Browsing by Subject "Visual Acuity"

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    ItemOpen Access
    Age-related preservation of top-down control over distraction in visual search.
    (Experimental aging research, 2010-07) Costello, Matthew C; Madden, David J; Shepler, Anne M; Mitroff, Stephen R; Leber, Andrew B
    Visual search studies have demonstrated that older adults can have preserved or even increased top-down control over distraction. However, the results are mixed as to the extent of this age-related preservation. The present experiment assesses group differences in younger and older adults during visual search, with a task featuring two conditions offering varying degrees of top-down control over distraction. After controlling for generalized slowing, the analyses revealed that the age groups were equally capable of utilizing top-down control to minimize distraction. Furthermore, for both age groups, the distraction effect was manifested in a sustained manner across the reaction time distribution.
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    ItemOpen Access
    Assessment of Macular Microvasculature in Healthy Eyes of Infants and Children Using OCT Angiography.
    (Ophthalmology, 2019-12) Hsu, S Tammy; Ngo, Hoan T; Stinnett, Sandra S; Cheung, Nathan L; House, Robert J; Kelly, Michael P; Chen, Xi; Enyedi, Laura B; Prakalapakorn, S Grace; Materin, Miguel A; El-Dairi, Mays A; Jaffe, Glenn J; Freedman, Sharon F; Toth, Cynthia A; Vajzovic, Lejla
    PURPOSE:To assess macular vasculature in healthy infants and children using OCT angiography (OCTA). DESIGN:Prospective cross-sectional study. PARTICIPANTS:One hundred thirty-five normal maculae of 89 healthy infants and children (mean age, 8.5±5.3 years; range, 9 weeks-17 years) treated at the Duke University Eye Center. METHODS:We imaged 135 maculae of 89 pediatric patients using the standard Spectralis tabletop and investigational Spectralis with Flex module devices, both equipped with investigational OCTA software (Heidelberg Engineering, Heidelberg, Germany). OCT angiography images of the superficial vascular complex (SVC) and deep vascular complex (DVC) were analyzed for foveal avascular zone (FAZ) area and superficial and deep vessel density. We assessed effects of age, gender, race, axial length (AL), and central subfield thickness on FAZ and vessel density. Patients with both eyes imaged were assessed for agreement between the FAZ and vessel densities of the left and right eyes. MAIN OUTCOME MEASURES:The FAZ area, as well as vessel area density (VAD) and vessel length density (VLD) in the SVC and DVC. RESULTS:The FAZ varied significantly with race; white patients showed a significantly smaller FAZ than black patients (mean difference, 0.11 mm2; P = 0.004). The FAZ did not vary with age, gender, or AL (P > 0.05). In the SVC, VAD and VLD varied significantly with age (P < 0.001) and AL (R2 = 0.46; P < 0.001) but not gender (P > 0.05). The SVC VLD was significantly different between races and ethnicities (P = 0.037), but VAD was not (P < 0.05). In the DVC, VAD and VLD also varied significantly with age (P < 0.001) and AL (R2 = 0.46; P < 0.001) but not gender or race (P > 0.05). There was excellent agreement between the right and left eyes for FAZ (intraclass correlation [ICC], 0.97), SVC VLD (ICC, 1.00), and DVC VLD (ICC, 1.00). CONCLUSIONS:Quantitative studies of pediatric perifoveal vasculature should consider age, race, and AL. In eyes with unilateral disease, the perifoveal vasculature in the unaffected eye may be used as a control comparison because there is excellent agreement between eyes.
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    ItemOpen Access
    Baseline Visual Field Findings in the RUSH2A Study: Associated Factors and Correlation With Other Measures of Disease Severity.
    (American journal of ophthalmology, 2020-11) Duncan, Jacque L; Liang, Wendi; Maguire, Maureen G; Audo, Isabelle; Ayala, Allison R; Birch, David G; Carroll, Joseph; Cheetham, Janet K; Esposti, Simona Degli; Durham, Todd A; Erker, Laura; Farsiu, Sina; Ferris, Frederick L; Heon, Elise; Hufnagel, Robert B; Iannaccone, Alessandro; Jaffe, Glenn J; Kay, Christine N; Michaelides, Michel; Pennesi, Mark E; Sahel, José-Alain; Foundation Fighting Blindness Consortium Investigator Group

    Purpose

    To report baseline visual fields in the Rate of Progression in USH2A-related Retinal Degeneration (RUSH2A) study.

    Design

    Cross-sectional study within a natural history study.

    Methods

    Setting: multicenter, international.

    Study population

    Usher syndrome type 2 (USH2) (n = 80) or autosomal recessive nonsyndromic retinitis pigmentosa (ARRP) (n = 47) associated with biallelic disease-causing sequence variants in USH2A.

    Observation procedures

    Repeatability of full-field static perimetry (SP) and between-eye symmetry of kinetic perimetry (KP) were evaluated with intraclass correlation coefficients (ICCs). The association of demographic and clinical characteristics with total hill of vision (VTOT) was assessed with general linear models. Associations between VTOT and other functional and morphologic measures were assessed using Spearman correlation coefficients and t tests.

    Main outcome measures

    VTOT (SP) and III4e isopter area (KP).

    Results

    USH2 participants had more severe visual field loss than ARRP participants (P < .001, adjusting for disease duration, age of enrollment). Mean VTOT measures among 3 repeat tests were 32.7 ± 24.1, 31.2 ± 23.4, and 31.7 ± 23.9 decibel-steradians (intraclass correlation coefficient [ICC] = 0.96). Better VA, greater photopic ERG 30-Hz flicker amplitudes, higher mean microperimetry sensitivity, higher central subfield thickness, absence of macular cysts, and higher III4e seeing area were associated with higher VTOT (all r > .48; P < .05). Mean III4e isopter areas for left (4561 ± 4426 squared degrees) and right eyes (4215 ± 4300 squared degrees) were concordant (ICC = 0.94).

    Conclusions

    USH2 participants had more visual field loss than participants with USH2A-related ARRP, adjusting for duration of disease and age of enrollment. VTOT was repeatable and correlated with other functional and structural metrics, suggesting it may be a good summary measure of disease severity in patients with USH2A-related retinal degeneration.
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    The RUSH2A Study: Best-Corrected Visual Acuity, Full-Field Electroretinography Amplitudes, and Full-Field Stimulus Thresholds at Baseline.
    (Translational vision science & technology, 2020-10-08) Birch, David G; Cheng, Peiyao; Duncan, Jacque L; Ayala, Allison R; Maguire, Maureen G; Audo, Isabelle; Cheetham, Janet K; Durham, Todd A; Fahim, Abigail T; Ferris, Frederick L; Heon, Elise; Huckfeldt, Rachel M; Iannaccone, Alessandro; Khan, Naheed W; Lad, Eleonora M; Michaelides, Michel; Pennesi, Mark E; Stingl, Katarina; Vincent, Ajoy; Weng, Christina Y; Foundation Fighting Blindness Consortium Investigator Group

    Purpose

    The purpose of this study was to evaluate baseline best corrected visual acuity (BCVA), full-field electroretinography (ERG), full-field stimulus thresholds (FST), and their relationship with baseline demographic and clinical characteristics in the Rate of Progression in Usher syndrome type 2 (USH2A)-related Retinal Degeneration (RUSH2A) multicenter study.

    Methods

    Participants had Usher syndrome type 2 (USH2, N = 80) or autosomal recessive nonsyndromic retinitis pigmentosa (ARRP, N = 47) associated with biallelic variants in the USH2A gene. Associations of demographic and clinical characteristics with BCVA, ERG, and FST were assessed with regression models.

    Results

    In comparison to ARRP, USH2 had worse BCVA (median 79 vs. 82 letters; P < 0.001 adjusted for age), lower rod-mediated ERG b-wave amplitudes (median 0.0 vs. 6.6 µV; P < 0.001) and 30 Hz flicker cone-mediated ERG amplitudes (median 1.5 vs. 3.1 µV; P = 0.001), and higher (white, blue, and red) FST thresholds (means [-26, -31, -23 dB] vs. [-39, -45, -28 dB]; P < 0.001 for all stimuli). After adjusting for age, gender, and duration of vision loss, the difference in BCVA between diagnosis groups was attenuated (P = 0.09). Only diagnosis was associated with rod- and cone-mediated ERG parameters, whereas both genders (P = 0.04) and duration of visual loss (P < 0.001) also were associated with FST white stimulus.

    Conclusions

    USH2 participants had worse BCVA, ERG, and FST than ARRP participants. FST was strongly associated with duration of disease; it remains to be determined whether it will be a sensitive measure of progression.

    Translational relevance

    Using standardized research protocols in RUSH2A, measures have been identified to monitor disease progression and treatment response and differentiate features of prognostic relevance between USH2 and ARRP participants with USH2A mutations.
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    Visual abilities distinguish pitchers from hitters in professional baseball.
    (Journal of sports sciences, 2018-01) Klemish, David; Ramger, Benjamin; Vittetoe, Kelly; Reiter, Jerome P; Tokdar, Surya T; Appelbaum, Lawrence Gregory
    This study aimed to evaluate the possibility that differences in sensorimotor abilities exist between hitters and pitchers in a large cohort of baseball players of varying levels of experience. Secondary data analysis was performed on 9 sensorimotor tasks comprising the Nike Sensory Station assessment battery. Bayesian hierarchical regression modelling was applied to test for differences between pitchers and hitters in data from 566 baseball players (112 high school, 85 college, 369 professional) collected at 20 testing centres. Explanatory variables including height, handedness, eye dominance, concussion history, and player position were modelled along with age curves using basis regression splines. Regression analyses revealed better performance for hitters relative to pitchers at the professional level in the visual clarity and depth perception tasks, but these differences did not exist at the high school or college levels. No significant differences were observed in the other 7 measures of sensorimotor capabilities included in the test battery, and no systematic biases were found between the testing centres. These findings, indicating that professional-level hitters have better visual acuity and depth perception than professional-level pitchers, affirm the notion that highly experienced athletes have differing perceptual skills. Findings are discussed in relation to deliberate practice theory.
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    Visual Acuity does not Moderate Effect Sizes of Higher-Level Cognitive Tasks.
    (Experimental aging research, 2016-05) Houston, James R; Bennett, Ilana J; Allen, Philip A; Madden, David J

    Background/study context

    Declining visual capacities in older adults have been posited as a driving force behind adult age differences in higher-order cognitive functions (e.g., the "common cause" hypothesis of Lindenberger & Baltes, 1994, Psychology and Aging, 9, 339-355). McGowan, Patterson, and Jordan (2013, Experimental Aging Research, 39, 70-79) also found that a surprisingly large number of published cognitive aging studies failed to include adequate measures of visual acuity. However, a recent meta-analysis of three studies (La Fleur and Salthouse, 2014, Psychonomic Bulletin & Review, 21, 1202-1208) failed to find evidence that visual acuity moderated or mediated age differences in higher-level cognitive processes. In order to provide a more extensive test of whether visual acuity moderates age differences in higher-level cognitive processes, we conducted a more extensive meta-analysis of topic.

    Methods

    Using results from 456 studies, we calculated effect sizes for the main effect of age across four cognitive domains (attention, executive function, memory, and perception/language) separately for five levels of visual acuity criteria (no criteria, undisclosed criteria, self-reported acuity, 20/80-20/31, and 20/30 or better).

    Results

    As expected, age had a significant effect on each cognitive domain. However, these age effects did not further differ as a function of visual acuity criteria.

    Conclusion

    The current meta-analytic, cross-sectional results suggest that visual acuity is not significantly related to age group differences in higher-level cognitive performance-thereby replicating La Fleur and Salthouse (2014). Further efforts are needed to determine whether other measures of visual functioning (e.g., contrast sensitivity, luminance) affect age differences in cognitive functioning.