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Purpose: The aim of this study is to transform optical coherence tomography angiography (OCTA) scans into innovative OCTA graphs, serving as novel biomarkers representing the macular vasculature. Patients and Methods: The study included 90 healthy subjects and 39 subjects with various abnormalities (29 with diabetic retinopathy, 5 with age-related macular degeneration, and 5 with choroid neovascularization). OCTA 5µm macular coronal views (MCVs) were generated for each subject, followed by blood vessel segmentation and skeleton processing. Subsequently, the blood vessel density index, blood vessel skeleton index, and blood vessel tortuosity index were computed. The graphs of each metric were plotted against the axial axes of the OCTA B-scan, representing the integrity of vasculature at successive 5µm macular depths. Results: The results revealed two significant findings. First, the B-scans from OCTA can be transformed into OCTA graphs, yielding three specific OCTA graphs in this study. These graphs provide new biomarkers for assessing the integrity of deep vascular complex (DVC) and superficial vascular complex (SVC) within the macula. Second, a statistically significant difference was observed between normal (n=90) and abnormal (n=39) subjects, with a t-test p-value significantly lower than 0.001. The Mann-Whitney u-test also yielded significant difference but only between the 90 normal and 29 DR subjects. Conclusion: The novel OCTA graphs offer a unique representation of the macula's SVC and DVC, suggesting their potential in aiding physicians in the diagnosis of eye health within OCTA clinics. Further research is warranted to finalize the shape of these newly derived OCTA graphs and establish their clinical relevance and utility.
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Virtual reality (VR) allows us to create visual stimuli that are both immersive and reactive. VR provides many new opportunities in vision science. In particular, it allows us to present wide field-of-view, immersive visual stimuli; for observers to actively explore the environments that we create; and for us to understand how visual information is used in the control of behaviour. In contrast with traditional psychophysical experiments, VR provides much greater flexibility in creating environments and tasks that are more closely aligned with our everyday experience. These benefits of VR are of particular value in developing our theories of the behavioural goals of the visual system and explaining how visual information is processed to achieve these goals. The use of VR in vision science presents a number of technical challenges, relating to how the available software and hardware limit our ability to accurately specify the visual information that defines our virtual environments and the interpretation of data gathered in experiments with a freely moving observer in a responsive environment.
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Realidad Virtual , Visión Ocular , Optometría , Humanos , OftalmologíaRESUMEN
Social vision research, which examines, in part, how humans visually perceive social stimuli, is well-positioned to improve understandings of social inequality. However, social vision research has rarely prioritized the perspectives of marginalized group members. We offer a theoretical argument for diversifying understandings of social perceptual processes by centering marginalized perspectives. We examine (a) how social vision researchers frame their research questions and who these framings prioritize and (b) how perceptual processes (person perception; people perception; perception of social objects) are linked to group membership and thus comprehensively understanding these processes necessitates attention to marginalized perceivers. We discuss how social vision research translates into theoretical advances and to action for reducing negative intergroup consequences (e.g., prejudice). The purpose of this article is to delineate how prioritizing marginalized perspectives in social vision research could develop novel questions, bridge theoretical gaps, and elevate social vision's translational impact to improve outcomes for marginalized groups.
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Lentes , Prejuicio , Humanos , Cambio Social , Feminismo , Percepción SocialRESUMEN
"What is the structure of thought?" is as central a question as any in cognitive science. A classic answer to this question has appealed to a Language of Thought (LoT). We point to emerging research from disparate branches of the field that supports the LoT hypothesis, but also uncovers diversity in LoTs across cognitive systems, stages of development, and species. Our letter formulates open research questions for cognitive science concerning the varieties of rules and representations that underwrite various LoT-based systems and how these variations can help researchers taxonomize cognitive systems.
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Ciencia Cognitiva , Lenguaje , HumanosRESUMEN
Aerial predators, such as the dragonfly, determine the position and movement of their prey even when both are moving through complex, natural scenes. This task is likely supported by a group of neurons in the optic lobe which respond to moving targets that subtend less than a few degrees. These Small Target Motion Detector (STMD) neurons are tuned to both target size and velocity, whilst also exhibiting facilitated responses to targets traveling along continuous trajectories. When presented with a pair of targets, some STMDs generate spiking activity that represent a competitive selection of one target, as if the alternative does not exist (i.e., selective attention). Here, we describe intracellular responses of CSTMD1 (an identified STMD) to the visual presentation of targets embedded within cluttered, natural scenes. We examine CSTMD1 response changes to target contrast, as well as a range of target and background velocities. We find that background motion affects CSTMD1 responses via the competitive selection between features within the natural scene. Here, robust discrimination of our artificially embedded "target" is limited to scenarios when its velocity is matched to, or greater than, the background velocity. Additionally, the background's direction of motion affects discriminability, though not in the manner observed in STMDs of other flying insects. Our results highlight that CSTMD1's competitive responses are to those features best matched to the neuron's underlying spatiotemporal tuning, whether from the embedded target or other features in the background clutter. In many scenarios, CSTMD1 responds robustly to targets moving through cluttered scenes. However, whether this neuronal system could underlie the task of competitively selecting slow moving prey against fast-moving backgrounds remains an open question.
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Digital health technology is increasingly becoming part of the evolution of health services, not only for the innovation of equipment but also in support of health processes. Eye health is one of the areas that most explores this field, being a reference in different segments of digital health and the use of applied technological resources. Thus, the purpose of this review was to analyse and characterize the development of research in digital health applied to vision sciences in the last decade. An exploratory-quantitative review of the research based on studies indexed in the SCOPUS database in the last 10 years, which related aspects of digital health technologies with their use within the vision sciences, was conducted. The research results were filtered, including journal articles and excluding those not directly related to vision. The final sample was categorized and classified according to the technology used, the relationship with eye/visual health and its practical applications. A total of 1069 reports were identified (32.09% published since 2021). "Artificial Intelligence" (77.74%) was the most frequent technological tool cited, and posterior segment (68.10%) most eye structure studied, being diabetic retinopathy (27.88%) the main studied disease. The vast majority have potential for clinical use (93.73%), especially those aimed at supporting decision-making. Technologies in digital health in the vision sciences have had a huge growth in recent years, with emphasis on artificial intelligence applied to the posterior segment, but with a low development of studies aimed at using this technology in primary visual care.
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Retinopatía Diabética , Telemedicina , Humanos , Telemedicina/métodos , Tecnología , Inteligencia ArtificialRESUMEN
Retinal pigment epithelium (RPE), a postmitotic monolayer located between the neuroretina and choroid, supports the retina and is closely associated with vision loss diseases such as age-related macular degeneration (AMD) upon dysfunction. Although environmental stresses are known to play critical roles in AMD pathogenesis and the roles of other stresses have been well investigated, glucose deprivation, which can arise from choriocapillary flow voids, has yet to be fully explored. In this study, we examined the involvement of VEGFR2 in glucose deprivation-mediated cell death and the underlying mechanisms. We found that VEGFR2 levels are a determinant for RPE cell death, a critical factor for dry AMD, under glucose deprivation. RNA sequencing analysis showed that upon VEGFR2 knockdown under glucose starvation, endoplasmic reticulum (ER) stress and unfolded protein response (UPR) are reduced. Consistently, VEGFR2 overexpression increased ER stress under the same condition. Although VEGFR2 was less expressed compared to EGFR1 and c-Met in RPE cells, it could elicit a higher level of ER stress induced by glucose starvation. Finally, downregulated VEGFR2 attenuated the oxidative stress and inflammatory factor expression, two downstream targets of ER stress. Our study, for the first time, has demonstrated a novel role of VEGFR2 in RPE cells under glucose deprivation, thus providing valuable insights into the mechanisms of AMD pathogenesis and suggesting that VEGFR2 might be a potential therapeutic target for AMD prevention, which may impede its progression.
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Clinical trials for conditions affecting the visual system need to not only conform to the guidelines for all clinical trials, but also accommodate the possibility of both eyes of a single patient qualifying for the trial. In this review, I present the interplay of the key components in the design of a clinical trial, along with the modifications or options that may be available for trials addressing ocular conditions. Examples drawn from published reports of the design and results of clinical trials of ocular conditions are provided to illustrate application of the design principles. Current approaches to data analysis and reporting of trials are outlined, and the oversight and regulatory procedures to protect participants in clinical trials are discussed.
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The data set presents data collected by an online questionnaire, applying closed-ended question types (multiple-choice, Likert scale) and questions Skip Logic. Instruments from previous studies in the field of optometry such as Contact Lens User Experience (CLUE Scales), Quality of Life Questionnaire (CLIQ), Quality of Vision (QoV) Questionnaire, did not meet the needs of this study. Therefore, in order to provide a statistically valid and consistent instrument to examine the psychopathological reactions in Contact lens wearers due to COVID-19, a new questionnaire was designed. The steps followed to collect and manage data were, definition of the objectives of the study, questionnaire design, questionnaire pilot testing (validity, reliability, repeatability), data administration and results interpretation. This descriptive survey employed online data collection using an anonymized questionnaire. The questionnaire was made available via an online link on social networks from 28/09/2020 to 11/10/2020. The questionnaire, in order to record the psychopathological reactions in Contact lens wearers due to COVID-19, was structured according to three psychopathological reactions (COVID-RS scales), (a) disorganized behaviors, (b) avoidant behaviors, (c) maladaptive information consumption. Therefore includes, (a) socio-demographic variables such as, (age, gender, educational level, Professional status, geographical area of habitation), (b) Health and Consumer behavior in Contact lens wearers, (c) Perceived risk of infection due to COVID-19 in Contact lens users, with a total of 22 items and maximum completion time 4 min. The survey included 1676 participants, 1037 were Contact Lens users and completed the online questionnaire. Of them, 76.7% (795) were female and 23.3% (242) were male. The educational level of the participants was, 7.5% (8) primary education, 18.9% (197) Secondary education, 57.9% (601) Undergraduate education, 22.3% (231) Postgraduate education. According to the age groups, 68.2% (707) participants were between 18 and 34 years old, 23.4% (278) participants were between 35 and 54 years old, 4.8% (50) participants were between 55 and 74 years old, 0.2% (2) participants were 75 and over. All data were exported to Excel spreadsheets. Only the completed questionnaires were used in the analyses. Data were analyzed using the Statistical Package for Social Sciences (SPSS) software version 24. Cronbach's alpha showed for the group, Health and Consumer behavior in Contact lens wearers (6 items), to reach acceptable reliability α= 0,881. Cronbach's alpha showed for the group, Perceived risk of infection due to COVID-19 in contact lens wearers (6 items), to reach acceptable reliability α= 0,886. The data set can be used to understand the relationship between the perceived risk of Covid-19 infection and contact lens (CL) use, the potential effect of the pandemic in Health and consumer behavior in Contact lens users, to draft a survey strategy and design, to verify results, etc.
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A 2016 Price Waterhouse Cooper Report, commissioned by the Australian Commonwealth Government's Organ and Tissue Authority, indicated that Australia had been meeting its human ocular tissue for transplant needs. It further suggested that Australia should consider exportation as a management strategy for excess tissue. Although we do not seek to discuss how the Price Waterhouse Cooper Report determined that need was being met, nor the potential value of exportation in this article, we propose that Ocular Tissue for Research (OTR), and particularly identification of donors for research, and timely access to fresh domestic tissue, be considered as an alternate or simultaneous surplus management strategy. A robust OTR system could provide long-term domestic support and investment into research and development of therapies in Australia. Such a system would also provide a meaningful donation option for those otherwise unable to donate for transplant. This article attempts to document, for the first time to our knowledge, the current recovery and distribution processes of deceased OTR in Australia. It maps the process steps, identifies the stakeholders and needs, discusses the limitations and barriers, and proposes key policy and practice reform strategies that may assist in improving access to OTR. Translational Relevance: To improve and increase access to human ocular tissue for research, and in turn, advance vision science and clinical application.
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Trasplante de Órganos , Obtención de Tejidos y Órganos , Australia , Humanos , Donantes de TejidosRESUMEN
Crowding has become a hot topic in vision research, and some fundamentals are now widely agreed upon. For the classical crowding task, one would likely agree with the following statements. (1) Bouma's law can be stated, succinctly and unequivocally, as saying that critical distance for crowding is about half the target's eccentricity. (2) Crowding is predominantly a peripheral phenomenon. (3) Peripheral vision extends to at most 90° eccentricity. (4) Resolution threshold (the minimal angle of resolution) increases strongly and linearly with eccentricity. Crowding increases at an even steeper rate. (5) Crowding is asymmetric as Bouma has shown. For that inner-outer asymmetry, the peripheral flanker has more effect. (6) Critical crowding distance corresponds to a constant cortical distance in primary visual areas like V1. (7) Except for Bouma's seminal article in 1970, crowding research mostly became prominent starting in the 2000s. I propose the answer is "not really" or "not quite" to these assertions. So should we care? I think we should, before we write the textbook chapters for the next generation.
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PURPOSE: This study was designed with the aim of providing practitioners with an evidence base to inform their clinical decision making as to when cycloplegic retinoscopy is necessary and when it might be appropriate to forgo. The study aimed to determine the age at which there ceases to be a clinically significant difference between cycloplegic and non-cycloplegic retinoscopy and whether age, refractive error, habitual spectacle wear and accommodation influence the relationship. METHODS: A single examiner carried out cycloplegic and non-cycloplegic retinoscopy on 128 children stratified into four age groups (6-7, 8-9, 10-12 and 12-13 years). Cycloplegia was achieved using 1% cyclopentolate and retinoscopy carried out after 30 min. The examiner was masked to the lenses used and to habitual spectacle wear. Accommodation was assessed using dynamic retinoscopy prior to cycloplegia. RESULTS: Cycloplegic and non-cycloplegic sphere differed significantly (z = -9.18, p < 0.0001). Although the difference decreased significantly as age increased (χ2 = 16.57, p = 0.0009), cycloplegic retinoscopy revealed more hyperopia than non-cycloplegic retinoscopy in all age groups (p < 0.0001). The difference between cycloplegic and non-cycloplegic results was greater where 'high' hyperopia (≥+2.50DS) was present (F1,6 = 12.86, p = 0.0005), and as hyperopia increased the difference increased (Spearman's ρ = 0.55, p < 0.0001). Neither spectacle wear (p = 0.74) nor accommodation (p = 0.08) influenced the difference between spherical measures. Measures of astigmatic error did not differ significantly (z = -1.59, p = 0.11). A non-cycloplegic sphere ≥+1.50DS was relatively sensitive (87%) and specific (96%) at indicating clinically significant hyperopia (≥+2.50D) as revealed by cycloplegic retinoscopy. CONCLUSIONS: Cyclopentolate 1% does not impact the cylindrical component of the retinoscopy result, but reveals significantly more hyperopia in the spherical component, both statistically and clinically in children aged 6-13 years. Differences between cycloplegic and non-cycloplegic sphere increase significantly with increasing hyperopia, independent of spectacle wear and accommodation. A non-cycloplegic retinoscopy result of ≥+1.50DS may be used by practitioners wishing to identify children aged 6-13 years at risk of clinically significant hyperopia (≥+2.50DS), but cycloplegia is required to accurately ascertain the full spherical error.
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Ciclopentolato/administración & dosificación , Midriáticos/administración & dosificación , Errores de Refracción/diagnóstico , Retinoscopía/métodos , Adolescente , Factores de Edad , Niño , Femenino , Humanos , Masculino , Sensibilidad y EspecificidadRESUMEN
Human visual cortex is organized into multiple retinotopic maps. Characterizing the arrangement of these maps on the cortical surface is essential to many visual neuroscience studies. Typically, maps are obtained by voxel-wise analysis of fMRI data. This method, while useful, maps only a portion of the visual field and is limited by measurement noise and subjective assessment of boundaries. We developed a novel Bayesian mapping approach which combines observation-a subject's retinotopic measurements from small amounts of fMRI time-with a prior-a learned retinotopic atlas. This process automatically draws areal boundaries, corrects discontinuities in the measured maps, and predicts validation data more accurately than an atlas alone or independent datasets alone. This new method can be used to improve the accuracy of retinotopic mapping, to analyze large fMRI datasets automatically, and to quantify differences in map properties as a function of health, development and natural variation between individuals.
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Mapeo Encefálico/métodos , Corteza Visual/anatomía & histología , Corteza Visual/fisiología , Adulto , Teorema de Bayes , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana EdadRESUMEN
VisionCite is a database dedicated to the visual sciences. This paid subscription database provides bibliographic information for optometry and ophthalmology-related resources and is maintained by the Illinois College of Optometry (ICO) Library. A sample search is provided, highlighting different features of the newly redesigned database.
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Bases de Datos Factuales , Oftalmología , Optometría , Humanos , Illinois , Bibliotecas Médicas , Visión OcularRESUMEN
Adaptive optics is a relatively new field, yet it is spreading rapidly and allows new questions to be asked about how the visual system is organized. The editors of this feature issue have posed a series of question to scientists involved in using adaptive optics in vision science. The questions are focused on three main areas. In the first we investigate the use of adaptive optics for psychophysical measurements of visual system function and for improving the optics of the eye. In the second, we look at the applications and impact of adaptive optics on retinal imaging and its promise for basic and applied research. In the third, we explore how adaptive optics is being used to improve our understanding of the neurophysiology of the visual system.
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Fenómenos Fisiológicos Oculares , Óptica y Fotónica , Retina/fisiología , Trastornos de la Visión/rehabilitación , Percepción Visual/fisiología , Animales , Humanos , Psicofísica , Trastornos de la Visión/fisiopatología , Visión Ocular/fisiologíaRESUMEN
PURPOSE: To evaluate the intra- and inter-examiner repeatability of cycloplegic retinoscopy in young children aged 4-5 years old. METHODS: Examiner 1 refracted all children in the first sample (n = 108); firstly with masked loose lenses, then using unmasked loose lenses (intra-examiner repeatability). Examiners 1 and 2 refracted all children in the second sample (n = 97) using unmasked loose lenses, blind to the child's refractive error, presence/magnitude of habitual spectacle correction and to each other's findings (inter-examiner repeatability). Refractions were performed on one eye chosen at random. Mean differences, 95% limits of agreement (LOAs) and confidence intervals were calculated for intra- and inter-examiner repeatability of sphere, cylinder and spherical equivalent refraction (SER). RESULTS: Participants had a wide range of refractive errors (-1.50DS to +7.25DS; ≥4.50DC). Mean differences (95% LOAs) were small for both intra- and inter-examiner repeatability [Intra: Sphere 0.00D (-0.85, +0.85D), Cylinder -0.03D (-0.68, +0.62D), SER -0.06D (-0.90, +0.78D); Inter: Sphere -0.08D (-0.92, +0.76D), Cylinder -0.08D (-0.75, +0.59D), SER -0.13D (-0.95, +0.69D). A statistically significant proportional bias was present for intra-examiner repeatability of cylinder (ρ = 0.20, p = 0.04) and SER measurement (ρ = 0.19, p = 0.049). Proportional bias was not present for any other measure (p > 0.12). Examiners agreed on cylinder axis within ±20° in 71% of refractions where astigmatism of -0.75D or higher was present. 80% of intra- and inter-examiner measures fell within ±0.50D for spherical and cylindrical components. CONCLUSIONS: Differences of ±1.00D and ±0.75D or more for spherical and cylindrical measures respectively can be considered significant when performing cycloplegic retinoscopy on young children.
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Midriáticos/farmacología , Refracción Ocular/fisiología , Errores de Refracción/diagnóstico , Retina/diagnóstico por imagen , Retinoscopía/métodos , Preescolar , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Errores de Refracción/fisiopatología , Selección Visual/métodosRESUMEN
OBJECTIVE: Using a bibliometric approach an analysis was made of the scientific publications of Spanish investigators in the area of optometry, from 1974 until 2013. METHODS: The EMBASE database was used for this study, employing optomtr*, optic*, visual, vision, eye*, and ophthalm* as search terms. The most common bibliometric indicators were applied for the selected publications. RESULTS: The number of published articles retrieved for Spain from 1974-2013 was 1,055. The growth of publications was more exponential (R=0.93) than linear (R= 0.71). The doubling time of scientific production was 3.63 years. The level of productivity primarily corresponded to small producers (Transience index of 64%). The collaboration index was 4.4 authors per paper. The majority of the output was generated in academic settings (62.27%). The Bradford core was formed by four journals, in which Optometry and Vision Science accounted for the majority of publications, with 11.85%. CONCLUSIONS: Research in the area of optometry in Spain is in a phase of exponential growth, containing a high level of transient authors, which may indicate either a low productivity or the presence of investigators from other related fields that have published in a sporadic manner in this area. A small number of research groups are responsible for producing the majority of articles, primarily in an academic setting. There is a high concentration of publications in a few journals.
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Bibliometría , Optometría , Bases de Datos Factuales , Humanos , Publicaciones Periódicas como Asunto , Edición , España , Visión OcularRESUMEN
Optogenetics is an innovative technique for optical control of cells. This field has exploded over the past decade or so and has given rise to great advances in neuroscience. A variety of applications both from the basic and applied research have emerged, turning the early ideas into a powerful paradigm for cell biology, neuroscience and medical research. This review aims at highlighting the basic concepts that are essential for a comprehensive understanding of optogenetics and some important biological/biomedical applications. Further, emphasis is placed on advancement in optogenetics-associated light-based methods for controlling gene expression, spatially-controlled optogenetic stimulation and detection of cellular activities.