.

Visual attention in preterm born adults: specifically impaired attentional sub-mechanisms that link with altered intrinsic brain networks in a compensation-like mode.

PubMed

Finke, Kathrin; Neitzel, Julia; Bäuml, Josef G; Redel, Petra; Müller, Hermann J; Meng, Chun; Jaekel, Julia; Daamen, Marcel; Scheef, Lukas; Busch, Barbara; Baumann, Nicole; Boecker, Henning; Bartmann, Peter; Habekost, Thomas; Wolke, Dieter; Wohlschläger, Afra; Sorg, Christian

2015-02-15

Although pronounced and lasting deficits in selective attention have been observed for preterm born individuals it is unknown which specific attentional sub-mechanisms are affected and how they relate to brain networks. We used the computationally specified 'Theory of Visual Attention' together with whole- and partial-report paradigms to compare attentional sub-mechanisms of pre- (n=33) and full-term (n=32) born adults. Resting-state fMRI was used to evaluate both between-group differences and inter-individual variance in changed functional connectivity of intrinsic brain networks relevant for visual attention. In preterm born adults, we found specific impairments of visual short-term memory (vSTM) storage capacity while other sub-mechanisms such as processing speed or attentional weighting were unchanged. Furthermore, changed functional connectivity was found in unimodal visual and supramodal attention-related intrinsic networks. Among preterm born adults, the individual pattern of changed connectivity in occipital and parietal cortices was systematically associated with vSTM in such a way that the more distinct the connectivity differences, the better the preterm adults' storage capacity. These findings provide first evidence for selectively changed attentional sub-mechanisms in preterm born adults and their relation to altered intrinsic brain networks. In particular, data suggest that cortical changes in intrinsic functional connectivity may compensate adverse developmental consequences of prematurity on visual short-term storage capacity. Copyright © 2014 Elsevier Inc. All rights reserved.

Vision-related fitness to drive mobility scooters: A practical driving test.

PubMed

Cordes, Christina; Heutink, Joost; Tucha, Oliver M; Brookhuis, Karel A; Brouwer, Wiebo H; Melis-Dankers, Bart J M

2017-03-06

To investigate practical fitness to drive mobility scooters, comparing visually impaired participants with healthy controls. Between-subjects design. Forty-six visually impaired (13 with very low visual acuity, 10 with low visual acuity, 11 with peripheral field defects, 12 with multiple visual impairment) and 35 normal-sighted controls. Participants completed a practical mobility scooter test-drive, which was recorded on video. Two independent occupational therapists specialized in orientation and mobility evaluated the videos systematically. Approximately 90% of the visually impaired participants passed the driving test. On average, participants with visual impairments performed worse than normal-sighted controls, but were judged sufficiently safe. In particular, difficulties were observed in participants with peripheral visual field defects and those with a combination of low visual acuity and visual field defects. People with visual impairment are, in practice, fit to drive mobility scooters; thus visual impairment on its own should not be viewed as a determinant of safety to drive mobility scooters. However, special attention should be paid to individuals with visual field defects with or without a combined low visual acuity. The use of an individual practical fitness-to-drive test is advised.

Reduced auditory processing capacity during vocalization in children with Selective Mutism.

PubMed

Arie, Miri; Henkin, Yael; Lamy, Dominique; Tetin-Schneider, Simona; Apter, Alan; Sadeh, Avi; Bar-Haim, Yair

2007-02-01

Because abnormal Auditory Efferent Activity (AEA) is associated with auditory distortions during vocalization, we tested whether auditory processing is impaired during vocalization in children with Selective Mutism (SM). Participants were children with SM and abnormal AEA, children with SM and normal AEA, and normally speaking controls, who had to detect aurally presented target words embedded within word lists under two conditions: silence (single task), and while vocalizing (dual task). To ascertain specificity of auditory-vocal deficit, effects of concurrent vocalizing were also examined during a visual task. Children with SM and abnormal AEA showed impaired auditory processing during vocalization relative to children with SM and normal AEA, and relative to control children. This impairment is specific to the auditory modality and does not reflect difficulties in dual task per se. The data extends previous findings suggesting that deficient auditory processing is involved in speech selectivity in SM.

Association of disease-specific causes of visual impairment and 10-year mortality amongst Indigenous Australians: the Central Australian Ocular Health Study.

PubMed

Estevez, José; Kaidonis, Georgia; Henderson, Tim; Craig, Jamie E; Landers, John

2018-01-01

Visual impairment significantly impairs the length and quality of life, but little is known of its impact in Indigenous Australians. To investigate the association of disease-specific causes of visual impairment with all-cause mortality. A retrospective cohort analysis. A total of 1347 Indigenous Australians aged over 40 years. Participants visiting remote medical clinics underwent clinical examinations including visual acuity, subjective refraction and slit-lamp examination of the anterior and posterior segments. The major ocular cause of visual impairment was determined. Patients were assessed periodically in these remote clinics for the succeeding 10 years after recruitment. Mortality rates were obtained from relevant departments. All-cause 10-year mortality and its association with disease-specific causes of visual impairment. The all-cause mortality rate for the entire cohort was 29.3% at the 10-year completion of follow-up. Of those with visual impairment, the overall mortality rate was 44.9%. The mortality rates differed for those with visual impairment due to cataract (59.8%), diabetic retinopathy (48.4%), trachoma (46.6%), 'other' (36.2%) and refractive error (33.4%) (P < 0.0001). Only those with visual impairment from diabetic retinopathy were any more likely to die during the 10 years of follow-up when compared with those without visual impairment (HR 1.70; 95% CI, 1.00-2.87; P = 0.049). Visual impairment was associated with all-cause mortality in a cohort of Indigenous Australians. However, diabetic retinopathy was the only ocular disease that significantly increased the risk of mortality. Visual impairment secondary to diabetic retinopathy may be an important predictor of mortality. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study.

PubMed

Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

2016-01-01

Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was -0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = -0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5-3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment.

Visual artificial grammar learning in dyslexia: A meta-analysis.

PubMed

van Witteloostuijn, Merel; Boersma, Paul; Wijnen, Frank; Rispens, Judith

2017-11-01

Literacy impairments in dyslexia have been hypothesized to be (partly) due to an implicit learning deficit. However, studies of implicit visual artificial grammar learning (AGL) have often yielded null results. The aim of this study is to weigh the evidence collected thus far by performing a meta-analysis of studies on implicit visual AGL in dyslexia. Thirteen studies were selected through a systematic literature search, representing data from 255 participants with dyslexia and 292 control participants (mean age range: 8.5-36.8 years old). If the 13 selected studies constitute a random sample, individuals with dyslexia perform worse on average than non-dyslexic individuals (average weighted effect size=0.46, 95% CI [0.14 … 0.77], p=0.008), with a larger effect in children than in adults (p=0.041; average weighted effect sizes 0.71 [sig.] versus 0.16 [non-sig.]). However, the presence of a publication bias indicates the existence of missing studies that may well null the effect. While the studies under investigation demonstrate that implicit visual AGL is impaired in dyslexia (more so in children than in adults, if in adults at all), the detected publication bias suggests that the effect might in fact be zero. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Psycho acoustical Measures in Individuals with Congenital Visual Impairment.

PubMed

Kumar, Kaushlendra; Thomas, Teenu; Bhat, Jayashree S; Ranjan, Rajesh

2017-12-01

In congenital visual impaired individuals one modality is impaired (visual modality) this impairment is compensated by other sensory modalities. There is evidence that visual impaired performed better in different auditory task like localization, auditory memory, verbal memory, auditory attention, and other behavioural tasks when compare to normal sighted individuals. The current study was aimed to compare the temporal resolution, frequency resolution and speech perception in noise ability in individuals with congenital visual impaired and normal sighted. Temporal resolution, frequency resolution, and speech perception in noise were measured using MDT, GDT, DDT, SRDT, and SNR50 respectively. Twelve congenital visual impaired participants with age range of 18 to 40 years were taken and equal in number with normal sighted participants. All the participants had normal hearing sensitivity with normal middle ear functioning. Individual with visual impairment showed superior threshold in MDT, SRDT and SNR50 as compared to normal sighted individuals. This may be due to complexity of the tasks; MDT, SRDT and SNR50 are complex tasks than GDT and DDT. Visual impairment showed superior performance in auditory processing and speech perception with complex auditory perceptual tasks.

VISUAL ACUITY IN PSEUDOXANTHOMA ELASTICUM.

PubMed

Risseeuw, Sara; Ossewaarde-van Norel, Jeannette; Klaver, Caroline C W; Colijn, Johanna M; Imhof, Saskia M; van Leeuwen, Redmer

2018-04-12

To assess the age-specific proportion of visual impairment in patients with pseudoxanthoma elasticum (PXE) and to compare this with foveal abnormality and similar data of late age-related macular degeneration patients. Cross-sectional data of 195 patients with PXE were reviewed, including best-corrected visual acuity and imaging. The World Health Organisation criteria were used to categorize bilateral visual impairment. These results were compared with similar data of 131 patients with late age-related macular degeneration from the Rotterdam study. Overall, 50 PXE patients (26.0%) were visually impaired, including 21 (11%) with legal blindness. Visual functioning declined with increasing age. In patients older than 50 years, 37% was visually impaired and 15% legally blind. Foveal choroidal neovascularization was found in 84% of eyes with a best-corrected visual acuity lower than 20/70 (0.30) and macular atrophy in the fovea in 16%. In late age-related macular degeneration patients, 40% were visually impaired and 13% legally blind. Visual impairment started approximately 20 years later as compared with PXE patients. Visual impairment and blindness are frequent in PXE, particularly in patients older than 50 years. Although choroidal neovascularization is associated with the majority of vision loss, macular atrophy is also common. The proportion of visual impairment in PXE is comparable with late age-related macular degeneration but manifests earlier in life.

Happy but still focused: failures to find evidence for a mood-induced widening of visual attention.

PubMed

Bruyneel, Lynn; van Steenbergen, Henk; Hommel, Bernhard; Band, Guido P H; De Raedt, Rudi; Koster, Ernst H W

2013-05-01

In models of affect and cognition, it is held that positive affect broadens the scope of attention. Consistent with this claim, previous research has indeed suggested that positive affect is associated with impaired selective attention as evidenced by increased interference of spatially distant distractors. However, several recent findings cast doubt on the reliability of this observation. In the present study, we examined whether selective attention in a visual flanker task is influenced by positive mood induction. Across three experiments, positive affect consistently failed to exert any impact on selective attention. The implications of this null-finding for theoretical models of affect and cognition are discussed.

Evaluating rehabilitation goals of visually impaired children in multidisciplinary care according to ICF-CY guidelines.

PubMed

Rainey, Linda; van Nispen, Ruth; van Rens, Ger

2014-11-01

To gain qualitative insight into the rehabilitation goals of visually impaired children and how these goals relate to the structure of the International Classification of Functioning, Disability and Health (ICF) and patient characteristics. A patient record study was conducted, analysing rehabilitation goals and characteristics of children with a suspected visual impairment in the Netherlands (<18 years) who applied for multidisciplinary services in 2012 (N = 289). Chi-square analyses for trend in rehabilitation content across age bands and additional analyses were performed. The three most common diagnoses were nystagmus (21.2%), cerebral visual impairment (16.2%) and albinism (6.1%). Rehabilitation goals for children aged <7 years were mostly aimed at 'physical (visual) functioning' (36.7%) and 'environmental factors' (36.7%). For children ≥7 years, significantly more goals were identified on activity and participation (A&P) domains (52.2%). Three A and P domains presented a significant linear trend on the number of rehabilitation goals across age bands: (1) 'Learning and applying knowledge' (13.042, p < 0.001), (4) 'Mobility' (31.340, p < 0.001) and (8) 'Major life areas' (5.925, p = 0.015). Regression analysis showed that both age and visual acuity significantly contributed to the number of A and P goals. Although analyses were based on a selection of patient records, the number and nature of rehabilitation goals differ significantly with age. Many A and P goals seem underrepresented at the intake procedure, for example: communication, peer interaction and participating in leisure activities. A systematic, standardized procedure is required to catalogue all existing goals and to be able to evaluate progress and potential new or other important goals. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

The Investigation of Some Physical, Physiological and Anthropometric Parameters of Visually Impaired and Non-Impaired a National Male Judoka

ERIC Educational Resources Information Center

Mayda, Muhammet Hakan; Karakoc, Onder; Ozdal, Mustafa

2016-01-01

It was pointed to analyze some physical, physiological and anthropometric parameters of visually impaired and non-impaired A National male judoka in this study. A total of 14 volunteer A National male judoka, of which 8 were visually impaired (age: 25.12 ± 3.75, disability status: 20-200) and 6 were not visually impaired (age: 21.50 ± 1.51),…

Project F. A. S. T.: Facilitating Academic Study Techniques for Handicapped Children. Volume 2. Final Report.

ERIC Educational Resources Information Center

Martin, Clessen J.

Volume 2, the appendix to the final report of Project FAST, consists of prose selections used to study the effects of text reduction techniques on the comprehension and recall of written materials among visually handicapped and hearing impaired subjects. Each selection is presented in various versions such as 10 percent subjective deleted, 20…

The Nigerian national blindness and visual impairment survey: Rationale, objectives and detailed methodology

PubMed Central

Dineen, Brendan; Gilbert, Clare E; Rabiu, Mansur; Kyari, Fatima; Mahdi, Abdull M; Abubakar, Tafida; Ezelum, Christian C; Gabriel, Entekume; Elhassan , Elizabeth; Abiose, Adenike; Faal, Hannah; Jiya, Jonathan Y; Ozemela, Chinenyem P; Lee, Pak Sang; Gudlavalleti, Murthy VS

2008-01-01

Background Despite having the largest population in Africa, Nigeria has no accurate population based data to plan and evaluate eye care services. A national survey was undertaken to estimate the prevalence and determine the major causes of blindness and low vision. This paper presents the detailed methodology used during the survey. Methods A nationally representative sample of persons aged 40 years and above was selected. Children aged 10–15 years and individuals aged <10 or 16–39 years with visual impairment were also included if they lived in households with an eligible adult. All participants had their height, weight, and blood pressure measured followed by assessment of presenting visual acuity, refractokeratomery, A-scan ultrasonography, visual fields and best corrected visual acuity. Anterior and posterior segments of each eye were examined with a torch and direct ophthalmoscope. Participants with visual acuity of < = 6/12 in one or both eyes underwent detailed examination including applanation tonometry, dilated slit lamp biomicroscopy, lens grading and fundus photography. All those who had undergone cataract surgery were refracted and best corrected vision recorded. Causes of visual impairment by eye and for the individual were determined using a clinical algorithm recommended by the World Health Organization. In addition, 1 in 7 adults also underwent a complete work up as described for those with vision < = 6/12 for constructing a normative data base for Nigerians. Discussion The field work for the study was completed in 30 months over the period 2005–2007 and covered 305 clusters across the entire country. Concurrently persons 40+ years were examined to form a normative data base. Analysis of the data is currently underway. Conclusion The methodology used was robust and adequate to provide estimates on the prevalence and causes of blindness in Nigeria. The survey would also provide information on barriers to accessing services, quality of life of visually impaired individuals and also provide normative data for Nigerian eyes. PMID:18808712

Visual impairment and depression among socially vulnerable older adults in Armenia.

PubMed

Giloyan, Aida; Harutyunyan, Tsovinar; Petrosyan, Varduhi

2015-01-01

Visual impairment in older adults is a major public health problem. Untreated visual impairment might negatively impact physical and psychological health. This study assessed the association between visual impairment and depression among socially vulnerable older adults (those aged 50 and above) in Armenia. The survey and eye screenings were carried out among 339 participants who were the residents of retirement homes and single older adults in the households. The study team used Golovin-Sivtsev chart and cycloplegic skiascopy to measure visual impairment and Center for Epidemiologic Studies Depression scale to measure depression. The prevalence of visual impairment in the sample was 13.3%. Almost 24.0% of participants reported depression symptoms. Participants living in the retirement homes had substantially higher rates of visual impairment (21.5%) and depression (28.0%) than those living in households (9.3% and 15.0%, respectively). The odds of having depression were higher among those with visual impairment compared to those without after adjusting for confounders (OR = 2.75; 95% CI: 1.29-5.87). Having at least one non-communicable disease was associated with depression (OR = 2.47; 95% CI: 1.28-4.75). Living in the retirement home was marginally significantly associated with having depression. Other confounders included age, gender, education, physical activity, and smoking. Visual impairment was significantly associated with depression in socially vulnerable older adults in Armenia. Timely eye screenings in similar population groups could lead to early detection of visual impairment and prevention of visual loss and associated mental health problems.

Prevalence and Causes of Visual Impairment in Fundong District, North West Cameroon: Results of a Population-Based Survey.

PubMed

Oye, Joseph; Mactaggart, Islay; Polack, Sarah; Schmidt, Elena; Tamo, Violet; Okwen, Marvice; Kuper, Hannah

2017-12-01

To estimate the prevalence and causes of visual impairment in Fundong Health District, North West Cameroon. A total of 51 clusters of 80 people (all ages) were sampled with probability proportionate to size and compact segment sampling. Visual acuity (VA) was measured with a tumbling "E" chart. An ophthalmic nurse examined people with VA<6/18 in either eye. The presence of hearing and physical impairments were assessed using clinical examination, and self-reported visual problems using the Washington Group Short Set. In total, 4080 people were enumerated of whom 3567 were screened (response rate 87%). The overall prevalence of visual impairment was 2.3% (95% CI 1.8-3.0%) and blindness was 0.6% (0.3-1.0%). The prevalence of both blindness and visual impairment increased rapidly with age, so that the vast majority of cases of visual impairment (84%) and blindness (82%) were in people aged 50+. Posterior segment disease and cataract were the main causes of blindness and visual impairment, with refractive error also an important cause of visual impairment. Cataract surgical coverage (proportion of all cataracts that had received surgery) was relatively high (87% of people at VA<6/60). Post-surgery outcomes were poor, with 31% of operated eyes having VA<6/60. Among the 82 people with visual impairment, 22% had a physical impairment or epilepsy and 30% had a hearing impairment. Self-reported difficulties in vision were relatively closely related to clinical measures of visual impairment. Ophthalmic programmes in Cameroon need to incorporate control of posterior segment diseases while also working to improve outcomes after cataract surgery.

Exploring the patient perspective of fatigue in adults with visual impairment: a qualitative study

PubMed Central

Bode, Christina; van der Aa, Hilde P A; Hulshof, Carel T J; Bosmans, Judith E; van Rens, Gerardus H M B; van Nispen, Ruth M A

2017-01-01

Objectives Fatigue is an often mentioned symptom by patients with irreversible visual impairment. This study explored the patient perspective of fatigue in visually impaired adults with a focus on symptoms of fatigue, causes, consequences and coping strategies. Setting Two large Dutch low vision multidisciplinary rehabilitation organisations. Participants 16 visually impaired adults with severe symptoms of fatigue selected by purposive sampling. Methods A qualitative study involving semistructured interviews. A total of four first-level codes were top–down predetermined in correspondence with the topics of the research question. Verbatim transcribed interviews were analysed with a combination of a deductive and inductive approach using open and axial coding. Results Participants often described the symptoms of fatigue as a mental, daily and physical experience. The most often mentioned causes of fatigue were a high cognitive load, the intensity and amount of activities, the high effort necessary to establish visual perception, difficulty with light intensity and negative cognitions. Fatigue had the greatest impact on the ability to carry out social roles and participation, emotional functioning and cognitive functioning. The most common coping strategies were relaxation, external support, socialising and physical exercise and the acceptance of fatigue. Conclusions Our results indicate that low vision-related fatigue is mainly caused by population specific determinants that seem different from the fatigue experience described in studies with other patient populations. Fatigue may be central to the way patients react, adapt and compensate to the consequences of vision loss. These findings indicate a need for future research aimed at interventions specifically tailored to the unique aspects of fatigue related to vision loss. PMID:28775181

Special Problems of People with Diabetes and Visual Impairment.

ERIC Educational Resources Information Center

Rosenthal, J. L.

1993-01-01

This article addresses the types of visual impairment caused by diabetes and the unique problems that people with diabetes and visual impairment face. Diabetic retinopathy, cataracts, glaucoma, and diabetic optic neuropathy are discussed as causes of visual impairment, and specific problems in basic living are identified, including diet,…

Clothing Construction: An Instructional Package with Adaptations for Visually Impaired Individuals.

ERIC Educational Resources Information Center

Crawford, Glinda B.; And Others

Developed for the home economics teacher of mainstreamed visually impaired students, this guide provides clothing instruction lesson plans for the junior high level. First, teacher guidelines are given, including characteristics of the visually impaired, orienting such students to the classroom, orienting class members to the visually impaired,…

Attentional Processes in Young Children with Congenital Visual Impairment

ERIC Educational Resources Information Center

Tadic, Valerie; Pring, Linda; Dale, Naomi

2009-01-01

The study investigated attentional processes of 32 preschool children with congenital visual impairment (VI). Children with profound visual impairment (PVI) and severe visual impairment (SVI) were compared to a group of typically developing sighted children in their ability to respond to adult directed attention in terms of establishing,…

The Relationship between Visual Impairment and Gestures.

ERIC Educational Resources Information Center

Frame, Melissa J.

2000-01-01

A study found the gestural activity of 15 adolescents with visual impairments differed from that of 15 adolescents with sight. Subjects with visual impairments used more adapters (especially finger-to-hand gestures) and fewer conversational gestures. Differences in gestural activity by degree of visual impairment and grade in school were also…

[Individual differences in sense of direction and psychological stress associated with mobility in visually impaired people].

PubMed

Matsunaka, Kumiko; Shibata, Yuki; Yamamoto, Toshikazu

2008-08-01

Study 1 investigated individual differences in spatial cognition amongst visually impaired students and sighted controls, as well as the extent to which visual status contributes to these individual differences. Fifty-eight visually impaired and 255 sighted university students evaluated their sense of direction via self-ratings. Visual impairment contributed to the factors associated with the use and understanding of maps, confirming that maps are generally unfamiliar to visually impaired people. The relationship between psychological stress associated with mobility and individual differences in sense of direction was investigated in Study 2. A stress checklist was administered to the 51 visually impaired students who participated in Study 1. Psychological stress level was related to understanding and use of maps, as well as orientation and renewal, that is, course correction after being got lost. Central visual field deficits were associated with greater mobility-related stress levels than peripheral visual field deficits.

Visual impairment in children and adolescents in Norway.

PubMed

Haugen, Olav H; Bredrup, Cecilie; Rødahl, Eyvind

2016-06-01

BACKGROUND Due to failures in reporting and poor data security, the Norwegian Registry of Blindness was closed down in 1995. Since that time, no registration of visual impairment has taken place in Norway. All the other Nordic countries have registries for children and adolescents with visual impairment. The purpose of this study was to survey visual impairments and their causes in children and adolescents, and to assess the need for an ophthalmic registry.MATERIAL AND METHOD Data were collected via the county teaching centres for the visually impaired in the period from 2005 - 2010 on children and adolescents aged less than 20 years with impaired vision (n = 628). This was conducted as a point prevalence study as of 1 January 2004. Visual function, ophthalmological diagnosis, systemic diagnosis and additional functional impairments were recorded.RESULTS Approximately two-thirds of children and adolescents with visual impairment had reduced vision, while one-third were blind. The three largest diagnostic groups were neuro-ophthalmic diseases (37 %), retinal diseases (19 %) and conditions affecting the eyeball in general (14 %). The prevalence of additional functional impairments was high, at 53 %, most often in the form of motor problems or cognitive impairments.INTERPRETATION The results of the study correspond well with similar investigations in the other Nordic countries. Our study shows that the registries associated with teaching for the visually impaired are inadequate in terms of medical data, and this underlines the need for an ophthalmic registry of children and adolescents with visual impairment.

The risk of newly developed visual impairment in treated normal-tension glaucoma: 10-year follow-up.

PubMed

Choi, Yun Jeong; Kim, Martha; Park, Ki Ho; Kim, Dong Myung; Kim, Seok Hwan

2014-12-01

To investigate the risk and risk factors for newly developed visual impairment in treated patients with normal-tension glaucoma (NTG) followed up on for 10 years. Patients with NTG, who did not have visual impairment at the initial diagnosis and had undergone intraocular pressure (IOP)-lowering treatment for more than 7 years, were included on the basis of a retrospective chart review. Visual impairment was defined as either low vision (0.05 [20/400] ≤ visual acuity (VA) <0.3 [20/60] and/or 10 degrees ≤ central visual field (VF) <20 degrees) or blindness (VA <0.05 [20/400] and/or central VF <10 degrees) by World Health Organization (WHO) criteria. To investigate the risk and risk factors for newly developed visual impairment, Kaplan-Meier survival analysis and generalized linear mixed effects models were utilized. During the 10.8 years mean follow-up period, 20 eyes of 16 patients were diagnosed as visual impairment (12 eyes as low vision, 8 as blindness) among 623 eyes of 411 patients. The cumulative risk of visual impairment in at least one eye was 2.8% at 10 years and 8.7% at 15 years. The risk factors for visual impairment from treated NTG were worse VF mean deviation (MD) at diagnosis and longer follow-up period. The risk of newly developed visual impairment in the treated patients with NTG was relatively low. Worse VF MD at diagnosis and longer follow-up period were associated with development of visual impairment. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

The Prevalence and Causes of Visual Impairment and Blindness Among Older Adults in the City of Lodz, Poland

PubMed Central

Nowak, Michal S.; Smigielski, Janusz

2015-01-01

Abstract To investigate the prevalence and causes of visual impairment and blindness in a sample of Polish older adults. The study was designed in a cross-sectional and observational manner. Data concerning the vision status were assessed in 2214 eyes from 1107 subjects of European Caucasian origin; most of whom live in the city of Lodz, in central Poland. Visual impairment was defined as distance visual acuity <20/40 in the worse-seeing eye. Low vision was defined as best-corrected visual acuity (BCVA) <20/40 but >20/200 in better-seeing eye, and blindness was defined as BCVA ≤20/200 in both eyes (United States criteria). Visual impairment was found in 27.5% subjects in the worse-seeing eye. Multiple regression analysis showed that increasing age (OR 0.98, 95% CI 0.97–0.99) and female gender (OR 1.47, 95% CI 1.11–1.93) were independent risk factors. No association was found between visual impairment and socioeconomic status of subjects. Noncorrectable visual impairment was found in 7.0% of subjects, including 5.2% of subjects with unilateral and 1.8% of subjects with bilateral visual impairment. Low vision and blindness accounted for 1.3% and 0.5%, respectively, and were only associated with older age (OR 1.05, 95% CI 1.02–1.10). Retinal diseases represented the major cause of noncorrectable visual impairment and accounted for more than half of causes of blindness. Provision of appropriate refractive correction improves visual acuity in 75% subjects presenting with visual impairment. Retinal diseases are a major cause of noncorrectable visual impairment and blindness in this older population. PMID:25654398

The prevalence and causes of visual impairment and blindness among older adults in the city of Lodz, Poland.

PubMed

Nowak, Michal S; Smigielski, Janusz

2015-02-01

To investigate the prevalence and causes of visual impairment and blindness in a sample of Polish older adults. The study was designed in a cross-sectional and observational manner. Data concerning the vision status were assessed in 2214 eyes from 1107 subjects of European Caucasian origin; most of whom live in the city of Lodz, in central Poland. Visual impairment was defined as distance visual acuity <20/40 in the worse-seeing eye. Low vision was defined as best-corrected visual acuity (BCVA) <20/40 but >20/200 in better-seeing eye, and blindness was defined as BCVA ≤20/200 in both eyes (United States criteria). Visual impairment was found in 27.5% subjects in the worse-seeing eye. Multiple regression analysis showed that increasing age (OR 0.98, 95% CI 0.97-0.99) and female gender (OR 1.47, 95% CI 1.11-1.93) were independent risk factors. No association was found between visual impairment and socioeconomic status of subjects. Noncorrectable visual impairment was found in 7.0% of subjects, including 5.2% of subjects with unilateral and 1.8% of subjects with bilateral visual impairment. Low vision and blindness accounted for 1.3% and 0.5%, respectively, and were only associated with older age (OR 1.05, 95% CI 1.02-1.10). Retinal diseases represented the major cause of noncorrectable visual impairment and accounted for more than half of causes of blindness. Provision of appropriate refractive correction improves visual acuity in 75% subjects presenting with visual impairment. Retinal diseases are a major cause of noncorrectable visual impairment and blindness in this older population.

Perceptual and associative knowledge in category specific impairment of semantic memory: a study of two cases.

PubMed

Laiacona, M; Barbarotto, R; Capitani, E

1993-12-01

We report two head-injured patients whose knowledge of living things was selectively disrupted. Their semantic knowledge was tested with naming and verbal comprehension tasks and a verbal questionnaire. In all of them there was consistent evidence that knowledge of living things was impaired and that of non-living things was relatively preserved. The living things deficit emerged irrespective of whether the question tapped associative or perceptual knowledge or required visual or non visual information. In all tasks the category effect was still significant after the influence on the performance of the following variables was partialled out: word frequency, concept familiarity, prototypicality, name agreement, image agreement and visual complexity. In the verbal questionnaire dissociations were still significant even after adjustment for the difficulty of questions for normals, that had proven greater for living things. Besides diffuse brain damage, both patients presented with a left posterior temporo-parietal lesion.

Alcohol Use in German Adolescents with Visual Impairments and Sighted Adolescents

ERIC Educational Resources Information Center

Pinquart, Martin; Pfeiffer, Jens P.

2010-01-01

Alcohol use was studied in 158 adolescents with visual impairments and 537 sighted adolescents in Germany. The students with visual impairments reported lower levels of alcohol use and drunkenness, and between-group differences increased across adolescence. The lower alcohol use by students with visual impairments was explained, in part, by the…

Promoting Leisure-Time Physical Activity for Students with Visual Impairments Using Generalization Tactics

ERIC Educational Resources Information Center

Haegele, Justin A.

2015-01-01

Important and favorable health effects of physical activity have been well documented. Unfortunately, school-aged individuals who are visually impaired tend to be less physically active than their peers without visual impairments. Although students with visual impairments learn skills to participate in physical activities during their PE classes,…

Nature Trails for the Visually Impaired.

ERIC Educational Resources Information Center

Schwartz, Jonathan R.

Many interpretive nature trails have been established for the visually impaired in recent years. The objectives of the investigation were to (a) identify what has been done in the past in the way of nature trail design for the visually impaired, (b) compare this with what professional workers for the visually impaired consider important in the…

Public Computer Assisted Learning Facilities for Children with Visual Impairment: Universal Design for Inclusive Learning

ERIC Educational Resources Information Center

Siu, Kin Wai Michael; Lam, Mei Seung

2012-01-01

Although computer assisted learning (CAL) is becoming increasingly popular, people with visual impairment face greater difficulty in accessing computer-assisted learning facilities. This is primarily because most of the current CAL facilities are not visually impaired friendly. People with visual impairment also do not normally have access to…

Assistive Technology Competencies of Teachers of Students with Visual Impairments: A Comparison of Perceptions

ERIC Educational Resources Information Center

Zhou, Li; Smith, Derrick W.; Parker, Amy T.; Griffin-Shirley, Nora

2011-01-01

This study surveyed teachers of students with visual impairments in Texas on their perceptions of a set of assistive technology competencies developed for teachers of students with visual impairments by Smith and colleagues (2009). Differences in opinion between practicing teachers of students with visual impairments and Smith's group of…

The Emancipation of Visually Impaired People in Social Science Research Practice

ERIC Educational Resources Information Center

Duckett, Paul; Pratt, Rebekah

2007-01-01

In 1999 we began research, funded by the "Thomas Clinton Trust", to explore the opinions of visually impaired people on visual impairment research. We found people wanted greater inclusion of visually impaired people in such research and participatory, empowering and emancipatory research was a priority for them. We also found, through reviewing…

Burden, etiology and predictors of visual impairment among children attending Mulago National Referral Hospital eye clinic, Uganda.

PubMed

Kinengyere, Patience; Kizito, Samuel; Kiggundu, John Baptist; Ampaire, Anne; Wabulembo, Geoffrey

2017-09-01

Childhood visual impairment (CVI) has not been given due attention. Knowledge of CVI is important in planning preventive measures. The aim of this study was determine the prevalence, etiology and the factors associated with childhood visual impairment among the children attending the eye clinic in Mulago National Referral Hospital. This was a cross sectional hospital based study among 318 children attending the Mulago Hospital eye clinic between January 2015 to March 2015. Ocular and general history was taken and patient examination done. The data generated was entered by Epidata and analyzed by STATA 12. The prevalence of CVI was 42.14%, 134 patients with 49 patients (15.41%) having moderate visual impairment, 45 patients (14.15%) having severe visual impairment and 40 patients (12.58%) presenting with blindness. Significant predictors included; increasing age, delayed developmental milestones and having abnormal corneal, refractive and fundus findings. There is a high burden of visual impairment among children in Uganda. It is vital to screen all the children presenting to hospital for visual impairment. Majority of the causes of the visual impairment are preventable.

Binding of Visual and Spatial Short-Term Memory in Williams Syndrome and Moderate Learning Disability

ERIC Educational Resources Information Center

Jarrold, Christopher; Phillips, Caroline; Baddeley, Alan D

2007-01-01

A main aim of this study was to test the claim that individuals with Williams syndrome have selectively impaired memory for spatial as opposed to visual information. The performance of 16 individuals with Williams syndrome (six males, 10 females; mean age 18y 7mo [SD 7y 6mo], range 9y 1mo-30y 7mo) on tests of short-term memory for item and…

Selection Difficulty and Interitem Competition Are Independent Factors in Rapid Visual Stream Perception

ERIC Educational Resources Information Center

Kawahara, Jun-ichiro; Enns, James T.

2009-01-01

When observers try to identify successive targets in a visual stream at a rate of 100 ms per item, accuracy for the 2nd target is impaired for intertarget lags of 100-500 ms. Yet, when the same stream is presented more rapidly (e.g., 50 ms per item), this pattern reverses and a 1st-target deficit is obtained. M. C. Potter, A. Staub, and D. H.…

Social Inequality and Visual Impairment in Older People.

PubMed

Whillans, Jennifer; Nazroo, James

2018-03-02

Visual impairment is the leading cause of age-related disability, but the social patterning of loss of vision in older people has received little attention. This study's objective was to assess the association between social position and onset of visual impairment, to empirically evidence health inequalities in later life. Visual impairment was measured in 2 ways: self-reporting fair vision or worse (moderate) and self-reporting poor vision or blindness (severe). Correspondingly, 2 samples were drawn from the English Longitudinal Study on Ageing (ELSA). First, 7,483 respondents who had good vision or better at Wave 1; second, 8,487 respondents who had fair vision or better at Wave 1. Survival techniques were used. Cox proportional hazards models showed wealth and subjective social status (SSS) were significant risk factors associated with the onset of visual impairment. The risk of onset of moderate visual impairment was significantly higher for the lowest and second lowest wealth quintiles, whereas the risk of onset of severe visual impairment was significantly higher for the lowest, second, and even middle wealth quintiles, compared with the highest wealth quintile. Independently, lower SSS was associated with increased risk of onset of visual impairment (both measures), particularly so for those placing themselves on the lowest rungs of the social ladder. The high costs of visual impairment are disproportionately felt by the worst off elderly. Both low wealth and low SSS significantly increase the risk of onset of visual impairment.

Exploring Visual Selective Attention towards Novel Stimuli in Alzheimer's Disease Patients.

PubMed

Chau, Sarah A; Herrmann, Nathan; Eizenman, Moshe; Chung, Jonathan; Lanctôt, Krista L

2015-01-01

Alzheimer's disease (AD) is associated with selective attention impairments, which could contribute to cognitive and functional deficits. Selective attention can be explored through examination of novelty preference. In this study, we quantified novelty preference in AD patients by measuring visual scanning behaviour using an eye tracking paradigm. Mild-to-moderate AD patients and elderly controls viewed slides containing novel and repeated images simultaneously. The outcome measure was time spent on specific images, with novelty preference defined by greater relative fixation time (RFT) on novel versus repeated images. Cognitive status (Standardized Mini-Mental State Examination, SMMSE) and attention (Digit Span, DS) were also measured. AD patients (age 79.2 ± 6.7 years, SMMSE 22.2 ± 4.0, n = 41) and controls (age 76.2 ± 6.4 years, SMMSE 28.1 ± 2.0, n = 24) were similar in age, education and sex. Compared with controls, AD patients had lower RFT on novel than on repeated images (F1,63 = 11.18, p = 0.001). Further, reduced RFT was associated with lower scores on SMMSE (r63 = 0.288, p = 0.020) and DS (r63 = 0.269, p = 0.030). Within individuals, novelty preference was detected in 92.3% of patients and in 100% of controls. These findings suggest that novelty preference, measured by visual scanning behaviour, can differentiate cognitively healthy and impaired people and may offer a nonverbal, less cognitively demanding method of assessing selective attention.

A Nationwide Cross-Sectional Survey of Sleep-Related Problems in Japanese Visually Impaired Patients: Prevalence and Association with Health-Related Quality of Life.

PubMed

Tamura, Norihisa; Sasai-Sakuma, Taeko; Morita, Yuko; Okawa, Masako; Inoue, Shigeru; Inoue, Yuichi

2016-12-15

This questionnaire-based cross-sectional study was conducted (1) to estimate the prevalence of sleep-related problems, and (2) to explore factors associated with lower physical/mental quality of life (QOL), particularly addressing sleep-related problems among Japanese visually impaired people. This nationwide questionnaire-based survey was administered to visually impaired individuals through the Japan Federation of the Blind. Visually impaired individuals without light perception (LP) (n = 311), those with LP (n = 287), and age-matched and gender-matched controls (n = 615) were eligible for this study. Study questionnaires elicited demographic information, and information about visual impairment status, sleep-related problems, and health-related quality of life. Visually impaired individuals with and without LP showed higher prevalence rates of irregular sleep-wake patterns and difficulty maintaining sleep than controls (34.7% and 29.4% vs. 15.8%, 60.1% and 46.7% vs. 26.8%, respectively; p < 0.001). These sleep-related problems were observed more frequently in visually impaired individuals without LP than in those with LP. Non-restorative sleep or excessive daytime sleepiness was associated with lower mental/physical QOL in visually impaired individuals with LP and in control subjects. However, visually impaired individuals without LP showed irregular sleep-wake pattern or difficulty waking up at the desired time, which was associated with lower mental/physical QOL. Sleep-related problems were observed more frequently in visually impaired individuals than in controls. Moreover, the rates of difficulties were higher among subjects without LP. Sleep-related problems, especially circadian rhythm-related ones, can be associated with lower mental/physical QOL in visually impaired individuals without LP. © 2016 American Academy of Sleep Medicine

Spatial attention does not require preattentive grouping.

PubMed

Vecera, S P; Behrmann, M

1997-01-01

Does spatial attention follow a full preattentive analysis of the visual field, or can attention select from ungrouped regions of the visual field? We addressed this question by testing an apperceptive agnosic patient, J. W., in tasks involving both spatial selection and preattentive grouping. Results suggest that J.W. had intact spatial attention: He was faster to detect targets appearing at cued location relative to targets appearing at uncued locations. However, his preattentive processes were severely disrupted. Gestalt grouping and symmetry perception, both thought to involve preattentive processes, were impaired in J. W. Also, he could not use gestalt grouping cues to guide spatial attention. These results suggest that spatial attention is not completely dependent on preattentive grouping processes. We argue that preattentive grouping processes and spatial attention may mutually constrain one another in guiding the attentional selection of visual stimuli but that these 2 processes are isolated from one another.

A Nationwide Cross-Sectional Survey of Sleep-Related Problems in Japanese Visually Impaired Patients: Prevalence and Association with Health-Related Quality of Life

PubMed Central

Tamura, Norihisa; Sasai-Sakuma, Taeko; Morita, Yuko; Okawa, Masako; Inoue, Shigeru; Inoue, Yuichi

2016-01-01

Study Objectives: This questionnaire-based cross-sectional study was conducted (1) to estimate the prevalence of sleep-related problems, and (2) to explore factors associated with lower physical/mental quality of life (QOL), particularly addressing sleep-related problems among Japanese visually impaired people. Methods: This nationwide questionnaire-based survey was administered to visually impaired individuals through the Japan Federation of the Blind. Visually impaired individuals without light perception (LP) (n = 311), those with LP (n = 287), and age-matched and gender-matched controls (n = 615) were eligible for this study. Study questionnaires elicited demographic information, and information about visual impairment status, sleep-related problems, and health-related quality of life. Results: Visually impaired individuals with and without LP showed higher prevalence rates of irregular sleep-wake patterns and difficulty maintaining sleep than controls (34.7% and 29.4% vs. 15.8%, 60.1% and 46.7% vs. 26.8%, respectively; p < 0.001). These sleep-related problems were observed more frequently in visually impaired individuals without LP than in those with LP. Non-restorative sleep or excessive daytime sleepiness was associated with lower mental/physical QOL in visually impaired individuals with LP and in control subjects. However, visually impaired individuals without LP showed irregular sleep-wake pattern or difficulty waking up at the desired time, which was associated with lower mental/physical QOL. Conclusions: Sleep-related problems were observed more frequently in visually impaired individuals than in controls. Moreover, the rates of difficulties were higher among subjects without LP. Sleep-related problems, especially circadian rhythm-related ones, can be associated with lower mental/physical QOL in visually impaired individuals without LP. Citation: Tamura N, Sasai-Sakuma T, Morita Y, Okawa M, Inoue S, Inoue Y. A nationwide cross-sectional survey of sleep-related problems in Japanese visually impaired patients: prevalence and association with health-related quality of life. J Clin Sleep Med 2016;12(12):1659–1667. PMID:27655465

Sleep deprivation impairs object-selective attention: a view from the ventral visual cortex.

PubMed

Lim, Julian; Tan, Jiat Chow; Parimal, Sarayu; Dinges, David F; Chee, Michael W L

2010-02-05

Most prior studies on selective attention in the setting of total sleep deprivation (SD) have focused on behavior or activation within fronto-parietal cognitive control areas. Here, we evaluated the effects of SD on the top-down biasing of activation of ventral visual cortex and on functional connectivity between cognitive control and other brain regions. Twenty-three healthy young adult volunteers underwent fMRI after a normal night of sleep (RW) and after sleep deprivation in a counterbalanced manner while performing a selective attention task. During this task, pictures of houses or faces were randomly interleaved among scrambled images. Across different blocks, volunteers responded to house but not face pictures, face but not house pictures, or passively viewed pictures without responding. The appearance of task-relevant pictures was unpredictable in this paradigm. SD resulted in less accurate detection of target pictures without affecting the mean false alarm rate or response time. In addition to a reduction of fronto-parietal activation, attending to houses strongly modulated parahippocampal place area (PPA) activation during RW, but this attention-driven biasing of PPA activation was abolished following SD. Additionally, SD resulted in a significant decrement in functional connectivity between the PPA and two cognitive control areas, the left intraparietal sulcus and the left inferior frontal lobe. SD impairs selective attention as evidenced by reduced selectivity in PPA activation. Further, reduction in fronto-parietal and ventral visual task-related activation suggests that it also affects sustained attention. Reductions in functional connectivity may be an important additional imaging parameter to consider in characterizing the effects of sleep deprivation on cognition.

Association of Visual Acuity and Cognitive Impairment in Older Individuals: Fujiwara-kyo Eye Study

PubMed Central

Mine, Masashi; Miyata, Kimie; Morikawa, Masayuki; Nishi, Tomo; Okamoto, Nozomi; Kawasaki, Ryo; Yamashita, Hidetoshi; Kurumatani, Norio; Ogata, Nahoko

2016-01-01

Abstract Both visual impairment and cognitive impairment are essential factors that determine the quality of life in the aged population. The aim of this study was to determine if a correlation existed between visual acuity and cognitive impairment in an elderly Japanese population. The Fujiwara-kyo Eye Study was a cross-sectional study of individuals aged ≥68 years who lived in Nara Prefecture of Japan. Participants underwent ophthalmological examinations and cognitive function test. A mild visual impairment was defined as having a best corrected visual acuity (BCVA) >0.2 logarithm of the minimum angle of resolution (logMAR) units in the better eye. Cognitive impairment was defined as having a Mini-Mental State Examination (MMSE) score of ≤23 points. A total to 2818 individuals completed the examinations. The mean age of the participants was 76.3 ± 4.8 years (mean ± standard deviation). The mean BCVA of the better eye was −0.02 ± 0.13 logMAR units and 6.6% subjects were classified as being mildly visually impaired. The mean MMSE score was 27.3 ± 2.3 and 5.7% subjects were classified as being cognitively impaired. The proportion of subjects with cognitive or moderate visual impairment increased with age, and there was a significant correlation between the visual acuity and MMSE score (r = −0.10, p < 0.0001). Subjects with mild visual impairments had 2.4 times higher odds of having cognitive impairment than those without visual impairment (odds ratio 2.4, 95% confidence interval, 1.5–3.8, p < 0.001) after adjusting for age, sex, and length of education. We conclude that it may be important to maintain good visual acuity to reduce the risk of having cognitive impairment. PMID:27610269

Visual defects and commercial motorcycle accidents in south eastern Nigeria.

PubMed

Achigbu, E O; Fiebai, B

2013-01-01

Commercial motorcyclists are a regular part of our highways, especially with the decrease in the number and quality of good roads. This study is aimed at determining the role of vision if any in the increasing number of road traffic accidents (RTA's) among commercial motorcyclists in Enugu metropolis, Nigeria. A cross sectional survey with a multi stage random sampling design was used to select the 615 commercial motorcyclists in Enugu metropolis enrolled in the study. Out of the 615 motorcyclists, seven (1.14% +/- 0.70%) motorcyclists had visual impairment (< 6/18-3/60). Visual field defect was noted in 2.3% +/- 0.98% while 2.6% +/- 0.98% had colour vision defect. The prevalence of road traffic accident (RTA) was 57.7%. Visual impairment was not significantly associated with RTA (P = 0.333) while visual field defect (P = 0.000), and colour vision defect (P = 0.003) were positively associated with RTA. Inexperienced riders had significantly more RTAs than their counterparts (P = 0.000). CONCLUSION; Visual field defect, and colour vision defect were significantly associated with RTA but this finding is in the backdrop of poor training, and inexperience which also significantly affected RTA among the predominantly young riders involved in RTA.

Rapid assessment of avoidable blindness in Bhutan.

PubMed

Lepcha, Nor Tshering; Chettri, Chandra Kumar; Getshen, Kunzang; Rai, Bhim Bahadur; Ramaswamy, Shamanna Bindiganavale; Saibaba, Saravanan; Nirmalan, Praveen Kumar; Demarchis, Emilia Hansson; Tabin, Geoffrey; Morley, Michael; Morley, Katharine

2013-08-01

To conduct a rapid assessment of avoidable blindness survey in Bhutan to obtain estimates of blindness, visual impairment, and cataract surgical coverage, outcomes and barriers among persons ≥50 years old. A total of 82 clusters of 50 people ≥50 years were selected using probability proportionate to size sampling. Eligible participants were selected from households using compact segment sampling, and underwent ophthalmic examination for visual acuity, followed by penlight and direct ophthalmoscopy. Participants with cataract were interviewed regarding surgical outcomes and barriers to surgery. Overall, 4046 of 4100 persons enumerated (98.7%) underwent ophthalmic examination. Adjusting for age and sex, the prevalence of bilaterally blind persons with available correction was 1.5% (95% confidence interval 1.09-1.89). Most blindness (67.1%) and severe visual impairment (74.1%) resulted from cataract, but 22.1% resulted from posterior segment pathology. Cataract surgical coverage for bilaterally blind persons was 72.7%. Almost 90% of patients reported moderate or good satisfaction, despite poor surgical outcomes in 23.6%. The prevalence of blindness in people aged ≥50 years in Bhutan was relatively low when compared with neighboring countries and World Health Organization sub-region estimates. Areas for improvement include community outreach, surgical outcomes, and posterior segment diseases.

An enhanced functional ability questionnaire (faVIQ) to measure the impact of rehabilitation services on the visually impaired

PubMed Central

Wolffsohn, James Stuart; Jackson, Jonathan; Hunt, Olivia Anne; Cottriall, Charles; Lindsay, Jennifer; Gilmour, Richard; Sinclair, Anne; Harper, Robert

2014-01-01

AIM To develop a short, enhanced functional ability Quality of Vision (faVIQ) instrument based on previous questionnaires employing comprehensive modern statistical techniques to ensure the use of an appropriate response scale, items and scoring of the visual related difficulties experienced by patients with visual impairment. METHODS Items in current quality-of-life questionnaires for the visually impaired were refined by a multi-professional group and visually impaired focus groups. The resulting 76 items were completed by 293 visually impaired patients with stable vision on two occasions separated by a month. The faVIQ scores of 75 patients with no ocular pathology were compared to 75 age and gender matched patients with visual impairment. RESULTS Rasch analysis reduced the faVIQ items to 27. Correlation to standard visual metrics was moderate (r=0.32-0.46) and to the NEI-VFQ was 0.48. The faVIQ was able to clearly discriminate between age and gender matched populations with no ocular pathology and visual impairment with an index of 0.983 and 95% sensitivity and 95% specificity using a cut off of 29. CONCLUSION The faVIQ allows sensitive assessment of quality-of-life in the visually impaired and should support studies which evaluate the effectiveness of low vision rehabilitation services. PMID:24634868

An enhanced functional ability questionnaire (faVIQ) to measure the impact of rehabilitation services on the visually impaired.

PubMed

Wolffsohn, James Stuart; Jackson, Jonathan; Hunt, Olivia Anne; Cottriall, Charles; Lindsay, Jennifer; Gilmour, Richard; Sinclair, Anne; Harper, Robert

2014-01-01

To develop a short, enhanced functional ability Quality of Vision (faVIQ) instrument based on previous questionnaires employing comprehensive modern statistical techniques to ensure the use of an appropriate response scale, items and scoring of the visual related difficulties experienced by patients with visual impairment. Items in current quality-of-life questionnaires for the visually impaired were refined by a multi-professional group and visually impaired focus groups. The resulting 76 items were completed by 293 visually impaired patients with stable vision on two occasions separated by a month. The faVIQ scores of 75 patients with no ocular pathology were compared to 75 age and gender matched patients with visual impairment. Rasch analysis reduced the faVIQ items to 27. Correlation to standard visual metrics was moderate (r=0.32-0.46) and to the NEI-VFQ was 0.48. The faVIQ was able to clearly discriminate between age and gender matched populations with no ocular pathology and visual impairment with an index of 0.983 and 95% sensitivity and 95% specificity using a cut off of 29. The faVIQ allows sensitive assessment of quality-of-life in the visually impaired and should support studies which evaluate the effectiveness of low vision rehabilitation services.

Prevalence of Visual Impairment and Refractive Errors in Children of South Sinai, Egypt.

PubMed

Yamamah, Gamal Abdel Naser; Talaat Abdel Alim, Ahmed Ahmed; Mostafa, Yehia Salah El Din; Ahmed, Rania Ahmed Abdel Salam; Mohammed, Asmaa Mahmoud; Mahmoud, Asmaa Mohammed

2015-01-01

To assess the prevalence and causes of visual impairment in children of South Sinai, and to evaluate outcomes of rehabilitation programs. Population-based, cross-sectional analysis of 2070 healthy school children screened for visual impairment from 2009 through 2010 in cities of South Sinai and their surrounding Bedouin settlements. Visual acuity (VA) was tested using Snellen charts followed by cycloplegic autorefractometry for cases with presenting VA ≤ 6/9. Appropriate eyeglasses were prescribed and VA re-evaluated. This study included 1047 boys and 1023 girls, mean age 10.7 ± 3.1 years. Visual impairment (uncorrected VA ≤ 6/9) was detected in 29.4% of children, while 2.0% had moderate-severe visual impairment (uncorrected VA ≤ 6/24). There were statistically significant differences in prevalence of visual impairment between the studied cities (p < 0.05), with the highest prevalence in Abu Redis. Prevalence of visual impairment was significantly higher among girls (p < 0.05) and those with positive consanguinity (p < 0.05). Bedouin children showed significantly lower prevalences of visual impairment. Only age was a reliable predictor of visual impairment (odds ratio 0.94, p < 0.0001). Ophthalmic examination revealed other disorders, e.g. dry eye (4.74%), squint (2.37%), exophthalmos (1.58%) and ptosis (0.79%). VA significantly improved in children who received spectacles (p < 0.001). A total of 29.4% of South Sinai children had some form of visual impairment, 90.32% of which comprised refractive errors (mainly astigmatism) which were significantly corrected with eyeglasses. VA screening and correction of refractive errors are of the utmost importance for ensuring better visual outcomes and improved school performance.

Quality of life in patients with visual impairment in Ibadan: a clinical study in primary care.

PubMed

Adigun, Kehinde; Oluleye, Tunji S; Ladipo, Modupe Ma; Olowookere, Samuel Anu

2014-01-01

Visual function is important for optimal orientation in functional and social life, and has an effect on physical and emotional well-being. Visual impairment, therefore, leads to restrictions in all aspects of daily living and is related to quality of life. The aim of this study was to provide information on the causes of visual impairment in patients presenting to their family physician, the spectrum of impairment, and its impact on quality of life for these patients. This descriptive cross-sectional study of 375 adult patients with ocular symptoms was performed in the general outpatient department of the University College Hospital, Ibadan, from July to September, 2009. After checking their presenting visual acuity, the patients were interviewed using the Vision-Related Quality of Life questionnaire to determine the impact of visual impairment on their quality of life. Ophthalmic examinations were performed to determine the causes of visual impairment. The results were analyzed using proportions and percentages. The main causes of visual impairment were cataracts (58.7%), refractive error (19.4%), and glaucoma (2.9%). Visual impairment was found to be associated with advancing age, low education, and unemployment (P<0.001). Most patients (85.1%) were found to have good quality of life overall. Quality of life was found to be poor in the domains of visual function (64.2%) and social interaction (50.9%). Quality of life was found to be related to the degree of visual impairment, ie, blind patients reported poor quality of life (41.4%) when compared with those having low vision (8.6%) or near normal vision (2.4%, P<0.001). This study identified poor quality of life in patients with a higher degree of visual impairment. Family physicians need to identify these visually impaired patients early and make timely referrals.

Does Visual Impairment Affect Social Ties in Late Life? Findings of a Multicenter Prospective Cohort Study in Germany.

PubMed

Hajek, A; Brettschneider, C; Lühmann, D; Eisele, M; Mamone, S; Wiese, B; Weyerer, S; Werle, J; Pentzek, M; Fuchs, A; Stein, J; Luck, T; Bickel, H; Weeg, D; Heser, K; Jessen, F; Maier, W; Scherer, M; Riedel-Heller, S G; König, H-H

2017-01-01

To investigate how visual impairment affects social ties in late life longitudinally. Population-based prospective cohort study. Individuals in old age were recruited via general practitioners' offices (at six study centers) in Germany. They were interviewed every 18 months. Individuals aged 75 years and above at baseline. Follow-up wave 2 (36 months after baseline, n=2,443) and wave 4 (72 months after baseline, n=1,618) were used for the analyses presented here. Social ties were assessed using the 14-item form of the questionnaire for social support (F-SozU K-14). Visual impairment was self-rated on a three level Likert scale (no impairment, mild visual impairment, or severe/profound visual impairment). Adjusting for sociodemographic factors, hearing impairment and comorbidity, fixed effects regressions revealed that the onset of mild visual impairment decreased the social support score, in particular the emotional support score. Additionally, the onset of mild hearing impairment decreased the social support score in men. Moreover, increasing age decreased the social support score in the total sample and in both sexes. Loss of spouse and increasing comorbidity did not affect the social support score. Our results highlight the importance of visual impairment for social ties in late life. Consequently, appropriate strategies in order to delay visual impairment might help to maintain social ties in old age.

Amblyopia: neural basis and therapeutic approaches.

PubMed

Bretas, Caio César Peixoto; Soriano, Renato Nery

2016-01-01

Abnormalities in visual processing caused by visual deprivation or abnormal binocular interaction may induce amblyopia, which is characterized by reduced visual acuity. Occlusion therapy, the conventional treatment, requires special attention as occlusion of the fellow normal eye may reduce its visual acuity and impair binocular vision. Besides recovering visual acuity, some researchers have recommended restoration of stereoacuity and motor fusion and reverse suppression in order to prevent diplopia. Recent studies have documented that the amblyopic visual cortex has a normal complement of cells but reduced spatial resolution and a disordered topographical map. Changes occurring in the late sensitive period selectively impact the parvocellular pathway. Distinct morphophysiologic and psychophysical deficits may demand individualization of therapy, which might provide greater and longer-lasting residual plasticity in some children.

Vision In Stroke cohort: Profile overview of visual impairment.

PubMed

Rowe, Fiona J

2017-11-01

To profile the full range of visual disorders from a large prospective observation study of stroke survivors referred by stroke multidisciplinary teams to orthoptic services with suspected visual problems. Multicenter prospective study undertaken in 20 acute Trust hospitals. Standardized screening/referral forms and investigation forms documented data on referral signs and symptoms plus type and extent of visual impairment. Of 1,345 patients referred with suspected visual impairment, 915 were recruited (59% men; mean age at stroke onset 69 years [SD 14]). Initial visual assessment was at median 22 days post stroke onset. Eight percent had normal visual assessment. Of 92% with confirmed visual impairment, 24% had reduced central visual acuity <0.3 logMAR and 13.5% <0.5 logMAR. Acquired strabismus was noted in 16% and acquired ocular motility disorders in 68%. Peripheral visual field loss was present in 52%, most commonly homonymous hemianopia. Fifteen percent had visual inattention and 4.6% had other visual perceptual disorders. Overall 84% were visually symptomatic with visual field loss the most common complaint followed by blurred vision, reading difficulty, and diplopia. Treatment options were provided to all with confirmed visual impairment. Targeted advice was most commonly provided along with refraction, prisms, and occlusion. There are a wide range of visual disorders that occur following stroke and, frequently, with visual symptoms. There are equally a wide variety of treatment options available for these individuals. All stroke survivors require screening for visual impairment and warrant referral for specialist assessment and targeted treatment specific to the type of visual impairment.

Blind Spots: The Communicative Performance of Visual Impairment in Relationships and Social Interaction

ERIC Educational Resources Information Center

Frame, Melissa J.

2004-01-01

The purpose of this book is to understand the experiences of persons who are visually impaired, including those who are invisibly visually impaired. Through the use of a survey questionnaire and interviews and employing a cross-sectional survey design, the study examines the experiences of a large number of visually impaired respondents. The…

Gross Motor Skills and Sports Participation of Children with Visual Impairments

ERIC Educational Resources Information Center

Houwen, Suzanne; Visscher, Chris; Hartman, Esther; Lemmink, Koen A. P. M.

2007-01-01

Gross motor skill performance of children with visual impairments and its association with the degree of visual impairment and sports participation was examined. Twenty children with visual impairments (M age = 9.2 years, SD = 1.5) and 100 sighted children (M age = 9.1 years, SD = 1.5) from mainstream schools participated. The results showed that…

The Reliability of the CVI Range: A Functional Vision Assessment for Children with Cortical Visual Impairment

ERIC Educational Resources Information Center

Newcomb, Sandra

2010-01-01

Children who are identified as visually impaired frequently have a functional vision assessment as one way to determine how their visual impairment affects their educational performance. The CVI Range is a functional vision assessment for children with cortical visual impairment. The purpose of the study presented here was to examine the…

Are Male Judokas with Visual Impairments Training Properly? Findings from an Observational Study

ERIC Educational Resources Information Center

Gutierrez-Santiago, Alfonso; Cancela, Jose M.; Zubiaur, Marta; Ayan, Carlos

2012-01-01

Introduction: One aim of the study was to describe the temporal structure of judo combat among male judokas with visual impairments. Another aim was to determine the possible differences between the judokas with visual impairments and sighted male judokas to determine whether judokas with visual impairments need specific training to achieve their…

38 CFR 4.75 - General considerations for evaluating visual impairment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... refraction), visual field, and muscle function. (b) Examination for visual impairment. The examination must.... Examinations of visual fields or muscle function will be conducted only when there is a medical indication of disease or injury that may be associated with visual field defect or impaired muscle function. Unless...

38 CFR 4.75 - General considerations for evaluating visual impairment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... refraction), visual field, and muscle function. (b) Examination for visual impairment. The examination must.... Examinations of visual fields or muscle function will be conducted only when there is a medical indication of disease or injury that may be associated with visual field defect or impaired muscle function. Unless...

38 CFR 4.75 - General considerations for evaluating visual impairment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... refraction), visual field, and muscle function. (b) Examination for visual impairment. The examination must.... Examinations of visual fields or muscle function will be conducted only when there is a medical indication of disease or injury that may be associated with visual field defect or impaired muscle function. Unless...

Inferential functioning in visually impaired children.

PubMed

Puche-Navarro, Rebeca; Millán, Rafael

2007-01-01

The current study explores the inferential abilities of visually impaired children in a task presented in two formats, manipulative and verbal. The results showed that in the group of visually impaired children, just as with children with normal sight, there was a wide range of inference types. It was found that the visually impaired children perform slightly better in the use of inductive and relational inferences in the verbal format, while in the manipulative format children with normal sight perform better. These results suggest that in inferential functioning of young children, and especially visually impaired children, the format of the task influences performance more than the child's visual ability.

Emotional and Behavioural Problems in Children with Visual Impairment, Intellectual and Multiple Disabilities

ERIC Educational Resources Information Center

Alimovic, S.

2013-01-01

Background: Children with multiple impairments have more complex developmental problems than children with a single impairment. Method: We compared children, aged 4 to 11 years, with intellectual disability (ID) and visual impairment to children with single ID, single visual impairment and typical development on "Child Behavior Check…

The visual attention span deficit in dyslexia is visual and not verbal.

PubMed

Lobier, Muriel; Zoubrinetzky, Rachel; Valdois, Sylviane

2012-06-01

The visual attention (VA) span deficit hypothesis of dyslexia posits that letter string deficits are a consequence of impaired visual processing. Alternatively, some have interpreted this deficit as resulting from a visual-to-phonology code mapping impairment. This study aims to disambiguate between the two interpretations by investigating performance in a non-verbal character string visual categorization task with verbal and non-verbal stimuli. Results show that VA span ability predicts performance for the non-verbal visual processing task in normal reading children. Furthermore, VA span impaired dyslexic children are also impaired for the categorization task independently of stimuli type. This supports the hypothesis that the underlying impairment responsible for the VA span deficit is visual, not verbal. Copyright © 2011 Elsevier Srl. All rights reserved.

Visuospatial selective attention in chickens.

PubMed

Sridharan, Devarajan; Ramamurthy, Deepa L; Schwarz, Jason S; Knudsen, Eric I

2014-05-13

Voluntary control of attention promotes intelligent, adaptive behaviors by enabling the selective processing of information that is most relevant for making decisions. Despite extensive research on attention in primates, the capacity for selective attention in nonprimate species has never been quantified. Here we demonstrate selective attention in chickens by applying protocols that have been used to characterize visual spatial attention in primates. Chickens were trained to localize and report the vertical position of a target in the presence of task-relevant distracters. A spatial cue, the location of which varied across individual trials, indicated the horizontal, but not vertical, position of the upcoming target. Spatial cueing improved localization performance: accuracy (d') increased and reaction times decreased in a space-specific manner. Distracters severely impaired perceptual performance, and this impairment was greatly reduced by spatial cueing. Signal detection analysis with an "indecision" model demonstrated that spatial cueing significantly increased choice certainty in localizing targets. By contrast, error-aversion certainty (certainty of not making an error) remained essentially constant across cueing protocols, target contrasts, and individuals. The results show that chickens shift spatial attention rapidly and dynamically, following principles of stimulus selection that closely parallel those documented in primates. The findings suggest that the mechanisms that control attention have been conserved through evolution, and establish chickens--a highly visual species that is easily trained and amenable to cutting-edge experimental technologies--as an attractive model for linking behavior to neural mechanisms of selective attention.

Disentangling How the Brain is “Wired” in Cortical/Cerebral Visual Impairment (CVI)

PubMed Central

Merabet, Lotfi B.; Mayer, D. Luisa; Bauer, Corinna M.; Wright, Darick; Kran, Barry S.

2017-01-01

Cortical/cerebral visual impairment (CVI) results from perinatal injury to visual processing structures and pathways of the brain and is the most common cause of severe visual impairment/blindness in children in developed countries. Children with CVI display a wide range of visual deficits including decreased visual acuity, impaired visual field function, as well as impairments in higher order visual processing and attention. Together, these visual impairments can dramatically impact upon a child’s development and well-being. Given the complex neurological underpinnings of this condition, CVI is often undiagnosed by eye care practitioners. Furthermore, the neurophysiological basis of CVI in relation to observed visual processing deficits remains poorly understood. Here, we present some of the challenges associated with the clinical assessment and management of individuals with CVI. We discuss how advances in brain imaging are likely to help uncover the underlying neurophysiology of this condition. In particular, we demonstrate how structural and functional neuroimaging approaches can help gain insight into abnormalities of white matter connectivity and cortical activation patterns respectively. Establishing a connection between how changes within the brain relate to visual impairments in CVI will be important for developing effective rehabilitative and education strategies for individuals living with this condition. PMID:28941531

Disentangling How the Brain is "Wired" in Cortical (Cerebral) Visual Impairment.

PubMed

Merabet, Lotfi B; Mayer, D Luisa; Bauer, Corinna M; Wright, Darick; Kran, Barry S

2017-05-01

Cortical (cerebral) visual impairment (CVI) results from perinatal injury to visual processing structures and pathways of the brain and is the most common cause of severe visual impairment or blindness in children in developed countries. Children with CVI display a wide range of visual deficits including decreased visual acuity, impaired visual field function, as well as impairments in higher-order visual processing and attention. Together, these visual impairments can dramatically influence a child's development and well-being. Given the complex neurologic underpinnings of this condition, CVI is often undiagnosed by eye care practitioners. Furthermore, the neurophysiological basis of CVI in relation to observed visual processing deficits remains poorly understood. Here, we present some of the challenges associated with the clinical assessment and management of individuals with CVI. We discuss how advances in brain imaging are likely to help uncover the underlying neurophysiology of this condition. In particular, we demonstrate how structural and functional neuroimaging approaches can help gain insight into abnormalities of white matter connectivity and cortical activation patterns, respectively. Establishing a connection between how changes within the brain relate to visual impairments in CVI will be important for developing effective rehabilitative and education strategies for individuals living with this condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Frequency of Behçet's disease among a group of visually impaired adults.

PubMed

Uyaroglu, Oguz Abdullah; Seyhoglu, Emrah; Erden, Abdulsamet; Vahabov, Cevanşir; Babaoglu, Hakan; Armagan, Berkan; Sari, Alper; Kilic, Levent; Tatar, Olcay; Bilgen, Sule Apras; Karadag, Omer; Kalyoncu, Umut

2018-03-09

Behçet's disease (BD) is one of the reasons of acquired visual impairment among young adults. Ocular involvement is a significant cause of disability in BD. The objective of this study is to assess the prevalence of BD among a group of adults who has visual impairment. Ankara Metropolitan Municipality Education and Technology Center is one of the official institutions which records and follows the demographic data of visually impaired people in Turkey. In November 2014, there were 675 visually impaired people recorded at this center. Medical history was taken from 294 adults by phone in November and December of 2014. Participants were asked if the visual impairment had been either acquired or congenital. If the patients had BD or suspicious BD, they were recalled for detailed investigation which would be carried out by an internist, a rheumatologist and an ophthalmologist. Two hundred thirteen of 294 (72.4%) visually impaired adults were male. One hundred nine of 294 (37.1%) had acquired visual impairment. Six (5.5%) of those 109 patients had BD. Overall prevalence of BD among study group was 2.04%.The median age of people with BD was 35 years. The median age at BD diagnosis was 16.5 years and the median duration from diagnosis to visual loss was 2.5 years. BD is still one of the causes of acquired visual impairment in Turkey. In this study, BD prevalence among a visually impaired adult group was 2.04%. BD accounted for 5.5% among adults who had acquired visual impairment. In a study of 1965, BD prevalence among people with acquired blindness was 12%. However, this study was conducted at pre-immunosuppressive period. Our prevalence is obviously lower than those studies. Extended population-based studies are needed for population estimations.

Discrimination of tenants with a visual impairment on the housing market: Empirical evidence from correspondence tests.

PubMed

Verhaeghe, Pieter-Paul; Van der Bracht, Koen; Van de Putte, Bart

2016-04-01

According to the social model of disability, physical 'impairments' become disabilities through exclusion in social relations. An obvious form of social exclusion might be discrimination, for instance on the rental housing market. Although discrimination has detrimental health effects, very few studies have examined discrimination of people with a visual impairment. We aim to study (1) the extent of discrimination of individuals with a visual impairment on the rental housing market and (2) differences in rates of discrimination between landowners and real estate agents. We conducted correspondence tests among 268 properties on the Belgian rental housing market. Using matched tests, we compared reactions by realtors and landowners to tenants with and tenants without a visual impairment. The results show that individuals with a visual impairment are substantially discriminated against in the rental housing market: at least one in three lessors discriminate against individuals with a visual impairment. We further discern differences in the propensity toward discrimination according to the type of lessor. Private landlords are at least twice as likely to discriminate against tenants with a visual impairment than real estate agents. At the same time, realtors still discriminate against one in five tenants with a visual impairment. This study shows the substantial discrimination against visually people with an impairment. Given the important consequences discrimination might have for physical and mental health, further research into this topic is needed. Copyright © 2016 Elsevier Inc. All rights reserved.

Visual Impairment in White, Chinese, Black, and Hispanic Participants from the Multi-Ethnic Study of Atherosclerosis Cohort.

PubMed

Fisher, Diana E; Shrager, Sandi; Shea, Steven J; Burke, Gregory L; Klein, Ronald; Wong, Tien Y; Klein, Barbara E; Cotch, Mary Frances

2015-01-01

To describe the prevalence of visual impairment and examine its association with demographic, socioeconomic, and health characteristics in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Visual acuity data were obtained from 6134 participants, aged 46-87 years at time of examination between 2002 and 2004 (mean age 64 years, 47.6% male), from six communities in the United States. Visual impairment was defined as presenting visual acuity 20/50 or worse in the better-seeing eye. Risk factors were included in multivariable logistic regression models to determine their impact on visual impairment for men and women in each racial/ethnic group. Among all participants, 6.6% (n = 421) had visual impairment, including 5.6% of men (n = 178) and 7.5% of women (n = 243). Prevalence of impairment ranged from 4.2% (n = 52) and 6.0% (n = 77) in white men and women, respectively, to 7.6% (n = 37) and 11.6% (n = 44) in Chinese men and women, respectively. Older age was significantly associated with visual impairment in both men and women, particularly in those with lower socioeconomic status, but the effects of increasing age were more pronounced in men. Two-thirds of participants already wore distance correction, and not unexpectedly, a lower prevalence of visual impairment was seen in this group; however, 2.4% of men and 3.5% of women with current distance correction had correctable visual impairment, most notably among seniors. Even in the U.S. where prevalence of refractive correction is high, both visual impairment and uncorrected refractive error represent current public health challenges.

Visual Impairment in White, Chinese, Black and Hispanic Participants from the Multi-Ethnic Study of Atherosclerosis Cohort

PubMed Central

Fisher, Diana E.; Shrager, Sandi; Shea, Steven J.; Burke, Gregory L.; Klein, Ronald; Wong, Tien Y.; Klein, Barbara E; Cotch, Mary Frances

2016-01-01

Purpose To describe the prevalence of visual impairment and examine its association with demographic, socioeconomic, and health characteristics in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Methods Visual acuity data was obtained from 6134 participants, aged 46 to 87 years old at time of examination between 2002 and 2004 (mean age 64 years, 47.6% male), from six communities in the United States (U.S.). Visual impairment was defined as a presenting visual acuity of 20/50 or worse in the better-seeing eye. Risk factors were included in multivariable logistic regression models to determine their impact on visual impairment for men and women in each racial/ethnic group. Results Among all participants, 6.6% (N=421) had visual impairment, including 5.6% (N=178) of men and 7.5% (N=243) of women. Prevalence of impairment ranged from 4.2% (N=52) and 6.0% (N=77) in White men and women, respectively, to 7.6% (N=37) and 11.6% (N=44) in Chinese men and women, respectively. Older age was significantly associated with visual impairment in both men and women, particularly in those with lower socioeconomic status, but the effects of increasing age were more pronounced in men. Two-thirds of participants already wore distance correction and not unexpectedly, lower prevalence of visual impairment was seen in this group; however, 2.4% of men and 3.5% of women with current distance correction had correctable visual impairment, most notably among seniors. Conclusion Even in the United States where prevalence of refractive correction is high, both visual impairment and uncorrected refractive error represent current public health challenges. PMID:26395659

Distance- and near-visual impairment in rural Chinese adults in Kailu, Inner Mongolia.

PubMed

Cheng, Fang; Shan, Li; Song, Wulian; Fan, Pan; Yuan, Huiping

2016-06-01

To investigate the prevalence and causes of distance-visual impairment and near-vision impairment in a rural Chinese population in Inner Mongolia. A population-based, cross-sectional study design was used to identify visual impairment in the Chinese aged 40 years and older living in Kailu County, Inner Mongolia. Low vision, blindness and near-visual impairment (NVI) were defined according to World Health Organization (WHO) criteria. The overall prevalence of blindness and visual impairment based on the presenting visual acuity (VA) was 2.2% (95% CI: 1.8-2.6) and 9.8% (95% CI: 8.9-10.6), respectively, and was adjusted to 0.9% (95% CI: 0.6-1.2) and 4.7% (95% CI: 4.1-5.3) using best-corrected visual acuity (BCVA), respectively. Taking the presenting VA into consideration, the leading cause of visual impairment and blindness was cataract (40.3%, 40.9%), followed by uncorrected refractive error (26.6%, 28.2%). According to the BCVA, the main cause of visual impairment and blindness was cataract (48.3%, 41.3%) followed by glaucoma (19.0%, 23.9%). Among the examined subjects, 80.3% had NVI, and 51.7% had presbyopia. Major barriers reported by NVI persons without near correction were lack of money to purchase prescription glasses and poor quality of the available ones (43.2%). Visual impairment is a serious public health problem, and the main causes leading to visual impairment are treatable and preventable in the rural Chinese population in Inner Mongolia. Presbyopia, together with the low rate of spectacles and lack of appropriate refractive and presbyopia spectacles, is highly prevalent in rural China. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Evaluating the Visually Impaired: Neuropsychological Techniques.

ERIC Educational Resources Information Center

Price, J. R.; And Others

1987-01-01

Assessment of nonvisual neuropsychological impairments in visually impaired persons can be achieved through modification of existing intelligence, memory, sensory-motor, personality, language, and achievement tests so that they do not require vision or penalize visually impaired persons. The Halstead-Reitan and Luria-Nebraska neuropsychological…

Exploring What’s Missing: What Do Target Absent Trials Reveal About Autism Search Superiority?

PubMed Central

Keehn, Brandon; Joseph, Robert M.

2016-01-01

We used eye-tracking to investigate the roles of enhanced discrimination and peripheral selection in superior visual search in autism spectrum disorder (ASD). Children with ASD were faster at visual search than their typically developing peers. However, group differences in performance and eye-movements did not vary with the level of difficulty of discrimination or selection. Rather, consistent with prior ASD research, group differences were mainly the effect of faster performance on target-absent trials. Eye-tracking revealed a lack of left-visual-field search asymmetry in ASD, which may confer an additional advantage when the target is absent. Lastly, ASD symptomatology was positively associated with search superiority, the mechanisms of which may shed light on the atypical brain organization that underlies social-communicative impairment in ASD. PMID:26762114

The Ways of the Hand: A Study of Hand Function among Blind, Visually Impaired and Visually Impaired Multi-Handicapped Children and Adolescents.

ERIC Educational Resources Information Center

Rogow, Sally M.

1987-01-01

The manual development of 148 blind, visually impaired, and visually impaired multi-handicapped students, aged 3-19, was studied. Results indicated a significant relationship between object manipulation and speech, and an inverse relationship between object manipulation and stereotypic hand mannerisms. Optimal development of manual functions and…

Survey Results for Training and Resource Needs Cited by Early Intervention Professionals in the Field of Visual Impairment

ERIC Educational Resources Information Center

Ely, Mindy S.; Ostrosky, Michaelene M.

2017-01-01

Introduction: Professionals working with infants and toddlers with visual impairments (that is, those who are blind or have low vision) were surveyed regarding their preservice training and their awareness and use of 29 resources related to young children who are visually impaired. Methods: Early intervention visual impairment professionals (n =…

Improvement of Fine Motor Skills in Children with Visual Impairment: An Explorative Study

ERIC Educational Resources Information Center

Reimer, A. M.; Cox, R. F. A.; Nijhuis-Van der Sanden, M. W. G.; Boonstra, F. N.

2011-01-01

In this study we analysed the potential spin-off of magnifier training on the fine-motor skills of visually impaired children. The fine-motor skills of 4- and 5-year-old visually impaired children were assessed using the manual skills test for children (6-12 years) with a visual impairment (ManuVis) and movement assessment for children (Movement…

Sociodemographic, lifestyle, and medical risk factors for visual impairment in an urban asian population: the singapore malay eye study.

PubMed

Chong, Elaine W; Lamoureux, Ecosse L; Jenkins, Mark A; Aung, Tin; Saw, Seang-Mei; Wong, Tien Y

2009-12-01

To describe the associations between sociodemographic, lifestyle, and medical risk factors and visual impairment in a Southeast Asian population. Population-based cross-sectional study of 3280 (78.7% response rate) Malay Singaporeans aged 40 to 80 years. Participants underwent a standardized interview, in which detailed sociodemographic histories were obtained, and clinical assessments for presenting and best-corrected visual acuity. Visual impairment (logMAR > 0.30) was classified as unilateral (1 eye impaired) or bilateral (both eyes impaired). Analyses used multivariate-adjusted multinomial logistic regression. Older age and lack of formal education was associated with increased odds of both unilateral and bilateral visual impairment based on presenting and best-corrected visual acuity. The odds doubled for each decade older, and lower education increased the odds 1.59- to 2.83-fold. Bilateral visual impairment was associated with being unemployed (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.30-2.60), widowed status (OR, 1.51; 95% CI, 1.13-2.01), and higher systolic blood pressure (OR, 1.96; 95% CI, 1.44-2.66). Diabetes was associated with unilateral (OR, 1.47; 95% CI, 1.10-1.95) and bilateral (OR, 1.69; 95% CI, 1.23-2.32) visual impairment using best-corrected visual acuity. Older age, lower education, unemployment, being widowed, diabetes, and hypertension were independently associated with bilateral visual impairment. Public health interventions should be targeted to these at-risk populations.

Global data on visual impairment in the year 2002.

PubMed Central

Resnikoff, Serge; Pascolini, Donatella; Etya'ale, Daniel; Kocur, Ivo; Pararajasegaram, Ramachandra; Pokharel, Gopal P.; Mariotti, Silvio P.

2004-01-01

This paper presents estimates of the prevalence of visual impairment and its causes in 2002, based on the best available evidence derived from recent studies. Estimates were determined from data on low vision and blindness as defined in the International statistical classification of diseases, injuries and causes of death, 10th revision. The number of people with visual impairment worldwide in 2002 was in excess of 161 million, of whom about 37 million were blind. The burden of visual impairment is not distributed uniformly throughout the world: the least developed regions carry the largest share. Visual impairment is also unequally distributed across age groups, being largely confined to adults 50 years of age and older. A distribution imbalance is also found with regard to gender throughout the world: females have a significantly higher risk of having visual impairment than males. Notwithstanding the progress in surgical intervention that has been made in many countries over the last few decades, cataract remains the leading cause of visual impairment in all regions of the world, except in the most developed countries. Other major causes of visual impairment are, in order of importance, glaucoma, age-related macular degeneration, diabetic retinopathy and trachoma. PMID:15640920

Global data on visual impairment in the year 2002.

PubMed

Resnikoff, Serge; Pascolini, Donatella; Etya'ale, Daniel; Kocur, Ivo; Pararajasegaram, Ramachandra; Pokharel, Gopal P; Mariotti, Silvio P

2004-11-01

This paper presents estimates of the prevalence of visual impairment and its causes in 2002, based on the best available evidence derived from recent studies. Estimates were determined from data on low vision and blindness as defined in the International statistical classification of diseases, injuries and causes of death, 10th revision. The number of people with visual impairment worldwide in 2002 was in excess of 161 million, of whom about 37 million were blind. The burden of visual impairment is not distributed uniformly throughout the world: the least developed regions carry the largest share. Visual impairment is also unequally distributed across age groups, being largely confined to adults 50 years of age and older. A distribution imbalance is also found with regard to gender throughout the world: females have a significantly higher risk of having visual impairment than males. Notwithstanding the progress in surgical intervention that has been made in many countries over the last few decades, cataract remains the leading cause of visual impairment in all regions of the world, except in the most developed countries. Other major causes of visual impairment are, in order of importance, glaucoma, age-related macular degeneration, diabetic retinopathy and trachoma.

Visual Fast Mapping in School-Aged Children with Specific Language Impairment

ERIC Educational Resources Information Center

Alt, Mary

2013-01-01

Purpose: To determine whether children with specific language impairment (SLI) demonstrate impaired visual fast mapping skills compared with unimpaired peers and to test components of visual working memory that may contribute to a visual working memory deficit. Methods: Fifty children (25 SLI) played 2 computer-based visual fast mapping games…

Prevalence, Causes and Social Factors of Visual Impairment among Chinese Adults: Based on a National Survey.

PubMed

Guo, Chao; Wang, Zhenjie; He, Ping; Chen, Gong; Zheng, Xiaoying

2017-09-08

Visual impairment has become a global challenge, especially for developing countries. This study aims to estimate the prevalence, causes and social factors of visual impairment among Chinese adults. Data were from a nationally representative population-based cross-sectional study. The study population were 1,909,199 non-institutionalized adults aged 18 years and older in mainland China. In the survey, low vision and blindness were checked by ophthalmologists according to the WHO best-corrected visual acuity (BCVA) criteria. Population weighted numbers and prevalence of low vision and blindness with 95% confidence intervals (CIs) were estimated where appropriate. Multivariable logistic regression analysis was used to identify the social factors of visual impairment. The weighted prevalence of visual impairment was 17.17 (95% CI, 16.84-17.50) per 1000 Chinese adults aged 18 years and older. Cataract (57.35%), disorders of choroid and retina (9.80%), and disorders of cornea (6.49%) contributed more than 70 percent to the visual impairment in Chinese adults. Older age groups, young or middle-aged male adults, female elders, illiterate, rural dwellers, non-eastern residents, singles, unemployment, and from family with lower income were associated with visual impairment. More efforts are warranted to enhance treatment and rehabilitation among people with eye disorders to prevent visual impairment.

Prevalence, Causes and Social Factors of Visual Impairment among Chinese Adults: Based on a National Survey

PubMed Central

Wang, Zhenjie; He, Ping; Chen, Gong; Zheng, Xiaoying

2017-01-01

Visual impairment has become a global challenge, especially for developing countries. This study aims to estimate the prevalence, causes and social factors of visual impairment among Chinese adults. Data were from a nationally representative population-based cross-sectional study. The study population were 1,909,199 non-institutionalized adults aged 18 years and older in mainland China. In the survey, low vision and blindness were checked by ophthalmologists according to the WHO best-corrected visual acuity (BCVA) criteria. Population weighted numbers and prevalence of low vision and blindness with 95% confidence intervals (CIs) were estimated where appropriate. Multivariable logistic regression analysis was used to identify the social factors of visual impairment. The weighted prevalence of visual impairment was 17.17 (95% CI, 16.84–17.50) per 1000 Chinese adults aged 18 years and older. Cataract (57.35%), disorders of choroid and retina (9.80%), and disorders of cornea (6.49%) contributed more than 70 percent to the visual impairment in Chinese adults. Older age groups, young or middle-aged male adults, female elders, illiterate, rural dwellers, non-eastern residents, singles, unemployment, and from family with lower income were associated with visual impairment. More efforts are warranted to enhance treatment and rehabilitation among people with eye disorders to prevent visual impairment. PMID:28885571

Viewing behavior and related clinical characteristics in a population of children with visual impairments in the Netherlands.

PubMed

Kooiker, M J G; Pel, J J M; van der Steen, J

2014-06-01

Children with visual impairments are very heterogeneous in terms of the extent of visual and developmental etiology. The aim of the present study was to investigate a possible correlation between prevalence of clinical risk factors of visual processing impairments and characteristics of viewing behavior. We tested 149 children with visual information processing impairments (90 boys, 59 girls; mean age (SD)=7.3 (3.3)) and 127 children without visual impairments (63 boys and 64 girls, mean age (SD)=7.9 (2.8)). Visual processing impairments were classified based on the time it took to complete orienting responses to various visual stimuli (form, contrast, motion detection, motion coherence, color and a cartoon). Within the risk group, children were divided into a fast, medium or slow group based on the response times to a highly salient stimulus. The relationship between group specific response times and clinical risk factors was assessed. The fast responding children in the risk group were significantly slower than children in the control group. Within the risk group, the prevalence of cerebral visual impairment, brain damage and intellectual disabilities was significantly higher in slow responding children compared to faster responding children. The presence of nystagmus, perceptual dysfunctions, mean visual acuity and mean age did not significantly differ between the subgroups. Orienting responses are related to risk factors for visual processing impairments known to be prevalent in visual rehabilitation practice. The proposed method may contribute to assessing the effectiveness of visual information processing in children. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ethnic variation in the prevalence of visual impairment in people attending diabetic retinopathy screening in the United Kingdom (DRIVE UK).

PubMed

Sivaprasad, Sobha; Gupta, Bhaskar; Gulliford, Martin C; Dodhia, Hiten; Mann, Samantha; Nagi, Dinesh; Evans, Jennifer

2012-01-01

To provide estimates of visual impairment in people with diabetes attending screening in a multi-ethnic population in England (United Kingdom). The Diabetic Retinopathy In Various Ethnic groups in UK (DRIVE UK) Study is a cross-sectional study on the ethnic variations of the prevalence of DR and visual impairment in two multi-racial cohorts in the UK. People on the diabetes register in West Yorkshire and South East London who were screened, treated or monitored between April 2008 to July 2009 (London) or August 2009 (West Yorkshire) were included in the study. Data on age, gender, ethnic group, visual acuity and diabetic retinopathy were collected. Ethnic group was defined according to the 2011 census classification. The two main ethnic minority groups represented here are Blacks ("Black/African/Caribbean/Black British") and South Asians ("Asians originating from the Indian subcontinent"). We examined the prevalence of visual impairment in the better eye using three cut-off points (a) loss of vision sufficient for driving (approximately <6/9) (b) visual impairment (<6/12) and (c) severe visual impairment (<6/60), standardising the prevalence of visual impairment in the minority ethnic groups to the age-structure of the white population. Data on visual acuity and were available on 50,331 individuals 3.4% of people diagnosed with diabetes and attending screening were visually impaired (95% confidence intervals (CI) 3.2% to 3.5%) and 0.39% severely visually impaired (0.33% to 0.44%). Blacks and South Asians had a higher prevalence of visual impairment (directly age standardised prevalence 4.6%, 95% CI 4.0% to 5.1% and 6.9%, 95% CI 5.8% to 8.0% respectively) compared to white people (3.3%, 95% CI 3.1% to 3.5%). Visual loss was also more prevalent with increasing age, type 1 diabetes and in people living in Yorkshire. Visual impairment remains an important public health problem in people with diabetes, and is more prevalent in the minority ethnic groups in the UK.

[Symptoms and lesion localization in visual agnosia].

PubMed

Suzuki, Kyoko

2004-11-01

There are two cortical visual processing streams, the ventral and dorsal stream. The ventral visual stream plays the major role in constructing our perceptual representation of the visual world and the objects within it. Disturbance of visual processing at any stage of the ventral stream could result in impairment of visual recognition. Thus we need systematic investigations to diagnose visual agnosia and its type. Two types of category-selective visual agnosia, prosopagnosia and landmark agnosia, are different from others in that patients could recognize a face as a face and buildings as buildings, but could not identify an individual person or building. Neuronal bases of prosopagnosia and landmark agnosia are distinct. Importance of the right fusiform gyrus for face recognition was confirmed by both clinical and neuroimaging studies. Landmark agnosia is related to lesions in the right parahippocampal gyrus. Enlarged lesions including both the right fusiform and parahippocampal gyri can result in prosopagnosia and landmark agnosia at the same time. Category non-selective visual agnosia is related to bilateral occipito-temporal lesions, which is in agreement with the results of neuroimaging studies that revealed activation of the bilateral occipito-temporal during object recognition tasks.

Prevalence of vision impairment and refractive error in school children in Ba Ria – Vung Tau province, Vietnam

PubMed Central

Paudel, Prakash; Ramson, Prasidh; Naduvilath, Thomas; Wilson, David; Phuong, Ha Thanh; Ho, Suit M; Giap, Nguyen V

2014-01-01

Background To assess the prevalence of vision impairment and refractive error in school children 12–15 years of age in Ba Ria – Vung Tau province, Vietnam. Design Prospective, cross-sectional study. Participants 2238 secondary school children. Methods Subjects were selected based on stratified multistage cluster sampling of 13 secondary schools from urban, rural and semi-urban areas. The examination included visual acuity measurements, ocular motility evaluation, cycloplegic autorefraction, and examination of the external eye, anterior segment, media and fundus. Main Outcome Measures Visual acuity and principal cause of vision impairment. Results The prevalence of uncorrected and presenting visual acuity ≤6/12 in the better eye were 19.4% (95% confidence interval, 12.5–26.3) and 12.2% (95% confidence interval, 8.8–15.6), respectively. Refractive error was the cause of vision impairment in 92.7%, amblyopia in 2.2%, cataract in 0.7%, retinal disorders in 0.4%, other causes in 1.5% and unexplained causes in the remaining 2.6%. The prevalence of vision impairment due to myopia in either eye (–0.50 diopter or greater) was 20.4% (95% confidence interval, 12.8–28.0), hyperopia (≥2.00 D) was 0.4% (95% confidence interval, 0.0–0.7) and emmetropia with astigmatism (≥0.75 D) was 0.7% (95% confidence interval, 0.2–1.2). Vision impairment due to myopia was associated with higher school grade and increased time spent reading and working on a computer. Conclusions Uncorrected refractive error, particularly myopia, among secondary school children in Vietnam is a major public health problem. School-based eye health initiative such as refractive error screening is warranted to reduce vision impairment. PMID:24299145

Prevalence of vision impairment and refractive error in school children in Ba Ria - Vung Tau province, Vietnam.

PubMed

Paudel, Prakash; Ramson, Prasidh; Naduvilath, Thomas; Wilson, David; Phuong, Ha Thanh; Ho, Suit M; Giap, Nguyen V

2014-04-01

To assess the prevalence of vision impairment and refractive error in school children 12-15 years of age in Ba Ria - Vung Tau province, Vietnam. Prospective, cross-sectional study. 2238 secondary school children. Subjects were selected based on stratified multistage cluster sampling of 13 secondary schools from urban, rural and semi-urban areas. The examination included visual acuity measurements, ocular motility evaluation, cycloplegic autorefraction, and examination of the external eye, anterior segment, media and fundus. Visual acuity and principal cause of vision impairment. The prevalence of uncorrected and presenting visual acuity ≤6/12 in the better eye were 19.4% (95% confidence interval, 12.5-26.3) and 12.2% (95% confidence interval, 8.8-15.6), respectively. Refractive error was the cause of vision impairment in 92.7%, amblyopia in 2.2%, cataract in 0.7%, retinal disorders in 0.4%, other causes in 1.5% and unexplained causes in the remaining 2.6%. The prevalence of vision impairment due to myopia in either eye (-0.50 diopter or greater) was 20.4% (95% confidence interval, 12.8-28.0), hyperopia (≥2.00 D) was 0.4% (95% confidence interval, 0.0-0.7) and emmetropia with astigmatism (≥0.75 D) was 0.7% (95% confidence interval, 0.2-1.2). Vision impairment due to myopia was associated with higher school grade and increased time spent reading and working on a computer. Uncorrected refractive error, particularly myopia, among secondary school children in Vietnam is a major public health problem. School-based eye health initiative such as refractive error screening is warranted to reduce vision impairment. © 2013 The Authors. Clinical & Experimental Ophthalmology published by Wiley Publishing Asia Pty Ltd on behalf of Royal Australian and New Zealand College of Ophthalmologists.

The occurrence of visual and cognitive impairment, and eye diseases in the super-elderly in Japan: a cross-sectional single-center study.

PubMed

Fukuoka, Hideki; Nagaya, Masahiro; Toba, Kenji

2015-10-29

The current state of eye diseases and treatments in the elderly as well as the relationships between dementia and systemic diseases remain unclear. Therefore, this study evaluated the prevalence of eye diseases, visual impairment, cognitive impairment, and falls (which are an important health issue and are considered one of the Geriatric Giants) in super-elderly people in Japan. The subjects were 31 elderly people (62 eyes; mean age: 84.6 ± 8.8 years; age range 61-98 years) who were admitted to a geriatric health services facility. Eye treatment status, systemic diseases, dementia, and recent falls were investigated. Eye examinations including vision and intraocular pressure measurement, and slit-lamp biomicroscopy were conducted. Mean best corrected visual acuity (logMAR) was 0.51 ± 0.56, and mean intraocular pressure was 13.7 ± 3.5 mmHg. Approximately half of the subjects exhibited excavation of the optic nerve head including cataracts and glaucoma. Ten subjects had visual impairment (i.e., visual acuity of the eye with the better vision <20/40). The mean Hasegawa dementia scale scores between the visually impaired and non-visually impaired groups were 10.2 ± 6 and 16 ± 8 points, respectively (p < 0.05). Furthermore, 70% of subjects with visual impairment experienced a fall in the past year compared to 48% of those without visual impairment, although the difference was not significant. Regarding systemic diseases, there were 6, 5, and 15 cases of diabetes, hyperlipidemia, and hypertension, respectively. There was no significant difference between these systemic diseases and visual function after adjusted for age and gender. The percentages of patients with age-related eye diseases and poor visual acuity in a geriatric health services facility were extremely high. Compared to those without visual impairment, those with visual impairment had lower dementia scores and a higher rate of falls.

Association of Visual Impairment and All-Cause 10-Year Mortality Among Indigenous Australian Individuals Within Central Australia: The Central Australian Ocular Health Study.

PubMed

Ng, Soo Khai; Kahawita, Shyalle; Andrew, Nicholas Howard; Henderson, Tim; Craig, Jamie Evan; Landers, John

2018-05-01

It is well established from different population-based studies that visual impairment is associated with increased mortality rate. However, to our knowledge, the association of visual impairment with increased mortality rate has not been reported among indigenous Australian individuals. To assess the association between visual impairment and 10-year mortality risk among the remote indigenous Australian population. Prospective cohort study recruiting indigenous Australian individuals from 30 remote communities located within the central Australian statistical local area over a 36-month period between July 2005 and June 2008. The data were analyzed in January 2017. Visual acuity, slitlamp biomicroscopy, and fundus examination were performed on all patients at recruitment. Visual impairment was defined as a visual acuity of less than 6/12 in the better eye. Mortality rate and mortality cause were obtained at 10 years, and statistical analyses were performed. Hazard ratios for 10-year mortality with 95% confidence intervals are presented. One thousand three hundred forty-seven patients were recruited from a total target population number of 2014. The mean (SD) age was 56 (11) years, and 62% were women. The total all-cause mortality was found to be 29.3% at 10 years. This varied from 21.1% among those without visual impairment to 48.5% among those with visual impairment. After adjustment for age, sex, and the presence of diabetes and hypertension, those with visual impairment were 40% more likely to die (hazard ratio, 1.40; 95% CI, 1.16-1.70; P = .001) during the 10-year follow-up period compared with those with normal vision. Bilateral visual impairment among remote indigenous Australian individuals was associated with 40% higher 10-year mortality risk compared with those who were not visually impaired. Resource allocation toward improving visual acuity may therefore aid in closing the gap in mortality outcomes between indigenous and nonindigenous Australian individuals.

Rewarded visual items capture attention only in heterogeneous contexts.

PubMed

Feldmann-Wüstefeld, Tobias; Brandhofer, Ruben; Schubö, Anna

2016-07-01

Reward is known to affect visual search performance. Rewarding targets can increase search performance, whereas rewarding distractors can decrease search performance. We used subcomponents of the N2pc in the event-related EEG, the NT (target negativity) and ND /PD (distractor negativity/positivity), in a visual search task to disentangle target and distractor processing related to reward. The visual search task comprised homogeneous and heterogeneous contexts in which a target and a colored distractor were embedded. After each correct trial, participants were given a monetary reward that depended on the color of the distractor. We found longer response times for displays with high-reward distractors compared to displays with low-reward distractors, indicating reward-induced interference, however, only for heterogeneous contexts. The NT component, indicative of attention deployment to the target, showed that target selection was impaired by high-reward distractors, regardless of the context homogeneity. Processing of distractors was not affected by reward in homogeneous contexts. In heterogeneous contexts, however, high-reward distractors were more likely to capture attention (ND ) and required more effort to be suppressed (PD ) than low-reward distractors. In sum the results showed that, despite the fact that target selection is impaired by high-reward distractors in both homogeneous and heterogeneous background contexts, high-reward distractors capture attention only in scenarios that foster attentional capture. © 2016 Society for Psychophysiological Research.

A Comparison of Social Skills in Turkish Children with Visual Impairments, Children with Intellectual Impairments and Typically Developing Children

ERIC Educational Resources Information Center

Ozkubat, Ufuk; Ozdemir, Selda

2014-01-01

The purpose of this study was to compare the social skills of five groups of children: children with visual impairments attending inclusive education schools, children with visual impairments attending schools for the blind, children with intellectual impairments attending inclusive education schools, children with intellectual impairments…

Prevelence and causes of visual impairment and blindness in older adults in an area of India with a high cataract surgical rate.

PubMed

Murthy, Gudlavalleti V S; Vashist, Praveen; John, Neena; Pokharel, Gopal; Ellwein, Leon B

2010-08-01

The cataract surgical rate (CSR) in Gujarat, India is reported to be above 10,000 per million population. This study was conducted to investigate the prevalence and causes of vision impairment/blindness among older adults in a high CSR area. Geographically defined cluster sampling was used in randomly selecting persons >or= 50 years of age in Navsari district. Subjects in 35 study clusters were enumerated and invited for measurement of presenting and best-corrected visual acuity and an ocular examination. The principal cause was identified for eyes with presenting visual acuity < 20/32. A total of 5158 eligible persons were enumerated and 4738 (91.9%) examined. Prevalence of presenting visual impairment < 20/63 to 20/200 in the better eye was 29.3% (95% confidence interval [CI]: 27.5-31.2) and 13.5% (95% CI: 12.0-14.9) with best correction. The prevalence of presenting bilateral blindness (< 20/200) was 6.9% (95% CI: 5.7-8.1), and 3.1% (95% CI: 2.5-3.7) with best correction. Presenting and best-corrected blindness were both associated with older age and illiteracy; gender and rural/urban residence were not significant. Cataract in one or both eyes was the main cause of bilateral blindness (82.6%), followed by retinal disorders (8.9%). Cataract (50.3%) and refractive error (35.4%) were the main causes in eyes with vision acuity < 20/63 to 20/200, and refractive error (86.6%) in eyes with acuity < 20/32 to 20/63. Visual impairment and blindness is a significant problem among the elderly in Gujarat. Despite a reportedly high CSR, cataract remains the predominant cause of blindness.

Exploring the patient perspective of fatigue in adults with visual impairment: a qualitative study.

PubMed

Schakel, Wouter; Bode, Christina; van der Aa, Hilde P A; Hulshof, Carel T J; Bosmans, Judith E; van Rens, Gerardus H M B; van Nispen, Ruth M A

2017-08-03

Fatigue is an often mentioned symptom by patients with irreversible visual impairment. This study explored the patient perspective of fatigue in visually impaired adults with a focus on symptoms of fatigue, causes, consequences and coping strategies. Two large Dutch low vision multidisciplinary rehabilitation organisations. 16 visually impaired adults with severe symptoms of fatigue selected by purposive sampling. A qualitative study involving semistructured interviews. A total of four first-level codes were top-down predetermined in correspondence with the topics of the research question. Verbatim transcribed interviews were analysed with a combination of a deductive and inductive approach using open and axial coding. Participants often described the symptoms of fatigue as a mental, daily and physical experience. The most often mentioned causes of fatigue were a high cognitive load, the intensity and amount of activities, the high effort necessary to establish visual perception, difficulty with light intensity and negative cognitions. Fatigue had the greatest impact on the ability to carry out social roles and participation, emotional functioning and cognitive functioning. The most common coping strategies were relaxation, external support, socialising and physical exercise and the acceptance of fatigue. Our results indicate that low vision-related fatigue is mainly caused by population specific determinants that seem different from the fatigue experience described in studies with other patient populations. Fatigue may be central to the way patients react, adapt and compensate to the consequences of vision loss. These findings indicate a need for future research aimed at interventions specifically tailored to the unique aspects of fatigue related to vision loss. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Mechanisms underlying selecting objects for action

PubMed Central

Wulff, Melanie; Laverick, Rosanna; Humphreys, Glyn W.; Wing, Alan M.; Rotshtein, Pia

2015-01-01

We assessed the factors which affect the selection of objects for action, focusing on the role of action knowledge and its modulation by distracters. Fourteen neuropsychological patients and 10 healthy aged-matched controls selected pairs of objects commonly used together among distracters in two contexts: with real objects and with pictures of the same objects presented sequentially on a computer screen. Across both tasks, semantically related distracters led to slower responses and more errors than unrelated distracters and the object actively used for action was selected prior to the object that would be passively held during the action. We identified a sub-group of patients (N = 6) whose accuracy was 2SDs below the controls performances in the real object task. Interestingly, these impaired patients were more affected by the presence of unrelated distracters during both tasks than intact patients and healthy controls. Note that the impaired patients had lesions to left parietal, right anterior temporal and bilateral pre-motor regions. We conclude that: (1) motor procedures guide object selection for action, (2) semantic knowledge affects action-based selection, (3) impaired action decision making is associated with the inability to ignore distracting information and (4) lesions to either the dorsal or ventral visual stream can lead to deficits in making action decisions. Overall, the data indicate that impairments in everyday tasks can be evaluated using a simulated computer task. The implications for rehabilitation are discussed. PMID:25954177

Evidence for selective inhibitory impairment in individuals with autism spectrum disorder.

PubMed

Christ, Shawn E; Kester, Lindsay E; Bodner, Kimberly E; Miles, Judith H

2011-11-01

The social and communicative challenges faced by individuals with autism spectrum disorder (ASD) are often compounded by additional difficulties with executive function. It remains unclear, however, to what the extent individuals with ASD experienced impairment in inhibitory control. The objective of the present study was to assess the three main subtypes of executive inhibitory control within a single ASD sample thus providing new insight into the unique ASD-related pattern of sparing and impairment observed across different aspects of inhibitory control. A sample of 28 children with ASD (mean age = 13.1 years) and a comparison group of 49 neurologically uncompromised children (mean age = 13.3 years) participated. A prepotent response inhibition task, a flanker visual filtering task, and a proactive interference memory task were used to evaluate prepotent response inhibition, resistance to distracter interference, and resistance to proactive interference, respectively. After accounting for individual differences in noninhibition abilities (e.g., processing speed) and overall level of functioning, there was no evidence of group-related differences in inhibitory performance on the prepotent response inhibition test or proactive interference test. ASD-related impairments in inhibitory control were evident, however, on the flanker visual filtering task. Taken together, the present findings indicate that ASD is associated with impairments in some, but not all, aspects of inhibitory control. Individuals with ASD appear to have difficulty ignoring distracting visual information, but prepotent response inhibition and resistance to proactive interference are relatively intact. The current findings also provide support for a multitype model of inhibitory control.

A Novel Method of Notification to Profile Childhood Visual Impairment in Scotland to Meet the Needs of Children with Visual Impairment

ERIC Educational Resources Information Center

Ravenscroft, John; Blaikie, Andrew; Macewen, Caroline; O'Hare, Anne; Creswell, Lyn; Dutton, Gordon N.

2008-01-01

The purpose of this study is to pilot a new notification system for children with visual impairment (VI) and describe the initial summary findings. A system of notification of children in Scotland with VI was established. Information concerning this system was distributed to professionals working with visually impaired children to forward to…

The Investigation of Physical Performance Status of Visually and Hearing Impaired Applying Judo Training Program

ERIC Educational Resources Information Center

Karakoc, Onder

2016-01-01

It was aimed to investigate the physical performances of visually and hearing impaired doing judo training in this study. 32 male athletes, who were doing judo training, volunteer and, visually and hearing impaired, participated in this study. The investigation was applied to visually impaired (N = 12, mean ± SD; age: 25.75 ± 3.55 years, height:…

The Influence of Manifest Strabismus and Stereoscopic Vision on Non-Verbal Abilities of Visually Impaired Children

ERIC Educational Resources Information Center

Gligorovic, Milica; Vucinic, Vesna; Eskirovic, Branka; Jablan, Branka

2011-01-01

This research was conducted in order to examine the influence of manifest strabismus and stereoscopic vision on non-verbal abilities of visually impaired children aged between 7 and 15. The sample included 55 visually impaired children from the 1st to the 6th grade of elementary schools for visually impaired children in Belgrade. RANDOT stereotest…

The Effect of Gender and Level of Vision on the Physical Activity Level of Children and Adolescents with Visual Impairment

ERIC Educational Resources Information Center

Aslan, Ummuhan Bas; Calik, Bilge Basakci; Kitis, Ali

2012-01-01

This study was planned in order to determine physical activity levels of visually impaired children and adolescents and to investigate the effect of gender and level of vision on physical activity level in visually impaired children and adolescents. A total of 30 visually impaired children and adolescents (16 low vision and 14 blind) aged between…

Adapting for Impaired Patrons.

ERIC Educational Resources Information Center

Schuyler, Michael

1999-01-01

Describes how a library, with an MCI Corporation grant, approached the process of setting up computers for the visually impaired. Discusses preparations, which included hiring a visually-impaired user as a consultant and contacting the VIP (Visually Impaired Persons) group; equipment; problems with the graphical user interface; and training.…

Are Hemianopic Reading and Visual Exploration Impairments Visually Elicited? New Insights from Eye Movements in Simulated Hemianopia

ERIC Educational Resources Information Center

Schuett, Susanne; Kentridge, Robert W.; Zihl, Josef; Heywood, Charles A.

2009-01-01

Hemianopic reading and visual exploration impairments are well-known clinical phenomena. Yet, it is unclear whether they are primarily caused by the hemianopic visual field defect itself or by additional brain injury preventing efficient spontaneous oculomotor adaptation. To establish the extent to which these impairments are visually elicited we…

Visual impairment is associated with physical and mental comorbidities in older adults: a cross-sectional study.

PubMed

Court, Helen; McLean, Gary; Guthrie, Bruce; Mercer, Stewart W; Smith, Daniel J

2014-10-17

Visual impairment is common in older people and the presence of additional health conditions can compromise health and rehabilitation outcomes. A small number of studies have suggested that comorbities are common in visual impairment; however, those studies have relied on self-report and have assessed a relatively limited number of comorbid conditions. We conducted a cross-sectional analysis of a dataset of 291,169 registered patients (65-years-old and over) within 314 primary care practices in Scotland, UK. Visual impairment was identified using Read Code ever recorded for blindness and/or low vision (within electronic medical records). Prevalence, odds ratios (from prevalence rates standardised by stratifying individuals by age groups (65 to 69 years; 70 to 74; 75 to 79; 80 to 84; and 85 and over), gender and deprivation quintiles) and 95% confidence intervals (95% CI) of 37 individual chronic physical/mental health conditions and total number of conditions were calculated and compared for those with visual impairment to those without. Twenty seven of the 29 physical health conditions and all eight mental health conditions were significantly more likely to be recorded for individuals with visual impairment compared to individuals without visual impairment, after standardising for age, gender and social deprivation. Individuals with visual impairment were also significantly more likely to have more comorbidities (for example, five or more conditions (odds ratio (OR) 2.05 95% CI 1.94 to 2.18)). Patients aged 65 years and older with visual impairment have a broad range of physical and mental health comorbidities compared to those of the same age without visual impairment, and are more likely to have multiple comorbidities. This has important implications for clinical practice and for the future design of integrated services to meet the complex needs of patients with visual impairment, for example, embedding depression and hearing screening within eye care services.

[Comparison of visual impairment caused by trachoma in China between 1978 and 2006].

PubMed

Hu, Ailian; Cai, Xiaogu; Qiao, Liya; Zhang, Ye; Zhang, Xu; Sun, Baochen; Wang, Ningli

2015-10-01

To understand the distribution of visual impairment caused by trachoma in China and provide evidences for evaluation of eliminating blinding trachoma in China in the mission of Vision 2020. Sampling study. The results from the first year 1987 and second (year 2006) national sampling surveys of disabled persons were analyzed. Chi-square test was performed using SAS 9.30 to analyze the rates of visual impairment caused by trachoma in different groups. Unifactor and multifactor analyses were applied to analyze the relevance between visual impairment caused by trachoma and risk factors, including gender and age. The rate of visual impairment caused by trachoma was 102.01 persons/100 000 in 1987 and 17.62 persons/100 000 in 2006. The percentage of trachoma in all kinds of visual impairment was 14.25% in 1987 and 1.87% in 2006, and the difference was significant (F = 1 382.6, P < 0.01). Spatial aggregation was obvious in visual impairment caused by trachoma. H-aggregation areas included Hubei, Sichuan, Anhui, Shannxi, Guizhou, Hunan provinces and Chongqing Municipality. Survival time without trachoma between 1987 and 2006 was significantly different (F = 2 745.9, P < 0.01). The rate and risk of visual impairment caused by trachoma increased with age. Except the group of > 85 years, the rate of visual impairment caused by trachoma in all age groups in 1987 was significantly higher than that in 2006. The risk of visual impairment caused by trachoma in 1987 was 5.8 times that in 2006. If the other risk factors were not involved, the risk in 1987 was 8.75 times that in 2006. The risk in females was twice that in males. Both, the rate and risk of visual impairment caused by trachoma were significantly reduced in China. Impressive progresses were achieved in trachoma prevention and control.

Mobility scooter driving ability in visually impaired individuals.

PubMed

Cordes, Christina; Heutink, Joost; Brookhuis, Karel A; Brouwer, Wiebo H; Melis-Dankers, Bart J M

2018-06-01

To investigate how well visually impaired individuals can learn to use mobility scooters and which parts of the driving task deserve special attention. A mobility scooter driving skill test was developed to compare driving skills (e.g. reverse driving, turning) between 48 visually impaired (very low visual acuity = 14, low visual acuity = 10, peripheral field defects = 11, multiple visual impairments = 13) and 37 normal-sighted controls without any prior experience with mobility scooters. Performance on this test was rated on a three-point scale. Furthermore, the number of extra repetitions on the different elements were noted. Results showed that visually impaired participants were able to gain sufficient driving skills to be able to use mobility scooters. Participants with visual field defects combined with low visual acuity showed most problems learning different skills and needed more training. Reverse driving and stopping seemed to be most difficult. The present findings suggest that visually impaired individuals are able to learn to drive mobility scooters. Mobility scooter allocators should be aware that these individuals might need more training on certain elements of the driving task. Implications for rehabilitation Visual impairments do not necessarily lead to an inability to acquire mobility scooter driving skills. Individuals with peripheral field defects (especially in combination with reduced visual acuity) need more driving ability training compared to normal-sighted people - especially to accomplish reversing. Individual assessment of visually impaired people is recommended, since participants in this study showed a wide variation in ability to learn driving a mobility scooter.

Age-Related Interference between the Selection of Input-Output Modality Mappings and Postural Control—a Pilot Study

PubMed Central

Stelzel, Christine; Schauenburg, Gesche; Rapp, Michael A.; Heinzel, Stephan; Granacher, Urs

2017-01-01

Age-related decline in executive functions and postural control due to degenerative processes in the central nervous system have been related to increased fall-risk in old age. Many studies have shown cognitive-postural dual-task interference in old adults, but research on the role of specific executive functions in this context has just begun. In this study, we addressed the question whether postural control is impaired depending on the coordination of concurrent response-selection processes related to the compatibility of input and output modality mappings as compared to impairments related to working-memory load in the comparison of cognitive dual and single tasks. Specifically, we measured total center of pressure (CoP) displacements in healthy female participants aged 19–30 and 66–84 years while they performed different versions of a spatial one-back working memory task during semi-tandem stance on an unstable surface (i.e., balance pad) while standing on a force plate. The specific working-memory tasks comprised: (i) modality compatible single tasks (i.e., visual-manual or auditory-vocal tasks), (ii) modality compatible dual tasks (i.e., visual-manual and auditory-vocal tasks), (iii) modality incompatible single tasks (i.e., visual-vocal or auditory-manual tasks), and (iv) modality incompatible dual tasks (i.e., visual-vocal and auditory-manual tasks). In addition, participants performed the same tasks while sitting. As expected from previous research, old adults showed generally impaired performance under high working-memory load (i.e., dual vs. single one-back task). In addition, modality compatibility affected one-back performance in dual-task but not in single-task conditions with strikingly pronounced impairments in old adults. Notably, the modality incompatible dual task also resulted in a selective increase in total CoP displacements compared to the modality compatible dual task in the old but not in the young participants. These results suggest that in addition to effects of working-memory load, processes related to simultaneously overcoming special linkages between input- and output modalities interfere with postural control in old but not in young female adults. Our preliminary data provide further evidence for the involvement of cognitive control processes in postural tasks. PMID:28484411

Epidemiology, aetiology and management of visual impairment in children.

PubMed

Solebo, Ameenat Lola; Rahi, Jugnoo

2014-04-01

An estimated 19 million of the world's children are visually impaired, while 1.4 million are blind. Using the UK as a model for high income countries, from a population-based incidence study, the annual cumulative incidence of severe visual impairment/blindness (SVL/BL) is estimated to be 6/10 000 by age 15 years, with the incidence being highest in the first year of life. The population of visually impaired children within high, middle and lower income countries differ considerably between and within countries. The numerous and mainly uncommon disorders which can cause impaired vision result in heterogeneous population which includes a substantial proportion (for SVI/BL, the majority) of children with additional systemic disorders or impairments whose needs differ substantially from those with isolated vision impairment. Paediatricians and other paediatric professionals have a key role in early detection and multidisciplinary management to minimise the impact of visual impairment (VI) in childhood.

Emotional and behavioural problems in children with visual impairment, intellectual and multiple disabilities.

PubMed

Alimovic, S

2013-02-01

Children with multiple impairments have more complex developmental problems than children with a single impairment. We compared children, aged 4 to 11 years, with intellectual disability (ID) and visual impairment to children with single ID, single visual impairment and typical development on 'Child Behavior Check List/4-18' (CBCL/4-18), Parent Report. Children with ID and visual impairment had more emotional and behavioural problems than other groups of children: with single impairment and with typical development (F = 23.81; d.f.1/d.f.2 = 3/156; P < 0.001). All children with special needs had more emotional and behavioural problems than children with typical development. The highest difference was found in attention problems syndrome (F = 30.45; d.f.1/d.f.2 = 3/156; P < 0.001) where all groups of children with impairments had more problems. Children with visual impairment, with and without ID, had more somatic complaints than children with normal vision. Intellectual disability had greater influence on prevalence and kind of emotional and behavioural problems in children than visual impairment. © 2012 The Author. Journal of Intellectual Disability Research © 2012 Blackwell Publishing Ltd.

The prevalence and risk factors of visual impairment among the elderly in Eastern Taiwan.

PubMed

Wang, Wen-Li; Chen, Nancy; Sheu, Min-Muh; Wang, Jen-Hung; Hsu, Wen-Lin; Hu, Yih-Jin

2016-09-01

Visual impairment is associated with disability and poor quality of life. This study aimed to investigate the prevalence and associated risk factors of visual impairment among the suburban elderly in Eastern Taiwan. The cross-sectional research was conducted from April 2012 to August 2012. The ocular condition examination took place in suburban areas of Hualien County. Medical records from local infirmaries and questionnaires were utilized to collect demographic data and systemic disease status. Logistic regression models were used for the simultaneous analysis of the association between the prevalence of visual impairment and risk factors. Six hundred and eighty-one residents participated in this project. The mean age of the participants was 71.4±7.3 years. The prevalence of vision impairment (better eye<6/18) was 11.0%. Refractive error and cataract were the main causes of vision impairment. Logistic regression analysis showed that people aged 65-75 years had a 3.8 times higher risk of developing visual impairment (p=0.021), while the odds ratio of people aged > 75 years was 10.0 (p<0.001). In addition, patients with diabetic retinopathy had a 3.7 times higher risk of developing visual impairment (p=0.002), while the odds ratio of refractive error was 0.36 (p<0.001). The prevalence of visual impairment was relatively high compared with previous studies. Diabetic retinopathy was an important risk factor of visual impairment; by contrast, refractive error was beneficial to resist visual impairment. Therefore, regular screening of ocular condition and early intervention might aid in the prevention of avoidable vision loss. Copyright © 2016. Published by Elsevier Taiwan.

Living Independently: Exploring the Experiences of Visually Impaired People Living in Age-Related and Lifetime Housing Through Qualitative Synthesis.

PubMed

Rooney, Clíona; Hadjri, Karim; Faith, Verity; Rooney, Máirin; McAllister, Keith; Craig, Cathy

2017-01-01

The aim of this study is to gain a deeper understanding of the experiences of visually impaired older people living independently at home. As populations are aging globally, there is now an increase in the prevalence of visual impairment. That means for ongoing and future aging-in-place strategies that seek to enable older people to remain independent for longer, more attention needs to be given to the needs of those with visual impairment. As people develop visual impairment, they use adaptive strategies including modifying long-term homes or relocating to more suitable accommodation. In the United Kingdom, aging-in-place strategies include employing statutory lifetime home standards (LTHS) in the home or relocating to sheltered housing to live independently with support available if required. To get a better understanding of the needs of the visually impaired in the home, 12 interviews with six visually impaired occupants of LTHS homes and six from sheltered accommodation were analyzed separately using interpretative phenomenological analysis. Secondly, qualitative synthesis was used to further analyze themes generated from both samples before interview results were conceptualized in two superordinate concepts, namely, "negotiating priorities" and "understanding visual impairment." Participants from both groups had similar needs and were willing to compromise by living with some negative features. Those who coped well with moving utilized various resources. These findings will shed more understanding on providing good quality housing for those with visual impairment wanting to live either independently or within healthcare home environments.

Social inequalities in blindness and visual impairment: A review of social determinants

PubMed Central

Ulldemolins, Anna Rius; Lansingh, Van C; Valencia, Laura Guisasola; Carter, Marissa J; Eckert, Kristen A

2012-01-01

Health inequities are related to social determinants based on gender, socioeconomic status, ethnicity, race, living in a specific geographic region, or having a specific health condition. Such inequities were reviewed for blindness and visual impairment by searching for studies on the subject in PubMed from 2000 to 2011 in the English and Spanish languages. The goal of this article is to provide a current review in understanding how inequities based specifically on the aforementioned social determinants on health influence the prevalence of visual impairment and blindness. With regards to gender inequality, women have a higher prevalence of visual impairment and blindness, which cannot be only reasoned based on age or access to service. Socioeconomic status measured as higher income, higher educational status, or non-manual occupational social class was inversely associated with prevalence of blindness or visual impairment. Ethnicity and race were associated with visual impairment and blindness, although there is general confusion over this socioeconomic position determinant. Geographic inequalities and visual impairment were related to income (of the region, nation or continent), living in a rural area, and an association with socioeconomic and political context was suggested. While inequalities related to blindness and visual impairment have rarely been specifically addressed in research, there is still evidence of the association of social determinants and prevalence of blindness and visual impairment. Additional research should be done on the associations with intermediary determinants and socioeconomic and political context. PMID:22944744

The Impact of Visual Impairment on Perceived School Climate

ERIC Educational Resources Information Center

Schade, Benjamin; Larwin, Karen H.

2015-01-01

The current investigation examines whether visual impairment has an impact on a student's perception of the school climate. Using a large national sample of high school students, perceptions were examined for students with vision impairment relative to students with no visual impairments. Three factors were examined: self-reported level of…

Grief and Needs of Adults with Acquired Visual Impairments

ERIC Educational Resources Information Center

Murray, Shirley A.; McKay, Robert C.; Nieuwoudt, Johan M.

2010-01-01

This report aims to illuminate the complex phenomenon of grief and the needs experienced throughout the time course of their impairments by adults with acquired visual impairments. The study applied a phenomenological research strategy using 10 case studies of South African adults, visually impaired within and beyond six years. Qualitative…

Attention modulates trans-saccadic integration.

PubMed

Stewart, Emma E M; Schütz, Alexander C

2018-01-01

With every saccade, humans must reconcile the low resolution peripheral information available before a saccade, with the high resolution foveal information acquired after the saccade. While research has shown that we are able to integrate peripheral and foveal vision in a near-optimal manner, it is still unclear which mechanisms may underpin this important perceptual process. One potential mechanism that may moderate this integration process is visual attention. Pre-saccadic attention is a well documented phenomenon, whereby visual attention shifts to the location of an upcoming saccade before the saccade is executed. While it plays an important role in other peri-saccadic processes such as predictive remapping, the role of attention in the integration process is as yet unknown. This study aimed to determine whether the presentation of an attentional distractor during a saccade impaired trans-saccadic integration, and to measure the time-course of this impairment. Results showed that presenting an attentional distractor impaired integration performance both before saccade onset, and during the saccade, in selected subjects who showed integration in the absence of a distractor. This suggests that visual attention may be a mechanism that facilitates trans-saccadic integration. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

[Visual impairment and blindness in children in a Malawian school for the blind].

PubMed

Schulze Schwering, M; Nyrenda, M; Spitzer, M S; Kalua, K

2013-08-01

The aim of this study was to determine the anatomic sites of severe visual impairment and blindness in children in an integrated school for the blind in Malawi, and to compare the results with those of previous Malawian blind school studies. Children attending an integrated school for the blind in Malawi were examined in September 2011 using the standard WHO/PBL eye examination record for children with blindness and low vision. Visual acuity [VA] of the better eye was classified using the standardised WHO reporting form. Fifty-five pupils aged 6 to 19 years were examined, 39 (71 %) males, and 16 (29 %) females. Thirty eight (69%) were blind [BL], 8 (15 %) were severely visually impaired [SVI], 8 (15 %) visually impaired [VI], and 1 (1.8 %) was not visually impaired [NVI]. The major anatomic sites of visual loss were optic nerve (16 %) and retina (16 %), followed by lens/cataract (15 %), cornea (11 %) and lesions of the whole globe (11 %), uveal pathologies (6 %) and cortical blindness (2 %). The exact aetiology of VI or BL could not be determined in most children. Albinism accounted for 13 % (7/55) of the visual impairments. 24 % of the cases were considered to be potentially avoidable: refractive amblyopia among pseudophakic patients and corneal scaring. Optic atrophy, retinal diseases (mostly albinism) and cataracts were the major causes of severe visual impairment and blindness in children in an integrated school for the blind in Malawi. Corneal scarring was now the fourth cause of visual impairment, compared to being the commonest cause 35 years ago. Congenital cataract and its postoperative outcome were the commonest remedial causes of visual impairment. Georg Thieme Verlag KG Stuttgart · New York.

Effective Connectivity from Early Visual Cortex to Posterior Occipitotemporal Face Areas Supports Face Selectivity and Predicts Developmental Prosopagnosia

PubMed Central

Garrido, Lucia; Driver, Jon; Dolan, Raymond J.; Duchaine, Bradley C.; Furl, Nicholas

2016-01-01

Face processing is mediated by interactions between functional areas in the occipital and temporal lobe, and the fusiform face area (FFA) and anterior temporal lobe play key roles in the recognition of facial identity. Individuals with developmental prosopagnosia (DP), a lifelong face recognition impairment, have been shown to have structural and functional neuronal alterations in these areas. The present study investigated how face selectivity is generated in participants with normal face processing, and how functional abnormalities associated with DP, arise as a function of network connectivity. Using functional magnetic resonance imaging and dynamic causal modeling, we examined effective connectivity in normal participants by assessing network models that include early visual cortex (EVC) and face-selective areas and then investigated the integrity of this connectivity in participants with DP. Results showed that a feedforward architecture from EVC to the occipital face area, EVC to FFA, and EVC to posterior superior temporal sulcus (pSTS) best explained how face selectivity arises in both controls and participants with DP. In this architecture, the DP group showed reduced connection strengths on feedforward connections carrying face information from EVC to FFA and EVC to pSTS. These altered network dynamics in DP contribute to the diminished face selectivity in the posterior occipitotemporal areas affected in DP. These findings suggest a novel view on the relevance of feedforward projection from EVC to posterior occipitotemporal face areas in generating cortical face selectivity and differences in face recognition ability. SIGNIFICANCE STATEMENT Areas of the human brain showing enhanced activation to faces compared to other objects or places have been extensively studied. However, the factors leading to this face selectively have remained mostly unknown. We show that effective connectivity from early visual cortex to posterior occipitotemporal face areas gives rise to face selectivity. Furthermore, people with developmental prosopagnosia, a lifelong face recognition impairment, have reduced face selectivity in the posterior occipitotemporal face areas and left anterior temporal lobe. We show that this reduced face selectivity can be predicted by effective connectivity from early visual cortex to posterior occipitotemporal face areas. This study presents the first network-based account of how face selectivity arises in the human brain. PMID:27030766

The impact of visual impairment on self-reported visual functioning in Latinos: The Los Angeles Latino Eye Study.

PubMed

Globe, Denise R; Wu, Joanne; Azen, Stanley P; Varma, Rohit

2004-06-01

To assess the association between presenting binocular visual acuity (VA) and self-reported visual function as measured by the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). A population-based, prevalence study of eye disease in Latinos 40 years and older residing in La Puente, California (Los Angeles Latino Eye Study [LALES]). Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in La Puente. All participants completed a standardized interview, including the NEI-VFQ-25 to measure visual functioning, and a detailed eye examination. Two definitions of visual impairment were used: (1) presenting binocular distance VA of 20/40 or worse and (2) presenting binocular distance VA worse than 20/40. Analysis of variance was used to determine any systematic differences in mean NEI-VFQ-25 scores by visual impairment. Regression analyses were completed (1) to determine the association of age, gender, number of systemic comorbidities, depression, and VA with self-reported visual function and (2) to estimate a visual impairment-related difference for each subscale based on differences in VA. The NEI-VFQ-25 scores in persons with visual impairment. Of the 5287 LALES participants with complete NEI-VFQ-25 data, 6.3% (including 20/40) and 4.2% (excluding 20/40) were visually impaired. In the visually impaired participants, the NEI-VFQ-25 subscale scores ranged from 46.2 (General Health) to 93.8 (Color Vision). In the regression model, only VA, depression, and number of comorbidities were significantly associated with all subscale scores (R(2) ranged from 0.09 for Ocular Pain to 0.33 for the composite score). For 9 of 11 subscales, a 5-point change was equivalent to a 1- or 2-line difference in VA. Relationships were similar regardless of the definition of visual impairment. In this population-based study of Latinos, the NEI-VFQ-25 was sensitive to differences in VA. A 5-point difference on the NEI-VFQ-25 seems to be a minimal criterion for a visual impairment-related difference. Self-reported visual function is essentially unchanged if the definition of visual impairment includes or excludes a VA of 20/40.

Problem solving of student with visual impairment related to mathematical literacy problem

NASA Astrophysics Data System (ADS)

Pratama, A. R.; Saputro, D. R. S.; Riyadi

2018-04-01

The student with visual impairment, total blind category depends on the sense of touch and hearing in obtaining information. In fact, the two senses can receive information less than 20%. Thus, students with visual impairment of the total blind categories in the learning process must have difficulty, including learning mathematics. This study aims to describe the problem-solving process of the student with visual impairment, total blind category on mathematical literacy issues based on Polya phase. This research using test method similar problems mathematical literacy in PISA and in-depth interviews. The subject of this study was a student with visual impairment, total blind category. Based on the result of the research, problem-solving related to mathematical literacy based on Polya phase is quite good. In the phase of understanding the problem, the student read about twice by brushing the text and assisted with information through hearing three times. The student with visual impairment in problem-solving based on the Polya phase, devising a plan by summoning knowledge and experience gained previously. At the phase of carrying out the plan, students with visual impairment implement the plan in accordance with pre-made. In the looking back phase, students with visual impairment need to check the answers three times but have not been able to find a way.

Prevalence and causes of visual impairment and rate of wearing spectacles in schools for children of migrant workers in Shanghai, China.

PubMed

He, Jiangnan; Lu, Lina; Zou, Haidong; He, Xiangui; Li, Qiangqiang; Wang, Weijie; Zhu, Jianfeng

2014-12-22

To assess the prevalence of visual impairment and rate of wearing spectacles in schools for children of migrant workers in Shanghai, China. Children from grade 1 to 5 in schools for children of migrant workers were randomly chosen for ocular examinations. All children were screened for uncorrected visual acuity and presenting visual acuity. After screening, the children whose uncorrected visual acuity was 20/40 or less received ocular motility evaluation, cycloplegic refraction/non-cycloplegic refraction, and external eye, anterior segment, media, and fundus examinations. A total of 9673 children were enumerated and 9512 (98.34%) participated in this study. The prevalence of uncorrected, presenting, and best-corrected visual acuity of 20/40 or worse in the better eye were 13.33%, 11.26%, and 0.63%, respectively. The rate of wearing spectacles of the children with visual impairment in one or both eyes was 15.50%. Of these, 26.05% were wearing spectacles with inaccurate prescriptions. Refractive error was a major cause of visual impairment, accounting for 89.48% of all the visual impairment causes. Other causes of visual impairment included amblyopia accounting for 10.12%; congenital cataract, 0.1%; congenital nystagmus, 0.1%; ocular prosthesis, 0.1%; macular degeneration, 0.05%; and opaque cornea, 0.05%. This is the first study of the prevalence and causes of visual impairment in schools for children of migrant workers in Shanghai, China. The visual impairment rate in schools for children of migrant workers in suburbs of Shanghai in the best eye before vision correction was lower than those of urban children in mainstream schools in Guangzhou in 2012, and higher than students in rural of Beijing in 1998 and in suburb of Chongqing in 2007. The refractive error was the principal cause of the visual impairment of the children of migrant workers. The rate of wearing spectacles was low and the percentage of inaccurate prescriptions, among those who wore spectacles, was high. Uncorrected refractive error was a significant cause of visual impairment in migrant children.

Emotion-induced trade-offs in spatiotemporal vision.

PubMed

Bocanegra, Bruno R; Zeelenberg, René

2011-05-01

It is generally assumed that emotion facilitates human vision in order to promote adaptive responses to a potential threat in the environment. Surprisingly, we recently found that emotion in some cases impairs the perception of elementary visual features (Bocanegra & Zeelenberg, 2009b). Here, we demonstrate that emotion improves fast temporal vision at the expense of fine-grained spatial vision. We tested participants' threshold resolution with Landolt circles containing a small spatial or brief temporal discontinuity. The prior presentation of a fearful face cue, compared with a neutral face cue, impaired spatial resolution but improved temporal resolution. In addition, we show that these benefits and deficits were triggered selectively by the global configural properties of the faces, which were transmitted only through low spatial frequencies. Critically, the common locus of these opposite effects suggests a trade-off between magno- and parvocellular-type visual channels, which contradicts the common assumption that emotion invariably improves vision. We show that, rather than being a general "boost" for all visual features, affective neural circuits sacrifice the slower processing of small details for a coarser but faster visual signal.

Support for distinct subcomponents of spatial working memory: a double dissociation between spatial-simultaneous and spatial-sequential performance in unilateral neglect.

PubMed

Wansard, Murielle; Bartolomeo, Paolo; Bastin, Christine; Segovia, Fermín; Gillet, Sophie; Duret, Christophe; Meulemans, Thierry

2015-01-01

Over the last decade, many studies have demonstrated that visuospatial working memory (VSWM) can be divided into separate subsystems dedicated to the retention of visual patterns and their serial order. Impaired VSWM has been suggested to exacerbate left visual neglect in right-brain-damaged individuals. The aim of this study was to investigate the segregation between spatial-sequential and spatial-simultaneous working memory in individuals with neglect. We demonstrated that patterns of results on these VSWM tasks can be dissociated. Spatial-simultaneous and sequential aspects of VSWM can be selectively impaired in unilateral neglect. Our results support the hypothesis of multiple VSWM subsystems, which should be taken into account to better understand neglect-related deficits.

Self-concept, self-esteem, personality traits and psychopathological symptoms in adolescents with and without visual impairment.

PubMed

Garaigordobil, Maite; Bernarás, Elena

2009-05-01

The purpose of this study was to analyze self-concept, self-esteem, and other personality traits and psychopathological symptoms in subjects with and without visual impairment. The sample was made up of 90 participants aged 12 to 17: 61 with no impairment and 29 with visual impairment. The ANOVA showed that there were no significant differences in self-concept and self-esteem in the samples, but the visually impaired adolescents scored significantly higher in various psychopathological symptoms as well as in their capacity for kind behavior. The ANOVA revealed no gender differences in any variables in adolescents without visual impairment. However, women with visual impairment scored lower in self-esteem and higher in various psychopathological symptoms. Pearson coefficients revealed negative relations between self-concept/self-esteem and all the psychopathological symptoms, and neuroticism, as well as a positive relation with extraversion. Low psychoticism, high extraversion, and low hostility were identified as predictors of high self-concept.

Demographic Characteristics and Impairments of Louisiana Students with Usher's Syndrome.

ERIC Educational Resources Information Center

Brown, S. C.

1987-01-01

Of 51 Louisiana students with Usher's Syndrome (a genetic condition characterized by hearing loss and progressive blindness), 71 percent manifested visual impairment and hearing loss, 9 percent had neither, 10 percent had visual impairments but a less-than-profound hearing loss, and 10 percent had profound hearing loss and no visual impairment.…

Coping with a Visual Impairment through Self-Investigation.

ERIC Educational Resources Information Center

van Huijgevoort, Toos

2002-01-01

This article describes how the self-confrontation method (SCM) can help people cope with visual impairment. The actual impact of the impairment can be studied by establishing how being visually impaired is expressed in self-narratives. The different phases of SCM are explained and two case studies are presented. (Contains references.) (Author/CR)

Visual impairment and the incidence of falls and fractures among older people: longitudinal findings from the Blue Mountains Eye Study.

PubMed

Hong, Thomas; Mitchell, Paul; Burlutsky, George; Samarawickrama, Chameen; Wang, Jie Jin

2014-11-04

We assessed the impact of visual impairment on the incidence of falls and fractures in older persons. Of 3654 baseline participants, 2334, 1952, and 1149 were re-examined after 5, 10, and 15 years. Presenting visual acuity (VA) was measured at each examination. Bilateral and unilateral visual impairment was defined as VA worse than 20/40 in the better and worse eye, respectively. Incident visual impairment was defined in eyes with VA 20/40 or better at baseline, which subsequently developed visual impairment. Incidence of falls was assessed over the 12 months before each visit, whereas incidence of fractures was assessed over the 5 years between two visits. Discrete logistic-regression models with time-dependent variables were used to assess associations between visual impairment and subsequent falls and fractures after adjusting for potential confounding variables. The proportions of participants reporting ≥2 falls ranged between 10% and 14%, and proportions reporting fractures ranged between 12% and 21%, across the three follow-up visits. Participants with incident visual impairment were more likely to report ≥2 falls in 5 years, OR (odds ratio) 1.46, 95% confidence interval (CI) 1.04 to 2.04 (bilateral), and OR 1.22, 95% CI 0.98 to 1.51 (unilateral). Compared to participants with normal vision, those with incident unilateral visual impairment had a higher incidence of fractures over 5 years (OR, 1.27; 95% CI, 0.98-1.51). No increased incidence of falls or fractures was evident after 5+ years among participants with visual impairment. In this older cohort, recent development of visual impairment was associated with increased likelihood of subsequent falls and fractures in the next 5 years, independent of other confounding variables. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Visual impairment and spectacle coverage rate in Baoshan district, China: population-based study

PubMed Central

2013-01-01

Background To investigate the prevalence and risk factors of visual impairment associated with refractive error and the unmet need for spectacles in a special suburban senior population in Baoshan District of Shanghai, one of several rural areas undergoing a transition from rural to urban area, where data of visual impairment are limited. Methods The study was a population based survey of 4545 Chinese aged (age: >60 years or older ) at Baoshan, Shanghai, in 2009. One copy of questionnaire was completed for each subject. Examinations included a standardized refraction and measurement of presenting and best corrected visual acuity (BCVA) as well as tonometry, slit lamp biomicroscopy, and fundus photography. Results The prevalence of mild (6/12 to 6/18), moderate (6/18 to 6/60) and severe visual impairment was 12.59%, 8.38% and 0.44%, respectively, and 5.26%, 3.06% and 0.09% with refractive correction. Visual impairment was associated with age, gender, education and career, but not insurance . The prevalence of correctable visual impairment was 5.81% (using 6/18 cutoff) and 13.18% (using 6/12 cutoff). Senior people and women were significantly at a higher risk of correctable visual impairment, while the well-educated on the contrary. The prevalence of undercorrected refractive error (improves by 2 or more lines with refraction) was 24.84%, and the proportion with undercorrected refractive error for mild, moderate , severe and no visual impairment was 61.54%, 67.98%, 60.00% and 14.10%, respectively. The spectacle coverage rate was 44.12%. Greater unmet need for spectacles was observed among elderly people, females, non-peasant, and subjects with less education and astigmatism only. Conclusions High prevalence of visual impairment, visual impairment alleviated by refractive correction, and low spectacle coverage existed among the senior population in Baoshan District of Shanghai. Education for the public of the importance of regular examination and appropriate and accessible refraction service might be helpful to solve the problem. PMID:23566106

Visual Impairment

MedlinePlus

... site Sitio para adolescentes Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Visual Impairment KidsHealth / For Teens / Visual Impairment What's in ...

Teaching Technology Education to Visually Impaired Students.

ERIC Educational Resources Information Center

Mann, Rene

1987-01-01

Discusses various types of visual impairments and how the learning environment can be adapted to limit their effect. Presents suggestions for adapting industrial arts laboratory activities to maintain safety standards while allowing the visually impaired to participate. (CH)

Assisting the visually impaired to deal with telephone interview jobs using information and commutation technology.

PubMed

Yeh, Fung-Huei; Yang, Chung-Chieh

2014-12-01

This study proposed a new information and commutation technology assisted blind telephone interview (ICT-ABTI) system to help visually impaired people to do telephone interview jobs as normal sighted people and create more diverse employment opportunities for them. The study also used an ABAB design to assess the system with seven visually impaired people. As the results, they can accomplish 3070 effective telephone interviews per month independently. The results also show that working performance of the visually impaired can be improved effectively with appropriate design of operation working flow and accessible software. The visually impaired become productive, lucrative, and self-sufficient by using ICT-ABTI system to do telephone interview jobs. The results were also shared through the APEC Digital Opportunity Center platform to help visually impaired in Philippines, Malaysia and China. Copyright © 2014 Elsevier Ltd. All rights reserved.

Loneliness and self-management abilities in the visually impaired elderly.

PubMed

Alma, Manna A; Van der Mei, Sijrike F; Feitsma, W Nathalie; Groothoff, Johan W; Van Tilburg, Theo G; Suurmeijer, Theo P B M

2011-08-01

To describe the degree of loneliness among the visually impaired elderly and to make a comparison with a matched reference group of the normally sighted elderly. In addition, we examined self-management abilities (SMAs) as determinants of loneliness among the visually impaired elderly. In a cross-sectional study, 173 visually impaired elderly persons completed telephone interviews. Loneliness and SMAs were assessed with the Loneliness Scale of De Jong Gierveld and the SMAS-30, respectively. The prevalence of loneliness among the visually impaired elderly was higher compared with the reference group (50% vs. 29%; p < .001). Multivariate hierarchical regression analysis showed that the SMA self-efficacy, partner status, and self-esteem were determinants of loneliness. Severity and duration of visual impairment had no effect on loneliness. The relationship between SMAs (i.e., self-efficacy) and loneliness is promising, as SMAs can be learned through training. Consequently, self-management training may reduce feelings of loneliness.

Selective scene perception deficits in a case of topographical disorientation.

PubMed

Robin, Jessica; Lowe, Matthew X; Pishdadian, Sara; Rivest, Josée; Cant, Jonathan S; Moscovitch, Morris

2017-07-01

Topographical disorientation (TD) is a neuropsychological condition characterized by an inability to find one's way, even in familiar environments. One common contributing cause of TD is landmark agnosia, a visual recognition impairment specific to scenes and landmarks. Although many cases of TD with landmark agnosia have been documented, little is known about the perceptual mechanisms which lead to selective deficits in recognizing scenes. In the present study, we test LH, a man who exhibits TD and landmark agnosia, on measures of scene perception that require selectively attending to either the configural or surface properties of a scene. Compared to healthy controls, LH demonstrates perceptual impairments when attending to the configuration of a scene, but not when attending to its surface properties, such as the pattern of the walls or whether the ground is sand or grass. In contrast, when focusing on objects instead of scenes, LH demonstrates intact perception of both geometric and surface properties. This study demonstrates that in a case of TD and landmark agnosia, the perceptual impairments are selective to the layout of scenes, providing insight into the mechanism of landmark agnosia and scene-selective perceptual processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Childhood visual impairment: normal and abnormal visual function in the context of developmental disability.

PubMed

Nyong'o, Omondi L; Del Monte, Monte A

2008-12-01

Abnormal or failed development of vision in children may give rise to varying degrees of visual impairment and disability. Disease and organ-specific mechanisms by which visual impairments arise are presented. The presentation of these mechanisms, along with an explanation of established pathologic processes and correlative up-to-date clinical and social research in the field of pediatrics, ophthalmology, and rehabilitation medicine are discussed. The goal of this article is to enhance the practitioner's recognition and care for children with developmental disability associated with visual impairment.

Prevalence of visual impairment and outcomes of cataract surgery in Chaonan, South China

PubMed Central

Zhang, Xiujuan; Li, Emmy Y.; Leung, Christopher Kai-Shun; Musch, David C.; Tang, Xin; Zheng, Chongren; He, Mingguang; Chang, David F.

2017-01-01

Purpose To estimate the prevalence and causes of blindness and visual impairment (VI), and report the outcomes of cataract surgery in Chaonan Region, Guangdong Province, southern China Design Cross-sectional population-based survey Participants A total of 3484 participants including 1397 men (40.1%) and 2087 women (59.9%) aged ≥50 years were examined (94.2% response rate). Method A two-stage cluster sampling procedure was used to select 3700 participants aged ≥50 years from 74 clusters of Chaonan Region. Participants were examined according to the Rapid Assessment of Avoidable Blindness (RAAB) method. Blindness and visual impairment (VI) were defined by the World Health Organization criteria. Participants with visual acuity (VA) < 6/18 in either eye were examined by ophthalmologists. The primary causes of blindness and VI were reported with reference to the participant’s better eye. Main outcome measures Prevalence and main causes of blindness, severe visual impairment (SVI), VI and the outcomes of cataract surgery Results The standardized prevalence rates of blindness, SVI, and VI were 2.4% (95% confidence interval [CI], 1.9–2.9%), 1.0% (95% CI, 0.7–1.4%), and 6.4% (95% CI, 5.6%– 7.1%), respectively. The principal cause of blindness and SVI was cataract, accounting for 67.1% and 67.6% respectively, and the principal cause of VI was refractive error (46.9%). One hundred and fifty five out of 3484 (4.4%) people (211 eyes) had cataract surgery. Of the 211 eyes that had cataract surgery, 96.7% were pseudophakic. 67.2% of the 211 operated eyes had a presenting visual acuity (PVA) of 6/18 or better. Conclusions The prevalence of blindness, SVI, and VI was high among rural residents in Chaonan. Cataract remained the leading cause of avoidable blindness. Outcomes of cataract surgery performed in rural private clinics were suboptimal. Quality-control initiatives such as hands-on training program should be introduced to improve cataract surgery outcomes. PMID:28797099

Social Determinants and Their Impact on Visual Impairment in Southern Mexico.

PubMed

Jimenez-Corona, Aida; Jimenez-Corona, Maria E; Ponce-de-Leon, Samuel; Chavez-Rodriguez, Mariela; Graue-Hernandez, Enrique O

2015-01-01

Visual impairment in disadvantaged populations in Mexico has been scarcely reported. We compared the prevalence of visual impairment and its associated risk factors in populations in rural compared to urban areas of the Mexican southern state of Chiapas. In a population-based study, the prevalence of visual impairment in rural and urban areas of Comitan, Chiapas, was estimated. All eligible individuals aged ≥20 years living in rural areas were invited to participate; persons from urban areas were chosen randomly. Individuals were considered of indigenous (IND) origin either by self-report or if they spoke an IND language. Visual acuity (VA) and pinhole VA were measured using a tumbling E chart. VA was defined as normal (better than or equal to 20/60), moderate impairment (worse than 20/60 but better than or equal to 20/200), severe impairment (worse than 20/200 but better than or equal to 20/400), or blindness (worse than 20/400). Data on VA were obtained from 969 persons (610 rural, 359 urban) whose mean age was 43.3 years (standard deviation 15.6 years). Prevalence of moderate visual impairment was higher in rural (10.2%, 95% confidence interval, CI, 7.2-14.2%) than urban (3.9%, 95% CI 1.9-7.9%) areas (p < 0.001). Persons with moderate visual impairment were older and less educated (both p < 0.001). Rural individuals aged 50 years and older had 4.4 times (95% CI 1.8-11.3, p = 0.002) the likelihood of having moderate visual impairment compared with urban persons. Unfavorable socioeconomic conditions were associated with higher prevalence of moderate visual impairment in rural compared with urban populations in Mexico.

Perceptions of the Visually Impaired toward Pursuing Geography Courses and Majors in Higher Education

ERIC Educational Resources Information Center

Murr, Christopher D.; Blanchard, R. Denise

2011-01-01

Advances in classroom technology have lowered barriers for the visually impaired to study geography, yet few participate. Employing stereotype threat theory, we examined whether beliefs held by the visually impaired affect perceptions toward completing courses and majors in visually oriented disciplines. A test group received a low-level threat…

Defective imitation of finger configurations in patients with damage in the right or left hemispheres: An integration disorder of visual and somatosensory information?

PubMed

Okita, Manabu; Yukihiro, Takashi; Miyamoto, Kenzo; Morioka, Shu; Kaba, Hideto

2017-04-01

To explore the mechanism underlying the imitation of finger gestures, we devised a simple imitation task in which the patients were instructed to replicate finger configurations in two conditions: one in which they could see their hand (visual feedback: VF) and one in which they could not see their hand (non-visual feedback: NVF). Patients with left brain damage (LBD) or right brain damage (RBD), respectively, were categorized into two groups based on their scores on the imitation task in the NVF condition: the impaired imitation groups (I-LBD and I-RBD) who failed two or more of the five patterns and the control groups (C-LBD and C-RBD) who made one or no errors. We also measured the movement-production times for imitation. The I-RBD group performed significantly worse than the C-RBD group even in the VF condition. In contrast, the I-LBD group was selectively impaired in the NVF condition. The I-LBD group performed the imitations at a significantly slower rate than the C-LBD group in both the VF and NVF conditions. These results suggest that impaired imitation in patients with LBD is partly due to an abnormal integration of visual and somatosensory information based on the task specificity of the NVF condition. Copyright © 2017 Elsevier Inc. All rights reserved.

Eye Movement Analysis and Cognitive Assessment. The Use of Comparative Visual Search Tasks in a Non-immersive VR Application.

PubMed

Rosa, Pedro J; Gamito, Pedro; Oliveira, Jorge; Morais, Diogo; Pavlovic, Matthew; Smyth, Olivia; Maia, Inês; Gomes, Tiago

2017-03-23

An adequate behavioral response depends on attentional and mnesic processes. When these basic cognitive functions are impaired, the use of non-immersive Virtual Reality Applications (VRAs) can be a reliable technique for assessing the level of impairment. However, most non-immersive VRAs use indirect measures to make inferences about visual attention and mnesic processes (e.g., time to task completion, error rate). To examine whether the eye movement analysis through eye tracking (ET) can be a reliable method to probe more effectively where and how attention is deployed and how it is linked with visual working memory during comparative visual search tasks (CVSTs) in non-immersive VRAs. The eye movements of 50 healthy participants were continuously recorded while CVSTs, selected from a set of cognitive tasks in the Systemic Lisbon Battery (SLB). Then a VRA designed to assess of cognitive impairments were randomly presented. The total fixation duration, the number of visits in the areas of interest and in the interstimulus space, along with the total execution time was significantly different as a function of the Mini Mental State Examination (MMSE) scores. The present study demonstrates that CVSTs in SLB, when combined with ET, can be a reliable and unobtrusive method for assessing cognitive abilities in healthy individuals, opening it to potential use in clinical samples.

Attention-deficit/hyperactivity disorder and attention impairment in children with benign childhood epilepsy with centrotemporal spikes.

PubMed

Kim, Eun-Hee; Yum, Mi-Sun; Kim, Hyo-Won; Ko, Tae-Sung

2014-08-01

Attention-deficit/hyperactivity disorder (ADHD) is a common comorbidity in children with epilepsy and has a negative impact on behavior and learning. The purposes of this study were to quantify the prevalence of ADHD in benign childhood epilepsy with centrotemporal spikes (BCECTS) and to identify clinical factors that affect ADHD or attention impairment in patients with BCECTS. The medical records of 74 children (44 males) with neuropsychological examination from a total of 198 children diagnosed with BCECTS at Asan Medical Center were retrospectively reviewed. Electroclinical factors were compared across patients with ADHD and those without ADHD. Mean T-scores of the continuous performance test were compared across patients grouped according to various epilepsy characteristics. Forty-eight (64.9%) patients had ADHD. A history of febrile convulsion was more common in patients with ADHD than in patients without ADHD (p=0.049). Bilateral centrotemporal spikes on electroencephalogram were more common in patients receiving ADHD medication than in patients with untreated ADHD (p=0.004). Male patients, patients with frequent seizures prior to diagnosis, and patients with a high spike index (≥40/min) on sleep EEG at diagnosis had significantly lower visual selective attention (p<0.05). Children with BCECTS had a high prevalence of ADHD, and frequent seizures or interictal epileptiform abnormalities were closely related to impairment of visual selective attention in children with BCECTS, indicating the need for ADHD or attention impairment screening in children with BCECTS. Copyright © 2014 Elsevier Inc. All rights reserved.

Key factors for the bicycle use of visually impaired people: a Delphi study.

PubMed

Jelijs, Bart; Heutink, Joost; de Waard, Dick; Brookhuis, Karel A; Melis-Dankers, Bart J M

2018-06-12

This study aims to identify the most important factors that influence the independent bicycle use of visually impaired people in the Netherlands. Both visually impaired people and professionals participated in a two-round online Delphi study (n = 42). In Round 1 the participants identified the factors which they ranked by relevance in Round 2. The participants prioritised environmental factors related to the traffic situation, the characteristics of the infrastructure, and weather and light conditions (Kendall's W = 0.66). They indicated that the most influencing personal factors are related to personality, traffic experience, and personal background (W = 0.58). Glaucoma was ranked as the most relevant ophthalmic condition (W = 0.74), while glare was regarded as the most important factor with respect to the visual functions (W = 0.78). The factors provided by this study can be used to optimise the independent cycling mobility of visually impaired people. More research is needed to investigate, both, how and to what extent the mentioned factors influence the cycling behaviour. Implications for rehabilitation The results of this study can be used to set priorities during the rehabilitation and training of visually impaired people who wish to cycle independently. Visually impaired cyclists may compensate for the consequences of their visual impairments by taking alternative routes that suit their individual abilities and limitations. Since gaining and maintaining self-confidence is important for independent cycling with a visual impairment, practitioners such as mobility trainers should not only focus on cycling-related skills and abilities, but also aim to improve the self-confidence of visually impaired people who wish to cycle.

Visual impairment among 10-14-year school children in Puducherry: A cross-sectional study.

PubMed

Vishnuprasad, R; Bazroy, Joy; Madhanraj, K; Prashanth, Hannah Ranjee; Singh, Zile; Samuel, Abel K; Muthukumar, T

2017-01-01

According to the 2010 estimates by the World Health Organization, nearly 285 million (4.24% of total population) people of all ages worldwide are visually impaired. Almost 18.9 million children under 15 years of age are visually impaired globally. In developing countries, 7%-31% of childhood blindness and visual impairment is avoidable. The study was conducted as a cross-sectional study among 1884 school students in Puducherry, in the age group of 10-14 years. A child with presenting maximum vision ≤6/12 Snellen equivalent in the better eye is considered visually impaired. Data were entered in Microsoft Excel 2013 and analyzed using the statistical software SPSS version 21.0. Chi-square test was applied for testing difference in proportion and a P < 0.05 was considered statistically significant. The overall prevalence of visual impairment (vision ≤6/12) among the study participants was 6.37% (95% confidence interval = 5.27-7.47). The prevalence of visual impairment increased with age and it was found to be high among male students (6.6%) when compared to female students (6%). Presenting vision of 6/6 was observed in 79.8% of the children while with pinhole correction, the proportion increased to 94.6%. The prevalence of visual impairment in our study population was found to be 6.37% and the prevalence was even higher among children who belonged to schools of urban region or private schools. Children with a positive family history of spectacle use were more likely to have visual impairment.

Perceptual learning in children with visual impairment improves near visual acuity.

PubMed

Huurneman, Bianca; Boonstra, F Nienke; Cox, Ralf F A; van Rens, Ger; Cillessen, Antonius H N

2013-09-17

This study investigated whether visual perceptual learning can improve near visual acuity and reduce foveal crowding effects in four- to nine-year-old children with visual impairment. Participants were 45 children with visual impairment and 29 children with normal vision. Children with visual impairment were divided into three groups: a magnifier group (n = 12), a crowded perceptual learning group (n = 18), and an uncrowded perceptual learning group (n = 15). Children with normal vision also were divided in three groups, but were measured only at baseline. Dependent variables were single near visual acuity (NVA), crowded NVA, LH line 50% crowding NVA, number of trials, accuracy, performance time, amount of small errors, and amount of large errors. Children with visual impairment trained during six weeks, two times per week, for 30 minutes (12 training sessions). After training, children showed significant improvement of NVA in addition to specific improvements on the training task. The crowded perceptual learning group showed the largest acuity improvements (1.7 logMAR lines on the crowded chart, P < 0.001). Only the children in the crowded perceptual learning group showed improvements on all NVA charts. Children with visual impairment benefit from perceptual training. While task-specific improvements were observed in all training groups, transfer to crowded NVA was largest in the crowded perceptual learning group. To our knowledge, this is the first study to provide evidence for the improvement of NVA by perceptual learning in children with visual impairment. (http://www.trialregister.nl number, NTR2537.).

[Frequency and causes of blindness and visual impairment in schools for the blind in Yaoundé (Cameroon)].

PubMed

Noche, Christelle Domngang; Bella, Assumpta Lucienne

2010-01-01

To determine the causes of blindness and visual impairment in students attending schools for the blind in Yaounde (Cameroon) and to estimate their frequencies. This study examined all 56 students at three schools for the blind in Yaoundé from September 15 through October 15, 2006. We collected data about their age, sex, medical and surgical history. Visual acuity was measured to determine their vision status according to the World Health Organization categories for blindness and visual impairment. All subjects underwent an ocular examination. Epi Info 3.5.1. was used for the statistical analysis of age, sex, visual acuity, causes of blindness and visual impairment, and etiologies. Fifty six people were examined: 37 men (66.1%) and 19 women (33.9%). Their mean age was 21.57 ± 10.53 years (min-max: 5-49), and 48.2% were in the 10-19 years age group (n = 27). In all, 87.5% were blind, 7.14% severely visually impaired, and 1.78% moderately visually impaired. The main causes of blindness and visual impairment in our sample were corneal disease (32.14%), optic nerve lesions (26.78%), cataract and its surgical complications (19.64%), retinal disorders (10.71%), glaucoma (8.92%, and malformations of the eyeball (1.78%). Their etiologies included congenital cataracts (19.64%), meningitis/fever (8.92%), glaucoma (7.14%), measles (5.35%), ocular trauma (5.35%), albinism (3.57%), Lyell syndrome (1.8%), and alcohol ingestion (1.8%). Etiology was unknown in 46.42%. Fifty per cent of these causes of blindness and visual impairment were treatable and/or preventable. Corneal lesions were the main cause of blindness and visual impairment in our sample. Fifty per cent of the causes found were treatable and/or preventable. Thus, substantial efforts are required to ensure access to better quality specialist ocular care. Furthermore, local authorities should create more centers specialised in the rehabilitation of the visual handicapped.

Visual impairment and blindness in spanish adults: geographic inequalities are not explained by age or education.

PubMed

Rius, Anna; Artazcoz, Lucía; Guisasola, Laura; Benach, Joan

2014-01-01

The objectives of this study were to examine for the first time the prevalence of visual impairment and blindness among adults in Spain, to explore regional differences, and to assess whether they may vary as a function of sex or be explained by age and individual or regional socioeconomic position. Data were obtained from the 2008 Spanish Survey on Disability, Personal Autonomy, and Dependency Situations, a cross-sectional survey based on a representative sample of the noninstitutionalized population of Spain. The sample was composed of 213 626 participants aged ≥15 years (103 093 men and 110 533 women); 360 were blind (160 men and 200 women), 4048 had near visual impairment (1397 men and 2651 women), and 4034 had distance visual impairment (1445 men and 2589 women). The prevalence of near and distance visual impairment was calculated for each region. Multiple logistic regression models were fitted to calculate odds ratios and 95% confidence intervals. All analyses were stratified by sex. Visual impairment was based on 3 questions aimed at identifying blindness and near and distance visual impairment. The prevalence (percentage) of blindness was 0.17 (men, 0.16; women, 0.18): 1.89 for near visual impairment (men, 1.36; women, 2.40), 1.89 for distance visual impairment (men, 1.40; women, 2.34), and 2.43 for any visual impairment (men, 1.81; women, 3.02). Regional inequalities in the prevalence of visual impairment were observed, correlated with regional income, and the prevalence was consistently higher among women than men. The magnitude of the inequalities remained after adjusting for age and educational level, and a north-to-south pattern of increasing prevalence was observed. Regional and sex inequalities in the prevalence of visual impairment and blindness were observed in Spain, with a north-to-south gradient of increasing prevalence that was not explained by age or individual educational level but was correlated with regional level of economic development. Factors that could be prioritized for future policies and research include differential regional economic development, rural environment, quality of eye care services, diabetes, ultraviolet light exposure, or gender inequalities in diagnostic and therapeutic health care. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Impaired response selection in schizophrenia: Evidence from the P3 wave and the lateralized readiness potential

PubMed Central

Luck, Steven J.; Kappenman, Emily S.; Fuller, Rebecca L.; Robinson, Benjamin; Summerfelt, Ann; Gold, James M.

2008-01-01

Reaction times (RTs) are substantially prolonged in schizophrenia patients, but the latency of the P3 component is not. This suggests that the RT slowing arises from impairments in a late stage of processing. To test this hypothesis, 20 schizophrenia patients and 20 control subjects were tested in a visual oddball paradigm that was modified to allow measurement of the lateralized readiness potential (LRP), an index of stimulus-response translation processes. Difference waves were used to isolate the LRP and the P3 wave. Patients and control subjects exhibited virtually identical P3 difference waves, whereas the LRP difference wave was reduced in amplitude and delayed in latency in the patients. These results indicate that, at least in simple tasks, the delayed RTs observed in schizophrenia are primarily a consequence of impairments in the response selection and preparation processes that follow perception and categorization. PMID:19386044

Reduced health-related quality of life among Japanese college students with visual impairment.

PubMed

Masaki, Iguchi

2015-01-01

Although previous studies have shown detrimental effects of visual impairment on health-related quality of life (HRQOL), they were primarily conducted on elderly individuals with visual impairment. The objective of this cross-sectional study was to investigate if HRQOL is impaired in young college students with visual impairment and to explore the relationships between HRQOL and other factors. It was hypothesized that visual impairment is not influential enough to lower the HRQOL of young people due to their better physical fitness and more flexible mentality. A total of 21 college students (mean age = 25 years old) with varying degrees of visual impairment completed the short form (SF)-36 health survey and questionnaires on daily physical activities. Subjects were grouped depending on the type of visual impairment: blind (n = 11) or severely impaired (n = 10). In addition, grip strength and single-leg standing balance were assessed. No between-group differences were found in the SF-36 scores. However, compared to the general Japanese standards (50.0 ± 10.0), the Vitality scores of the blind group were lower (41.9 ± 7.2, p = 0.004) and the Physical Function scores of the severely impaired group were higher (55.3 ± 2.4, p = 0.001). In addition, a negative correlation was found between standing balance (variability of foot center of pressure) and the Physical Component Summary score of the SF-36 (r(2) = 0.35, p = 0.005). These findings suggest that even among young people severe visual impairment leads to reductions in some components of HRQOL.

Smart-system of distance learning of visually impaired people based on approaches of artificial intelligence

NASA Astrophysics Data System (ADS)

Samigulina, Galina A.; Shayakhmetova, Assem S.

2016-11-01

Research objective is the creation of intellectual innovative technology and information Smart-system of distance learning for visually impaired people. The organization of the available environment for receiving quality education for visually impaired people, their social adaptation in society are important and topical issues of modern education.The proposed Smart-system of distance learning for visually impaired people can significantly improve the efficiency and quality of education of this category of people. The scientific novelty of proposed Smart-system is using intelligent and statistical methods of processing multi-dimensional data, and taking into account psycho-physiological characteristics of perception and awareness learning information by visually impaired people.

Stroke survivors' views and experiences on impact of visual impairment.

PubMed

Rowe, Fiona J

2017-09-01

We sought to determine stroke survivors' views on impact of stroke-related visual impairment to quality of life. Stroke survivors with visual impairment, more than 1 year post stroke onset, were recruited. Semistructured biographical narrative interviews were audio-recorded and transcribed verbatim. A thematic approach to analysis of the qualitative data was adopted. Transcripts were systematically coded using NVivo10 software. Thirty-five stroke survivors were interviewed across the UK: 16 females, 19 males; aged 20-75 years at stroke onset. Five qualitative themes emerged: "Formal care," "Symptoms and self," "Adaptations," "Daily life," and "Information." Where visual problems existed, they were often not immediately recognized as part of the stroke syndrome and attributed to other causes such as migraine. Many participants did not receive early vision assessment or treatment for their visual problems. Visual problems included visual field loss, double vision, and perceptual problems. Impact of visual problems included loss in confidence, being a burden to others, increased collisions/accidents, and fear of falling. They made many self-identified adaptations to compensate for visual problems: magnifiers, large print, increased lighting, use of white sticks. There was a consistent lack of support and provision of information about visual problems. Poststroke visual impairment causes considerable impact to daily life which could be substantially improved by simple measures including early formal visual assessment, management and advice on adaptive strategies and self-management options. Improved education about poststroke visual impairment for the public and clinicians could aid earlier diagnosis of visual impairments.

Visual attention: Linking prefrontal sources to neuronal and behavioral correlates.

PubMed

Clark, Kelsey; Squire, Ryan Fox; Merrikhi, Yaser; Noudoost, Behrad

2015-09-01

Attention is a means of flexibly selecting and enhancing a subset of sensory input based on the current behavioral goals. Numerous signatures of attention have been identified throughout the brain, and now experimenters are seeking to determine which of these signatures are causally related to the behavioral benefits of attention, and the source of these modulations within the brain. Here, we review the neural signatures of attention throughout the brain, their theoretical benefits for visual processing, and their experimental correlations with behavioral performance. We discuss the importance of measuring cue benefits as a way to distinguish between impairments on an attention task, which may instead be visual or motor impairments, and true attentional deficits. We examine evidence for various areas proposed as sources of attentional modulation within the brain, with a focus on the prefrontal cortex. Lastly, we look at studies that aim to link sources of attention to its neuronal signatures elsewhere in the brain. Copyright © 2015. Published by Elsevier Ltd.

Resolution of spatial and temporal visual attention in infants with fragile X syndrome.

PubMed

Farzin, Faraz; Rivera, Susan M; Whitney, David

2011-11-01

Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal-parietal networks of the brain. The goal of the current study was to examine whether reduced resolution of spatial and/or temporal visual attention may underlie perceptual deficits related to fragile X syndrome. Eye tracking was used to psychophysically measure the limits of spatial and temporal attention in infants with fragile X syndrome and age-matched neurotypically developing infants. Results from these experiments revealed that infants with fragile X syndrome experience drastically reduced resolution of temporal attention in a genetic dose-sensitive manner, but have a spatial resolution of attention that is not impaired. Coarse temporal attention could have significant knock-on effects for the development of perceptual, cognitive and motor abilities in individuals with the disorder.

Resolution of spatial and temporal visual attention in infants with fragile X syndrome

PubMed Central

Rivera, Susan M.; Whitney, David

2011-01-01

Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal–parietal networks of the brain. The goal of the current study was to examine whether reduced resolution of spatial and/or temporal visual attention may underlie perceptual deficits related to fragile X syndrome. Eye tracking was used to psychophysically measure the limits of spatial and temporal attention in infants with fragile X syndrome and age-matched neurotypically developing infants. Results from these experiments revealed that infants with fragile X syndrome experience drastically reduced resolution of temporal attention in a genetic dose-sensitive manner, but have a spatial resolution of attention that is not impaired. Coarse temporal attention could have significant knock-on effects for the development of perceptual, cognitive and motor abilities in individuals with the disorder. PMID:22075522

Prevalence of Visual Impairment among 4- to 6-years-old Children in Khon Kaen City Municipality, Thailand.

PubMed

Wongwai, Phanthipha; Anupongongarch, Pacharapan; Suwannaraj, Sirinya; Asawaphureekorn, Somkiat

2016-08-01

To evaluate the prevalence of visual impairment of children aged four to six years in Khon Kaen City Municipality, Thailand. The visual acuity test was performed on 1,286 children in kindergarten schools located in Khon Kaen Municipality. The first test of visual acuity was done by trained teachers and the second test by the pediatric ophthalmologist. The prevalence of visual impairment of both tests was recorded including sensitivity, specificity, likelihood ratio, and predictive value of the test by teachers. The causes of visual impairment were also recorded. There were 39 children with visual impairment from the test by the teacher and 12 children from the test by the ophthalmologist. Myopia is the single cause of visual impairment. Mean spherical equivalence is 1.375 diopters (SD = 0.53). Median spherical equivalence is 1.375 diopters (minimum = 0.5, maximum =4). The detection of visual impairment by trained teachers had a sensitivity of 1.00 (95% CI 0.76-1.00), specificity of 0.98 (95% CI 0.97-0.99), likelihood ratio for a positive test 44.58 (95% CI 30.32-65.54), likelihood ratio for a negative test 0.04 (95% CI 0.003-0.60), positive predictive value of 0.31 (95% CI 0.19-0.47), and negative predictive value of 1.00 (95% CI 0.99-1.00). The prevalence of visual impairment among children aged four to six year old is 0.9%. Trained teachers can be examiners for screening purpose.

Causes of visual impairment in children with low vision.

PubMed

Shah, Mufarriq; Khan, Mirzaman; Khan, Muhammad Tariq; Khan, Mohammad Younas; Saeed, Nasir

2011-02-01

To determine the main causes of visual impairment in children with low vision. To assess the need of spectacles and low vision devices (LVDs) in children and to evaluate visual outcome after using their LVDs for far and near distance. Observational study. Khyber Institute of Ophthalmic Medical Sciences, Peshawar, Pakistan, from June 2006 to December 2007. The clinical record of 270 children with low vision age 4-16 years attending the Low Vision Clinic were included. All those children, aged 4-16 years, who had corrected visual acuity (VA) less than 6/18 in the better eye after medical or surgical treatment, were included in the study. WHO low vision criteria were used to classify into visually impaired, severe visually impaired and blind. Results were described as percentage frequencies. One hundred and eighty nine (70%) were males and 81 (30%) were females. The male to female ratio was 2.3:1. The main causes of visual impairment included nystagmus (15%), Stargardt's disease (14%), maculopathies (13%), myopic macular degeneration (11%) and oculocutaneous albinism (7%). The percentages of visually impaired, severe visually impaired and blind were 33.8%, 27.2% and 39.0% respectively. Spectacles were prescribed to 146 patients and telescopes were prescribed to 75 patients. Spectacles and telescope both were prescribed to 179 patients while Ocutech telescope was prescribed to 4 patients. Retinal diseases nystagmus and macular conditions were mainly responsible for low vision in children. Visually impaired children especially with hereditary/congenital ocular anomalies benefit from refraction and low vision services which facilitate vision enhancement and inclusive education.

Crowding in central vision in normally sighted and visually impaired [corrected] children aged 4 to 8 years: the influence of age and test design.

PubMed

Huurneman, Bianca; Boonstra, F Nienke; Cillessen, Antonius H N; van Rens, Ger; Cox, Ralf F A

2012-06-01

To investigate crowding ratios in children with a visual impairment due to ocular disease (n = 58) and normally sighted children (n = 75) aged 4 to 8 years using several variants of two clinically available tests with different optotype spacing (fixed or proportional to the optotype size). Crowding ratios, calculated by dividing the single acuity by the linear acuity, were measured binocularly with the C-test and the LH line chart. Ratios >1.00 indicate crowding. The charts with fixed spacing revealed significantly higher crowding ratios for visually impaired children than normally sighted children (both for measurements at 40 cm and 5 m). The age-related reduction of the crowding ratios seen in normally sighted children when tested with near-vision charts with fixed spacing was not present in the visually impaired group. Visually impaired children with nystagmus showed higher crowding ratios than visually impaired children without nystagmus. The chart with proportional intersymbol spacing (ISS) did not reveal differences between the normally sighted and visually impaired children; nor did it show group, age, or nystagmus effects. Visually impaired children showed higher crowding ratios than normally sighted children when measured with charts with fixed ISS. This study illustrates that test design and target/flanker interference as a manifestation of crowding are critical issues to bear in mind when assessing crowding ratios in children.

Preterm-associated visual impairment and estimates of retinopathy of prematurity at regional and global levels for 2010

PubMed Central

Blencowe, Hannah; Lawn, Joy E.; Vazquez, Thomas; Fielder, Alistair; Gilbert, Clare

2013-01-01

Background: Retinopathy of prematurity (ROP) is a leading cause of potentially avoidable childhood blindness worldwide. We estimated ROP burden at the global and regional levels to inform screening and treatment programs, research, and data priorities. Methods: Systematic reviews and meta-analyses were undertaken to estimate the risk of ROP and subsequent visual impairment for surviving preterm babies by level of neonatal care, access to ROP screening, and treatment. A compartmental model was used to estimate ROP cases and numbers of visually impaired survivors. Results: In 2010, an estimated 184,700 (uncertainty range: 169,600–214,500) preterm babies developed any stage of ROP, 20,000 (15,500–27,200) of whom became blind or severely visually impaired from ROP, and a further 12,300 (8,300–18,400) developed mild/moderate visual impairment. Sixty-five percent of those visually impaired from ROP were born in middle-income regions; 6.2% (4.3–8.9%) of all ROP visually impaired infants were born at >32-wk gestation. Visual impairment from other conditions associated with preterm birth will affect larger numbers of survivors. Conclusion: Improved care, including oxygen delivery and monitoring, for preterm babies in all facility settings would reduce the number of babies affected with ROP. Improved data tracking and coverage of locally adapted screening/treatment programs are urgently required. PMID:24366462

Visual impairment, coping strategies and impact on daily life: a qualitative study among working-age UK ex-service personnel.

PubMed

Stevelink, Sharon A M; Malcolm, Estelle M; Fear, Nicola T

2015-11-12

Sustaining a visual impairment may have a substantial impact on various life domains such as work, interpersonal relations, mobility and social and mental well-being. How to adjust to the loss of vision and its consequences might be a challenge for the visually impaired person. The purpose of the current study was to explore how younger male ex-Service personnel cope with becoming visually impaired and how this affects their daily life. Semi-structured interviews with 30 visually impaired male ex-Service personnel, all under the age of 55, were conducted. All participants are members of the charity organisation Blind Veterans UK. Interviews were analysed thematically. Younger ex-Service personnel applied a number of different strategies to overcome their loss of vision and its associated consequences. Coping strategies varied from learning new skills, goal setting, integrating the use of low vision aids in their daily routine, to social withdrawal and substance misuse. Vision loss affected on all aspects of daily life and ex-Service personnel experienced an on-going struggle to accept and adjust to becoming visually impaired. Health care professionals, family and friends of the person with the visual impairment need to be aware that coping with a visual impairment is a continuous struggle; even after a considerable amount of time has passed, needs for emotional, social, practical and physical support may still be present.

Association of Axial Length With Risk of Uncorrectable Visual Impairment for Europeans With Myopia.

PubMed

Tideman, J Willem L; Snabel, Margaretha C C; Tedja, Milly S; van Rijn, Gwyneth A; Wong, King T; Kuijpers, Robert W A M; Vingerling, Johannes R; Hofman, Albert; Buitendijk, Gabriëlle H S; Keunen, Jan E E; Boon, Camiel J F; Geerards, Annette J M; Luyten, Gregorius P M; Verhoeven, Virginie J M; Klaver, Caroline C W

2016-12-01

Myopia (ie, nearsightedness) is becoming the most common eye disorder to cause blindness in younger persons in many parts of the world. Visual impairment due to myopia is associated with structural changes of the retina and the globe because of elongation of the eye axis. How axial length-a sum of the anterior chamber depth, lens thickness, and vitreous chamber depth-and myopia relate to the development of visual impairment over time is unknown. To evaluate the association between axial length, spherical equivalent, and the risk of visual impairment and to make projections of visual impairment for regions with high prevalence rates. This cross-sectional study uses population-based data from the Rotterdam Study I (1990 to 1993), II (2000 to 2002), and III (2006 to 2008) and the Erasmus Rucphen Family Study (2002 to 2005) as well as case-control data from the Myopia Study (2010 to 2012) from the Netherlands. In total, 15 404 individuals with data on spherical equivalent and 9074 individuals with data on axial length were included in the study; right eyes were used for analyses. Data were analyzed from September 2014 to May 2016. Visual impairment and blindness (defined according to the World Health Organization criteria as a visual acuity less than 0.3) and predicted rates of visual impairment specifically for persons with myopia. Of the 15 693 individuals included in this study, the mean (SD) age was 61.3 (11.4) years, and 8961 (57.1%) were female. Axial length ranged from 15.3 to 37.8 mm; 819 individuals had an axial length of 26 mm or greater. Spherical equivalent ranged from -25 to +14 diopters; 796 persons had high myopia (ie, a spherical equivalent of -6 diopters or less). The prevalence of visual impairment varied from 1.0% to 4.1% in the population-based studies, was 5.4% in the Myopia Study, and was 0.3% in controls. The prevalence of visual impairment rose with increasing axial length and spherical equivalent, with a cumulative incidence (SE) of visual impairment of 3.8% (1.3) for participants aged 75 years with an axial length of 24 to less than 26 mm and greater than 90% (8.1) with an axial length of 30 mm or greater. The cumulative risk (SE) of visual impairment was 5.7% (1.3) for participants aged 60 years and 39% (4.9) for those aged 75 years with a spherical equivalent of -6 diopters or less. Projections of these data suggest that visual impairment will increase 7- to 13-fold by 2055 in high-risk areas. This study demonstrated that visual impairment is associated with axial length and spherical equivalent and may be unavoidable at the most extreme values in this population. Developing strategies to prevent the development of myopia and its complications could help to avoid an increase of visual impairment in the working-age population.

Risk Factors for Visual Impairment in an Uninsured Population and the Impact of the Affordable Care Act.

PubMed

Guo, Weixia; Woodward, Maria A; Heisler, Michele; Blachley, Taylor; Corneail, Leah; Cederna, Jean; Kaplan, Ariane D; Newman Casey, Paula Anne

2016-01-01

To assess risk factors for visual impairment in a high-risk population of people: those without medical insurance. Secondarily, we assessed risk factors for remaining uninsured after implementation of the Affordable Care Act (ACA) and evaluated whether the ACA changed demand for local safety net ophthalmology clinic services one year after its implementation. In a retrospective cohort study of patients who attended a community-academic partnership free ophthalmology clinic in Southeastern, Michigan between September 2012 - March 2015, we assessed the prevalence of presenting with visual impairment, the most common causes of presenting with visual impairment and used logistic regression to assess socio-demographic risk factors for visual impairment. We assessed the initial impact of the ACA on clinic utilization. We also analyzed risk factors for remaining uninsured one year after implementation of the ACA private insurance marketplace and Medicaid expansion in the state of Michigan. Among 335 patients, one-fifth (22%) presented with visual impairment; refractive error was the leading cause for presenting with visual impairment. Unemployment was the single significant risk factor for presenting with visual impairment after adjusting for multiple confounding factors (OR = 3.05, 95% CI 1.19-7.87, p=0.01). There was no difference in proportion of visual impairment or type of vision-threatening disease between the insured and uninsured (p=0.26). Seventy six percent of patients remained uninsured one year after ACA implementation. Patients who were white, spoke English as a first language and were US Citizens were more likely to gain insurance coverage through the ACA in our population (p≤ 0.01). There was a non-significant decline in the mean number of patient treated per clinic (52 to 43) before and after ACA implementation (p=0.69). Refractive error was a leading cause for presenting with visual impairment in this vulnerable population, and being unemployed significantly increased the risk for presenting with visual impairment. The ACA did not significantly reduce the need for our free ophthalmology services. It is critically important to continue to support safety net specialty care initiatives and policy change to provide care for those in need.

Risk Factors for Visual Impairment in an Uninsured Population and the Impact of the Affordable Care Act

PubMed Central

Guo, Weixia; Woodward, Maria A; Heisler, Michele; Blachley, Taylor; Corneail, Leah; Cederna, Jean; Kaplan, Ariane D; Newman Casey, Paula Anne

2017-01-01

Purpose To assess risk factors for visual impairment in a high-risk population of people: those without medical insurance. Secondarily, we assessed risk factors for remaining uninsured after implementation of the Affordable Care Act (ACA) and evaluated whether the ACA changed demand for local safety net ophthalmology clinic services one year after its implementation. Methods In a retrospective cohort study of patients who attended a community-academic partnership free ophthalmology clinic in Southeastern, Michigan between September 2012 – March 2015, we assessed the prevalence of presenting with visual impairment, the most common causes of presenting with visual impairment and used logistic regression to assess socio-demographic risk factors for visual impairment. We assessed the initial impact of the ACA on clinic utilization. We also analyzed risk factors for remaining uninsured one year after implementation of the ACA private insurance marketplace and Medicaid expansion in the state of Michigan. Results Among 335 patients, one-fifth (22%) presented with visual impairment; refractive error was the leading cause for presenting with visual impairment. Unemployment was the single significant risk factor for presenting with visual impairment after adjusting for multiple confounding factors (OR = 3.05, 95% CI 1.19–7.87, p=0.01). There was no difference in proportion of visual impairment or type of vision-threatening disease between the insured and uninsured (p=0.26). Seventy six percent of patients remained uninsured one year after ACA implementation. Patients who were white, spoke English as a first language and were US Citizens were more likely to gain insurance coverage through the ACA in our population (p≤ 0.01). There was a non-significant decline in the mean number of patient treated per clinic (52 to 43) before and after ACA implementation (p=0.69). Conclusion Refractive error was a leading cause for presenting with visual impairment in this vulnerable population, and being unemployed significantly increased the risk for presenting with visual impairment. The ACA did not significantly reduce the need for our free ophthalmology services. It is critically important to continue to support safety net specialty care initiatives and policy change to provide care for those in need. PMID:28593201

Situational analysis of communication of HIV and AIDS information to persons with visual impairment: a case of Kang'onga Production Centre in Ndola, Zambia.

PubMed

Chintende, Grace Nsangwe; Sitali, Doreen; Michelo, Charles; Mweemba, Oliver

2017-04-04

Despite the increases in health promotion and educational programs on HIV and AIDS, lack of information and communication on HIV and AIDS for the visually impaired persons continues. The underlying factors that create the information and communication gaps have not been fully explored in Zambia. It is therefore important that, this situational analysis on HIV and AIDS information dissemination to persons with visual impairments at Kang'onga Production Centre in Ndola was conducted. The study commenced in December 2014 to May 2015. A qualitative case study design was employed. The study used two focus group discussions with males and females. Each group comprised twelve participants. Eight in-depth interviews involving the visually impaired persons and five key informants working with visually impaired persons were conducted. Data was analysed thematically using NVIVO 8 software. Ethical clearance was sought from Excellency in Research Ethics and Science. Reference Number 2014-May-030. It was established that most visually impaired people lacked knowledge on the cause, transmission and treatment of HIV and AIDS resulting in misconceptions. It was revealed that health promoters and people working with the visually impaired did not have specific HIV and AIDS information programs in Zambia. Further, it was discovered that the media, information education communication and health education were channels through which the visually impaired accessed HIV and AIDS information. Discrimination, stigma, lack of employment opportunities, funding and poverty were among the many challenges identified which the visually impaired persons faced in accessing HIV and AIDS information. Integration of the visually impaired in HIV and AIDS programs would increase funding for economic empowerment and health promotions in order to improve communication on HIV and AIDS information. The study showed that, the visually impaired persons in Zambia are not catered for in the dissemination of HIV and AIDS information. Available information is not user-friendly because it is in unreadable formats thereby increasing the potential for misinformation and limitations to their access. This calls for innovations in the communication on HIV and AIDS information health promotion to the target groups.

Acute Sleep Deprivation and Circadian Misalignment Associated with Transition onto the First Night of Work Impairs Visual Selective Attention

PubMed Central

Santhi, Nayantara; Horowitz, Todd S.; Duffy, Jeanne F.; Czeisler, Charles A.

2007-01-01

Background Overnight operations pose a challenge because our circadian biology promotes sleepiness and dissipates wakefulness at night. Since the circadian effect on cognitive functions magnifies with increasing sleep pressure, cognitive deficits associated with night work are likely to be most acute with extended wakefulness, such as during the transition from a day shift to night shift. Methodology/Principal Findings To test this hypothesis we measured selective attention (with visual search), vigilance (with Psychomotor Vigilance Task [PVT]) and alertness (with a visual analog scale) in a shift work simulation protocol, which included four day shifts followed by three night shifts. There was a nocturnal decline in cognitive processes, some of which were most pronounced on the first night shift. The nighttime decrease in visual search sensitivity was most pronounced on the first night compared with subsequent nights (p = .04), and this was accompanied by a trend towards selective attention becoming ‘fast and sloppy’. The nighttime increase in attentional lapses on the PVT was significantly greater on the first night compared to subsequent nights (p<.05) indicating an impaired ability to sustain focus. The nighttime decrease in subjective alertness was also greatest on the first night compared with subsequent nights (p<.05). Conclusions/Significance These nocturnal deficits in attention and alertness offer some insight into why occupational errors, accidents, and injuries are pronounced during night work compared to day work. Examination of the nighttime vulnerabilities underlying the deployment of attention can be informative for the design of optimal work schedules and the implementation of effective countermeasures for performance deficits during night work. PMID:18043740

Association between visual impairment and patient-reported visual disability at different stages of cataract surgery.

PubMed

Acosta-Rojas, E Ruthy; Comas, Mercè; Sala, Maria; Castells, Xavier

2006-10-01

To evaluate the association between visual impairment (visual acuity, contrast sensitivity, stereopsis) and patient-reported visual disability at different stages of cataract surgery. A cohort of 104 patients aged 60 years and over with bilateral cataract was assessed preoperatively, after first-eye surgery (monocular pseudophakia) and after second-eye surgery (binocular pseudophakia). Partial correlation coefficients (PCC) and linear regression models were calculated. In patients with bilateral cataracts, visual disability was associated with visual acuity (PCC = -0.30) and, to a lesser extent, with contrast sensitivity (PCC = 0.16) and stereopsis (PCC = -0.09). In monocular and binocular pseudophakia, visual disability was more strongly associated with stereopsis (PCC = -0.26 monocular and -0.51 binocular) and contrast sensitivity (PCC = 0.18 monocular and 0.34 binocular) than with visual acuity (PCC = -0.18 monocular and -0.18 binocular). Visual acuity, contrast sensitivity and stereopsis accounted for between 17% and 42% of variance in visual disability. The association of visual impairment with patient-reported visual disability differed at each stage of cataract surgery. Measuring other forms of visual impairment independently from visual acuity, such as contrast sensitivity or stereopsis, could be important in evaluating both needs and outcomes in cataract surgery. More comprehensive assessment of the impact of cataract on patients should include measurement of both visual impairment and visual disability.

When May a Child Who Is Visually Impaired Recognize a Face?

ERIC Educational Resources Information Center

Markham, R.; Wyver, S.

1996-01-01

The ability of 16 school-age children with visual impairments and their sighted peers to recognize faces was compared. Although no intergroup differences were found in ability to identify entire faces, the visually impaired children were at a disadvantage when part of the face, especially the eyes, was not visible. Degree of visual acuity also…

Design and Usability Testing of an Audio Platform Game for Players with Visual Impairments

ERIC Educational Resources Information Center

Oren, Michael; Harding, Chris; Bonebright, Terri L.

2008-01-01

This article reports on the evaluation of a novel audio platform game that creates a spatial, interactive experience via audio cues. A pilot study with players with visual impairments, and usability testing comparing the visual and audio game versions using both sighted players and players with visual impairments, revealed that all the…

A Comparison of the Handwriting Abilities of Secondary Students with Visual Impairments and Those of Sighted Students

ERIC Educational Resources Information Center

Harris-Brown, Talitha; Richmond, Janet; Maddalena, Sebastian Della; Jaworski, Alinta

2015-01-01

Despite the large number of people with visual impairments in Australia, all Western Australian secondary students are required to complete their secondary exams using handwriting, unless they qualify for special provisions. Students with visual impairments do not necessarily qualify for special provisions on the basis of their visual impairment…

Developing a Schedule to Identify Social Communication Difficulties and Autism Spectrum Disorder in Young Children with Visual Impairment

ERIC Educational Resources Information Center

Absoud, Michael; Parr, Jeremy R.; Salt, Alison; Dale, Naomi

2011-01-01

Available observational tools used in the identification of social communication difficulties and diagnosis of autism spectrum disorder (ASD) rely partly on visual behaviours and therefore may not be valid in children with visual impairment. A pilot observational instrument, the Visual Impairment and Social Communication Schedule (VISS), was…

A Visual Skills Inventory for Children with Neurological Impairments

ERIC Educational Resources Information Center

McCulloch, D. L.; Mackie, R. T.; Dutton, G. N.; Bradnam, M. S.; Day, R. E.; McDaid, G. J.; Phillips, S.; Napier, A.; Herbert, A. M.; Saunders, K. J.; Shepherd, A. J.

2007-01-01

Children with neurological impairments often have visual deficits that are difficult to quantify. We have compared visual skills evaluated by carers with results of a comprehensive visual assessment. Participants were 76 children with mild to profound intellectual and/or motor impairment (33 males, 43 females; age range 7mo-16y; mean age 5y 1mo…

Frequency and Correlates of Distant Visual Impairment in Patients with Schizophrenia, Bipolar Disorder, and Major Depressive Disorder.

PubMed

Zheng, W; Tang, L R; Correll, C U; Ungvari, G S; Chiu, H F K; Xiang, Y Q; Xiang, Y T

2015-09-01

Distant visual impairment in the severely mentally ill is under-researched. This study aimed to assess the frequency and correlates of distant visual impairment in a cohort of Chinese psychiatric patients, including its effect on their quality of life. Adult psychiatric inpatients with schizophrenia, bipolar disorder, and major depressive disorder consecutively admitted to a psychiatric hospital in Beijing, China underwent assessments of psychopathology (Brief Psychiatric Rating Scale, 16-item Quick Inventory of Depressive Symptomatology [Self-Report]), quality of life (12-item Short-Form Medical Outcomes Study [SF-12], 25-item National Eye Institute Visual Function Questionnaire [NEI-VFQ25]), adverse effects (Udvalg for Kliniske Undersøgelser Side Effect Rating Scale), and presenting (as opposed to uncorrected) distant visual acuity (Logarithm of the Minimum Angle of Resolution [LogMAR] chart with patients wearing spectacles, if they owned them). Distant visual impairment was defined as binocular distant visual acuity of a LogMAR score of ≥ 0.5 (< 6/18 Snellen acuity). Among 356 patients who met the study criteria, the frequency of distant visual impairment was 12.6% (15.2% with schizophrenia, 11.9% with bipolar disorder, 8.8% with major depressive disorder). In multiple logistic regression analysis, distant visual impairment was significantly associated with ocular disease only (p = 0.002, odds ratio = 3.2, 95% confidence interval = 1.5-6.7). Controlling for the confounding effect of ocular disease, patients with distant visual impairment had a lower quality of life in the general vision domain of the NEI-VFQ25 (F[2, 353] = 9.5, p = 0.002) compared with those without. No differences in the physical and mental domains of the SF-12 and in other domains of the NEI-VFQ25 were noted in these 2 groups. One-eighth of middle-aged severely mentally ill patients had distant visual impairment. Considering the impact of distant visual impairment on daily functioning, severely mentally ill patients need to be screened for impaired eyesight as part of their comprehensive health assessment.

The impact of visual impairment on the ability to perform activities of daily living for persons with severe/profound intellectual disability.

PubMed

Dijkhuizen, Annemarie; Hilgenkamp, Thessa I M; Krijnen, Wim P; van der Schans, Cees P; Waninge, Aly

2016-01-01

The ability to perform activities of daily living (ADL) as a component of participation is one of the factors that contribute to quality of life. The ability to perform ADL for persons experiencing severe/profound intellectual disability (ID) may be reduced due to their cognitive and physical capacities. However, until recently, the impact of the significantly prevalent visual impairments on the performance of activities of daily living has not yet been revealed within this group. The purpose of this prospective cross-sectional study was to investigate the impact of visual impairment on the performance of activities of daily living for persons with a severe/profound intellectual disability. The Barthel Index (BI) and Comfortable Walking Speed (CWS) were used to measure the ability of performing activities of daily living (ADL) in 240 persons with severe/profound ID and having Gross Motor Functioning Classification System (GMFCS) levels I, II or III; this included 120 persons with visual impairment. The impact of visual impairment on ADL was analyzed with linear regression. The results of the study demonstrated that visual impairment slightly affects the ability of performing activities of daily living (BI) for persons experiencing a severe/profound intellectual disability. GMFCS Levels II or III, profound ID level, and visual impairment each have the effect of lowering BI scores. GMFCS Levels II or III, and profound ID level each have the effect of increasing CWS scores, which indicates a lower walking speed. A main effect of visual impairment is present on CWS, but our results do show a substantive interaction effect between GMFCS level III and visual impairment on Comfortable Walking Speed in persons with a severe/profound intellectual disability. Visual impairment has a slight effect on ability to perform ADL in persons experiencing severe/profound ID. Copyright © 2015 Elsevier Ltd. All rights reserved.

Social care and support needs of community-dwelling people with dementia and concurrent visual impairment.

PubMed

Nyman, Samuel Robert; Innes, Anthea; Heward, Michelle

2017-09-01

This study explored the social care and support needs of people with dementia and visual impairment, and the barriers and facilitators for meeting these needs. Twenty-six semi-structured interviews were conducted: 21 joint and 5 individual interviews with the person with dementia and visual impairment (n=4) or their family/paid carer (n=1). Interviews were analysed thematically. Three themes are presented. (1) Social care needs: having dementia can reduce an individual's ability to cope with their visual impairment, and lead to increased dependency and reduced daily stimulation. (2) Barriers to using technology to meet social care needs: difficulties were reported with learning to use unfamiliar technology and the cost of visual impairment aids, and for some, the presence of dementia made visual impairment aids unusable and vice versa. (3) Familiarity as a facilitator for meeting social care needs: living at home or taking furnishings and ornaments into a new home facilitated independence, and continuity of paid carers/volunteers facilitated the caring relationship between the individual and staff/volunteer. Care workers will better serve older people if they are aware of the social care and support needs that arise from having both dementia and visual impairment.

Design and evaluation of a kitchen for persons with visual impairments.

PubMed

Kutintara, Benjamas; Somboon, Pornpun; Buasri, Virajada; Srettananurak, Metinee; Jedeeyod, Piyanooch; Pornpratoom, Kittikan; Iam-cham, Veraya

2013-03-01

Visually impaired people need skills on daily living, such as cooking, and Ratchasuda College offers independent living training for them. In order to fulfill their needs, a suitable kitchen should be designed with the consideration of their limitations. The objective of this study was to design and evaluate a kitchen for persons with visual impairments. Before designing the kitchen, interviews and an observation were carried out to obtain information on the needs of blind and low vision persons. Consequently, a kitchen model was developed, and it was evaluated by 10 persons with visual impairments. After the design improvement, the kitchen was built and has been routinely used for training persons with visual impairments to prepare meals. Finally, a post-occupancy evaluation of the kitchen was conducted by observing and interviewing both trainers and those with visual impairments during the food preparation training. The results of the study indicated that kitchens for persons with visual impairments should have safety and usability features. The results of the post-occupancy evaluation showed that those who attended cooking courses were able to cook safely in the kitchen. However, the kitchen still had limitations in some features.

Visual memory and learning in extremely low-birth-weight/extremely preterm adolescents compared with controls: a geographic study.

PubMed

Molloy, Carly S; Wilson-Ching, Michelle; Doyle, Lex W; Anderson, Vicki A; Anderson, Peter J

2014-04-01

Contemporary data on visual memory and learning in survivors born extremely preterm (EP; <28 weeks gestation) or with extremely low birth weight (ELBW; <1,000 g) are lacking. Geographically determined cohort study of 298 consecutive EP/ELBW survivors born in 1991 and 1992, and 262 randomly selected normal-birth-weight controls. Visual learning and memory data were available for 221 (74.2%) EP/ELBW subjects and 159 (60.7%) controls. EP/ELBW adolescents exhibited significantly poorer performance across visual memory and learning variables compared with controls. Visual learning and delayed visual memory were particularly problematic and remained so after controlling for visual-motor integration and visual perception and excluding adolescents with neurosensory disability, and/or IQ <70. Male EP/ELBW adolescents or those treated with corticosteroids had poorer outcomes. EP/ELBW adolescents have poorer visual memory and learning outcomes compared with controls, which cannot be entirely explained by poor visual perceptual or visual constructional skills or intellectual impairment.

A Customized Transportation Intervention for Persons with Visual Impairments

ERIC Educational Resources Information Center

Crudden, Adele; Antonelli, Karla; O'Mally, Jamie

2017-01-01

Introduction: Transportation can be an employment barrier for persons with disabilities, particularly those with visual impairments. A customized transportation intervention for people with visual impairments, based on concepts associated with customized employment, was devised, implemented, and evaluated. Methods: A pretest and posttest…

Visual perception and appraisal of persons with impairments: a randomised controlled field experiment using photo elicitation.

PubMed

Reinhardt, Jan Dietrich; Ballert, Carolina Saskia; Fellinghauer, Bernd; Lötscher, Alexander; Gradinger, Felix; Hilfiker, Roger; Graf, Sibylle; Stucki, Gerold

2011-01-01

Visual cues from persons with impairments may trigger stereotypical generalisations that lead to prejudice and discrimination. The main objective of this pilot study is to examine whether visual stimuli of impairment activate latent prejudice against disability and whether this connection can be counteracted with priming strategies. In a field experiment, participants were asked to rate photographs showing models with mental impairments, wheelchair users with paraplegia, and persons without any visible impairment. Participants should appraise the models with regard to several features (e.g. communicativeness, intelligence). One hundred participants rated 12 photo models yielding a total of 1183 observations. One group of participants was primed with a cover story introducing visual perception of impairment as the study's gist, while controls received neutral information. Photo models with mental impairments were rated lowest and models without visible impairment highest. In participants who did not have prior contacts with persons with impairments, priming led to a levelling of scores of models with and without impairment. Prior contacts with persons with impairments created similar effects as the priming. Unexpectedly, a pattern of converse double discrimination to the disadvantage of men with mental impairments was revealed. Signs of stereotypical processing of visual cues of impairment have been found in participants of the Swiss general population. Personal contact with persons with impairments as well as priming participants seems to reduce stereotyping.

The Doors and People Test: The Effect of Frontal Lobe Lesions on Recall and Recognition Memory Performance

PubMed Central

2016-01-01

Objective: Memory deficits in patients with frontal lobe lesions are most apparent on free recall tasks that require the selection, initiation, and implementation of retrieval strategies. The effect of frontal lesions on recognition memory performance is less clear with some studies reporting recognition memory impairments but others not. The majority of these studies do not directly compare recall and recognition within the same group of frontal patients, assessing only recall or recognition memory performance. Other studies that do compare recall and recognition in the same frontal group do not consider recall or recognition tests that are comparable for difficulty. Recognition memory impairments may not be reported because recognition memory tasks are less demanding. Method: This study aimed to investigate recall and recognition impairments in the same group of 47 frontal patients and 78 healthy controls. The Doors and People Test was administered as a neuropsychological test of memory as it assesses both verbal and visual recall and recognition using subtests that are matched for difficulty. Results: Significant verbal and visual recall and recognition impairments were found in the frontal patients. Conclusion: These results demonstrate that when frontal patients are assessed on recall and recognition memory tests of comparable difficulty, memory impairments are found on both types of episodic memory test. PMID:26752123

The Doors and People Test: The effect of frontal lobe lesions on recall and recognition memory performance.

PubMed

MacPherson, Sarah E; Turner, Martha S; Bozzali, Marco; Cipolotti, Lisa; Shallice, Tim

2016-03-01

Memory deficits in patients with frontal lobe lesions are most apparent on free recall tasks that require the selection, initiation, and implementation of retrieval strategies. The effect of frontal lesions on recognition memory performance is less clear with some studies reporting recognition memory impairments but others not. The majority of these studies do not directly compare recall and recognition within the same group of frontal patients, assessing only recall or recognition memory performance. Other studies that do compare recall and recognition in the same frontal group do not consider recall or recognition tests that are comparable for difficulty. Recognition memory impairments may not be reported because recognition memory tasks are less demanding. This study aimed to investigate recall and recognition impairments in the same group of 47 frontal patients and 78 healthy controls. The Doors and People Test was administered as a neuropsychological test of memory as it assesses both verbal and visual recall and recognition using subtests that are matched for difficulty. Significant verbal and visual recall and recognition impairments were found in the frontal patients. These results demonstrate that when frontal patients are assessed on recall and recognition memory tests of comparable difficulty, memory impairments are found on both types of episodic memory test. (c) 2016 APA, all rights reserved).

Representations of temporal information in short-term memory: Are they modality-specific?

PubMed

Bratzke, Daniel; Quinn, Katrina R; Ulrich, Rolf; Bausenhart, Karin M

2016-10-01

Rattat and Picard (2012) reported that the coding of temporal information in short-term memory is modality-specific, that is, temporal information received via the visual (auditory) modality is stored as a visual (auditory) code. This conclusion was supported by modality-specific interference effects on visual and auditory duration discrimination, which were induced by secondary tasks (visual tracking or articulatory suppression), presented during a retention interval. The present study assessed the stability of these modality-specific interference effects. Our study did not replicate the selective interference pattern but rather indicated that articulatory suppression not only impairs short-term memory for auditory but also for visual durations. This result pattern supports a crossmodal or an abstract view of temporal encoding. Copyright © 2016 Elsevier B.V. All rights reserved.

The association between socioeconomic status and visual impairments among primary glaucoma: the results from Nationwide Korean National Health Insurance Cohort from 2004 to 2013.

PubMed

Sung, Haejune; Shin, Hyun Ho; Baek, Yunseng; Kim, Gyu Ah; Koh, Jae Sang; Park, Eun-Cheol; Shin, Jaeyong

2017-08-23

Glaucoma is one of the most leading causes of permanent visual impairments in Korea, and social expenses spent for the glaucoma are increasing. This study is to identify association between socioeconomic status and the visual impairments caused by primary glaucoma in Korea. This study is based on a cohort study using stratified representative samples in the National Health Insurance claim data from 2002 to 2013 with 1,025,340 representative subjects. Target subjects were patients who are newly diagnosed with primary glaucoma from 2004 to 2013. We conducted a multiple logistic regression analysis depending on the occurrence of visual impairment and its temporal order compared to the glaucoma diagnosis. Among 1728 patients with primary glaucoma, those with low and middle income shows higher odds ratio (OR) of the visual impairments than those with high income group (low income; OR = 3.42, 95% Confidential Interval (CI):2.06-5.66, middle income; OR = 2.13, 95% CI: 1.28-3.55), in case of the occurrence of the visual impairments preceded the diagnosis of glaucoma. Glaucoma patients without pre-existing glaucoma history before visual impairment have higher association between socioeconomic status and the occurrence of visual impairments by primary glaucoma. Since glaucoma had not been diagnosed and recognized yet, the differences may have been derived from the disparities of the awareness of the glaucoma. These findings call attention to the correlation between socioeconomic factors and the visual impairments by glaucoma, and raise public health needs over the importance of glaucoma awareness and eye screening for glaucoma, especially for low socioeconomic status.

[Issues in psychiatric evaluation of children and adolescents with visual impairment].

PubMed

Saisky, Yaniv; Hasid, Soli; Ebert, Tanya; Kosov, Irene

2014-02-01

Approximately 8% from those who are defined as blind in Israel are children and adolescents. Visual impairment is correlated with a high rate of psychopathology. However, some of these children and adolescents do not receive appropriate diagnosis and treatment. Often, the clinicians and those who treat the children/adolescents lack the proper professional knowledge related to the unique diagnosis and treatment of children/ adolescents who are visually impaired. Visual impairment might influence different aspects of the psychiatric diagnosis. These aspects include the influence of the impairment on different developmental axes; the reciprocal relationship between the child and his/her environment; the clinical presentation of different psychopathologies; and the different treatment modalities. In this review we discuss these issues. Moreover, we raise the question as to whether there is a need to adapt the psychiatric evaluation and the treatment specifically to the visually impaired child. The review is based on the existing literature in addition to our clinical experience, which stems from our work with children and adolescents who are at the "Jewish Institute for the Blind", an institute for children and adolescents with visual impairment in Israel.

Reading Materials in Large Print: A Resource Guide. Reference Circular No. 97-02.

ERIC Educational Resources Information Center

Mendle, Gillian, Comp.

This reference circular contains information about large-print materials. Section 1 is an annotated list of selected sources of large-print materials available for purchase or loan. The sources are publishers or distributors, specialized libraries, and associations for persons with visual impairments. Several of these sources also provide general…

Teaching Identity Matching of Braille Characters to Beginning Braille Readers

ERIC Educational Resources Information Center

Toussaint, Karen A.; Scheithauer, Mindy C.; Tiger, Jeffrey H.; Saunders, Kathryn J.

2017-01-01

We taught three children with visual impairments to make tactile discriminations of the braille alphabet within a matching-to-sample format. That is, we presented participants with a braille character as a sample stimulus, and they selected the matching stimulus from a three-comparison array. In order to minimize participant errors, we initially…

Prevalence and Causes of Visual Impairment and Blindness in Shanxi Province, China.

PubMed

Li, Tong; Du, Liping; Du, Lingzhen

2015-01-01

To estimate the prevalence and causes of visual impairment and blindness in Shanxi Province, China. Data were obtained from the Second National Sampling Survey of Disability conducted in 2006. Blindness and visual impairment were defined as best corrected visual acuity <3/60 and <6/18, respectively, in the better-seeing eye. Standardized ophthalmologic examinations were administered to participants aged 0-80 years in 2006. Visual acuity (VA) was measured using a Standard Logarithmic Visual Acuity E chart (Snellen) for subjects aged 7 years and older. Participants younger than 7 years were examined using special experiments or the Childhood Graphical Visual Chart. The prevalence of visual impairment and blindness in Shanxi was estimated to be 0.6% (466/75,016) among persons up to 80 years old. The prevalence in rural areas (0.7%; 351/48,137) was significantly higher than that in urban areas (0.4%; 115/26,879) and was higher in females (0.8%; 298/36,933) than in males (0.4%; 168/38,083). The most common cause of visual impairment and blindness was cataract (44.9%), followed by retinopathy and choroidopathy (12.5%), hereditary and developmental disorders (10.3%), corneal disease (5.2%), and refractive error (4.9%). Prevalences of visual impairment and blindness in women and in rural areas were higher than in men and urban areas, and increased with age. Cataract was the most prevalent cause of visual impairment and blindness. Based on the findings from this study, we suggest that provision of support and welfare services should be organized.

Space Activities for the Visually Impaired

NASA Astrophysics Data System (ADS)

Ries, J. G.; Baguio, M.

2005-12-01

To a visually impaired person celestial objects or concepts of space exploration are likely to be more abstract than to other people, but they encounter news about the universe through their daily life. A partnership between Texas Space Grant Consortium, The University of Texas at Austin, and the Texas School for the Blind and Visually Impaired provided the opportunity to assist visually impaired students increase their understanding of astronomy and space science. The activities helped visually impaired students activity engage in inquiry-based, hands-on astronomy activities. The experiences provided during the educator workshops, adapted instructional classroom activities, and tactile learning aids will be shared in the hopes that others may be able to incorporate these lessons into their regular teaching activities.

Experiences of Visually Impaired Students in Community College Math Courses

NASA Astrophysics Data System (ADS)

Swan, S. Tomeka

Blind and visually impaired students who attend community colleges face challenges in learning mathematics (Forrest, 2010). Scoy, McLaughlin, Walls, and Zuppuhaur (2006) claim these students are at a disadvantage in studying mathematics due to the visual and interactive nature of the subject, and by the way mathematics is taught. In this qualitative study six blind and visually impaired students attended three community colleges in one Mid-Atlantic state. They shared their experiences inside the mathematics classroom. Five of the students were enrolled in developmental level math, and one student was enrolled in college level math. The conceptual framework used to explore how blind and visually impaired students persist and succeed in math courses was Piaget's theory on constructivism. The data from this qualitative study was obtained through personal interviews. Based on the findings of this study, blind and visually impaired students need the following accommodations in order to succeed in community college math courses: Accommodating instructors who help to keep blind and visually impaired students motivated and facilitate their academic progress towards math completion, tutorial support, assistive technology, and a positive and inclusive learning environment.

Disease and Surgery of the Equine Lens.

PubMed

Townsend, Wendy M

2017-12-01

Examination of the lens is critical, particularly when evaluating horses with visual impairment or performing prepurchase examinations. To adequately evaluate the lens, the pupil must be pharmacologically dilated. A cataract is any lens opacity. The size, density, and position of a cataract determine the impact on vision. Cataracts may be congenital or inherited or occur secondary to trauma or equine recurrent uveitis. Surgical removal is the only treatment option for vision impairing cataracts, but careful selection of surgical candidates is critical for successful outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

The Challenges of Educating the Visually Impaired and Quality Assurance in Tertiary Institutions of Learning in Nigeria

ERIC Educational Resources Information Center

Omede, Andrew A.

2015-01-01

This paper focused on the challenges in educating the visually impaired and modalities for ensuring quality assurance in tertiary institutions of learning in Nigeria. It examined the global challenges in the higher educational system and made it clear that the visually impaired are those with visual problems be it partial, low vision, or total…

Windows to the soul: vision science as a tool for studying biological mechanisms of information processing deficits in schizophrenia.

PubMed

Yoon, Jong H; Sheremata, Summer L; Rokem, Ariel; Silver, Michael A

2013-10-31

Cognitive and information processing deficits are core features and important sources of disability in schizophrenia. Our understanding of the neural substrates of these deficits remains incomplete, in large part because the complexity of impairments in schizophrenia makes the identification of specific deficits very challenging. Vision science presents unique opportunities in this regard: many years of basic research have led to detailed characterization of relationships between structure and function in the early visual system and have produced sophisticated methods to quantify visual perception and characterize its neural substrates. We present a selective review of research that illustrates the opportunities for discovery provided by visual studies in schizophrenia. We highlight work that has been particularly effective in applying vision science methods to identify specific neural abnormalities underlying information processing deficits in schizophrenia. In addition, we describe studies that have utilized psychophysical experimental designs that mitigate generalized deficit confounds, thereby revealing specific visual impairments in schizophrenia. These studies contribute to accumulating evidence that early visual cortex is a useful experimental system for the study of local cortical circuit abnormalities in schizophrenia. The high degree of similarity across neocortical areas of neuronal subtypes and their patterns of connectivity suggests that insights obtained from the study of early visual cortex may be applicable to other brain regions. We conclude with a discussion of future studies that combine vision science and neuroimaging methods. These studies have the potential to address pressing questions in schizophrenia, including the dissociation of local circuit deficits vs. impairments in feedback modulation by cognitive processes such as spatial attention and working memory, and the relative contributions of glutamatergic and GABAergic deficits.

Communicative interactions between visually impaired mothers and their sighted children: analysis of gaze, facial expressions, voice and physical contacts.

PubMed

Chiesa, S; Galati, D; Schmidt, S

2015-11-01

Social and emotional development of infants and young children is largely based on the communicative interaction with their mother, or principal caretaker (Trevarthen ). The main modalities implied in this early communication are voice, facial expressions and gaze (Stern ). This study aims at analysing early mother-child interactions in the case of visually impaired mothers who do not have access to their children's gaze and facial expressions. Spontaneous play interactions between seven visually impaired mothers and their sighted children aged between 6 months and 3 years were filmed. These dyads were compared with a control group of sighted mothers and children analysing four modalities of communication and interaction regulation: gaze, physical contacts, verbal productions and facial expressions. The visually impaired mothers' facial expressions differed from the ones of sighted mothers mainly with respect to forehead movements, leading to an impoverishment of conveyed meaning. Regarding the other communicative modalities, results suggest that visually impaired mothers and their children use compensatory strategies to guaranty harmonic interaction despite the mother's impairment: whereas gaze results the main factor of interaction regulation in sighted dyads, physical contacts and verbal productions assume a prevalent role in dyads with visually impaired mothers. Moreover, visually impaired mother's children seem to be able to differentiate between their mother and sighted interaction partners, adapting differential modes of communication. The results of this study show that, in spite of the obvious differences in the modes of communication, visual impairment does not prevent a harmonious interaction with the child. © 2015 John Wiley & Sons Ltd.

Stress Associated with Transportation: A Survey of Persons with Visual Impairments

ERIC Educational Resources Information Center

Crudden, Adele; Cmar, Jennifer L.; McDonnall, Michele C.

2017-01-01

Introduction: This study evaluated transportation-related stress and factors predicting stress among persons with visual impairments. Methods: Participants with visual impairments completed electronic surveys rating their stress levels experienced when completing various walking and public transportation tasks. They also indicated activities they…

Affective Education for Visually Impaired Children.

ERIC Educational Resources Information Center

Locke, Don C.; Gerler, Edwin R., Jr.

1981-01-01

Evaluated the effectiveness of the Human Development Program (HDP) and the Developing Understanding of Self and Others (DUSO) program used with visually impaired children. Although HDP and DUSO affected the behavior of visually impaired children, they did not have any effect on children's attitudes toward school. (RC)

[Loneliness and self-management abilities in the visually impaired elderly].

PubMed

Alma, M A; Van der Mei, S F; Feitsma, W N; Groothoff, J W; Van Tilburg, T G; Suurmeijer, T P B M

2013-06-01

To describe the degree of loneliness among the visually impaired elderly and to make a comparison with a matched reference group of the normally sighted elderly. In addition, we examined self-management abilities (SMAs) as determinants of loneliness among the visually impaired elderly. In a cross-sectional study, 173 visually impaired elderly persons completed telephone interviews. Loneliness and SMAs were assessed with the Loneliness Scale of De Jong Gierveld and the SMAS-30, respectively. The prevalence of loneliness among the visually impaired elderly was higher compared to the reference group (50% vs 29%; p < .001). Multivariate hierarchical regression analysis showed that the SMA self-efficacy, partner status, and self-esteem were determinants of loneliness. Severity and duration of visual impairment had no effect on loneliness. The relationship between SMAs (i.e., self-efficacy) and loneliness is promising, since SMAs can be learned through training. Consequently, self-management training may reduce feelings of loneliness. An adapted version of this paper was published in Journal of Aging and Health, doi: 10.1177/0898264311399758.

Identifying and characterising cerebral visual impairment in children: a review.

PubMed

Philip, Swetha Sara; Dutton, Gordon N

2014-05-01

Cerebral visual impairment (CVI) comprises visual malfunction due to retro-chiasmal visual and visual association pathway pathology. This can be isolated or accompany anterior visual pathway dysfunction. It is a major cause of low vision in children in the developed and developing world due to increasing survival in paediatric and neonatal care. CVI can present in many combinations and degrees. There are multiple causes and it is common in children with cerebral palsy. CVI can be identified easily, if a structured approach to history-taking is employed. This review describes the features of CVI and describes practical management strategies aimed at helping affected children. A literature review was undertaken using 'Medline' and 'Pubmed'. Search terms included cerebral visual impairment, cortical visual impairment, dorsal stream dysfunction and visual function in cerebral palsy. © 2014 The Authors. Clinical and Experimental Optometry © 2014 Optometrists Association Australia.

Visual impairment and amblyopia in Malaysian pre-school children - The SEGPAEDS study.

PubMed

Chew, F L M; Thavaratnam, L K; Shukor, I N C; Ramasamy, S; Rahmat, J; Reidpath, D D; Allotey, P; Alagaratnam, J

2018-02-01

Little is known regarding the extent of visual impairment amongst pre-school children in Malaysia. To determine the prevalence of visual impairment and amblyopia in Malaysian preschool children. A cross-sectional, population-based study was conducted on children aged four to six years from 51 participating kindergartens in the district of Segamat, Johor, Malaysia from 20 March 2016 to 6 April 2016. All subjects had initial eye screening consisting of LogMar visual acuity, orthoptics examination and Spot vision screener assessment. Subjects who failed the initial eye screening were invited for a formal eye assessment consisting of cycloplegic refraction and a comprehensive ocular examination. Definitions of visual impairment and amblyopia were based on the Multi-Ethnic Pediatric Eye Disease Study criteria. A total of 1287 children were recruited. Mean subject age was 5.03 (SD:0.77) and males represented 52.3% of subjects. Subjects by ethnicity were Malay (54.8%), Chinese (27.7%), Indian (15.6%) and Orang Asli (1.9%). Formal eye assessment was required for 221 subjects and 88.8% required ophthalmic intervention. Refractive error, representing 95.4% of diagnosed ocular disorders, comprised of astigmatism (84%), myopia (9%) and hypermetropia (6.9%). With-the-rule astigmatism was present in 93.4% of the subjects with astigmatism. Visual impairment was present in 12.5% of our subjects, with 61% having bilateral visual impairment. Of the subjects with visual impairment, 59.1% had moderate visual impairment. The prevalence of amblyopia was 7.53%, and 66% of the amblyopic subjects had bilateral amblyopia. Our study highlights an urgent need for initiation of preschool vision screening in Malaysia.

Unhealthy behaviours and risk of visual impairment: The CONSTANCES population-based cohort.

PubMed

Merle, Bénédicte M J; Moreau, Gwendoline; Ozguler, Anna; Srour, Bernard; Cougnard-Grégoire, Audrey; Goldberg, Marcel; Zins, Marie; Delcourt, Cécile

2018-04-26

Unhealthy behaviours are linked to a higher risk of eye diseases, but their combined effect on visual function is unknown. We aimed to examine the individual and combined associations of diet, physical activity, smoking and alcohol consumption with visual impairment among French adults. 38 903 participants aged 18-73 years from the CONSTANCES nationwide cohort (2012-2016) with visual acuity measured and who completed, lifestyle, medical and food frequency questionnaires were included. Visual impairment was defined as a presenting visual acuity <20/40 in the better eye. After full multivariate adjustment, the odds for visual impairment increased with decreasing diet quality (p for trend = 0.04), decreasing physical activity (p for trend = 0.02) and increasing smoking pack-years (p for trend = 0.03), whereas no statistically significant association with alcohol consumption was found. Combination of several unhealthy behaviours was associated with increasing odds for visual impairment (p for trend = 0.0002), with a fully-adjusted odds ratio of 1.81 (95% CI 1.18 to 2.79) for participants reporting 2 unhealthy behaviours and 2.92 (95% CI 1.60 to 5.32) for those reporting 3 unhealthy behaviours. An unhealthy lifestyle including low/intermediate diet quality, low physical activity and heavy smoking was associated with visual impairment in this large population-based study.

Visual Impairment in Infants and Young Children.

ERIC Educational Resources Information Center

Teplin, Stuart W.

1995-01-01

This article reviews the structure, development, function, and assessment of the visual system and then considers: common eye problems of young children with visual impairment; impacts of severe impairment on child development; and the roles of early intervention professionals, ophthalmologists, and pediatricians in working with these children and…

38 CFR 17.149 - Sensori-neural aids.

Code of Federal Regulations, 2010 CFR

2010-07-01

... attendance or by reason of being permanently housebound; (6) Those who have a visual or hearing impairment... normally occurring visual or hearing impairments; and (8) Those visually or hearing impaired so severely... frequency ranges which contribute to a loss of communication ability; however, hearing aids are to be...

The screening of visual impairment among preschool children in an urban population in Malaysia; the Kuching pediatric eye study: a cross sectional study

PubMed Central

2013-01-01

Background To screen for visual impairment in Malaysian preschool children. Methods Visual screening was conducted in 400 preschool children aged 4 to 6 years. The screening involved two basic procedures; the distant visual acuity test using the Sheridan Gardiner chart and the depth perception test using the Langs stereoacuity test. Criteria for referral were a visual acuity of 6/12 or less in the better eye or a fail in the depth perception test. Results The prevalence of visual impairment was 5% (95% confidence interval [CI] = 3.3, 7.6). Of the 400 preschool children screened, 20 of them failed the distant visual acuity test or the stereopsis test. Refractive errors were the most common cause of visual impairment (95%, 95% CI = 76.2, 98.8); myopic astigmatism was the commonest type of refractive error (63.2%, 95% CI = 40.8, 80.9). Conclusion The study is a small but important step in the effort to understand the problem of visual impairment among our preschool children. Our study showed that it is feasible to measure distant visual acuity and stereopsis in this age group. PMID:23601160

The screening of visual impairment among preschool children in an urban population in Malaysia; the Kuching pediatric eye study: a cross sectional study.

PubMed

Premsenthil, Mallika; Manju, Rose; Thanaraj, Asokumaran; Rahman, Syed Alwi Syed Abdul; Kah, Tan Aik

2013-04-19

To screen for visual impairment in Malaysian preschool children. Visual screening was conducted in 400 preschool children aged 4 to 6 years. The screening involved two basic procedures; the distant visual acuity test using the Sheridan Gardiner chart and the depth perception test using the Langs stereoacuity test. Criteria for referral were a visual acuity of 6/12 or less in the better eye or a fail in the depth perception test. The prevalence of visual impairment was 5% (95% confidence interval [CI] = 3.3, 7.6). Of the 400 preschool children screened, 20 of them failed the distant visual acuity test or the stereopsis test. Refractive errors were the most common cause of visual impairment (95%, 95% CI = 76.2, 98.8); myopic astigmatism was the commonest type of refractive error (63.2%, 95% CI = 40.8, 80.9). The study is a small but important step in the effort to understand the problem of visual impairment among our preschool children. Our study showed that it is feasible to measure distant visual acuity and stereopsis in this age group.

[Challenges in Traffic for Blind and Visually Impaired People and Strategies for their Safe Participation].

PubMed

Högner, N

2015-08-01

Blind and visually impaired people experience special risks and hazards in road traffic. This refers to participation as a driver, bicycle rider and pedestrian. These risks are shown by a review of international research studies and a study by the author, where 45 people with Usher syndrome were asked about their accident rates and causes as driver, bicycle rider and pedestrian. In addition, basic legal information has been worked out to demonstrate the visual conditions of people with visual impairment for participation in road traffic. The research studies show that blind and visually impaired persons are particularly exposed to experience high risks in traffic. These risks can be reduced through acquisition of skills and coping strategies such as training in orientation and mobility. People with visual impairment need special programmes which help to reduce traffic hazards. Georg Thieme Verlag KG Stuttgart · New York.

Bilateral Coordination of Children who are Blind.

PubMed

Rutkowska, Izabela; Lieberman, Lauren J; Bednarczuk, Grzegorz; Molik, Bartosz; Kazimierska-Kowalewska, Kalina; Marszałek, Jolanta; Gómez-Ruano, Miguel-Ángel

2016-04-01

The purpose of this study was to evaluate the bilateral coordination in children and adolescents with visual impairments aged 7 to 18 years in comparison to their sighted peers. An additional objective was to identify the influence of sex and age on bilateral coordination. Seventy-five individuals with congenital severe visual impairment (40 girls and 35 boys) comprised the visually impaired group. The Sighted group comprised 139 youth without visual impairment. Subtest 4 of the Bruininks-Oseretsky Test of Motor Proficiency was administered to test bilateral coordination. To analyze the effect of the independent variables in the results obtained in the Subtest 4, four linear regression models were applied according to group and sex. The results indicated that severe visual impairment and lack of visual sensation had a negative effect on the development of participants' bilateral coordination, which however did not depend on sex or age. © The Author(s) 2016.

Developing a schedule to identify social communication difficulties and autism spectrum disorder in young children with visual impairment.

PubMed

Absoud, Michael; Parr, Jeremy R; Salt, Alison; Dale, Naomi

2011-03-01

Available observational tools used in the identification of social communication difficulties and diagnosis of autism spectrum disorder (ASD) rely partly on visual behaviours and therefore may not be valid in children with visual impairment. A pilot observational instrument, the Visual Impairment and Social Communication Schedule (VISS), was developed to aid in identifying social communication difficulties and ASD in young children with visual impairment affected by congenital disorders of the peripheral visual system (disorders of the globe, retina, and anterior optic nerve). The VISS was administered to 23 consecutive children (age range 1 y 9 mo-6 y 11 mo, mean 4 y 1 mo [SD 1.6]; 12 males, 11 females) with visual impairment (nine with severe and 14 with profound visual impairment). Item analysis was carried out by fit of the items to the Rasch model. Validity of the VISS was explored by comparison with the Childhood Autism Rating Scale (CARS) score, and the clinical ASD diagnosis (n=9). Correlation between the VISS and CARS total scores was highly significant (Spearman's rho=-0.89; p=0.01). Below threshold rating on the VISS (score of 35) showed good agreement with the clinical ASD diagnosis (sensitivity 89%, specificity 100%). This preliminary study shows the VISS to be a promising schedule to aid the identification of ASD in young children with visual impairment. © The Authors. Journal compilation © Mac Keith Press 2010.

Prevalence of eye disease and visual impairment in Île de la Gonave, Haïti.

PubMed

Tousignant, B; Brûlé, J

2017-08-01

Epidemiological data describing the prevalence of blindness and visual impairment in Haiti are sparse. The Haitian National Committee for the Prevention of Blindness (CNPC) estimates the prevalence of blindness at 1 %. Other regional data estimate moderate and severe visual impairment at 5% and 22%, respectively. IRIS Mundial (IM) is a non-governmental organization collaborating with the CNPC to develop eye care infrastructure in Haiti. To estimate the prevalence and causes of blindness and visual impairment on the Haitian island of Gonâve, to assist in planning of relevant eye care infrastructure. Results from eye exams carried out by a team from IM in January 2013 have been compiled and analyzed. In all, 1724 patients were examined (38% men, 62% women). In the best eye, 87% of patients had visual acuity, 6% had moderate visual impairment, and 7% had severe visual impairment. Moreover, 1% of patients had high myopia, 1% high hyperopia, 1% high astigmatism, and 32% were presbyopic. Clinically significant binocular cataracts were found in 1.5 % of patients, while 2 % were diagnosed with probable glaucoma. Our data give a glimpse of the prevalence of visual impairment and ocular disease on Gonâve Island in Haiti. Uncorrected refractive error, cataracts, and glaucoma are confirmed as prevalent conditions in this population and their presence should guide the planning of relevant eye care interventions.

New Systematic Review Methodology for Visual Impairment and Blindness for the 2010 Global Burden of Disease Study

PubMed Central

Bourne, Rupert; Price, Holly; Taylor, Hugh; Leasher, Janet; Keeffe, Jill; Glanville, Julie; Sieving, Pamela C; Khairallah, Moncef; Wong, Tien Yin; Zheng, Yingfeng; Mathew, Anu; Katiyar, Suchitra; Mascarenhas, Maya; Stevens, Gretchen A; Resnikoff, Serge; Gichuhi, Stephen; Naidoo, Kovin; Wallace, Diane; Kymes, Steven; Peters, Colleen; Pesudovs, Konrad; Braithwaite, Tasanee; Limburg, Hans

2014-01-01

Purpose To describe a systematic review of population-based prevalence studies of visual impairment (VI) and blindness worldwide over the past 32 years that informs the Global Burden of Diseases, Injuries and Risk Factors Study. Methods A systematic review (Stage 1) of medical literature from 1 January 1980 to 31 January 2012 identified indexed articles containing data on incidence, prevalence and causes of blindness and VI. Only cross-sectional population-based representative studies were selected from which to extract data for a database of age- and sex-specific data of prevalence of 4 distance and one near visual loss categories (presenting and best-corrected). Unpublished data and data from studies using ‘rapid assessment’ methodology were later added (Stage 2). Results Stage 1 identified 14,908 references, of which 204 articles met the inclusion criteria. Stage 2 added unpublished data from 44 ‘rapid assessment studies’ and 4 other surveys. This resulted in a final dataset of 252 articles of 243 studies, of which 238 (98%) reported distance vision loss categories. Thirty-seven studies of the final dataset reported prevalence of mild VI and 4 reported near vision impairment. Conclusion We report a comprehensive systematic review of over 30 years of VI/blindness studies. While there has been an increase in population-based studies conducted in the 2000’s compared to previous decades; there is limited information from certain regions (eg. Central Africa and Central and Eastern Europe, and the Caribbean and Latin America), younger age groups and minimal data regarding prevalence of near vision and mild distance visual impairment. PMID:23350553

Making memories: the development of long-term visual knowledge in children with visual agnosia.

PubMed

Metitieri, Tiziana; Barba, Carmen; Pellacani, Simona; Viggiano, Maria Pia; Guerrini, Renzo

2013-01-01

There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2  years and 3.7  years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

PubMed Central

Barba, Carmen; Pellacani, Simona; Viggiano, Maria Pia; Guerrini, Renzo

2013-01-01

There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2 years and 3.7 years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment. PMID:24319599

Sexual Health Education for Children with Visual Impairments: Talking about Sex Is Not Enough

ERIC Educational Resources Information Center

Krupa, Chelsea; Esmail, Shaniff

2010-01-01

This study investigated problems that children with visual impairments experience with sexual health education. The participants identified themes that affected their knowledge of sexual health and the need for sexual health education. Strategies that address sexual health issues for individuals with visual impairments are described.

Statistics on Children with Visual Impairments.

ERIC Educational Resources Information Center

Viisola, Michelle

This report summarizes statistical data relating to children with visual impairments, including incidence, causes, and education. Data include: (1) prevalence estimates that indicate 1 percent of persons under the age of 18 in the United States have a visual impairment that cannot be corrected with glasses; (2) the leading cause of childhood…

Identity Development in German Adolescents with and without Visual Impairments

ERIC Educational Resources Information Center

Pinquart, Martin; Pfeiffer, Jens P.

2013-01-01

Introduction: The study reported here assessed the exploration of identity and commitment to an identity in German adolescents with and without visual impairments. Methods: In total, 178 adolescents with visual impairments (blindness or low vision) and 526 sighted adolescents completed the Ego Identity Process Questionnaire. Results: The levels of…

Experiences of Students with Visual Impairments in Canadian Higher Education

ERIC Educational Resources Information Center

Reed, Maureen; Curtis, Kathryn

2012-01-01

Introduction: This article presents a study of the higher education experiences of students with visual impairments in Canada. Methods: Students with visual impairments and the staff members of disability programs were surveyed and interviewed regarding the students' experiences in entering higher education and completing their higher education…

The Research Priorities of People with Visual Impairments in the Netherlands

ERIC Educational Resources Information Center

Schölvinck, Anne-Floor M.; Pittens, Carina A. C. M.; Broerse, Jacqueline E. W.

2017-01-01

Introduction: Despite the relatively high prevalence and challenges of visual impairments, limited funding is available for ophthalmologic research in the Netherlands. The research needs of people with visual impairments could aid the ophthalmological research community to optimally distribute research resources. The objective of the study…

Self-Defense Training for Visually Impaired Women.

ERIC Educational Resources Information Center

Pava, W. S.; And Others

1991-01-01

This article describes the development and pilot testing of a curriculum to teach rape prevention and self-defense skills to visually impaired women. As a result of the course, five visually impaired women improved their physical self-defense skills, self-confidence, and problem-solving ability in hypothetically dangerous situations. (Author/DB)

Science Activities for the Visually Impaired: Developing a Model.

ERIC Educational Resources Information Center

DeLucchi, Linda; And Others

1980-01-01

Science activities for the visually impaired (SAVI) introduces blind and visually impaired children (9 to 12 years old) to physical and life sciences in a multisensory way. Evolution of SAVI activities involves exploration, local trials, and national trials. SAVI project materials can help integrate handicapped children into the mainstream through…

Parents' Perceptions of Physical Activity for Their Children with Visual Impairments

ERIC Educational Resources Information Center

Perkins, Kara; Columna, Luis; Lieberman, Lauren; Bailey, JoEllen

2013-01-01

Introduction: Ongoing communication with parents and the acknowledgment of their preferences and expectations are crucial to promote the participation of physical activity by children with visual impairments. Purpose: The study presented here explored parents' perceptions of physical activity for their children with visual impairments and explored…

Recess for Students with Visual Impairments

ERIC Educational Resources Information Center

Lucas, Matthew D.

2010-01-01

During recess, the participation of a student with visual impairments in terms of movement can often be both challenging and rewarding for the student and general education teacher. This paper will address common characteristics of students with visual impairments and present basic solutions to improve the participation of these students in the…

Early Childhood Special Education for Children with Visual Impairments: Problems and Solutions

ERIC Educational Resources Information Center

Kesiktas, A. Dolunay

2009-01-01

Studies showing developmental delays in infants and children with visual impairments have triggered early childhood special education studies for this population. Early childhood special education guidelines for visually impaired infants and children range from individualized services to personnel preparation issues while all display certain…

Food Preparation: An Instructional Package with Adaptations for Visually Impaired Individuals.

ERIC Educational Resources Information Center

Crawford, Glinda B.; And Others

This instructional package, developed for the home economics teacher of mainstreamed visually impaired students, provides food preparation lesson plans appropriate for the junior high level. First, teacher guidelines are given, including characteristics of the visually impaired, orienting such students to the classroom, orienting class members to…

Alternative Format Preferences among Secondary School Visually Impaired Students in Nigeria

ERIC Educational Resources Information Center

Adetoro, 'Niran

2012-01-01

Persons with visual impairment have consistently shown a preference for one alternative reading format over another, often because of factors outside their control. This study adopted survey research design to investigate alternative format preferences among secondary school visually impaired students, focusing on Southwestern Nigeria. Using total…

Youth with Visual Impairments: Experiences in General Physical Education

ERIC Educational Resources Information Center

Lieberman, Lauren J.; Robinson, Barbara L.; Rollheiser, Heidi

2006-01-01

The rapid increase in the number of students with visual impairments currently being educated in inclusive general physical education makes it important that physical education instructors know how best to serve them. Assessment of the experiences of students with visual impairments during general physical education classes, knowledge of students'…

The Physical Environment and the Visually Impaired.

ERIC Educational Resources Information Center

Braf, Per-Gunnar

Reported are results of a project carried out at the Swedish Institute for the Handicapped to determine needs of the visually impaired in the planning and adaptation of buildings and other forms of physical environment. Chapter 1 considers implications of impaired vision and includes definitions, statistics, and problems of the visually impaired…

Association between Visual Impairment and Low Vision and Sleep Duration and Quality among Older Adults in South Africa.

PubMed

Peltzer, Karl; Phaswana-Mafuya, Nancy

2017-07-19

This study aims to estimate the association between visual impairment and low vision and sleep duration and poor sleep quality in a national sample of older adults in South Africa. A national population-based cross-sectional Study of Global Ageing and Adults Health (SAGE) wave 1 was conducted in 2008 with a sample of 3840 individuals aged 50 years or older in South Africa. The interviewer-administered questionnaire assessed socio-demographic characteristics, health variables, sleep duration, quality, visual impairment, and vision. Results indicate that 10.0% of the sample reported short sleep duration (≤5 h), 46.6% long sleep (≥9 h), 9.3% poor sleep quality, 8.4% self-reported and visual impairment (near and/or far vision); and 43.2% measured low vision (near and/or far vision) (0.01-0.25 decimal) and 7.5% low vision (0.01-0.125 decimal). In fully adjusted logistic regression models, self-reported visual impairment was associated with short sleep duration and poor sleep quality, separately and together. Low vision was only associated with long sleep duration and poor sleep quality in unadjusted models. Self-reported visual impairment was related to both short sleep duration and poor sleep quality. Population data on sleep patterns may want to include visual impairment measures.

Effect of Visual Impairment on Physical and Cognitive Function in Old Age: Findings of a Population-Based Prospective Cohort Study in Germany.

PubMed

Hajek, André; Brettschneider, Christian; Lühmann, Dagmar; Eisele, Marion; Mamone, Silke; Wiese, Birgitt; Weyerer, Siegfried; Werle, Jochen; Pentzek, Michael; Fuchs, Angela; Riedel-Heller, Steffi G; Luck, Tobias; Bickel, Horst; Weeg, Dagmar; Koppara, Alexander; Wagner, Michael; Scherer, Martin; Maier, Wolfgang; König, Hans-Helmut

2016-11-01

To examine how visual impairment affects physical and cognitive function in old age. A longitudinal population-based prospective cohort study. General practitioner offices at six study centers in Germany. They were observed every 1.5 years over four waves. Individuals aged 77-101 at follow-up Wave 2 (N = 2,394). Physical and cognitive function were assessed using an adapted scale that had been previously developed, and visual impairment was rated on a Likert scale (none, mild, severe or profound). Adjusting for sociodemographic factors and comorbidity, linear fixed-effects regression showed that the onset of severe visual impairment was associated with a decline in physical function score in the total sample (β = -0.15, P = .01) and in women (β = -.15, P = .03). Moreover, the onset of severe visual impairment was associated with decline in cognitive function score in the total sample (β = -0.38, P < .001) and in women (β = -0.38, P < .001) and men (β = -0.37, P = .001). Visual impairment affects physical and cognitive function in old age. Interventional strategies to postpone visual impairment may contribute to maintaining physical and cognitive function. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Quantitative Postural Analysis of Children With Congenital Visual Impairment.

PubMed

de Pádua, Michelle; Sauer, Juliana F; João, Silvia M A

2018-01-01

The aim of this study was to compare the postural alignment of children with visual impairment with that of children without visual impairment. The sample studied was 74 children of both sexes ages 5 to 12 years. Of these, 34 had visual impairment and 40 were control children. Digital photos from the standing position were used to analyze posture. Postural variables, such as tilt of the head, shoulder position, scapula position, lateral deviation of the spine, ankle position in the frontal plane and head posture, angle of thoracic kyphosis, angle of lumbar lordosis, pelvis position, and knee position in the frontal and sagittal planes, were measured with the Postural Assessment Software 0.63, version 36 (SAPO, São Paulo, Brazil), with markers placed in predetermined bony landmarks. The main results of this study showed that children with visual impairment have increased head tilt (P < .001), shoulder deviation in frontal plane (P = .004), lateral deviation of the spine (P < .001), changes in scapula position (P = .012), higher thoracic kyphosis (P = .004), and lower lumbar lordosis (P < .001). Visual impairment influences postural alignment. Children with visual impairment had increased head tilt, uneven shoulders, greater lateral deviation of the spine, thoracic kyphosis, lower lumbar lordosis, and more severe valgus deformities on knees. Copyright © 2017. Published by Elsevier Inc.

Refractive errors.

PubMed

Schiefer, Ulrich; Kraus, Christina; Baumbach, Peter; Ungewiß, Judith; Michels, Ralf

2016-10-14

All over the world, refractive errors are among the most frequently occuring treatable distur - bances of visual function. Ametropias have a prevalence of nearly 70% among adults in Germany and are thus of great epidemiologic and socio-economic relevance. In the light of their own clinical experience, the authors review pertinent articles retrieved by a selective literature search employing the terms "ametropia, "anisometropia," "refraction," "visual acuity," and epidemiology." In 2011, only 31% of persons over age 16 in Germany did not use any kind of visual aid; 63.4% wore eyeglasses and 5.3% wore contact lenses. Refractive errors were the most common reason for consulting an ophthalmologist, accounting for 21.1% of all outpatient visits. A pinhole aperture (stenopeic slit) is a suitable instrument for the basic diagnostic evaluation of impaired visual function due to optical factors. Spherical refractive errors (myopia and hyperopia), cylindrical refractive errors (astigmatism), unequal refractive errors in the two eyes (anisometropia), and the typical optical disturbance of old age (presbyopia) cause specific functional limitations and can be detected by a physician who does not need to be an ophthalmologist. Simple functional tests can be used in everyday clinical practice to determine quickly, easily, and safely whether the patient is suffering from a benign and easily correctable type of visual impairment, or whether there are other, more serious underlying causes.

The Effects of Training on a Young Child with Cortical Visual Impairment: An Exploratory Study.

ERIC Educational Resources Information Center

Lueck, Amanda Hall; Dornbusch, Helen; Hart, Jeri

1999-01-01

This exploratory study investigated the effects of the components of visual environmental management, visual skills training, and visually dependent task training on the performance of visual behaviors of a toddler with multiple disabilities including cortical visual impairment. Training components were implemented by the mother during daily…

Food shopping, sensory determinants of food choice and meal preparation by visually impaired people. Obstacles and expectations in daily food experiences.

PubMed

Kostyra, Eliza; Żakowska-Biemans, Sylwia; Śniegocka, Katarzyna; Piotrowska, Anna

2017-06-01

The number of visually impaired and blind people is rising worldwide due to ageing of the global population, but research regarding the impact of visual impairment on the ability of a person to choose food and to prepare meals is scarce. The aim of this study was threefold: to investigate factors determining the choices of food products in people with various levels of impaired vision; to identify obstacles they face while purchasing food, preparing meals and eating out; and to determine what would help them in the areas of food shopping and meal preparation. The data was collected from 250 blind and visually impaired subjects, recruited with the support of the National Association of the Blind. The study revealed that majority of the visually impaired make food purchases at a supermarket or local grocery and they tend to favour shopping for food via the Internet. Direct sale channels like farmers markets were rarely used by the visually impaired. The most frequently mentioned factors that facilitated their food shopping decisions were the assistance of salespersons, product labelling in Braille, scanners that enable the reading of labels and a permanent place for products on the shop shelves. Meal preparation, particularly peeling, slicing and frying, posed many challenges to the visually impaired. More than half of the respondents ate meals outside the home, mainly with family or friends. The helpfulness of the staff and a menu in Braille were crucial for them to have a positive dining out experience. The results of the study provide valuable insights into the food choices and eating experiences of visually impaired people, and also suggest some practical implications to improve their independence and quality of life. Copyright © 2017 Elsevier Ltd. All rights reserved.

Toward an improved haptic zooming algorithm for graphical information accessed by individuals who are blind and visually impaired.

PubMed

Rastogi, Ravi; Pawluk, Dianne T V

2013-01-01

An increasing amount of information content used in school, work, and everyday living is presented in graphical form. Unfortunately, it is difficult for people who are blind or visually impaired to access this information, especially when many diagrams are needed. One problem is that details, even in relatively simple visual diagrams, can be very difficult to perceive using touch. With manually created tactile diagrams, these details are often presented in separate diagrams which must be selected from among others. Being able to actively zoom in on an area of a single diagram so that the details can be presented at a reasonable size for exploration purposes seems a simpler approach for the user. However, directly using visual zooming methods have some limitations when used haptically. Therefore, a new zooming method is proposed to avoid these pitfalls. A preliminary experiment was performed to examine the usefulness of the algorithm compared to not using zooming. The results showed that the number of correct responses improved with the developed zooming algorithm and participants found it to be more usable than not using zooming for exploration of a floor map.

Optical transmission testing based on asynchronous sampling techniques: images analysis containing chromatic dispersion using convolutional neural network

NASA Astrophysics Data System (ADS)

Mrozek, T.; Perlicki, K.; Tajmajer, T.; Wasilewski, P.

2017-08-01

The article presents an image analysis method, obtained from an asynchronous delay tap sampling (ADTS) technique, which is used for simultaneous monitoring of various impairments occurring in the physical layer of the optical network. The ADTS method enables the visualization of the optical signal in the form of characteristics (so called phase portraits) that change their shape under the influence of impairments such as chromatic dispersion, polarization mode dispersion and ASE noise. Using this method, a simulation model was built with OptSim 4.0. After the simulation study, data were obtained in the form of images that were further analyzed using the convolutional neural network algorithm. The main goal of the study was to train a convolutional neural network to recognize the selected impairment (distortion); then to test its accuracy and estimate the impairment for the selected set of test images. The input data consisted of processed binary images in the form of two-dimensional matrices, with the position of the pixel. This article focuses only on the analysis of images containing chromatic dispersion.

Global Estimates on the Number of People Blind or Visually Impaired by Diabetic Retinopathy: A Meta-analysis From 1990 to 2010.

PubMed

Leasher, Janet L; Bourne, Rupert R A; Flaxman, Seth R; Jonas, Jost B; Keeffe, Jill; Naidoo, Kovin; Pesudovs, Konrad; Price, Holly; White, Richard A; Wong, Tien Y; Resnikoff, Serge; Taylor, Hugh R

2016-09-01

To estimate global and regional trends from 1990 to 2010 of the prevalence and number of persons visually impaired specifically by diabetic retinopathy (DR), as a complication of the precipitous trends in global diabetes, is fundamental for health planning purposes. The meta-analysis of published population studies from 1990 to 2012 for the Global Burden of Disease Study 2010 (GBD) yielded estimated global regional trends in DR among other causes of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60). Globally in 2010, out of overall 32.4 million blind and 191 million visually impaired people, 0.8 million were blind and 3.7 million were visually impaired because of DR, with an alarming increase of 27% and 64%, respectively, spanning the two decades from 1990 to 2010. DR accounted for 2.6% of all blindness in 2010 and 1.9% of all MSVI worldwide, increasing from 2.1% and 1.3%, respectively, in 1990. These figures were lower in regions with younger populations (<2% in East and Southeast Asia and Oceania) than in high-income regions (North America, Western Europe, and Australasia) with relatively aging populations (>4%). The number of persons with visual impairment due to DR worldwide is rising and represents an increasing proportion of all blindness/MSVI causes. Age-standardized prevalence of DR-related blindness/MSVI was higher in sub-Saharan Africa and South Asia. One out of 39 blind people had blindness due to DR, and 1 out of 52 visually impaired people had visual impairment due to DR. © 2016 by the American Diabetes Association.

Prenatal exposure to polychlorinated biphenyls: a neuropsychologic analysis.

PubMed

Boucher, Olivier; Muckle, Gina; Bastien, Célyne H

2009-01-01

A large body of literature documents the effects of prenatal exposure to polychlorinated biphenyls (PCBs) on cognitive development of children. Despite this fact, no integrative synthesis has been published yet to identify the cognitive functions that are particularly affected. Our aim is to review this literature in an attempt to identify the cognitive profile associated with prenatal PCB exposure. Studies were identified by searching the PubMed database for articles published before June 2008. We reviewed data from nine prospective longitudinal birth cohorts for different aspects of cognition. Associations between indicators of prenatal PCB exposure and performance on cognitive tasks reported in the selected studies are summarized and classified as general cognitive abilities, verbal or visual-spatial skills, memory, attention, and executive functions. The most consistent effects observed across studies are impaired executive functioning related to increased prenatal PCB exposure. Negative effects on processing speed, verbal abilities, and visual recognition memory are also reported by most studies. Converging results from different cohort studies in which exposure arises from different sources make it unlikely that co-exposure with another associated contaminant is responsible for the observed effects. Prenatal PCB exposure appears to be related to a relatively specific cognitive profile of impairments. Failure to assess functions that are specifically impaired may explain the absence of effects found in some studies. Our findings have implications in the selection of cognitive assessment methods in future studies.

Health-related quality of life among people aged ≥65 years with self-reported visual impairment: findings from the 2006-2010 behavioral risk factor surveillance system.

PubMed

Crews, John E; Chou, Chiu-Fang; Zhang, Xinzhi; Zack, Matthew M; Saaddine, Jinan B

2014-10-01

To examine the association between health-related quality of life (HRQoL) and visual impairment among people aged ≥65 years. We used cross-sectional data from the 2006-2010 Behavioral Risk Factor Surveillance System to examine six HRQoL measures: self-reported health, physically unhealthy days, mentally unhealthy days, activity limitation days, life satisfaction, and disability. Visual impairment was categorized as no, a little, and moderate/severe. We examined the association between self-reported visual impairment and HRQoL using logistic regression accounting for the survey's complex design. People with self-reported moderate/severe visual impairment had more frequent (≥14) physically unhealthy days, mentally unhealthy days, and activity limitation days in the last 30 days compared to those reporting a little or no visual impairment. After controlling for all covariates (age, sex, marital status, race/ethnicity, education, income, diabetes, heart disease, stroke, heart attack, body mass index, leisure time activity, smoking, and medical care cost concerns) and comparing to those with no self-reported visual impairment, people reporting a little visual impairment were more likely to have fair/poor health (odds ratio, OR, 1.2, 95% confidence interval, CI, 1.1-1.3), life dissatisfaction (OR 1.6, 95% CI 1.3-2.0), and disability (OR 1.5, 95% CI 1.3-1.6), and those with self-reported moderate/severe visual impairment had more fair/poor health (OR 1.8, 95% CI 1.6-2.0), life dissatisfaction (OR 2.3, 95% CI 1.8-2.9), and disability (OR 2.0, 95% CI 1.8-2.2). They also had more frequent physically unhealthy days (OR 1.9, 95% CI 1.7-2.1), mentally unhealthy days (OR 1.8, 95% CI 1.5-2.1), and activity limitations days (OR 1.9, 95% CI 1.6-2.2). Poor HRQoL is strongly associated with the severity of self-reported visual impairment among people aged ≥65 years.

Health-Related Quality of Life Among People Aged ≥65 Years with Self-reported Visual Impairment: Findings from the 2006–2010 Behavioral Risk Factor Surveillance System

PubMed Central

Crews, John E.; Chou, Chiu-Fang; Zhang, Xinzhi; Zack, Matthew M.; Saaddine, Jinan B.

2016-01-01

Purpose To examine the association between health-related quality of life (HRQoL) and visual impairment among people aged ≥65 years. Methods We used cross-sectional data from the 2006–2010 Behavioral Risk Factor Surveillance System to examine six HRQoL measures: self-reported health, physically unhealthy days, mentally unhealthy days, activity limitation days, life satisfaction, and disability. Visual impairment was categorized as no, a little, and moderate/severe. We examined the association between self-reported visual impairment and HRQoL using logistic regression accounting for the survey’s complex design. Results People with self-reported moderate/severe visual impairment had more frequent (≥14) physically unhealthy days, mentally unhealthy days, and activity limitation days in the last 30 days compared to those reporting a little or no visual impairment. After controlling for all covariates (age, sex, marital status, race/ethnicity, education, income, diabetes, heart disease, stroke, heart attack, body mass index, leisure time activity, smoking, and medical care cost concerns) and comparing to those with no self-reported visual impairment, people reporting a little visual impairment were more likely to have fair/poor health (odds ratio, OR, 1.2, 95% confidence interval, CI, 1.1–1.3), life dissatisfaction (OR 1.6, 95% CI 1.3–2.0), and disability (OR 1.5, 95% CI 1.3–1.6), and those with self-reported moderate/severe visual impairment had more fair/poor health (OR 1.8, 95% CI 1.6–2.0), life dissatisfaction (OR 2.3, 95% CI 1.8–2.9), and disability (OR 2.0, 95% CI 1.8–2.2). They also had more frequent physically unhealthy days (OR 1.9, 95% CI 1.7–2.1), mentally unhealthy days (OR 1.8, 95% CI 1.5–2.1), and activity limitations days (OR 1.9, 95% CI 1.6–2.2). Conclusion Poor HRQoL is strongly associated with the severity of self-reported visual impairment among people aged ≥65 years. PMID:24955821

Retraining moderately impaired stroke survivors in driving-related visual attention skills.

PubMed

Akinwuntan, Abiodun E; Devos, Hannes; Verheyden, Geert; Baten, Guido; Kiekens, Carlotte; Feys, Hilde; De Weerdt, Willy

2010-01-01

Visual inattention is a major cause of road accidents and is a problem commonly experienced after stroke. This study investigated the effects of 2 training programs on performance in the Useful Field of View (UFOV), a validated test of driving-related visual attention skills. Data from 69 first-ever, moderately impaired stroke survivors who participated in a randomized controlled trial (RCT) to determine the effects of simulator training on driving after stroke were analyzed. In addition to regular interventions at a rehabilitation center, participants received 15 hours of either simulator-based driving-related training or non-computer-based cognitive training over 5 weeks. Total percentage reduction in UFOV and performance in divided and selective attention and speed of processing subtests were documented at 6 to 9 weeks (pretraining), 11 to 15 weeks (posttraining), and 6 months post stroke (follow-up). Generalized estimating equation (GEE) model revealed neither group effects nor significant interaction effects of group with time in the UFOV total score and the 3 subtests. However, there were significant within-group improvements from pre- through posttraining to follow-up for all the UFOV parameters. Post-hoc GEE analysis revealed that most improvement in both groups occurred from pre- to posttraining. Both training programs significantly improved visual attention skills of moderately impaired stroke survivors after 15 hours of training and retention of benefit lasted up to 6 months after stroke. Neither of the training programs was better than the other.

Health Inequalities Associated with Post-Stroke Visual Impairment in the United Kingdom and Ireland: A Systematic Review

PubMed Central

Hanna, K. L.; Rowe, F. J.

2017-01-01

ABSTRACT The aim of this study was to report on the health inequalities facing stroke survivors with visual impairments as described in the current literature. A systemic review of the literature was conducted to investigate the potential health inequalities facing stroke survivors with subsequent visual impairments. A quality-of-evidence and risk-of-bias assessment was conducted for each of the included articles using the appropriate tool dependent on the type of article. Only four articles discussed health inequalities affecting stroke survivors with visual impairment specifically. A further 23 articles identified health inequalities after stroke, and 38 reported on health inequalities within the visually impaired UK or Irish population. Stroke survivors with visual impairment face inconsistency in eye care provision nationally, along with variability in the assessment and management of visual disorders. The subgroups identified as most at risk were females; black ethnicity; lower socioeconomic status; older age; and those with lower education attainment. The issue of inconsistent service provision for this population must be addressed in future research. Further research must be conducted in order to firmly establish whether or not stroke survivors are at risk of the aforementioned sociodemographic and economic inequalities. PMID:28512502

Pragmatic abilities in children with congenital visual impairment: an exploration of non-literal language and advanced theory of mind understanding.

PubMed

Pijnacker, Judith; Vervloed, Mathijs P J; Steenbergen, Bert

2012-11-01

Children with congenital visual impairment have been reported to be delayed in theory of mind development. So far, research focused on first-order theory of mind, and included mainly blind children, whereas the majority of visually impaired children is not totally blind. The present study set out to explore whether children with a broader range of congenital visual impairments have a delay in more advanced theory of mind understanding, in particular second-order theory of mind (i.e. awareness that other people have beliefs about beliefs) and non-literal language (e.g. irony or figure of speech). Twenty-four children with congenital visual impairment and 24 typically developing sighted children aged between 6 and 13 were included. All children were presented with a series of stories involving understanding of theory of mind and non-literal language. When compared with sighted children of similar age and verbal intelligence, performance of children with congenital visual impairment on advanced theory of mind and non-literal stories was alike. The ability to understand the motivations behind non-literal language was associated with age, verbal intelligence and theory of mind skills, but was not associated with visual ability.

Retinotopically specific reorganization of visual cortex for tactile pattern recognition

PubMed Central

Cheung, Sing-Hang; Fang, Fang; He, Sheng; Legge, Gordon E.

2009-01-01

Although previous studies have shown that Braille reading and other tactile-discrimination tasks activate the visual cortex of blind and sighted people [1–5], it is not known whether this kind of cross-modal reorganization is influenced by retinotopic organization. We have addressed this question by studying S, a visually impaired adult with the rare ability to read print visually and Braille by touch. S had normal visual development until age six years, and thereafter severe acuity reduction due to corneal opacification, but no evidence of visual-field loss. Functional magnetic resonance imaging (fMRI) revealed that, in S’s early visual areas, tactile information processing activated what would be the foveal representation for normally-sighted individuals, and visual information processing activated what would be the peripheral representation. Control experiments showed that this activation pattern was not due to visual imagery. S’s high-level visual areas which correspond to shape- and object-selective areas in normally-sighted individuals were activated by both visual and tactile stimuli. The retinotopically specific reorganization in early visual areas suggests an efficient redistribution of neural resources in the visual cortex. PMID:19361999

Developmental outcome, including setback, in young children with severe visual impairment.

PubMed

Dale, Naomi; Sonksen, Patricia

2002-09-01

This study retrospectively investigated the developmental perspective of 69 children (40 males, 29 females) with 'potentially simple' congenital disorders of the peripheral visual system: development was examined in the context of degree of visual impairment. Developmental and visual assessments were carried out at 10 to 16 months (Time 1) and 27 to 54 months of age (Time 2). Participants were grouped according to (1) visual status: profound visual impairment (PVI), severe visual impairment (SVI); (2) developmental status on the Reynell-Zinkin scales. A majority of the sample showed normal development on all subscales (62% Time 1, 57% Time 2). Those with PVI were more developmentally vulnerable than SVI with a greater incidence of (1) uneven developmental profile at Time 1 (48% PVI, 16% SVI); (2) global learning difficulties at Time 2 (37% PVI, 0% SVI); (3) delay on individual subscales at Time 2 (p<0.02 PVI versus SVI); (4) deceleration (verbal comprehension 74% PVI, 24% SVI, sensorimotor understanding 70% PVI, 27% SVI); and (5) severe developmental setback (33% PVI, 7% SVI). Risk factors of visual level, age, and sex for poor developmental outcome in infants with visual impairment were established.

Visual impairment and blindness due to macular diseases globally: a systematic review and meta-analysis.

PubMed

Jonas, Jost B; Bourne, Rupert R A; White, Richard A; Flaxman, Seth R; Keeffe, Jill; Leasher, Janet; Naidoo, Kovin; Pesudovs, Konrad; Price, Holly; Wong, Tien Y; Resnikoff, Serge; Taylor, Hugh R

2014-10-01

To estimate the number of people visually impaired or blind due to macular diseases except those caused by diabetic maculopathy. Meta-analysis. Based on the Global Burden of Disease Study 2010 and ongoing literature research, we examined how many people were affected by vision impairment (presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60) due to macular diseases, with diabetic maculopathy excluded. In 2010, of 32.4 million blind people and 191 million vision-impaired people, 2.1 million (95% uncertainty interval [UI]: 1.9, 2.7) people were blind, and 6.0 million (95% UI: 5.2, 8.1) million were visually impaired due to macular diseases. In 2010, macular diseases caused 6.6% (95% UI: 6.0, 7.9) of all blindness and 3.1% (95% UI: 2.7, 4.0) of all vision impairment, worldwide. These figures were lower in regions with young populations than in high-income regions. Between 1990 and 2010, the number of people who were blind or visually impaired due to macular diseases increased by 36%, or 0.6 million people (95% UI: 0.5, 0.8) and by 81%, or 2.7 million (95% UI: 2.6, 3.9) people, respectively, whereas the global population increased by 30%. Age-standardized global prevalence of macula-related blindness and vision impairment in adults 50 years of age and older decreased from 0.2% (95% UI: 0.2, 0.2) in 1990 to 0.1% (95% UI: 0.1, 0.2) in 2010 and remained unchanged from 0.4% (95% UI: 0.3, 0.5) to 0.4% (95% UI: 0.4, 0.6), respectively. In 2010, 2.1 million people were blind and 6.0 million people were visually impaired due to macular diseases, except those caused by diabetic maculopathy. Of every 15 blind people, 1 was blind due to macular disease, and of every 32 visually impaired people, 1 was visually impaired due to macular disease. Copyright © 2014 Elsevier Inc. All rights reserved.

Number of People Blind or Visually Impaired by Cataract Worldwide and in World Regions, 1990 to 2010.

PubMed

Khairallah, Moncef; Kahloun, Rim; Bourne, Rupert; Limburg, Hans; Flaxman, Seth R; Jonas, Jost B; Keeffe, Jill; Leasher, Janet; Naidoo, Kovin; Pesudovs, Konrad; Price, Holly; White, Richard A; Wong, Tien Y; Resnikoff, Serge; Taylor, Hugh R

2015-10-01

To estimate prevalence and number of people visually impaired or blind due to cataract. Based on the Global Burden of Diseases Study 2010 and ongoing literature research, we examined how many people were affected by moderate to severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60) due to cataract. In 2010, of overall 32.4 million blind and 191 million vision impaired, 10.8 million people were blind and 35.1 million were visually impaired due to cataract. Cataract caused worldwide 33.4% of all blindness in 2010, and 18.4% of all MSVI. These figures were lower in the high-income regions (<15%) and higher (>40%) in South and Southeast Asia and Oceania. From 1990 to 2010, the number of blind or visually impaired due to cataract decreased by 11.4% and by 20.2%, respectively; the age-standardized global prevalence of cataract-related blindness and MSVI reduced by 46% and 50%, respectively, and the worldwide crude prevalence of cataract-related blindness and MSVI reduced by 32% and 39%, respectively. The percentage of global blindness and MSVI caused by cataract decreased from 38.6% to 33.4%, and from 25.6% to 18.4%, respectively. This decrease took place in almost all world regions, except East Sub-Saharan Africa. In 2010, one in three blind people was blind due to cataract, and one of six visually impaired people was visually impaired due to cataract. Despite major improvements in terms of reduction of prevalence, cataract remains a major public health problem.

Evaluating and Stimulating Vision in the Multiply Impaired.

ERIC Educational Resources Information Center

Jose, Randall T.; And Others

1980-01-01

Techniques for evaluating the multiply impaired child's functional level of vision are described and a sequence of visual stimulation instruction for children with visual impairments is presented. (PHR)

More insight into the interplay of response selection and visual attention in dual-tasks: masked visual search and response selection are performed in parallel.

PubMed

Reimer, Christina B; Schubert, Torsten

2017-09-15

Both response selection and visual attention are limited in capacity. According to the central bottleneck model, the response selection processes of two tasks in a dual-task situation are performed sequentially. In conjunction search, visual attention is required to select the items and to bind their features (e.g., color and form), which results in a serial search process. Search time increases as items are added to the search display (i.e., set size effect). When the search display is masked, visual attention deployment is restricted to a brief period of time and target detection decreases as a function of set size. Here, we investigated whether response selection and visual attention (i.e., feature binding) rely on a common or on distinct capacity limitations. In four dual-task experiments, participants completed an auditory Task 1 and a conjunction search Task 2 that were presented with an experimentally modulated temporal interval between them (Stimulus Onset Asynchrony, SOA). In Experiment 1, Task 1 was a two-choice discrimination task and the conjunction search display was not masked. In Experiment 2, the response selection difficulty in Task 1 was increased to a four-choice discrimination and the search task was the same as in Experiment 1. We applied the locus-of-slack method in both experiments to analyze conjunction search time, that is, we compared the set size effects across SOAs. Similar set size effects across SOAs (i.e., additive effects of SOA and set size) would indicate sequential processing of response selection and visual attention. However, a significantly smaller set size effect at short SOA compared to long SOA (i.e., underadditive interaction of SOA and set size) would indicate parallel processing of response selection and visual attention. In both experiments, we found underadditive interactions of SOA and set size. In Experiments 3 and 4, the conjunction search display in Task 2 was masked. Task 1 was the same as in Experiments 1 and 2, respectively. In both experiments, the d' analysis revealed that response selection did not affect target detection. Overall, Experiments 1-4 indicated that neither the response selection difficulty in the auditory Task 1 (i.e., two-choice vs. four-choice) nor the type of presentation of the search display in Task 2 (i.e., not masked vs. masked) impaired parallel processing of response selection and conjunction search. We concluded that in general, response selection and visual attention (i.e., feature binding) rely on distinct capacity limitations.

Selecting Individualized Reading Material for Informal Assessment of Students with Visual Impairments

ERIC Educational Resources Information Center

Kennedy, Mary Ann Rhoads

2004-01-01

Testing materials for high school students whose reading is below grade level might not be age-appropriate or sufficiently motivating. The first step in finding appropriate material would be to talk with the student to learn his or her interests. To find age-appropriate material the author searched Internet resources and then used Microsoft Word…

An Alternative Option to Dedicated Braille Notetakers for People with Visual Impairments: Universal Technology for Better Access

ERIC Educational Resources Information Center

Hong, Sunggye

2012-01-01

Technology provides equal access to information and helps people with visual impairments to complete tasks more independently. Among various assistive technology options for people with visual impairments, braille notetakers have been considered the most significant because of their technological innovation. Braille notetakers allow users who are…

Who Is the Visually Impaired Child? MAVIS Sourcebook 1.

ERIC Educational Resources Information Center

Efron, Marvin

This booklet is the first in a series of six sourcebooks produced by Project MAVIS (Materials Adaptations for Visually Impaired Students in the Social Studies). Designed primarily for teachers, the booklet defines visual impairment and its causes, explains how to interpret a student's eye report, and reviews aspects of the overall educational plan…

Adaptive Behavior of Primary School Students with Visual Impairments: The Impact of Educational Settings

ERIC Educational Resources Information Center

Metsiou, Katerina; Papadopoulos, Konstantinos; Agaliotis, Ioannis

2011-01-01

This study explored the adaptive behavior of primary school students with visual impairments, as well as the impact of educational setting on their adaptive behavior. Instrumentation included an informal questionnaire and the Vineland Adaptive Behavior Scales. Participants were 36 primary school students with visual impairments. The educational…

Predictors of Employment Outcomes for People with Visual Impairment in Taiwan: The Contribution of Disability Employment Services

ERIC Educational Resources Information Center

Jang, Yuh; Wang, Yun-Tung; Lin, Meng-Hsiu; Shih, Kevin J.

2013-01-01

Introduction: We investigated the employment status and identified factors that may affect the employment outcomes of people with visual impairments in Taiwan. Methods: A retrospective, ex post facto design study was conducted. The sample included 313 visually impaired clients who commenced and "closed" (completed) disability employment…

Certification for Teachers of the Visually Impaired: A Rural Teacher Training Project.

ERIC Educational Resources Information Center

Tweto-Johnson, Linda

The goal of a 2-year vision teacher training project is to provide the coursework instruction and student teaching opportunities necessary for Oregon certification as teacher of the visually impaired. The program was designed in response to several conditions affecting services for visually impaired students living in seven eastern Oregon…

Motivation and Physical Activity in Adolescents with Visual Impairments

ERIC Educational Resources Information Center

Kozub, Francis M.

2006-01-01

It is found that individuals with visual impairments have levels of intrinsic and extrinsic motivation and amotivation that influence their use of free time and lead to adaptive or maladaptive outcomes. As such, inactive individuals with visual impairments, lacking motivation to engage in physical activity, become dependent members of society who…

Improving Empathy and Communication Skills of Visually Impaired Early Adolescents through a Psycho-Education Program

ERIC Educational Resources Information Center

Yildiz, Mehmet Ali; Duy, Baki

2013-01-01

The purpose of this study was to investigate the effectiveness of an interpersonal communication skills psycho-education program to improve empathy and communication skills of visually impaired adolescents. Participants of the study were sixteen early adolescents schooling in an elementary school for visually impaired youth in Diyarbakir. The…

Comparing the Effects of Congenital and Late Visual Impairments on Visuospatial Mental Abilities

ERIC Educational Resources Information Center

Monegato, Maura; Cattaneo, Zaira; Pece, Alfredo; Vecchi, Tomaso

2007-01-01

This study compared participants who were congenitally visually impaired and those who became visually impaired later in life in a spatial memory task. The latter showed less efficient visuospatial processes than did the former. However, these differences were of a quantitative nature only, indicating common cognitive mechanisms that can be…

eText, Mathematics, and Students with Visual Impairments: "What Teachers Need to Know"

ERIC Educational Resources Information Center

Bouck, Emily C.; Meyer, Nancy K.

2012-01-01

Mathematics is an important educational component for students with visual impairments, and technology to support the access to and success of students with visual impairments in mathematics is essential. However, little research exists. This particular paper explores one aspect of technology and mathematics education for students with visual…

Knowledge and Skills for Teachers of Students with Visual Impairments Supervising the Work of Paraeducators

ERIC Educational Resources Information Center

Lewis, Sandra; McKenzie, Amy R.

2009-01-01

Teachers of students with visual impairments and paraeducators who work with students with visual impairments were surveyed to determine if previous research related to the competencies needed by teachers who supervise paraeducators applied to this subset of special educators. Both groups confirmed the importance of the competencies, but…

Factors Related to Impaired Visual Orienting Behavior in Children with Intellectual Disabilities

ERIC Educational Resources Information Center

Boot, F. H.; Pel, J .J. M.; Evenhuis, H. M.; van der Steen, J.

2012-01-01

It is generally assumed that children with intellectual disabilities (ID) have an increased risk of impaired visual information processing due to brain damage or brain development disorder. So far little evidence has been presented to support this assumption. Abnormal visual orienting behavior is a sensitive tool to evaluate impaired visual…

AODA Training Experiences of Blindness and Visual Impairment Professionals

ERIC Educational Resources Information Center

Davis, S. J.; Koch, D. Shane; McKee, Marissa F.; Nelipovich, Michael

2009-01-01

Co-existing alcohol and other drug abuse (AODA) and blindness or visually impairment may complicate the delivery of rehabilitation services. Professionals working with individuals who are blind or visually impaired need to be aware of unique issues facing those with co-existing disabilities. This study sought to examine the AODA training needs,…

The Social Experiences of High School Students with Visual Impairments

ERIC Educational Resources Information Center

Jessup, Glenda; Bundy, Anita C.; Broom, Alex; Hancock, Nicola

2017-01-01

Introduction: This study explores the social experiences in high school of students with visual impairments. Methods: Experience sampling methodology was used to examine (a) how socially included students with visual impairments feel, (b) the internal qualities of their activities, and (c) the factors that influence a sense of inclusion. Twelve…

Pain and Injury Associated with Powerlifting Training in Visually Impaired Athletes.

ERIC Educational Resources Information Center

Haykowsky, Mark J.; Warburton, Darren E. R.

1999-01-01

This study assessed occurrence and level of pain and injury history associated with powerlifting training in 11 adults with visual impairments. Powerlifting training was associated with an elevated occurrence of pain in shoulders, elbows, lower back, and knee regions. Injury rate, however, was lower than for athletes without visual impairments.…

Information Technology and Transcription of Reading Materials for the Visually Impaired Persons in Nigeria

ERIC Educational Resources Information Center

Nkiko, Christopher; Atinmo, Morayo I.; Michael-Onuoha, Happiness Chijioke; Ilogho, Julie E.; Fagbohun, Michael O.; Ifeakachuku, Osinulu; Adetomiwa, Basiru; Usman, Kazeem Omeiza

2018-01-01

Studies have shown inadequate reading materials for the visually impaired in Nigeria. Information technology has greatly advanced the provision of information to the visually impaired in other industrialized climes. This study investigated the extent of application of information technology to the transcription of reading materials for the…

A Glance at Worldwide Employment of People with Visual Impairments.

ERIC Educational Resources Information Center

Wolffe, Karen E.; Spungin, Susan J.

2002-01-01

A survey of 75 countries investigated jobs performed by adults with visual impairments throughout the world. Although there is a greater diversity in the range of jobs in developed countries, people who are visually impaired do not have the same range of opportunities available to them as sighted people. (Contains references.) (CR)

Working with Visual Impairment in Nigeria: A Qualitative Look at Employment Status

ERIC Educational Resources Information Center

Wolffe, Karen E.; Ajuwon, Paul M.; Kelly, Stacy M.

2013-01-01

Introduction: This study presents the perceptions of employed individuals with visual impairments living in one of the world's most populous developing nations, Nigeria. Methods: The researchers developed a questionnaire that assessed personal and professional experiences among a sample of 172 adults with visual impairments living and working in…

Visual Impairment and Self-Esteem: What Makes a Difference?

ERIC Educational Resources Information Center

Bowen, Jayne

2010-01-01

This account follows on from the research report "Visual impairment and its impact on self-esteem" (Bowen, 2010) published in this journal. The original article reported the results of an investigation of self-esteem levels amongst a sample group of 60 children with visual impairment. Four children, whose self-esteem was measured as…

Some Issues Concerning Access to Information by Blind and Partially Sighted Pupils.

ERIC Educational Resources Information Center

Green, Christopher F.

This paper examines problems faced by visually-impaired secondary pupils in gaining access to information in print. The ever-increasing volume of information available inundates the sighted and is largely inaccessible in print format to the visually impaired. Important issues of availability for the visually impaired include whether information is…

Experiences of Individuals with Visual Impairments in Integrated Physical Education: A Retrospective Study

ERIC Educational Resources Information Center

Haegele, Justin A.; Zhu, Xihe

2017-01-01

Purpose: The purpose of this retrospective study was to examine the experiences of adults with visual impairments during school-based integrated physical education (PE). Method: An interpretative phenomenological analysis (IPA) research approach was used and 16 adults (ages 21-48 years; 10 women, 6 men) with visual impairments acted as…

Expanding Understanding of Emergent Literacy: Empirical Support for a New Framework

ERIC Educational Resources Information Center

Erickson, Karen A.; Hatton, Deborah

2007-01-01

Emergent literacy in young children with visual impairments is examined using a conceptual framework proposed by Senechal, LeFevre, Smith-Chant, and Colton (2001). The utility of this framework for young children with visual impairments is illustrated using data from a field study of preschool classes for children with visual impairments.…

Perspectives of Parents of Children Who Are Visually Impaired: Implications for the Field.

ERIC Educational Resources Information Center

Leyser, Yona; Hienze, Toni

2001-01-01

A study involving 130 parents of children with visual impairments found parents were generally supportive of mainstreaming, but many also identified a number of risks and problems with it. Their child's social isolation concerned parents, along with the general education teacher's lack of knowledge and experience with visual impairments. (Contains…

Toward an Understanding of Language Symptomatology of Visually-Impaired Children.

ERIC Educational Resources Information Center

Prizant, Barry M.

The paper examines theoretical issues regarding the symptomatology of echolalia in the language of visually impaired children. Literature on echolalia is reviewed from a variety of perspectives and clinical work and research with visual impairment and with autism is discussed. Problems of definition are cited, and explanations for occurrence of…

Development of Object Permanence in Visually Impaired Infants.

ERIC Educational Resources Information Center

Rogers, S. J.; Puchalski, C. B.

1988-01-01

Development of object permanence skills was examined longitudinally in 20 visually impaired infants (ages 4-25 months). Order of skill acquisition and span of time required to master skills paralleled that of sighted infants, but the visually impaired subjects were 8-12 months older than sighted counterparts when similar skills were acquired.…

The Use of Final-Letter Braille Contractions: A Case Study

ERIC Educational Resources Information Center

Tallon, Emily M.; Herzberg, Tina S.

2013-01-01

Louis Braille developed a six-dot braille code in the early 1800s, thus creating an effective way for persons who are visually impaired to communicate through reading and writing (Holbrook, D'Andrea, & Sanford, 2011). Students with visual impairments require braille instruction from teachers of students with visual impairments, who are responsible…

Adapting the Brief COPE for Chinese Adolescents with Visual Impairments

ERIC Educational Resources Information Center

Yuan, Wei; Zhang, Li-fang; Li, Bing

2017-01-01

Introduction: The present research pioneered the effort in assessing adolescents' coping with visual impairment through adapting the Brief COPE in an eastern context. The first study preliminarily explored the applicability of the Brief COPE to Chinese adolescent students with visual impairments. Based on the results, the Brief COPE was modified…

A Quantitative Analysis of the Work Experiences of Adults with Visual Impairments in Nigeria

ERIC Educational Resources Information Center

Wolffe, Karen E.; Ajuwon, Paul M.; Kelly, Stacy M.

2013-01-01

Introduction: Worldwide, people with visual impairments often struggle to gain employment. This study attempts to closely evaluate the work experiences of employed individuals with visual impairments living in one of the world's most populous developing nations, Nigeria. Methods: The researchers developed a questionnaire that assessed personal and…

Perceptions of Schooling, Pedagogy and Notation in the Lives of Visually-Impaired Musicians

ERIC Educational Resources Information Center

Baker, David; Green, Lucy

2016-01-01

This article discusses findings on schooling, pedagogy and notation in the life-experiences of amateur and professional visually-impaired musicians/music teachers, and the professional experiences of sighted music teachers who work with visually-impaired learners. The study formed part of a broader UK Arts and Humanities Research Council funded…

Daily Routines and Sleep Disorders in Visually Impaired Children.

ERIC Educational Resources Information Center

Troster, Heinrich; And Others

1996-01-01

Assessed sleep disorders in 265 visually impaired and 67 non-disabled 10- to 72-month olds. Found that infants with visual impairments had more difficulties in falling asleep and in sleeping through the night than nonhandicapped children. Also found a relationship between sleep disorders and the regularity of children's daily routine and…

Training Teachers of Visually Impaired Children in Rural Tennessee.

ERIC Educational Resources Information Center

Trent, S. D.

1992-01-01

A Tennessee program awards stipends to teachers to attend summer classes and a practicum and earn 18 hours of credit in education of children with visual impairments. The program requires that teachers have assurance from their superintendents that they will teach visually impaired students in their school systems after endorsement. (Author/JDD)

The Meaning of Physical Education and Sport among Elite Athletes with Visual Impairments

ERIC Educational Resources Information Center

Haegele, Justin A.; Zhu, Xihe; Davis, Summer

2017-01-01

The purpose of this phenomenological study was to examine the meaning that elite athletes with visual impairments ascribed to their school-based physical education (PE) and sport experiences. A convenience sample of four elite male goalball athletes with visual impairment voluntarily participated in the study. Data were collected through…

The online behavior of pupils with visual impairment: A preliminary report.

PubMed

Wrzesińska, Magdalena; Tabała, Klaudia; Stecz, Patryk

2016-10-01

Young people with special educational needs are also users of new media. The aim of the study was to determine whether pupils with visual impairment spend more time on Internet use than pupils without visual impairment and whether youngsters from the study group are engaged in behaviors which could increase risk of problematic Internet use. The study is based on a total of 191 pupils: a study group of 66 partially-sighted pupils and a control group comprised 125 pupils who do not have visual impairment. A self-report questionnaire was constructed for the needs of this study. Pupils with visual impairment spent significantly less time on Internet use than their peers from the reference groups. Twice as many pupils from the study group as controls reported no symptoms suggesting potentially problematic Internet use. In addition, the study group more frequently used online social networking services and e-mails or used the Internet for assignments. Little difference exists between students with visual impairment and those without with regard to Internet use. Copyright © 2016 Elsevier Inc. All rights reserved.

Visualizing without Vision at the Microscale: Students with Visual Impairments Explore Cells with Touch

ERIC Educational Resources Information Center

Jones, M. Gail; Minogue, James; Oppewal, Tom; Cook, Michelle P.; Broadwell, Bethany

2006-01-01

Science instruction is typically highly dependent on visual representations of scientific concepts that are communicated through textbooks, teacher presentations, and computer-based multimedia materials. Little is known about how students with visual impairments access and interpret these types of visually-dependent instructional materials. This…

Causes of blindness and visual impairment among students in integrated schools for the blind in Nepal.

PubMed

Shrestha, Jyoti Baba; Gnyawali, Subodh; Upadhyay, Madan Prasad

2012-12-01

To identify the causes of blindness and visual impairment among students in integrated schools for the blind in Nepal. A total of 778 students from all 67 integrated schools for the blind in Nepal were examined using the World Health Organization/Prevention of Blindness Eye Examination Record for Children with Blindness and Low Vision during the study period of 3 years. Among 831 students enrolled in the schools, 778 (93.6%) participated in the study. Mean age of students examined was 13.7 years, and the male to female ratio was 1.4:1. Among the students examined, 85.9% were blind, 10% had severe visual impairment and 4.1% were visually impaired. The cornea (22.8%) was the most common anatomical site of visual impairment, its most frequent cause being vitamin A deficiency, followed by the retina (18.4%) and lens (17.6%). Hereditary and childhood factors were responsible for visual loss in 27.9% and 22.0% of students, respectively. Etiology could not be determined in 46% of cases. Overall, 40.9% of students had avoidable causes of visual loss. Vision could be improved to a level better than 6/60 in 3.6% of students refracted. More than one third of students were visually impaired for potentially avoidable reasons, indicating lack of eye health awareness and eye care services in the community. The cause of visual impairment remained unknown in a large number of students, which indicates the need for introduction of modern diagnostic tools.

The Association of Health-Related Quality of Life with Severity of Visual Impairment among People Aged 40-64 Years: Findings from the 2006-2010 Behavioral Risk Factor Surveillance System.

PubMed

Crews, John E; Chou, Chiu-Fang; Zack, Matthew M; Zhang, Xinzhi; Bullard, Kai McKeever; Morse, Alan R; Saaddine, Jinan B

2016-06-01

To examine the association of health-related quality of life (HRQoL) with severity of visual impairment among people aged 40-64 years. We used cross-sectional data from the 2006-2010 Behavioral Risk Factor Surveillance System to examine six measures of HRQoL: self-reported health, physically unhealthy days, mentally unhealthy days, activity limitation days, life satisfaction, and disability. Visual impairment was categorized as no, a little, or moderate/severe. We examined the association between visual impairment and HRQoL using logistic regression accounting for the survey's complex design. Overall, 23.0% of the participants reported a little difficult seeing, while 16.8% reported moderate/severe difficulty seeing. People aged 40-64 years with moderate/severe visual impairment had more frequent (≥14) physically unhealthy days, mentally unhealthy days, and activity limitation days in the last 30 days, as well as greater life dissatisfaction, greater disability, and poorer health compared to people reporting no or a little visual impairment. After controlling for covariates (age, sex, marital status, race/ethnicity, education, income, state, year, health insurance, heart disease, stroke, heart attack, body mass index, leisure-time activity, smoking, and medical care costs), and compared to people with no visual impairment, those with moderate/severe visual impairment were more likely to have fair/poor health (odds ratio, OR, 2.01, 95% confidence interval, CI, 1.82-2.23), life dissatisfaction (OR 2.06, 95% CI 1.80-2.35), disability (OR 1.95, 95% CI 1.80-2.13), and frequent physically unhealthy days (OR 1.69, 95% CI 1.52-1.88), mentally unhealthy days (OR 1.84, 95% CI 1.66-2.05), and activity limitation days (OR 1.94, 95% CI 1.71-2.20; all p < 0.0001). Poor HRQoL was strongly associated with moderate/severe visual impairment among people aged 40-64 years.

Prevalence and determinants of visual impairment in Canada: cross-sectional data from the Canadian Longitudinal Study on Aging.

PubMed

Aljied, Rumaisa; Aubin, Marie-Josée; Buhrmann, Ralf; Sabeti, Saama; Freeman, Ellen E

2018-06-01

To determine the prevalence and determinants of visual impairment in Canada. Cross-sectional population-based study. 30,097 people in the Comprehensive Cohort of the Canadian Longitudinal Study on Aging METHODS: Inclusion criteria included being between the ages of 45 and 85 years old, community-dwelling, and living near one of the 11 data collection sites across 7 Canadian provinces. People were excluded if they were in an institution, living on a First Nations reserve, were a full-time member of the Canadian Armed Forces, did not speak French or English, or had cognitive impairment. Visual acuity was measured using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart while participants wore their usual prescription for distance, if any. Visual impairment was defined as presenting binocular acuity worse than 20/40. Of Canadian adults, 5.7% (95% CI 5.4-6.0) had visual impairment. A wide variation in the provincial prevalence of visual impairment was observed ranging from a low of 2.4% (95% CI 2.0-3.0) in Manitoba to a high of 10.9% (95% CI 9.6-12.2) in Newfoundland and Labrador. Factors associated with a higher odds of visual impairment included older age (odds ratio [OR] = 1.07, 95% CI 1.06-1.08), lower income (OR = 2.07 for those earning less than $20 000 per year, 95% CI 1.65-2.59), current smoking (OR = 1.52, 95% CI 1.25-1.85), type 2 diabetes (OR = 1.20, 95% CI 1.03-1.41), and memory problems (OR = 1.44, 95% CI 1.04-2.01). Refractive error was the leading cause of visual impairment. Older age, lower income, province, smoking, diabetes, and memory problems were associated with visual impairment. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

The needs of parents of children with visual impairment studying in mainstream schools in Hong Kong.

PubMed

Lee, Florence M Y; Tsang, Janice F K; Chui, Mandy M Y

2014-10-01

This study attempted to use a validated and standardised psychometric tool to identify the specific needs of parents of children with visual impairment studying in mainstream schools in Hong Kong. The second aim was to compare their needs with those of parents of mainstream school children without special education needs and parents having children with learning and behavioural problems. Cross-sectional survey. Mainstream schools in Hong Kong. Parents of 30 children with visual impairment who were studying in mainstream schools and attended assessment by optometrists at Child Assessment Service between May 2009 and June 2010 were recruited in the study (visual impairment group). Parents of 45 children with learning and behavioural problems recruited from two parent support groups (learning and behavioural problems group), and parents of 233 children without special education needs studying in mainstream schools recruited in a previous validation study on Service Needs Questionnaire (normal group) were used for comparison. Participants were invited to complete a self-administered Service Needs Questionnaire and a questionnaire on demographics of the children and their responding parents. The visual impairment group was asked additional questions about the ability of the child in coping and functioning in academic and recreational activities. Needs expressed by parents of the visual impairment group were significantly higher than those of parents of the normal group, and similar to those in the learning and behavioural problems group. Parents of children with visual impairment expressed more needs for future education and school support than resources for dealing with personal and family stress. Service needs of children with visual impairment and their families are high, particularly for future education and school support. More study on the various modes of accommodation for children with visual impairment and more collaborative work among different partners working in the field of rehabilitation will foster better service for these children and their families.

Are normally sighted, visually impaired, and blind pedestrians accurate and reliable at making street crossing decisions?

PubMed

Hassan, Shirin E

2012-05-04

The purpose of this study is to measure the accuracy and reliability of normally sighted, visually impaired, and blind pedestrians at making street crossing decisions using visual and/or auditory information. Using a 5-point rating scale, safety ratings for vehicular gaps of different durations were measured along a two-lane street of one-way traffic without a traffic signal. Safety ratings were collected from 12 normally sighted, 10 visually impaired, and 10 blind subjects for eight different gap times under three sensory conditions: (1) visual plus auditory information, (2) visual information only, and (3) auditory information only. Accuracy and reliability in street crossing decision-making were calculated for each subject under each sensory condition. We found that normally sighted and visually impaired pedestrians were accurate and reliable in their street crossing decision-making ability when using either vision plus hearing or vision only (P > 0.05). Under the hearing only condition, all subjects were reliable (P > 0.05) but inaccurate with their street crossing decisions (P < 0.05). Compared to either the normally sighted (P = 0.018) or visually impaired subjects (P = 0.019), blind subjects were the least accurate with their street crossing decisions under the hearing only condition. Our data suggested that visually impaired pedestrians can make accurate and reliable street crossing decisions like those of normally sighted pedestrians. When using auditory information only, all subjects significantly overestimated the vehicular gap time. Our finding that blind pedestrians performed significantly worse than either the normally sighted or visually impaired subjects under the hearing only condition suggested that they may benefit from training to improve their detection ability and/or interpretation of vehicular gap times.

Are Normally Sighted, Visually Impaired, and Blind Pedestrians Accurate and Reliable at Making Street Crossing Decisions?

PubMed Central

Hassan, Shirin E.

2012-01-01

Purpose. The purpose of this study is to measure the accuracy and reliability of normally sighted, visually impaired, and blind pedestrians at making street crossing decisions using visual and/or auditory information. Methods. Using a 5-point rating scale, safety ratings for vehicular gaps of different durations were measured along a two-lane street of one-way traffic without a traffic signal. Safety ratings were collected from 12 normally sighted, 10 visually impaired, and 10 blind subjects for eight different gap times under three sensory conditions: (1) visual plus auditory information, (2) visual information only, and (3) auditory information only. Accuracy and reliability in street crossing decision-making were calculated for each subject under each sensory condition. Results. We found that normally sighted and visually impaired pedestrians were accurate and reliable in their street crossing decision-making ability when using either vision plus hearing or vision only (P > 0.05). Under the hearing only condition, all subjects were reliable (P > 0.05) but inaccurate with their street crossing decisions (P < 0.05). Compared to either the normally sighted (P = 0.018) or visually impaired subjects (P = 0.019), blind subjects were the least accurate with their street crossing decisions under the hearing only condition. Conclusions. Our data suggested that visually impaired pedestrians can make accurate and reliable street crossing decisions like those of normally sighted pedestrians. When using auditory information only, all subjects significantly overestimated the vehicular gap time. Our finding that blind pedestrians performed significantly worse than either the normally sighted or visually impaired subjects under the hearing only condition suggested that they may benefit from training to improve their detection ability and/or interpretation of vehicular gap times. PMID:22427593

A comparison of dosing accuracy: visually impaired and sighted people using insulin pens.

PubMed

Williams, Ann S; Schnarrenberger, Patrick A

2010-05-01

In the United States, 18% of people with diagnosed diabetes have visual impairment. Insulin pens are widely used by both blind and sighted people. However, major manufacturers include a disclaimer in the instructions warning against use by visually impaired people, without giving a rationale. Published studies neither support nor refute the disclaimer. The purpose of this study was to compare accuracy of dosing with insulin pens between visually impaired and sighted people. Inclusion criteria were self-reported diabetes and inability (visually impaired group) or ability (sighted group) to read regular print. The sole exclusion criterion was inability to pass a brief test of decisional capacity. Each participant received standardized instructions for insulin pen use, either in recorded (visually impaired group) or in printed (sighted group) format, and delivered 10 systematically varied doses into an injection ball, which was weighed on a precision laboratory balance. No significant correlation with accuracy of insulin dosing was found for any of the analyzed variables: visual status, age, gender, years of having diabetes mellitus (DM), or treatment of DM with or without insulin. This study provided preliminary evidence of the safety of use of insulin pens by visually impaired people and raised questions about the validity of the disclaimer. Further study of the safety of use of insulin pens by blind people is needed. Inclusion of people with disabilities in research on technology intended for patient use would ensure that people with disabilities can benefit from new technology. (c) 2010 Diabetes Technology Society.

Blindness and Severe Visual Impairment in Pupils at Schools for the Blind in Burundi

PubMed Central

Ruhagaze, Patrick; Njuguna, Kahaki Kimani Margaret; Kandeke, Lévi; Courtright, Paul

2013-01-01

Purpose: To determine the causes of childhood blindness and severe visual impairment in pupils attending schools for the blind in Burundi in order to assist planning for services in the country. Materials and Methods: All pupils attending three schools for the blind in Burundi were examined. A modified WHO/PBL eye examination record form for children with blindness and low vision was used to record the findings. Data was analyzed for those who became blind or severely visually impaired before the age of 16 years. Results: Overall, 117 pupils who became visually impaired before 16 years of age were examined. Of these, 109 (93.2%) were blind or severely visually impaired. The major anatomical cause of blindness or severe visual impairment was cornea pathology/phthisis (23.9%), followed by lens pathology (18.3%), uveal lesions (14.7%) and optic nerve lesions (11.9%). In the majority of pupils with blindness or severe visual impairment, the underlying etiology of visual loss was unknown (74.3%). More than half of the pupils with lens related blindness had not had surgery; among those who had surgery, outcomes were generally poor. Conclusion: The causes identified indicate the importance of continuing preventive public health strategies, as well as the development of specialist pediatric ophthalmic services in the management of childhood blindness in Burundi. The geographic distribution of pupils at the schools for the blind indicates a need for community-based programs to identify and refer children in need of services. PMID:23580854

Blindness and severe visual impairment in pupils at schools for the blind in Burundi.

PubMed

Ruhagaze, Patrick; Njuguna, Kahaki Kimani Margaret; Kandeke, Lévi; Courtright, Paul

2013-01-01

To determine the causes of childhood blindness and severe visual impairment in pupils attending schools for the blind in Burundi in order to assist planning for services in the country. All pupils attending three schools for the blind in Burundi were examined. A modified WHO/PBL eye examination record form for children with blindness and low vision was used to record the findings. Data was analyzed for those who became blind or severely visually impaired before the age of 16 years. Overall, 117 pupils who became visually impaired before 16 years of age were examined. Of these, 109 (93.2%) were blind or severely visually impaired. The major anatomical cause of blindness or severe visual impairment was cornea pathology/phthisis (23.9%), followed by lens pathology (18.3%), uveal lesions (14.7%) and optic nerve lesions (11.9%). In the majority of pupils with blindness or severe visual impairment, the underlying etiology of visual loss was unknown (74.3%). More than half of the pupils with lens related blindness had not had surgery; among those who had surgery, outcomes were generally poor. The causes identified indicate the importance of continuing preventive public health strategies, as well as the development of specialist pediatric ophthalmic services in the management of childhood blindness in Burundi. The geographic distribution of pupils at the schools for the blind indicates a need for community-based programs to identify and refer children in need of services.

Visual Impairment Registry of Patients from North Kolkata, Eastern India: A Hospital-based Study.

PubMed

Bandyopadhyay, Sabyasachi; Bandyopadhyay, Samir Kumar; Biswas, Jaya; Saha Dutta Chowdhury, Mita; Dey, Asim Kumar; Chakrabarti, Asim

2018-01-01

To study the demographic profile, severity and causes of visual impairment among registered patients in a tertiary care hospital in north Kolkata, eastern India, and to assess the magnitude of under-registration in that population. This is a retrospective analytical study. A review of all visually impaired patients registered at our tertiary care hospital during a ten-year period from January 2005 to December 2014, which is entitled for certification of people of north Kolkata, eastern India (with a population denominator of 1.1 million), was performed. Overall, 2472 eyes of 1236 patients were analyzed in terms of demographic characteristics, cause of visual impairment, and percentage of visual disability as per the guidelines established by the government of India. Male patients (844, 68.28%; 95% confidence interval [CI], 65.69-70.87) registered more often than female patients (392; 31.72%, P = 0.0004). The registration rate for visual impairment was 11.24 per 100,000 per annum; this is not the true incidence rate, as both new patients and those visiting for renewal of certification were included in the study. Optic atrophy was the most common cause of visual impairment (384 eyes, 15.53%; 95% CI, 14.1-16.96). Commonest cause of visual impairment was optic atrophy followed by microphthalmos. Under-registration is a prevalent problem as the registration system is voluntary rather than mandatory, and female patients are more likely to be unregistered in this area.

Major depressive and anxiety disorders in visually impaired older adults.

PubMed

van der Aa, Hilde P A; Comijs, Hannie C; Penninx, Brenda W J H; van Rens, Ger H M B; van Nispen, Ruth M A

2015-01-20

We assessed the prevalence of subthreshold depression and anxiety, and major depressive, dysthymic, and anxiety disorders (panic disorder, agoraphobia, social phobia, and general anxiety disorder) in visually impaired older adults and compared these estimates with those of normally sighted peers. Cross-sectional data were analyzed based on telephone interviews with visually impaired older adults aged ≥ 60 years (n = 615) with a visual acuity of ≥ 0.30 logMAR (20/40 Snellen) in the best eye from outpatient low vision rehabilitation centers, and face-to-face interviews with community-dwelling normally sighted peers (n = 1232). To determine prevalence rates, the normally sighted population was weighted on sex and age to fit the visually impaired population. Logistic regression analyses were used to compare the populations and to correct for confounders. The prevalence of major depressive disorder (5.4%) and anxiety disorders (7.5%), as well as the prevalence of subthreshold depression (32.2%) and subthreshold anxiety (15.6%), were significantly higher in visually impaired older adults compared to their normally sighted peers (P < 0.05). Agoraphobia and social phobia were the most prevalent anxiety disorders in visually impaired older adults. This study shows that depression and anxiety are major public health problems in visually impaired older adults. Research on psychotherapeutic and psychopharmacologic interventions to improve depression and anxiety in this population is warranted. (http://www.trialregister.nl number, NTR3296.). Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

Individual Alpha Peak Frequency Predicts 10 Hz Flicker Effects on Selective Attention.

PubMed

Gulbinaite, Rasa; van Viegen, Tara; Wieling, Martijn; Cohen, Michael X; VanRullen, Rufin

2017-10-18

Rhythmic visual stimulation ("flicker") is primarily used to "tag" processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (∼10 Hz) oscillations during a selective visuospatial attention task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen flanker task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed-effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs low selective attention demands). Crucially, the effect of 10 Hz flicker on task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the task). Finally, the flicker effect on task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms. SIGNIFICANCE STATEMENT Here we provide novel evidence that the interaction between exogenous rhythmic visual stimulation and endogenous brain rhythms can have frequency-specific behavioral effects. We show that alpha-band (10 Hz) flicker impairs stimulus processing in a selective attention task when the stimulus flicker rate matches individual alpha peak frequency. The effect of sensory flicker on task performance was stronger when selective attention demands were high, and was stronger during stimulus processing and response selection compared with the prestimulus anticipatory period. These findings provide novel evidence that frequency-specific sensory flicker affects online attentional processing, and also demonstrate that the correspondence between exogenous and endogenous rhythms is an overlooked prerequisite when testing for frequency-specific cognitive effects of flicker. Copyright © 2017 the authors 0270-6474/17/3710173-12$15.00/0.

Leisure and health benefits among Korean adolescents with visual impairments.

PubMed

Kim, Junhyoung; Park, Se-Hyuk

2018-12-01

The purpose of the study was to explore health benefits through leisure engagement among Korean adolescents with visual impairments. Using semi-structured interviews, a total of 14 adolescents with visual impairments participated in this study. Two salient themes were captured as health benefits as a result of leisure engagement: psychological wellbeing and personal growth. The findings suggest that leisure provides a venue for the development of self-expression, leisure skills, perseverance, and positive affects. It also indicates that leisure can serve as a vehicle for promoting health and life satisfaction among Korean adolescents with visual impairments.

Boston Community Information System 1986 Experimental Test Results.

DTIC Science & Technology

1987-08-01

self -selected participants have a strong technical orientation and high educational achievement. In addition, five visually impaired people use the...group. The experimental test of the system was performed on a self -selected population of computer literate volunteers. In order to simplify the test...for fat respose .’ - 1041 OI haven’t used it yet.’ - 1046 ’No modem yet. New version installed 11/2/86.0 - 1047 ’Not yet tried. Wil do so moon.’ - 1061

Pituitary apoplexy.

PubMed

Bi, Wenya Linda; Dunn, Ian F; Laws, Edward R

2015-02-01

Pituitary apoplexy is a clinical syndrome of sudden headache and visual decline associated with acute hemorrhagic or ischemic change of an intrasellar mass, and comprises only a subset of hemorrhagic pituitary lesions. The most common presenting symptoms include headache, nausea, diminished visual acuity or visual field, ophthalmoplegia/paresis, and impaired mental status. Multiple risk factors have been reported, although the majority of cases have no identifiable precipitants. MRI is the most sensitive diagnostic modality, with specific imaging findings dependent on the timing post-hemorrhage. Early clinical suspicion is imperative to allow for corticosteroid replacement and hemodynamic stabilization when indicated. Transsphenoidal surgical decompression improves outcome in a majority of cases, although conservative management may be appropriate in select scenarios.

Saccade Generation by the Frontal Eye Fields in Rhesus Monkeys Is Separable from Visual Detection and Bottom-Up Attention Shift

PubMed Central

Lee, Kyoung-Min; Ahn, Kyung-Ha; Keller, Edward L.

2012-01-01

The frontal eye fields (FEF), originally identified as an oculomotor cortex, have also been implicated in perceptual functions, such as constructing a visual saliency map and shifting visual attention. Further dissecting the area’s role in the transformation from visual input to oculomotor command has been difficult because of spatial confounding between stimuli and responses and consequently between intermediate cognitive processes, such as attention shift and saccade preparation. Here we developed two tasks in which the visual stimulus and the saccade response were dissociated in space (the extended memory-guided saccade task), and bottom-up attention shift and saccade target selection were independent (the four-alternative delayed saccade task). Reversible inactivation of the FEF in rhesus monkeys disrupted, as expected, contralateral memory-guided saccades, but visual detection was demonstrated to be intact at the same field. Moreover, saccade behavior was impaired when a bottom-up shift of attention was not a prerequisite for saccade target selection, indicating that the inactivation effect was independent of the previously reported dysfunctions in bottom-up attention control. These findings underscore the motor aspect of the area’s functions, especially in situations where saccades are generated by internal cognitive processes, including visual short-term memory and long-term associative memory. PMID:22761923

Saccade generation by the frontal eye fields in rhesus monkeys is separable from visual detection and bottom-up attention shift.

PubMed

Lee, Kyoung-Min; Ahn, Kyung-Ha; Keller, Edward L

2012-01-01

The frontal eye fields (FEF), originally identified as an oculomotor cortex, have also been implicated in perceptual functions, such as constructing a visual saliency map and shifting visual attention. Further dissecting the area's role in the transformation from visual input to oculomotor command has been difficult because of spatial confounding between stimuli and responses and consequently between intermediate cognitive processes, such as attention shift and saccade preparation. Here we developed two tasks in which the visual stimulus and the saccade response were dissociated in space (the extended memory-guided saccade task), and bottom-up attention shift and saccade target selection were independent (the four-alternative delayed saccade task). Reversible inactivation of the FEF in rhesus monkeys disrupted, as expected, contralateral memory-guided saccades, but visual detection was demonstrated to be intact at the same field. Moreover, saccade behavior was impaired when a bottom-up shift of attention was not a prerequisite for saccade target selection, indicating that the inactivation effect was independent of the previously reported dysfunctions in bottom-up attention control. These findings underscore the motor aspect of the area's functions, especially in situations where saccades are generated by internal cognitive processes, including visual short-term memory and long-term associative memory.

Blindness and Visual Impairment Profile and Rapid Assessment of Avoidable Blindness in South East Asia: Analysis of New Data. 2017 APAO Holmes Lecture.

PubMed

Das, Taraprasad

2018-03-13

The International Agency for Prevention of Blindness (IAPB) South East Asia region (SEAR) that consists of 11 countries contains 26% of the world's population (1,761,000,000). In this region 12 million are blind and 78.5 million are visually impaired. This amounts to 30% of global blindness and 32% of global visual impairment. Rapid assessment of avoidable blindness (RAAB) survey analysis. RAAB, either a repeat or a first time survey, was completed in 8 countries in this decade (2010 onwards). These include Bangladesh, Bhutan, India, Indonesia, Maldives, Sri Lanka, Thailand, and Timor Leste. Cataract is the principal cause of blindness and severe visual impairment in all countries. Refractive error is the principal cause of moderate visual impairment in 4 countries: Bangladesh, India, Maldives, and Sri Lanka; cataract continues to be the principal cause of moderate visual impairment in 4 other countries: Bhutan, Indonesia, Thailand, and Timor Leste. Outcome of cataract surgery is suboptimal in the Maldives and Timor Leste. Rigorous focus is necessary to improve cataract surgery outcomes and correction of refractive error without neglecting the quality of care. At the same time allowances must be made for care of the emerging causes of visual impairment and blindness such as glaucoma and posterior segment disorders, particularly diabetic retinopathy. Copyright 2018 Asia-Pacific Academy of Ophthalmology.

Development of an Age Band on the ManuVis for 3-Year-Old Children with Visual Impairments.

PubMed

Reimer, A M; Barsingerhorn, A D; Overvelde, A; Nijhuis-Van der Sanden, M W G; Boonstra, F N; Cox, R F A

2017-08-01

To compare fine motor performance of 3-year-old children with visual impairment with peers having normal vision, to provide reference scores for 3-year-old children with visual impairment on the ManuVis, and to assess inter-rater reliability. 26 children with visual impairment (mean age: 3 years 7 months (SD 3 months); 17 boys) and 28 children with normal vision (mean age: 3 years 7 months (SD 4 months); 14 boys) participated in the study. The ManuVis age band for 3-year-old children comprised two one-handed tasks, two two-handed tasks, and a pre-writing task. Children with visual impairment needed more time on all tasks (p < .01) and performed the pre-writing task less accurately than children with normal vision (p < .001). Children aged 42-47 months performed significantly faster on two tasks and had better total scores than children aged 36-41 months (p < .05). Inter-rater reliability was excellent (Intra-class Correlation Coefficient = 0.96-0.99). The ManuVis age band for 3-year-old children is appropriate to assess fine motor skills, and is sensitive to differences between children with visual impairment and normal vision and between half-year age groups. Reference scores are provided for 3-year-old children with visual impairment to identify delayed fine motor development.

Influence of uncorrected refractive error and unmet refractive error on visual impairment in a Brazilian population.

PubMed

Ferraz, Fabio H; Corrente, José E; Opromolla, Paula; Schellini, Silvana A

2014-06-25

The World Health Organization (WHO) definitions of blindness and visual impairment are widely based on best-corrected visual acuity excluding uncorrected refractive errors (URE) as a visual impairment cause. Recently, URE was included as a cause of visual impairment, thus emphasizing the burden of visual impairment due to refractive error (RE) worldwide is substantially higher. The purpose of the present study is to determine the reversal of visual impairment and blindness in the population correcting RE and possible associations between RE and individual characteristics. A cross-sectional study was conducted in nine counties of the western region of state of São Paulo, using systematic and random sampling of households between March 2004 and July 2005. Individuals aged more than 1 year old were included and were evaluated for demographic data, eye complaints, history, and eye exam, including no corrected visual acuity (NCVA), best corrected vision acuity (BCVA), automatic and manual refractive examination. The definition adopted for URE was applied to individuals with NCVA > 0.15 logMAR and BCVA ≤ 0.15 logMAR after refractive correction and unmet refractive error (UREN), individuals who had visual impairment or blindness (NCVA > 0.5 logMAR) and BCVA ≤ 0.5 logMAR after optical correction. A total of 70.2% of subjects had normal NCVA. URE was detected in 13.8%. Prevalence of 4.6% of optically reversible low vision and 1.8% of blindness reversible by optical correction were found. UREN was detected in 6.5% of individuals, more frequently observed in women over the age of 50 and in higher RE carriers. Visual impairment related to eye diseases is not reversible with spectacles. Using multivariate analysis, associations between URE and UREN with regard to sex, age and RE was observed. RE is an important cause of reversible blindness and low vision in the Brazilian population.

Influence of uncorrected refractive error and unmet refractive error on visual impairment in a Brazilian population

PubMed Central

2014-01-01

Background The World Health Organization (WHO) definitions of blindness and visual impairment are widely based on best-corrected visual acuity excluding uncorrected refractive errors (URE) as a visual impairment cause. Recently, URE was included as a cause of visual impairment, thus emphasizing the burden of visual impairment due to refractive error (RE) worldwide is substantially higher. The purpose of the present study is to determine the reversal of visual impairment and blindness in the population correcting RE and possible associations between RE and individual characteristics. Methods A cross-sectional study was conducted in nine counties of the western region of state of São Paulo, using systematic and random sampling of households between March 2004 and July 2005. Individuals aged more than 1 year old were included and were evaluated for demographic data, eye complaints, history, and eye exam, including no corrected visual acuity (NCVA), best corrected vision acuity (BCVA), automatic and manual refractive examination. The definition adopted for URE was applied to individuals with NCVA > 0.15 logMAR and BCVA ≤ 0.15 logMAR after refractive correction and unmet refractive error (UREN), individuals who had visual impairment or blindness (NCVA > 0.5 logMAR) and BCVA ≤ 0.5 logMAR after optical correction. Results A total of 70.2% of subjects had normal NCVA. URE was detected in 13.8%. Prevalence of 4.6% of optically reversible low vision and 1.8% of blindness reversible by optical correction were found. UREN was detected in 6.5% of individuals, more frequently observed in women over the age of 50 and in higher RE carriers. Visual impairment related to eye diseases is not reversible with spectacles. Using multivariate analysis, associations between URE and UREN with regard to sex, age and RE was observed. Conclusion RE is an important cause of reversible blindness and low vision in the Brazilian population. PMID:24965318

Trends in Visual Health Inequalities in Childhood Through Associations of Visual Function With Sex and Social Position Across 3 UK Birth Cohorts.

PubMed

Bountziouka, Vasiliki; Cumberland, Phillippa M; Rahi, Jugnoo S

2017-09-01

Despite the existing country-specific strategies tackling social inequalities in visual health in adults, little is known about trends in visual function in childhood and its association with social position. To investigate the distribution of childhood visual function in the United Kingdom and associations with early-life social position between 1961 and 1986, a period of significant social change. Longitudinal cohort study using harmonized data sets from the British 1946, 1958, and 1970 national birth cohorts. In total, 14 283 cohort members with complete data on visual acuity at age 15 or 16 years, measured in 1961, 1974, and 1986, respectively, for each cohort, and social position were assessed. Using habitual distance visual acuity (with correction if prescribed), participants were assigned to a visual function category ranging from bilateral normal to visual impairment/severe visual impairment/blindness (International Statistical Classification of Diseases, Tenth Revision, Clinical Modification). Distribution of visual function over time and associations with social position (risk ratios [RRs] and 95% confidence intervals) were analyzed. Complete data were available for 3152 participants (aged 15 years; 53% boys [n = 1660]) in the 1946 Medical Research Council National Survey of Health and Development, 6683 participants (aged 16 years; 51% boys [n = 3420]) in the 1958 National Child Development Study, and 4448 participants (aged 16 years; 48% boys [n = 2156]) in the 1970 British Birth Cohort Study. The proportion of children with bilateral normal vision decreased by 1.3% (95% CI, -5.1% to 2.7%) in 1974 and 1.7% (95% CI, -5.9% to 2.7%) in 1986. The risk of overall impaired vision increased by 1.20 times (95% CI, 1.01-1.43) and the risk of visual impairment/severe visual impairment/blindness by 1.75 times (95% CI, 1.03-2.98) during this period. Girls were consistently at increased risk of all vision impairment categories. Higher social position at birth and in childhood was associated with reduced risk of visual impairment/severe visual impairment/blindness (RR, 0.58; 95% CI, 0.20-1.68) and unilateral impairment (RR, 0.89; 95% CI, 0.72-1.11), respectively. Our study provides evidence of temporal decline in childhood visual function between 1961 and 1986. Despite the limited power of the analysis owing to the small sample size of those with impaired vision, we found an emergence of a contribution of sociodemographic status to the cohort effect that may be the antecedent of the current picture of childhood blindness. Equally, early-life social position may also have contributed to the current social patterning in visual function in older adults in the United Kingdom. These findings highlight the potential value of targeting children in national ophthalmic public policies tackling inequalities.

Speaking Math--A Voice Input, Speech Output Calculator for Students with Visual Impairments

ERIC Educational Resources Information Center

Bouck, Emily C.; Flanagan, Sara; Joshi, Gauri S.; Sheikh, Waseem; Schleppenbach, Dave

2011-01-01

This project explored a newly developed computer-based voice input, speech output (VISO) calculator. Three high school students with visual impairments educated at a state school for the blind and visually impaired participated in the study. The time they took to complete assessments and the average number of attempts per problem were recorded…

Factors Affecting the Reading Media Used by Visually Impaired Adults

ERIC Educational Resources Information Center

Goudiras, Dimitrios B.; Papadopoulos, Konstantinos S.; Koutsoklenis, Athanasios Ch.; Papageorgiou, Virginia E.; Stergiou, Maria S.

2009-01-01

The aim of this study was to examine reading media (braille, cassettes, screen-reader, screen-magnifier, large print, low vision aids, CCTV) used by visually impaired adults. This article reports the results of a research project involving 100 people with visual impairment. The participants were interviewed and asked to fill in a questionnaire to…

Computers, Automation, and the Employment of Persons Who Are Blind or Visually Impaired.

ERIC Educational Resources Information Center

Mather, J.

1994-01-01

This article discusses the impact of technology on the formation of skills and the career advancement of persons who are blind or visually impaired. It concludes that dependence on technology (computerization and automation) and the mechanistic aspects of jobs may trap blind and visually impaired workers in occupations with narrow career paths…

Primary Support Persons for Individuals Who Are Visually Impaired: Who They Are and the Support They Provide

ERIC Educational Resources Information Center

Silva-Smith, Amy L.; Theune, Thomas W.; Spaid, Penny E.

2007-01-01

As the proportion of older adults in the U.S. population grows, the prevalence of visual impairment related to cataracts, glaucoma, macular degeneration, and diabetic retinopathy will increase as well. Individuals who are visually impaired require various degrees of support and assistance in their daily activities. This assistance is frequently…

The Ability of Visually Impaired Children to Read Expressions and Recognize Faces.

ERIC Educational Resources Information Center

Ellis, H. D.; And Others

1987-01-01

Seventeen visually impaired children, aged 7-11 years, were compared with sighted children on a test of facial recognition and a test of expression identification. The visually impaired children were less able to recognize faces successfully but showed no disadvantage in discerning facial expressions such as happiness, anger, surprise, or fear.…

Sexual Activity of Young Adults Who Are Visually Impaired and the Need for Effective Sex Education

ERIC Educational Resources Information Center

Kelly, Stacy M.; Kapperman, Gaylen

2012-01-01

Introduction: Little research has been reported on all aspects of sexuality as it pertains to individuals with visual impairments. This article analyzes data on the sexual experiences of young adults who are visually impaired and young adults without disabilities. Methods: The authors conducted a secondary analysis of the National Longitudinal…

Orientation and Mobility Skills and Outcome Expectations as Predictors of Employment for Young Adults with Visual Impairments

ERIC Educational Resources Information Center

Cmar, Jennifer L.

2015-01-01

Introduction: Youths with visual impairments attend postsecondary school at high rates, yet these individuals have low rates of employment. In this study, factors associated with post-school employment were investigated in a nationally representative sample of youths with visual impairments. Methods: In a secondary analysis of data from the…

Sex Education Instruction for Students Who Are Visually Impaired: Recommendations to Guide Practitioners

ERIC Educational Resources Information Center

Kapperman, Gaylen; Kelly, Stacy M.

2013-01-01

Individuals with visual impairments (that is, those who are blind or have low vision) do not have the same opportunities to develop their knowledge of sexual health and participate in sex education as their sighted peers (Krupa & Esmail, 2010), although young adults with visual impairments participate in sexual activities at similar rates as their…

Route Descriptions by Visually Impaired and Sighted Children from Memory and from Maps.

ERIC Educational Resources Information Center

Edwards, Rachel; Ungar, Simon; Blades, Mark

1998-01-01

This study evaluated descriptions, either from memory or by using a map (print or tactile), of 12 visually impaired and 12 sighted elementary grade children of two routes around their schools. Descriptions from maps were generally poorer than those from memory. Qualitative differences were also found between descriptions of visually impaired and…

Physical Activity, Body Composition, and Perceived Quality of Life of Adults with Visual Impairments

ERIC Educational Resources Information Center

Holbrook, Elizabeth A.; Caputo, Jennifer L.; Perry, Tara L.; Fuller, Dana K.; Morgan, Don W.

2009-01-01

Relatively little is known about the health and fitness of adults with visual impairments. This article documents the physical activity levels and body-composition profiles of young and middle-aged adults with visual impairments and addresses the concomitant effects of these factors on perceived quality of life. (Contains 2 tables.)

Attainment of Developmental Tasks by Adolescents with Visual Impairments and Sighted Adolescents

ERIC Educational Resources Information Center

Pfeiffer, Jens P.; Pinquart, Martin

2011-01-01

This study compared the achievement of developmental tasks by 158 adolescents with visual impairments to that of 158 sighted adolescents. The groups did not differ in the fulfillment of 9 of 11 tasks. However, those with visual impairments were less successful in peer-group integration and forming intimate relationships. (Contains 4 tables.)

Individuals with Visual Impairments Teaching in Nepal's Mainstream Schools: A Model for Inclusion

ERIC Educational Resources Information Center

Lamichhane, Kamal

2016-01-01

This paper explores the challenges and strengths of teachers with a visual impairments teaching in Nepal's mainstream schools, using qualitative interviews of teachers and principals, as well as a student survey data set. Results showed that teachers with visual impairments tend not to teach subjects such as science and mathematics that require…

Assessing Self-Regulation in Individuals with Visual Impairments: Generality versus Specificity in Self-Regulatory Functioning

ERIC Educational Resources Information Center

Argyropoulos, Vassilios; Sideridis, Georgios D.; Botsas, George; Padeliadu, Susana

2012-01-01

The purpose of the present study was to assess self-regulation of students with visual impairments across two academic subjects, language and math. The participants were 46 Greek students with visual impairments who completed self-regulation measures across the subject matters of language and math. Initially, the factorial validity of the scale…

Validation of a Talking Pedometer for Adolescents with Visual Impairments in Free-Living Conditions

ERIC Educational Resources Information Center

Haegele, Justin A.; Porretta, David L.

2015-01-01

Because school-aged individuals with visual impairments are less physically active than peers without visual impairments, they are at greater risk for developing health-related conditions. One instrument that provides an objective, cost-effective measure of physical activity by counting the total number of steps taken is the pedometer (Albright…

Knowledge of Dental Health and Oral Hygiene Practices of Taiwanese Visually Impaired and Sighted Students

ERIC Educational Resources Information Center

Chang, Chien-Huey Sophie; Shih, Yeng-Hung

2004-01-01

This study investigated the dental health knowledge and oral hygiene practices of 95 students with visual impairments and 286 sighted students in Taiwan. It found that the students with visual impairments were less knowledgeable about dental health and less frequently completed oral hygiene practices than did the sighted students.

Comparison of Reading Performance between Visually Impaired and Normally Sighted Students in Malaysia

ERIC Educational Resources Information Center

Mohammed, Zainora; Omar, Rokiah

2011-01-01

The aim of this study is to compare reading performance between visually impaired and normally sighted school children. Participants (n = 299) were divided into three groups: normal vision (NV, n = 193), visually impaired print reader (PR, n = 52), and Braille reader (BR, n = 54). Reading performance was determined by measuring reading rate and…

School, Family and Other Influences on Assistive Technology Use: Access and Challenges for Students with Visual Impairment in Singapore

ERIC Educational Resources Information Center

Wong, Meng Ee; Cohen, Libby

2011-01-01

Assistive technologies are essential enablers for individuals with visual impairments, but although Singapore is technologically advanced, students with visual impairments are not yet full participants in this technological society. This study investigates the barriers and challenges to the use of assistive technologies by students with visual…

Change in Quality of Life after Rehabilitation: Prognostic Factors for Visually Impaired Adults

ERIC Educational Resources Information Center

Langelaan, Maaike; de Boer, Michiel R.; van Nispen, Ruth M. A.; Wouters, Bill; Moll, Annette C.; van Rens, Ger H. M. B.

2009-01-01

The overall aim of rehabilitation for visually impaired adults is to improve the quality of life and (societal) participation. The objectives of this study were to obtain the short-term and long-term outcome of a comprehensive rehabilitation programme on quality of life for visually impaired adults, and prognostic baseline factors responsible for…

English Language Learners: Experiences of Teachers of Students with Visual Impairments Who Work with This Population

ERIC Educational Resources Information Center

Topor, Irene; Rosenblum, L. Penny

2013-01-01

Introduction: This article presents a study that gathered data from 66 teachers of students with visual impairments about their preparation to work with children who are visually impaired and are learning English, and their knowledge of instructional strategies and methods of instruction. Methods: An online five-part survey was available to…

Spatial Coding of Individuals with Visual Impairments

ERIC Educational Resources Information Center

Papadopoulos, Konstantinos; Koustriava, Eleni; Kartasidou, Lefkothea

2012-01-01

The aim of this study is to examine the ability of children and adolescents with visual impairments to code and represent near space. Moreover, it examines the impact of the strategies they use and individual differences in their performance. A total of 30 individuals with visual impairments up to the age of 18 were given eight different object…

A Review of Research on the Literacy of Students with Visual Impairments and Additional Disabilities

ERIC Educational Resources Information Center

Parker, Amy T.; Pogrund, Rona L.

2009-01-01

Research on the development of literacy in children with visual impairments and additional disabilities is minimal even though these children make up approximately 65% of the population of children with visual impairments. This article reports on emerging themes that were explored after a review of the literature revealed nine literacy studies…

A Literacy Based Intervention to Increase the Pretend Play of Young Children with Visual Impairments

ERIC Educational Resources Information Center

Greeley-Bennett, Catherine

2016-01-01

The purpose of this study was to examine the effect of a literacy-based intervention on the conventional pretend play skills of preschool children who are visually impaired. The intervention involved experience books, real objects, story-reading, and role-play, which are common strategies used to teach children with visual impairments. A…

Executive Function and Behavioral Problems in Students with Visual Impairments at Mainstream and Special Schools

ERIC Educational Resources Information Center

Heyl, Vera; Hintermair, Manfred

2015-01-01

Introduction: In this study, executive function of school-aged children with visual impairments (that is, those who are blind or have low vision) is examined in the context of behavioral problems and communicative competence. Methods: Teachers assessed the executive function of a sample of 226 visually impaired students from mainstream schools and…

Library Automation Design for Visually Impaired People

ERIC Educational Resources Information Center

Yurtay, Nilufer; Bicil, Yucel; Celebi, Sait; Cit, Guluzar; Dural, Deniz

2011-01-01

Speech synthesis is a technology used in many different areas in computer science. This technology can bring a solution to reading activity of visually impaired people due to its text to speech conversion. Based on this problem, in this study, a system is designed needed for a visually impaired person to make use of all the library facilities in…

Visually Impaired Musicians' Insights: Narratives of Childhood, Lifelong Learning and Musical Participation

ERIC Educational Resources Information Center

Baker, David

2014-01-01

With the support of the Royal National Institute of Blind People (RNIB), the life histories of five visually impaired (VI) musicians were collected and analysed between November 2011 and August 2012. This research was conducted as a pilot for a two-year, national investigation of VI musical participation, "Visually-impaired musicians'…

Consumers' Perspectives on Effective Orientation and Mobility Services for Diabetic Adults Who Are Visually Impaired

ERIC Educational Resources Information Center

Griffin-Shirley, Nora; Kelley, Pat; Matlock, Dwayne; Page, Anita

2006-01-01

The authors interviewed and videotaped diabetic adults with visual impairments about their perceptions of orientation and mobility (O&M) services that they had received. The visual impairments of these middle-aged adults ranged from totally blind to low vision. The interview questions focused on demographic information about the interviewees, the…

Implementation of Unified English Braille by Teachers of Students with Visual Impairments in the United States

ERIC Educational Resources Information Center

Hong, Sunggye; Rosenblum, L. Penny; Campbell, Amy Frank

2017-01-01

Introduction: This study analyzed survey responses from 141 teachers of students with visual impairments who shared their experiences about the implementation of Unified English Braille (UEB). Methods: Teachers of students with visual impairments in the United States completed an online survey during spring 2016. Results: Although most respondents…

Technologies Used in the Study of Advanced Mathematics by Students Who Are Visually Impaired in Classrooms: Teachers' Perspectives

ERIC Educational Resources Information Center

DePountis, Vicki M.; Pogrund, Rona L.; Griffin-Shirley, Nora; Lan, William Y.

2015-01-01

Introduction: This research examined the perspectives of teachers of students who are visually impaired regarding the use and effectiveness of high-tech assistive technology purported to assist visually impaired students in advanced mathematics. Methods: The data for this study were collected via a mixed-methods online survey distributed through…

Improving Physics Teaching Materials on Sound for Visually Impaired Students in High School

ERIC Educational Resources Information Center

Toenders, Frank G. C.; de Putter-Smits, Lesley G. A.; Sanders, Wendy T. M.; den Brok, Perry

2017-01-01

When visually impaired students attend regular high school, additional materials are necessary to help them understand physics concepts. The time for teachers to develop teaching materials for such students is scarce. Visually impaired students in regular high school physics classes often use a braille version of the physics textbook. Previously,…

Adaptation of Psychological Assessment Tools for Administration by Blind and Visually Impaired Psychologists and Trainees.

ERIC Educational Resources Information Center

Keller, Richard M.

This paper focuses on challenges to psychologists and psychology graduate students who are blind or visually impaired in the administration and scoring of various psychological tests. Organized by specific tests, the paper highlights those aspects of testing which pose particular difficulty to testers with visual impairments and also describes…

Procedures and Tools Used by Teachers When Completing Functional Vision Assessments with Children with Visual Impairments

ERIC Educational Resources Information Center

Kaiser, Justin T.; Herzberg, Tina S.

2017-01-01

Introduction: This study analyzed survey responses from 314 teachers of students with visual impairments regarding the tools and procedures used in completing functional vision assessments (FVAs). Methods: Teachers of students with visual impairments in the United States and Canada completed an online survey during spring 2016. Results: The…

Bullying in German Adolescents: Attending Special School for Students with Visual Impairment

ERIC Educational Resources Information Center

Pinquart, Martin; Pfeiffer, Jens P.

2011-01-01

The present study analysed bullying in German adolescents with and without visual impairment. Ninety-eight adolescents with vision loss from schools for students with visual impairment, of whom 31 were blind and 67 had low vision, were compared with 98 sighted peers using a matched-pair design. Students with low vision reported higher levels of…

The Effectiveness of a Multidisciplinary Group Rehabilitation Program on the Psychosocial Functioning of Elderly People Who Are Visually Impaired

ERIC Educational Resources Information Center

Alma, Manna A.; Groothoff, Johan W.; Melis-Dankers, Bart J. M.; Suurmeijer, Theo P. B. M.; van der Mei, Sijrike F.

2013-01-01

Introduction: The pilot study reported here determined the effectiveness of a multidisciplinary group rehabilitation program, Visually Impaired Elderly Persons Participating (VIPP), on psychosocial functioning. Methods: The single-group pretest-posttest pilot study included 29 persons with visual impairments (aged 55 and older) who were referred…

Community Mentors: The Perspectives of Working Adults with Visual Impairments

ERIC Educational Resources Information Center

Hong, Sunggye; Erin, Jane N.

2017-01-01

Although most teachers of students with visual impairments spend time in internships prior to teaching, they often begin teaching without firsthand contact with capable adults who have visual impairments (that is, those who are blind or have low vision). As a result, they may be unfamiliar with the daily planning and adaptation undertaken by those…

Normal aging delays and compromises early multifocal visual attention during object tracking.

PubMed

Störmer, Viola S; Li, Shu-Chen; Heekeren, Hauke R; Lindenberger, Ulman

2013-02-01

Declines in selective attention are one of the sources contributing to age-related impairments in a broad range of cognitive functions. Most previous research on mechanisms underlying older adults' selection deficits has studied the deployment of visual attention to static objects and features. Here we investigate neural correlates of age-related differences in spatial attention to multiple objects as they move. We used a multiple object tracking task, in which younger and older adults were asked to keep track of moving target objects that moved randomly in the visual field among irrelevant distractor objects. By recording the brain's electrophysiological responses during the tracking period, we were able to delineate neural processing for targets and distractors at early stages of visual processing (~100-300 msec). Older adults showed less selective attentional modulation in the early phase of the visual P1 component (100-125 msec) than younger adults, indicating that early selection is compromised in old age. However, with a 25-msec delay relative to younger adults, older adults showed distinct processing of targets (125-150 msec), that is, a delayed yet intact attentional modulation. The magnitude of this delayed attentional modulation was related to tracking performance in older adults. The amplitude of the N1 component (175-210 msec) was smaller in older adults than in younger adults, and the target amplification effect of this component was also smaller in older relative to younger adults. Overall, these results indicate that normal aging affects the efficiency and timing of early visual processing during multiple object tracking.

Aberrant activity in retinal degeneration impairs central visual processing and relies on Cx36-containing gap junctions.

PubMed

Ivanova, Elena; Yee, Christopher W; Baldoni, Robert; Sagdullaev, Botir T

2016-09-01

In retinal degenerative disease (RD), the diminished light signal from dying photoreceptors has been considered the sole cause of visual impairment. Recent studies show a 10-fold increase in spontaneous activity in the RD network, challenging this paradigm. This aberrant activity forms a new barrier for the light signal, and not only exacerbates the loss of vision, but also may stand in the way of visual restoration. This activity originates in AII amacrine cells and relies on excessive activation of gap junctions. However, it remains unclear whether aberrant activity affects central visual processing and what mechanisms lead to this excessive activation of gap junctions. By combining genetic manipulation with electrophysiological recordings of light-induced activity in both living mice and isolated wholemount retina, we demonstrate that aberrant activity extends along retinotectal projections to alter activity in higher brain centers. Next, to selectively eliminate Cx36-containing gap junctions, which are the primary type expressed by AII amacrine cells, we crossed rd10 mice, a slow-degenerating model of RD, with Cx36 knockout mice. We found that retinal aberrant activity was reduced in the rd10/Cx36KO mice compared to rd10 controls, a direct evidence for involvement of Cx36-containing gap junctions in generating aberrant activity in RD. These data provide an essential support for future experiments to determine if selectively targeting these gap junctions could be a valid strategy for reducing aberrant activity and restoring light responses in RD. Copyright © 2015 Elsevier Ltd. All rights reserved.

Refractive error and visual impairment in private school children in Ghana.

PubMed

Kumah, Ben D; Ebri, Anne; Abdul-Kabir, Mohammed; Ahmed, Abdul-Sadik; Koomson, Nana Ya; Aikins, Samual; Aikins, Amos; Amedo, Angela; Lartey, Seth; Naidoo, Kovin

2013-12-01

To assess the prevalence of refractive error and visual impairment in private school children in Ghana. A random selection of geographically defined classes in clusters was used to identify a sample of school children aged 12 to 15 years in the Ashanti Region. Children in 60 clusters were enumerated and examined in classrooms. The examination included visual acuity, retinoscopy, autorefraction under cycloplegia, and examination of anterior segment, media, and fundus. For quality assurance, a random sample of children with reduced and normal vision were selected and re-examined independently. A total of 2454 children attending 53 private schools were enumerated, and of these, 2435 (99.2%) were examined. Prevalence of uncorrected, presenting, and best visual acuity of 20/40 or worse in the better eye was 3.7, 3.5, and 0.4%, respectively. Refractive error was the cause of reduced vision in 71.7% of 152 eyes, amblyopia in 9.9%, retinal disorders in 5.9%, and corneal opacity in 4.6%. Exterior and anterior segment abnormalities occurred in 43 (1.8%) children. Myopia (at least -0.50 D) in one or both eyes was present in 3.2% of children when measured with retinoscopy and in 3.4% measured with autorefraction. Myopia was not significantly associated with gender (P = 0.82). Hyperopia (+2.00 D or more) in at least one eye was present in 0.3% of children with retinoscopy and autorefraction. The prevalence of reduced vision in Ghanaian private school children due to uncorrected refractive error was low. However, the prevalence of amblyopia, retinal disorders, and corneal opacities indicate the need for early interventions.

Auditory, Visual, and Auditory-Visual Perception of Vowels by Hearing-Impaired Children.

ERIC Educational Resources Information Center

Hack, Zarita Caplan; Erber, Norman P.

1982-01-01

Vowels were presented through auditory, visual, and auditory-visual modalities to 18 hearing impaired children (12 to 15 years old) having good, intermediate, and poor auditory word recognition skills. All the groups had difficulty with acoustic information and visual information alone. The first two groups had only moderate difficulty identifying…

Adult Visual Experience Promotes Recovery of Primary Visual Cortex from Long-Term Monocular Deprivation

ERIC Educational Resources Information Center

Fischer, Quentin S.; Aleem, Salman; Zhou, Hongyi; Pham, Tony A.

2007-01-01

Prolonged visual deprivation from early childhood to maturity is believed to cause permanent visual impairment. However, there have been case reports of substantial improvement of binocular vision in human adults following lifelong visual impairment or deprivation. These observations, together with recent findings of adult ocular dominance…

Helping Children with Visual and Motor Impairments Make the Most of Their Visual Abilities.

ERIC Educational Resources Information Center

Amerson, Marie J.

1999-01-01

Lists strategies for promoting functional vision use in children with visual and motor impairments, including providing postural stability, presenting visual attention tasks when energy level is the highest, using a slanted work surface, placing target items in varied locations within reach, and determining the most effective visual adaptations.…

Selective impairment of facial recognition due to a haematoma restricted to the right fusiform and lateral occipital region

PubMed Central

Wada, Y; Yamamoto, T

2001-01-01

A 67 year old right handed Japanese man developed prosopagnosia caused by a haemorrhage. His only deficit was the inability to perceive and discriminate unfamiliar faces, and to recognise familiar faces. He did not show deficits in visual or visuospatial perception of non-facial stimuli, alexia, visual agnosia, or topographical disorientation. Brain MRI showed a haematoma limited to the right fusiform and the lateral occipital region. Single photon emission computed tomography confirmed that there was no decreased blood flow in the opposite left cerebral hemisphere. The present case indicates that a well placed small right fusiform gyrus and the adjacent area can cause isolated impairment of facial recognition. As far as we know, there has been no published case that has demonstrated this exact lesion site, which was indicated by recent functional MRI studies as the most critical area in facial recognition.

 PMID:11459906