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1.
Occup Ther Health Care ; : 1-23, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39110868

RESUMEN

This study aims to examine the psychometric properties of questionnaires related to cerebral visual impairment (CVI) in school-age children with cerebral palsy (CP). Additionally, it proposes an application process based on motor functionality for occupational therapists. A total of 288 children with CP were recruited for the study and administered the CVI Motor Questionnaire (CVI-MQ). The children's daily visual performance was assessed using the CVI Inventory and the Functional Vision Questionnaire (FVQ) considering the children's ambulatory status. The FVQ and the two factors extracted from the CVI Inventory significantly predicted visual functioning. Specific questionnaires related to CVI, applied with gross motor function in mind, can be valuable tools for occupational therapists to assess daily visual performance.

2.
BMC Public Health ; 24(1): 1974, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39044199

RESUMEN

OBJECTIVE: Self-rated health (SRH) has been documented as an important predictor of quality of life among the elderly and its risk factors are vision-specific among elderly males. The aim of this study was to clarify vision-specific risk factors to SRH among elderly females without dementia in Chinese urban areas. METHODS: From March to November 2012, 2147 elderly women in Liaoning Province of China were selected using a stratified sampling method. After cognitive screening, 1956 participants without dementia were finally enrolled. A questionnaire including SRH, visual ability and factors including demographic characteristics, physical conditions, lifestyle factors, social psychological status and social activities were analyzed. Multivariate logistic regression was used to clarify the association of SRH with risk factors, while stepwise multivariate logistic regression was used to examine the vision-specific associations with SRH. RESULTS: The mean age was 73.6 ± 5.82 (mean ± SD). The percentages of good SRH in good and impaired visual ability groups were 36.2% and 24.4%, respectively. Most characteristics between elderly females with different visual abilities were significantly different. Visual ability had interactions with physical conditions, lifestyle factors and social activities to affect SRH. Among elderly females with good visual ability, depressive symptoms, rather than chronic disease had the strongest association with good SRH followed by marital status, regular diet, going out alone to distant places, taking a walk, smoking and alcohol consumption. In the impaired visual ability group, going out alone to distant places had the strongest association with good SRH followed by chronic disease, filial piety, taking a walk, participating in entertainment, ethnicity, quality of sleep, worrying about falling and alcohol consumption. CONCLUSIONS: Good SRH status was at a low level especially among elderly females with impaired visual ability and the risk factors differed between elderly females with different visual abilities. Social psychological status was crucial for SRH among elderly females with good visual ability whereas physical conditions were prominent for impaired visual ability group.


Asunto(s)
Estado de Salud , Población Urbana , Humanos , Femenino , Anciano , China/epidemiología , Factores de Riesgo , Población Urbana/estadística & datos numéricos , Trastornos de la Visión/epidemiología , Trastornos de la Visión/psicología , Anciano de 80 o más Años , Encuestas y Cuestionarios , Pueblos del Este de Asia
3.
Front Physiol ; 15: 1429554, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39081778

RESUMEN

Sport visual ability plays an important role in the performance of elite athletes in competition. However, its relationship with boxers' performance has not been fully understood. This study investigated the relationship between sports visual abilities and in-competition punching performance in 26 highly trained male amateur boxers. Ten visual abilities of the boxers were tested using the Senaptec Sensory Station (Senaptec, Beaverton, OR, United States), including Visual Clarity (VC), Contrast Sensitivity (CS), Depth Perception (DP), Near Far Quickness (NFQ), Target Capture (TC), Perception Span (PS), Multiple Object Tracking (MOT), Eye-Hand Coordination (EHC), Go/No Go (GNG), and Reaction Time (RT). Performance analyses were conducted on national boxing championships conducted by the boxers to analyze their punching accuracy. Correlation and regression analyses showed that punch performance %Hit was very strong correlated with DP, EHC, GNG, and RT, and showed a strong correlation with VC, CS, and PS. %Hit was moderate correlated with MOT, while there was no correlation with NFQ and TC. In addition, RT, EHC, and DP are important visual ability variables for boxers. The results of this study indicate that there is an overall relationship between sports visual ability and boxing performance, but there is also a specific relationship between variables in visual ability and boxing performance, especially faster reaction times, better processing of visual information, and decision-making abilities, and the ability to accurately recognize the distance and position of an opponent and their punches are essential for enhancing boxing performance. Further studies are needed to investigate the relationship between sport visual ability and more comprehensive performance in boxers, and the possibility of enhancing performance through specific visual training.

4.
Indian J Ophthalmol ; 71(5): 2162-2167, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37202942

RESUMEN

Purpose: To analyze clinical manifestations, visual ability, and quality of life in pediatric uveitis and to explore factors affecting visual ability and quality of life. Methods: This cross-sectional study included 40 patients with pediatric uveitis in the database of Ophthalmology of Peking University First Hospital. All patients completed the Cardiff visual ability questionnaire for children (CVAQC) and pediatric quality of life inventory measurement models (PedsQL4.0). Results: A total of 40 cases (68 eyes) with pediatric uveitis were included in this study. Better visual acuity in the better eye was predictive of lower CVAQC, education, and distance vision scores. Better visual acuity in the worse eye was predictive of a lower CVAQC score and distance vision. Better CVAQC scores were predictive of lower PedsQL4.0, physical health, psychosocial health, and school functioning scores. Conclusion: Patients with pediatric uveitis tend to be seriously affected by ocular complications. The visual ability of patients with pediatric uveitis decreases significantly. Better visual acuity in the better eye is associated with better total visual ability, education, and distance vision. Better visual acuity in the worse eye is associated with better total visual ability and distance vision. Health-related quality of life is related to vision ability in pediatric uveitis.


Asunto(s)
Calidad de Vida , Uveítis , Humanos , Niño , Estudios Transversales , Visión Ocular , Uveítis/diagnóstico , Agudeza Visual , Encuestas y Cuestionarios
5.
Insects ; 14(4)2023 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-37103185

RESUMEN

Empoasca onukii is a common tea plant pest with a preference for the color yellow. Past work has shown that host leaf color is a key cue for habitat location for E. onukii. Before studying the effect of foliage shape, size, or texture on habitat localization, it is necessary to determine the visual acuity and effective viewing distance of E. onukii. In this study, a combination of 3D microscopy and X-ray microtomography showed that visual acuity did not significantly differ between females and males, but there were significant differences in the visual acuity and optical sensitivity among five regions of E. onukii's compound eyes. The dorsal ommatidia had the highest visual acuity at 0.28 cycles per degree (cpd) but the lowest optical sensitivity (0.02 µm2sr), which indicated a trade-off between visual resolution and optical sensitivity for E. onukii. The visual acuity determined from the behavioral experiment was 0.14 cpd; E. onukii exhibited low-resolution vision and could only distinguish the units in a yellow/red pattern within 30 cm. Therefore, visual acuity contributes to the limited ability of E. onukii to distinguish the visual details of a distant target, which might be perceived as a lump of blurred color of intermediate brightness.

6.
Ophthalmol Ther ; 12(1): 307-323, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36369618

RESUMEN

INTRODUCTION: The aim of this study was twofold: (1) to investigate the clinical impact of vision rehabilitation in patients with vision impairment and (2) to investigate the cost-effectiveness of a basic vision rehabilitation service in Portugal. METHODS: The trial recruited patients diagnosed with age-related macular degeneration or diabetic retinopathy (DR) and visual acuity in the range 0.4-1.0logMAR in the better-seeing eye. Participants were randomised to one of the study arms consisting of immediate intervention and delayed intervention. The intervention included: new refractive correction, optical reading aids, in-office training and advice about modifications at home. Visual ability, health-related quality of life and costs were measured. Economic analysis was performed to evaluate whether the intervention was cost-effective. The trial compared the outcomes 12 weeks after the start in both arms. RESULTS: Of the 46 participants, 34 (74%) were diagnosed with DR, 25 (54%) were female, and mean age was 70.08 years (SD = 8.74). In the immediate intervention arm visual ability increased a mean of 0.523 logits (SE = 0.11) (p < 0.001). Changes in the delayed intervention arm were not statistically significant (p = 0.95). Acuity in the better-seeing eye, near acuity and critical print size also improved during the study. The mean cost of the intervention was €118.79 (SD = 24.37). The incremental cost-effectiveness ratio using the EQ-5D-5L was 30,421€/QALY and 1186€/QALY when using near acuity. CONCLUSION: The current study gives evidence of positive clinical impact of a basic vision rehabilitation intervention and shows that a basic vision rehabilitation service is cost-effective. These findings are important to clinical and rehabilitation practices and for planning vision rehabilitation services. TRIAL REGISTRATION: Retrospectively registered, 21/01/2019. ISRCTN10894889, https://www.isrctn.com/ISRCTN10894889.


There is limited research addressing the actual impact of vision rehabilitation. The current trial compares the effect of a basic vision rehabilitation intervention with usual care on patients' functioning. The intervention was clinically impactful and cost-effective.

7.
Genes Brain Behav ; 21(4): e12794, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35238473

RESUMEN

The 5xFAD mouse model of Alzheimer's disease (AD) rapidly develops AD-related neuro-behavioral pathology. Learning and memory impairments in 5xFAD mice, however, are not always replicated and the size of impairments varies considerably across studies. To examine possible sources of this variability, we analyzed the effects of age, sex, albinism due to background genes (Tyrc , Oca2p ) and motor impairment on learning and memory performance of wild type and 5xFAD mice on the Morris water maze, from 3 to 15 months of age. The 5xFAD mice showed impaired learning at 6-9 months of age, but memory impairments were not detected with the test procedure used in this study. Performance of 5xFAD mice was profoundly impaired at 12-15 months of age, but was accompanied by slower swim speeds than wild-type mice and a frequent failure to locate the escape platform. Overall female mice performed worse than males, and reversal learning impairments in 5xFAD mice were more pronounced in females than males. Albino mice performed worse than pigmented mice, confirming that albinism can impair performance of 5xFAD mice independently of AD-related transgenes. Overall, these results show that 5xFAD mice have impaired learning performance at 6-9 months of age, but learning and memory performance at 12-15 months is confounded with motor impairments. Furthermore, sex and albinism should be controlled to provide an accurate assessment of AD-related transgenes on learning and memory. These results will help reduce variability across pre-clinical experiments with 5xFAD mice, and thus enhance the reliability of studies developing new therapeutics for AD.


Asunto(s)
Albinismo , Enfermedad de Alzheimer , Trastornos Motores , Albinismo/complicaciones , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Transgénicos , Trastornos Motores/complicaciones , Reproducibilidad de los Resultados , Aprendizaje Espacial
8.
Risk Manag Healthc Policy ; 14: 3729-3738, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34526829

RESUMEN

PURPOSE: Successful aging is an effective approach to coping with population aging; however, the definition and associated factors vary due to culture and demographic distribution differences. This study was designed to assess successful aging of the older adults in China and explore the associated factors. METHODS: A community-based cross-sectional study was performed in Liaoning, China. After double-cognitive function screening, 3558 older adults (1656 males and 1902 females) ≥65 years of age served as our subjects. Successful aging was assessed based on the following: physical disability; cognitive function; activities of daily living; and self-rated psychological/mood status. RESULTS: The rate of successful aging was 31.7% in males and 29.4% in females. After adjustment for age, multivariate logistic regression showed that successful aging was significantly associated with, in odds ratio sequence, visual ability, self-rated chronic disease, marital status, and filial piety in males, and with visual ability, self-rated chronic disease, watching television, and ethnicity in females. CONCLUSION: The level of successful aging in China is lower than in other countries. Demographic characteristics, health status, individual behavior, and social-psychological factors are all associated with successful aging. Overall, visual ability had the most crucial role in successful aging for the older adults, whether males or females.

9.
Front Psychol ; 11: 191, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32210859

RESUMEN

Mathematical problem-solving and spatial visualization are areas in which performance has been shown to vary with sex. This article describes the impact of gender on spatial relations measured in 331 secondary school students (202 males, 129 females), 145 (105 males, 40 females) of whom had been selected to participate in a mathematical talent stimulation project after passing a complex problem-solving test. In the two tests administered, the Differential Aptitude Tests-Space Relations (DAT-SR) and the Primary Mental Abilities-Space Relations (PMA-SR), performance was assessed on the grounds of both absolute scores and the ratio to the number of items answered. The students participating in the talent program earned higher scores on both tests, although no interaction was identified between mathematical abilities and gender in connection with the differences in spatial habilities observed. In PMA-SR, boys answered more items and scored higher, whereas in DAT-SR girls tended to omit more items. None of the indicators studied exhibited differences between the sexes in both tests and in some cases the differences in the absolute values of the indicators were absent when expressed as ratios.

10.
J Neuroeng Rehabil ; 17(1): 12, 2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-32005265

RESUMEN

BACKGROUND: There is a clinical need to identify diagnostic parameters that objectively quantify and monitor the effective visual ability of patients with homonymous visual field defects (HVFDs). Visual processing speed (VPS) is an objective measure of visual ability. It is the reaction time (RT) needed to correctly search and/or reach for a visual stimulus. VPS depends on six main brain processing systems: auditory-cognitive, attentional, working memory, visuocognitive, visuomotor, and executive. We designed a new assessment methodology capable of activating these six systems and measuring RTs to determine the VPS of patients with HVFDs. METHODS: New software was designed for assessing subject visual stimulus search and reach times (S-RT and R-RT respectively), measured in seconds. Thirty-two different everyday visual stimuli were divided in four complexity groups that were presented along 8 radial visual field positions at three different eccentricities (10o, 20o, and 30o). Thus, for each HVFD and control subject, 96 S- and R-RT measures related to VPS were registered. Three additional variables were measured to gather objective data on the validity of the test: eye-hand coordination mistakes (ehcM), eye-hand coordination accuracy (ehcA), and degrees of head movement (dHM, measured by a head-tracker system). HVFD patients and healthy controls (30 each) matched by age and gender were included. Each subject was assessed in a single visit. VPS measurements for HFVD patients and control subjects were compared for the complete test, for each stimulus complexity group, and for each eccentricity. RESULTS: VPS was significantly slower (p < 0.0001) in the HVFD group for the complete test, each stimulus complexity group, and each eccentricity. For the complete test, the VPS of the HVFD patients was 73.0% slower than controls. They also had 335.6% more ehcMs, 41.3% worse ehcA, and 189.0% more dHMs than the controls. CONCLUSIONS: Measurement of VPS by this new assessment methodology could be an effective tool for objectively quantifying the visual ability of HVFD patients. Future research should evaluate the effectiveness of this novel method for measuring the impact that any specific neurovisual rehabilitation program has for these patients.


Asunto(s)
Hemianopsia/diagnóstico , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Programas Informáticos , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Hemianopsia/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Percepción Visual/fisiología
11.
Ophthalmic Physiol Opt ; 40(3): 350-364, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31989690

RESUMEN

PURPOSE: To investigate the cost-effectiveness of a basic vision rehabilitation service (basic-VRS) in Portugal. We designed a parallel group, randomised controlled trial whose aim is to compare the effects and costs of 'usual low vision care' with a 'basic-VRS intervention' on self-reported visual ability and other psychosocial and health-related quality-of-life outcomes. METHODS: The trial will recruit participants that meet the following inclusion criteria: (1) visual acuity between 0.4-1.0 logMAR in the better-seeing eye, (2) cause of vision loss is diabetic retinopathy or age-related macular degeneration, (3) 18 years or older and iv) live in the community (not in nursing homes or other type of institution). Participants will be randomised to one of the study arms consisting of immediate intervention and delayed intervention. The delayed intervention group will receive 'usual care' or no intervention in the first 12 weeks. Visual acuity, contrast sensitivity and retinal structure will be assessed during the study. RESULTS: The primary outcome measure is visual ability, which will be evaluated with the Massof Activity Inventory, we expect that the intervention will raise the overall person measure or visual ability. Reading, health-related quality-of-life, anxiety and depression and social support will be also assessed. The analysis will be undertaken on an intention-to-treat basis. A cost-effectiveness analysis will be performed to provide information about the cost per unit of utility. To evaluate the cost-effectiveness of the intervention we will adopt the perspective of the healthcare system. CONCLUSION: This study will provide additional evidence about the effects of basic-VRS on self-reported visual ability. Findings from this study should also contribute to better planning of low vision provision and, consequently, may contribute to reduce barriers to basic-VRS.


Asunto(s)
Calidad de Vida , Lectura , Baja Visión/economía , Agudeza Visual , Análisis Costo-Beneficio , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Baja Visión/fisiopatología , Baja Visión/rehabilitación
12.
Behav Brain Res ; 333: 142-149, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28690184

RESUMEN

Normal aging is often accompanied by reductions in cognitive abilities as well as impairments in visual acuity in men and mice. In preclinical models of human cognition this concomitance can make it difficult to assess the relative contributions of declined vision and cognitive ability on behavioral measures of cognition. To assess the influence of age on cognition and the impact of visual decline on the performance of touchscreen-based behavioral paradigms in mice, aged (11, 12, 16, 17, 19 and 21 months old) male C57BL/6J mice were compared to young (3 or 4 months old) male C57BL/6J mice using three tests of cognition as well as an assessment of visual acuity. Performance of a Visual Discrimination, Spatial Reversal, and an Automated Search Task were all affected by age. However, there was no relationship between reduced visual acuity and the observed performance impairments. Moreover, the visual acuity of animals with profound cognitive impairments overlapped with those showing normal cognitive ability. Despite the potential confound of impaired visual ability, it appears that the touchscreen approach might be particularly effective in studying age-related cognitive decline. This approach will increase the utility of aged mice as a model of decreased cognitive flexibility and may be particularly important for the study of age-related disorders such as Alzheimer's disease.


Asunto(s)
Envejecimiento/fisiología , Cognición/fisiología , Discriminación en Psicología/fisiología , Conducta Exploratoria/fisiología , Desempeño Psicomotor/fisiología , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Desempeño Psicomotor/efectos de los fármacos , Aprendizaje Inverso/fisiología , Trastornos de la Visión , Agudeza Visual/fisiología
13.
Transl Vis Sci Technol ; 6(3): 11, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28573075

RESUMEN

PURPOSE: To develop and psychometrically evaluate a visual functioning questionnaire (VFQ) in an ultra-low vision (ULV) population. METHODS: Questionnaire items, based on visual activities self-reported by a ULV population, were categorized by functional visual domain (e.g., mobility) and visual aspect (e.g., contrast) to ensure a representative distribution. In Round 1, an initial set of 149 items was generated and administered to 90 participants with ULV (visual acuity [VA] ≤ 20/500; mean [SD] age 61 [15] years), including six patients with a retinal implant. Psychometric properties were evaluated through Rasch analysis and a revised set (150 items) was administered to 80 participants in Round 2. RESULTS: In Round 1, the person measure distribution (range, 8.6 logits) was centered at -1.50 logits relative to the item measures. In Round 2, the person measure distribution (range, 9.5 logits) was centered at -0.86 relative to the item mean. The reliability index in both rounds was 0.97 for Items and 0.99 for Persons. Infit analysis showed four underfit items in Round 1, five underfit items in Round 2 with a z-score greater than 4 cutoff. Principal component analysis on the residuals found 69.9% explained variance; the largest component in the unexplained variance was less than 3%. CONCLUSIONS: The ULV-VFQ, developed with content generated from a ULV population, showed excellent psychometric properties as well as superior measurement validity in a ULV population. TRANSLATIONAL RELEVANCE: The ULV-VFQ, part of the Prosthetic Low Vision Rehabilitation (PLoVR) development program, is a new VFQ developed for assessment of functional vision in ULV populations.

14.
Acta Ophthalmol ; 95(8): e783-e791, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28371261

RESUMEN

PURPOSE: Generic instruments to assess health utilities can be used to express the burden of health problems in widely used indexes. That is in contrast with what can be obtained with condition-specific instruments, outcomes are very specific and difficult to compare across conditions. The purpose of this study was to assess health and visual outcomes and its determinants in patients with visual impairment (VI) using the EQ-5D-3L and the Activity Inventory (AI). METHODS: Participants were recruited in different hospitals during the PCVIP-study. A total of 134 patients with acuity 0.30 logMAR or less in the better eye were interviewed. The AI includes 46 goals split between three objectives: social functioning, recreation and daily living, and was used to measure visual ability. The EQ-5D consists of five questions covering one domain each and was used to provide a measure of health states. Responses to each domain were combined to produce a single individual index. RESULTS: The AI and the EQ-5D-3L showed enough discriminatory power between VI levels (p < 0.001), and their results were strongly correlated r(134) = 0.825, (p < 0.001). Explanatory factors for visual ability were level of VI in better eye, age and gender, R2  = 0.43, (p < 0.001). Explanatory factors for the EQ-5D-3L were level of VI in the better eye, comorbidities and gender, R2  = 0.36, (p < 0.001). CONCLUSION: Our results showed that the EQ-5D-3L is useful when characterizing the burden of VI and to compute, when necessary, quality-adjusted-life-years (QALY) changes due to VI. However, it is important to consider that the EQ-5D-3L uses a coarse response scale, assesses a limited spectrum of domains and is influenced by comorbidities. This might limit its responsiveness to small changes in visual ability.


Asunto(s)
Estado de Salud , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Baja Visión/fisiopatología , Agudeza Visual/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Baja Visión/psicología
15.
Bull Soc Pathol Exot ; 110(5): 310-314, 2017 Dec.
Artículo en Francés | MEDLINE | ID: mdl-29299883

RESUMEN

The aim of this work was to evaluate the public transport drivers' visual driving ability in Bamako. We carried out a descriptive cross-sectional study from May 15 to July 15, 2013. The probabilistic method was used. 385 drivers were examined at the University Hospital of the Institute of Tropical Ophthalmology of Africa (IOTA). The average age was 44.69 years. 296 drivers (76.9%) were able to drive public transport vehicles. Among drivers over 50 years old, 42.5% are unfit for driving. Color vision was normal in 98.7 % of cases. Ametropia, cataract and neuropathies accounted for 48.5%, 25.1% and 17.5% respectively, of the causes of impaired vision of drivers. According to European legislation, official transport drivers must be subject to periodic eye examinations. In the absence of such measures in Malian legislation, 42.5% of drivers over 50 years old are unfit to drive. The improvement of road safety requires the renewal and application of the texts for the delivery and renewal of the driver's license of public transport drivers.


Asunto(s)
Conducción de Automóvil/estadística & datos numéricos , Sector Público , Transportes , Trastornos de la Visión/epidemiología , Accidentes de Tránsito/mortalidad , Accidentes de Tránsito/estadística & datos numéricos , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Malí/epidemiología , Persona de Mediana Edad , Trastornos de la Visión/diagnóstico , Selección Visual , Visión Ocular/fisiología , Recursos Humanos , Adulto Joven
16.
Vision Res ; 141: 293-302, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-27369097

RESUMEN

This study considers how inter-individual differences in visual ability are structured. Visual ability could be a single entity (along the lines of general intelligence, or 'g'), or could be structured according to major anatomical or physiological pathways (dorsal v. ventral streams; magno- v. parvo-cellular systems); or may be a finer-grained mosaic of abilities. To test this, we employed seven visual psychophysical tests (generating 16 measures) on a large (100+) sample of neurotypical participants. A Varimax-rotated PCA (Principal Component Analysis) revealed a two-factor solution that broadly corresponds to a high and low spatial frequency division (consistent with a magno/parvo distinction). Over and above this, two measures (temporal order judgments; gain in contrast sensitivity) correlated with most others, and loaded on both factors, suggesting that they tap broad visual processing demands. These analyses open up further possibilities for exploring the genetic and neuroscientific foundations of differences in visual ability. The tests were also run on a group of individuals with different types of visually-based synaesthesia, given that previous research have suggested they possess a distinct profile of visual abilities. Synaesthesia was linked to enhanced processing of colour and shape/curvature information (amongst others), that may relate to differences in V4 in this group. In conclusion, individual differences in vision are both striking and meaningful, despite our difficulty to imagine seeing the world any differently.


Asunto(s)
Trastornos de la Percepción/fisiopatología , Percepción Visual/fisiología , Adolescente , Adulto , Percepción de Color/fisiología , Sensibilidad de Contraste/fisiología , Femenino , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Percepción de Movimiento/fisiología , Reconocimiento Visual de Modelos/fisiología , Estimulación Luminosa , Sinestesia , Adulto Joven
17.
Neuropsychologia ; 93(Pt A): 301-311, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27851900

RESUMEN

From birth, the human visual system shows a remarkable sensitivity for perceiving biological motion. This visual ability relies on a distributed network of brain regions and can be preserved even after damage of high-level ventral visual areas. However, it remains unknown whether this critical biological skill can withstand the loss of vision following bilateral striate damage. To address this question, we tested the categorization of human and animal biological motion in BC, a rare case of cortical blindness after anoxia-induced bilateral striate damage. The severity of his impairment, encompassing various aspects of vision (i.e., color, shape, face, and object recognition) and causing blind-like behavior, contrasts with a residual ability to process motion. We presented BC with static or dynamic point-light displays (PLDs) of human or animal walkers. These stimuli were presented either individually, or in pairs in two alternative forced choice (2AFC) tasks. When confronted with individual PLDs, the patient was unable to categorize the stimuli, irrespective of whether they were static or dynamic. In the 2AFC task, BC exhibited appropriate eye movements towards diagnostic information, but performed at chance level with static PLDs, in stark contrast to his ability to efficiently categorize dynamic biological agents. This striking ability to categorize biological motion provided top-down information is important for at least two reasons. Firstly, it emphasizes the importance of assessing patients' (visual) abilities across a range of task constraints, which can reveal potential residual abilities that may in turn represent a key feature for patient rehabilitation. Finally, our findings reinforce the view that the neural network processing biological motion can efficiently operate despite severely impaired low-level vision, positing our natural predisposition for processing dynamicity in biological agents as a robust feature of human vision.


Asunto(s)
Ceguera Cortical/fisiopatología , Cuerpo Estriado/fisiopatología , Percepción de Movimiento/fisiología , Adulto , Ceguera Cortical/diagnóstico por imagen , Ceguera Cortical/etiología , Conducta de Elección/fisiología , Cuerpo Estriado/diagnóstico por imagen , Discriminación en Psicología/fisiología , Medidas del Movimiento Ocular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/psicología , Pruebas Neuropsicológicas , Reconocimiento en Psicología/fisiología , Grabación en Video , Adulto Joven
18.
Clin Ophthalmol ; 10: 1265-73, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27468223

RESUMEN

PURPOSE: The aim of this study was to assess the performance-based visual ability among independently living elderly subjects and to investigate whether there was any association between visual ability and falls. SUBJECTS AND METHODS: A total of 298 randomly selected subjects aged 70-85 years were invited for an examination including monocular and binocular visual acuity (VA), contrast sensitivity (CS), stereoscopic vision, and monocular visual fields (VFs), which were integrated to estimate the binocular VFs. Type of lenses used in their habitual correction was noted. RESULTS: Out of the 212 subjects who were examined, 38% reported at least one fall and 48% of these reported at least two falls during the last 2 years. Most subjects had normal results; 90% had normal binocular VA, 85% had normal binocular CS, and ~80% had positive stereopsis. Twenty-nine subjects had VF defects in the lower quadrants of the binocular VF, and 14 of these reported at least one fall. A significant association was seen between one fall or more and VA better eye, the odds ratio (OR) was 2.26, P=0.013, and between recurrent falls and lack of stereoscopic vision, the OR was 3.23, P=0.002; no other functional test showed any significant association with recurrent falls. The ORs were 1.58 for worse binocular VA, 0.60 for worse binocular CS, and 0.71 for non-normal stereoscopic vision for at least one fall, but wide confidence intervals made it difficult to draw firm conclusions about any association. Bifocal or progressive spectacles were worn by 71% with no significant difference between fallers and nonfallers (P=0.078). CONCLUSION: Even though ~40% of the total sample had experienced one or more falls, the only visual function test significantly associated with falls were VA better eye, lack of stereoscopic vision, and recurrent falls. Our results suggest that there may be more powerful predictors of falling than decreased visual ability.

19.
Appl Ergon ; 55: 149-155, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26995045

RESUMEN

To design accessibly, designers need good, relevant population data on visual abilities. However, currently available data often focuses on clinical vision measures that are not entirely relevant to everyday product use. This paper presents data from a pilot survey of 362 participants in the UK, covering a range of vision measures of particular relevance to product design. The results from the different measures are compared, and recommendations are given for relative text sizes to use in different situations. The results indicate that text needs to be 17-18% larger for comfortable rather than perceived threshold viewing, and a further 20% larger when users are expected to wear their everyday vision setup rather than specific reading aids.


Asunto(s)
Ergonomía , Análisis y Desempeño de Tareas , Visión Ocular/fisiología , Percepción Visual , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Encuestas y Cuestionarios , Reino Unido , Pruebas del Campo Visual , Adulto Joven
20.
Res Dev Disabil ; 45-46: 284-99, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26277740

RESUMEN

The purpose of this study is to evaluate whether children with Specific Language Impairment (SLI) have a deficit in processing a sequence of two visual stimuli (S1 and S2) presented at different inter-stimulus intervals and in different spatial locations. In particular, the core of this study is to investigate whether S1 identification is disrupted due to a retroactive interference of S2. To this aim, two experiments were planned in which children with SLI and children with typical development (TD), matched by age and non-verbal IQ, were compared (Experiment 1: SLI n=19; TD n=19; Experiment 2: SLI n=16; TD n=16). Results show group differences in the ability to identify a single stimulus surrounded by flankers (Baseline level). Moreover, children with SLI show a stronger negative interference of S2, both for temporal and spatial modulation. These results are discussed in the light of an attentional processing limitation in children with SLI.


Asunto(s)
Atención/fisiología , Trastornos del Desarrollo del Lenguaje/fisiopatología , Percepción Visual/fisiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Trastornos del Desarrollo del Lenguaje/psicología , Masculino , Estimulación Luminosa/métodos , Factores de Tiempo
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