40,978 results on '"Vision, Ocular"'
Search Results
2. Dual-Task Exercise for Mild Traumatic Brain Injury (mTBI)
- Published
- 2024
3. Stroboscopic Vision Training in Softball
- Published
- 2024
4. Visual Attention and Eye Movements
- Author
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Jude Mitchell, Assistant Professor
- Published
- 2023
5. Masks and Visual Preferences in the Newborn (BABYMASK)
- Author
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Laboratoire de Psychologie et NeuroCognition
- Published
- 2021
6. Clinical observation of acupuncture treatment for children with accommodative myopia.
- Author
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Zhang, Xiaopeng, Han, Rong, Qiu, Xiaodi, Kong, Xiehe, Cao, Yaojiani, Wang, Xuejun, Zhao, Yue, Zhao, Feng, and Ma, Xiaopeng
- Abstract
Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2023
- Full Text
- View/download PDF
7. Giant jelly bump deposits on therapeutic contact lens: an unusual finding following ptosis surgery
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Ayushi Agarwal, Somasheila I Murthy, Nandini Bothra, and Milind N Naik
- Subjects
Cornea ,Humans ,Female ,General Medicine ,Contact Lenses, Hydrophilic ,Bandages ,Vision, Ocular ,Corneal Diseases - Abstract
The authors report two cases of unusually large deposits on their therapeutic bandage contact lens (BCL) following uneventful surgery for congenital ptosis. The first case presented at 6 weeks with decreased vision, large jelly-bump deposits over the contact lens and sterile corneal infiltrates. The infiltrates rapidly resolved with restoration of vision following contact lens removal and topical antibiotics. The second case presented 2 weeks after surgery with visual loss and similar deposits but with no corneal involvement. Following replacement of BCL and topical lubricants, her vision improved to 20/20. Studies on the role of BCL in ptosis surgery are scarce with literature supporting its use for ocular surface protection and minimising postoperative discomfort. The authors hypothesise impaired blink mechanism as the accelerating factor for this unusual occurrence in the early postoperative period and recommend frequent replacement of the contact lens and a closer follow-up in all these cases.
- Published
- 2024
8. Comparison of Visual Outcomes of Ophthalmic Artery Aneurysms Treated with Microsurgical Clipping and Endovascular Coiling
- Author
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Guangdong Lu, Jaewoo Chung, Jung Cheol Park, Jae Sung Ahn, Byung Duk Kwun, and Deok Hee Lee
- Subjects
aneurysms ,balloon occlusion test ,clipping ,coiling ,ophthalmic artery ,vision, ocular ,Medicine (General) ,R5-920 ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Purpose Post-treatment visual deficit is a major concern associated with both microsurgical clipping and endovascular coiling for the treatment of ophthalmic artery (OphA) aneurysms of the internal carotid artery. We aimed to compare the safety and effectiveness of the 2 modalities. Materials and Methods We retrospectively reviewed and compared the baseline characteristics and postoperative visual and angiographic outcomes of OphA aneurysms treated by clipping or coiling between January 2010 and August 2018 at our hospital. In addition, the balloon occlusion test was performed to evaluate the safety of OphA occlusion. Results This study included 56 aneurysms treated by clipping and 82 aneurysms treated by coiling. Both the immediate and follow-up rates of incomplete aneurysm occlusion were comparable between the 2 groups (21.4% vs. 22.0%; 24.4% vs. 23.6%). The incidence of post-treatment visual deficits was higher in the clipping group than in the coiling group (16.1% vs. 2.4%; P=0.010). We observed total ipsilateral OphA occlusion in 6 patients and near occlusion in 3 patients during endovascular coiling; however, only 1 patient with near OphA occlusion showed a post-treatment visual field defect. Conclusion OphA aneurysms treated by endovascular coiling exhibited an aneurysm occlusion rate similar to that of microsurgical clipping with fewer post-treatment visual deficits. The total occlusion of OphA with adequate collaterals did not cause post-treatment visual deficits.
- Published
- 2022
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9. Pupillary response in air force and air defence pilots when exposed to Gz+ acceleration
- Author
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Ranđelović Danijela, Srećković Sunčica, Šarenac-Vulović Tatjana, and Petrović Nenad
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acceleration ,aerospace medicine ,centrifugation ,pilots ,reflex, pupillary ,vision, ocular ,vision tests ,Medicine (General) ,R5-920 - Abstract
Background/Aim. In aviation, visual functions are important for the simultaneous monitoring the instrument panel and signs in the environment. From the very beginning of the development of aviation, visual function has been deemed particularly important. The effect of +Gz acceleration on the organ of vision is very significant for investigations in aviation medicine. Visual functions are the most important of all sensory functions where flight safety and quality of flight performance are concerned. High acceleration onset rates may cause changes in pupil diameter of a pilot with significant changes in visual function. However, it is important to maintain visual functions due to rapid pilotʼs orientation in the space. The aim of this study was to establish whether there was any pupillary response in Air Force and Air Defence pilots or changes in pupil diameter when exposed to +Gz acceleration in the human centrifuge. Меthods. The study was conducted on 65 Air Force and Air Defence pilots aged from 28 to 45 years of age. The pilots were exposed to an acceleration of +5.5Gz to +7Gz. We examined the obtained differences in pupil diameter according to a rate of acceleration in the period of three consecutive days. Rеsults. Changes in pupil diameter during the pilot’s exposure to different high values of acceleration in the course of three days, measured before, during and after the exposure, generated statistically significant results. No statistically significant differences in pupil diameter were noticed when the pilots were exposed to the same values of acceleration before the testing on the first, second or third day. During the test, pupil diameter was statistically significantly larger than before the test. Conclusion. Transient changes in pupil diameter occurred in pilots exposed to a +7Gz acceleration. Pilots were able to withstand exposure to a +5.5Gz acceleration, without any major changes in the pupil diameter. Physiological training of pilots in the human centrifuge mimicking conditions of real G acceleration, improves tolerance to acceleration, which is important for flight safety.
- Published
- 2022
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10. Regulatory effect of acupuncture on electrical activity level of optic cortex in amblyopia model rats.
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Hao, Xiaolu, Ma, Chongbing, Zhou, Na, Sun, Yaling, Zhu, Tiantian, Sun, Yan, Wang, Jue, Yan, Xingke, and Liu, Anguo
- Abstract
Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
- Full Text
- View/download PDF
11. Comparative genomics sheds new light on the convergent evolution of infrared vision in snakes.
- Author
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Zou D, Huang S, Tian S, Kilunda FK, Murphy RW, Dahn HA, Zhou Y, Lee PS, and Chen JM
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- Animals, Boidae genetics, Boidae physiology, Snakes genetics, Evolution, Molecular, Vision, Ocular, Biological Evolution, Phylogeny, Genomics, Infrared Rays
- Abstract
Infrared vision is a highly specialized sensory system that evolved independently in three clades of snakes. Apparently, convergent evolution occurred in the transient receptor potential ankyrin 1 ( TRPA1 ) proteins of infrared-sensing snakes. However, this gene can only explain how infrared signals are received, and not the transduction and processing of those signals. We sequenced the genome of Xenopeltis unicolor , a key outgroup species of pythons, and performed a genome-wide analysis of convergence between two clades of infrared-sensing snakes. Our results revealed pervasive molecular adaptation in pathways associated with neural development and other functions, with parallel selection on loci associated with trigeminal nerve structural organization. In addition, we found evidence of convergent amino acid substitutions in a set of genes, including TRPA1 and TRPM2 . The analysis also identified convergent accelerated evolution in non-coding elements near 12 genes involved in facial nerve structural organization and optic nerve development. Thus, convergent evolution occurred across multiple dimensions of infrared vision in vipers and pythons, as well as amino acid substitutions, non-coding elements, genes and functions. These changes enabled independent groups of snakes to develop and use infrared vision.
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- 2024
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12. Ocular Ischemic Syndrome and the Role of Carotid Artery Revascularization.
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Suhail S, Tallarita T, Kanzafarova I, Lau J, Mansukhani S, Olatunji S, Calvin AD, Moustafa B, Manz J, and Sen I
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- Humans, Treatment Outcome, Aged, Male, Female, Time Factors, Risk Factors, Ischemia physiopathology, Ischemia surgery, Ischemia diagnosis, Ischemia therapy, Ischemia etiology, Middle Aged, Vision Disorders etiology, Vision Disorders physiopathology, Endovascular Procedures adverse effects, Syndrome, Recovery of Function, Vision, Ocular, Aged, 80 and over, Endarterectomy, Carotid adverse effects, Carotid Stenosis diagnostic imaging, Carotid Stenosis surgery, Carotid Stenosis complications, Carotid Stenosis therapy, Stents
- Abstract
Background: Ocular ischemic syndrome (OIS) is a rare presentation of atherosclerotic carotid artery stenosis that can result in permanent visual loss. This severely disabling syndrome remains under diagnosed and undertreated due to lack of awareness; especially since it requires expedited multidisciplinary care. The relevance of early diagnosis and treatment is increasing due to an increasing prevalence of cerebrovascular disease., Methods: The long-term visual and cerebrovascular outcomes following intervention for nonarteritic OIS, remain poorly described and were the objective of this concise review. We conducted a PubMed search to include all English language publications (cohort studies and case reports) between 2002 and 2023., Results: A total of 33 studies (479 patients) report the outcomes of treatment of OIS with carotid endarterectomy (CEA, 304 patients, 19 studies), and carotid artery stenting (CAS, 175 patients, 14 studies). Visual outcomes were improved or did not worsen in 447 patients (93.3%). No periprocedural stroke was reported. Worsening visual symptoms were rare (35 patients, 7.3%); they occurred in the immediate postoperative period secondary to ocular hypoperfusion (3 patients) and in the late postoperative period due to progression of systemic atherosclerotic disease. Symptomatic recurrence due to recurrent stenosis after CEA was reported in 1 patient (0.21%); this was managed successfully with CAS. None of these studies report the results of transcarotid artery revascularization, the long-term operative outcome or stroke rate., Conclusions: OIS remains to be an underdiagnosed condition. Early diagnosis and prompt treatment are crucial in reversal or stabilization of OIS symptoms. An expedited multidisciplinary approach between vascular surgery and ophthalmology services is necessary to facilitate timely treatment and optimize outcome. If diagnosed early, both CEA and CAS have been associated with visual improvement and prevention of progressive visual loss., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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13. [Practical Application of Intelligent Vision Measurement System Based on Deep Learning].
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Hu R, Sun D, Shi G, and Pan A
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- Humans, Blinking, Dry Eye Syndromes physiopathology, Vision, Ocular, Deep Learning
- Abstract
To comprehensively assess the true visual function of clinical dry eye patients and the comprehensive impact of blinking characteristics on functional vision of the human eye, an intelligent vision measurement system has been designed and developed to detect and analyze blinks from the side. The system employs deep learning keypoint recognition technology to analyze eyelid features from a lateral perspective. It presents the data of identified key points for the upper and lower eyelids in a line chart format and annotates the trough of each blink. By setting benchmark values, the system automatically calculates the proportion of complete and incomplete blinks in the tested individuals. The results indicate that the system is stable in performance and accurate in measurement, successfully achieving the anticipated design objectives. It thereby provides reliable technical support for future clinical applications.
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- 2024
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14. Glaucoma Rehabilitation using ElectricAI Transcranial Stimulation (GREAT)-study protocol for randomized controlled trial using combined perceptual learning and transcranial electrical stimulation for vision enhancement.
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Jia S, Mei X, Chen L, Chan LH, Tsang C, Suen V, Li T, Zaw MW, Liu A, Thompson B, Sabel B, Woo G, Leung CKS, Yip SP, Chang DHF, and Cheong AMY
- Subjects
- Humans, Double-Blind Method, Visual Fields physiology, Randomized Controlled Trials as Topic, Treatment Outcome, Male, Middle Aged, Learning, Aged, Female, Vision, Ocular, Visual Perception, Recovery of Function, Transcranial Direct Current Stimulation methods, Quality of Life, Glaucoma physiopathology, Glaucoma rehabilitation
- Abstract
Background: Glaucoma patients with irreversible visual field loss often experience decreased quality of life, impaired mobility, and mental health challenges. Perceptual learning (PL) and transcranial electrical stimulation (tES) have emerged as promising interventions for vision rehabilitation, showing potential in restoring residual visual functions. The Glaucoma Rehabilitation using ElectricAI Transcranial stimulation (GREAT) project aims to investigate whether combining PL and tES is more effective than using either method alone in maximizing the visual function of glaucoma patients. Additionally, the study will assess the impact of these interventions on brain neural activity, blood biomarkers, mobility, mental health, quality of life, and fear of falling., Methods: The study employs a three-arm, double-blind, randomized, superiority-controlled design. Participants are randomly allocated in a 1:1:1 ratio to one of three groups receiving: (1) real PL and real tES, (2) real PL and sham tES, and (3) placebo PL and sham tES. Each participant undergoes 10 sessions per block (~ 1 h each), with a total of three blocks. Assessments are conducted at six time points: baseline, interim 1, interim 2, post-intervention, 1-month post-intervention, and 2-month post-intervention. The primary outcome is the mean deviation of the 24-2 visual field measured by the Humphrey visual field analyzer. Secondary outcomes include detection rate in the suprathreshold visual field, balance and gait functions, and electrophysiological and biological responses. This study also investigates changes in neurotransmitter metabolism, biomarkers, self-perceived quality of life, and psychological status before and after the intervention., Discussion: The GREAT project is the first study to assess the effectiveness of PL and tES in the rehabilitation of glaucoma. Our findings will offer comprehensive assessments of the impact of these treatments on a wide range of brain and vision-related metrics including visual field, neural activity, biomarkers, mobility, mental health, fear of falling, and quality of life., Trial Registration: ClinicalTrials.gov NCT05874258 . Registered on May 15, 2023., (© 2024. The Author(s).)
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- 2024
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15. Digest: How environmental light conditions shape the evolution of visual systems in birds.
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Washington TM
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- Animals, Light, Environment, Birds physiology, Birds genetics, Biological Evolution, Vision, Ocular
- Abstract
How do varying environmental light conditions influence the evolution of avian visual systems? Fröhlich et al. (2024) demonstrate that nocturnal birds evolved broader corneas and slightly longer axial lengths than their diurnal counterparts, increasing light capture efficiency. Nocturnal species also tended to maintain or reduce the size of brain regions responsible for vision, i.e., the optic tectum and the visual wulst. These results highlight adaptive trends in nocturnal species, where evolutionary improvement in low-light performance of eyes may be accompanied by compromised brain function., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE). All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
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- 2024
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16. Light conditions and the evolution of the visual system in birds.
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Fröhlich A, Ducatez S, Neˇmec P, and Sol D
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- Animals, Light, Phylogeny, Visual Acuity, Superior Colliculi physiology, Birds physiology, Birds genetics, Biological Evolution, Vision, Ocular
- Abstract
Despite vision being an essential sense for many animals, the intuitively appealing notion that the visual system has been shaped by environmental light conditions is backed by insufficient evidence. Based on a comprehensive phylogenetic comparative analysis of birds, we investigate if exposure to different light conditions might have triggered evolutionary divergence in the visual system through pressures on light sensitivity, visual acuity, and neural processing capacity. Our analyses suggest that birds that have adopted nocturnal habits evolved eyes with larger corneal diameters and, to a lesser extent, longer axial length than diurnal species. However, we found no evidence that sensing and processing organs were selected together, as observed in diurnal birds. Rather than enlarging the processing centers, we found a tendency among nocturnal species to either reduce or maintain the size of the two main brain centers involved in vision-the optic tectum and the wulst. These results suggest a mosaic pattern of evolution, wherein optimization of the eye optics for efficient light capture in nocturnal species may have compromised visual acuity and central processing capacity., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE). All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
- Published
- 2024
- Full Text
- View/download PDF
17. The after-effects of occupational whole-body vibration on human cognitive, visual, and motor function: A systematic review.
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Halmai B, Holsgrove TP, Vine SJ, Harris DJ, and Williams GKR
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- Humans, Vision, Ocular, Cognition, Occupational Exposure adverse effects, Postural Balance physiology, Vibration adverse effects
- Abstract
Whole-body vibration (WBV) is prevalent in labour-related activities and can have adverse effects on the health and performance of the individuals exposed. However, evidence regarding the extent to which human functionality is affected following occupational WBV exposure has not been collated. The current systematic review sought to synthesize existing literature and assess the strength and direction of evidence regarding the acute after-effects of occupational WBV exposure on cognition, visual function, postural stability, and motor control. We conducted a comprehensive search of AMED, CINAHL, MEDLINE, PubMED, Psychology and Behavioural Sciences Collection, SPORTDiscus, APA PsychInfo, Cochrane Library, EMBASE, HMIC, Global Health, ProQuest Central, Scopus, Web of Science, and the US National Technical Information Service on April 26, 2023. Studies that quantified vibration exposure and measured acute changes in cognition, visual function, postural stability, and motor control from baseline to post-vibration were considered without date restriction. Out of the 2663 studies identified, 32 were eligible for inclusion. Based on the Risk of Bias in Non-Randomized Studies of Exposure (ROBINS-E) tool, the studies demonstrated low (66%), moderate (25%) and high risk of bias (9%). The findings indicate that after exposure to WBV, postural stability either deteriorates or remains unchanged. Inconsistent effects of WBV on cognition were reported, while visual function and motor control showed no pronounced changes following WBV. This might be attributed to assessment limitations such as learning effects in neuropsychological and motor tasks, and non-functional measures of vision employed. There was a lack of consistency in the characterization of vibration exposure and the assessment of associated effects on functional performance. Current evidence is therefore insufficient to provide definitive guidance for updating occupational health and safety regulations regarding WBV. However, this review highlights the potential for WBV to jeopardize post-exposure human performance and, consequently, safety. The completion of the review was supported by a UKRI EPSRC training grant. The review has been registered on PROSPERO (ref CRD42023391075)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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18. The Visual Brain and Peripheral Reading and Writing Disorders : A Guide to Visual System Dysfuntion for Speech-Language Pathologists
- Author
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Heidi Heeringa and Heidi Heeringa
- Subjects
- Visual Perception, Language Disorders--diagnosis, Visual Pathways, Vision, Ocular, Language Disorders--therapy
- Abstract
The Visual Brain and Peripheral Reading and Writing Disorders: A Guide to Visual System Dysfunction for Speech-Language Pathologists familiarizes the reader with the complex workings of the human visual system, the motor and sensory components of normal vision as they relate to the recognition of letters and words, and to the acquisition and rehabilitation of reading and writing. This text brings together findings from the neuropsychological, neurooptometric, neurolinguistic, occupational therapy, and speech-language pathology literature on acquired visual system impairment from the past 20+ years, and the ways visual system dysfunction impacts reading, writing, and cognition. Chapters Include: •Review of structural elements of the eye, the cortical and subcortical structures of the visual brain, and the motor and sensory components of normal vision •The distinct functions of the three primary visual pathways (central, peripheral and retinotectal) and how they relate to reading and writing •Review of five formal tests of reading and writing that are designed or may be adapted to assess peripheral reading and writing disorders •And much more! A few of the features inside: •Figures illustrating the various components of the visual brain that are engaged when we read and write •Information on visual system deficits in left hemisphere lesions with and without aphasia •Detailed descriptions of peripheral reading disorders and associated error patterns •Diagnostic criteria for three different types of neglect (viewer-centered, stimulus-centered, object-centered) •Description of treatment materials and methods suited to clients with acquired dyslexia due to visual system dysfunction The Visual Brain and Peripheral Reading and Writing Disorders explains the heterogenous nature of peripheral reading and writing disorders, describes the association between visual motor and sensory dysfunction and the acquired dyslexias, and provides the speech-language pathologist with specific guidelines regarding the assessment and treatment of reading and writing disorders associated with visual system dysfunction.
- Published
- 2019
19. Physiological changes in vision during aging: perceptions of older adults and healthcare providers
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Tattiana Dias de Carvalho Cordeiro, Luípa Michele Silva, Edilene Araujo Monteiro, Maria de Lourdes de Farias Pontes, Francine Golgheto Casemiro, and Rosalina Aparecida Partezani Rodrigues
- Subjects
geriatric nursing ,aged ,vision, ocular ,aging ,Nursing ,RT1-120 - Abstract
Objective. To identify the physiological changes in older adults’ vision during the aging process. Methods. An exploratory, descriptive study with a qualitative approach was conducted with 20 older adults and six healthcare providers who worked with older adults in João Pessoa, Paraíba (Brazil). The Focus Group Technique was used for data collection, with the collected information subsequently being submitted to Inductive Thematic Analysis using textual analysis software. Results. The physiological changes related to vision were described by both the older adults and healthcare providers using the following words: vision, difficulty; see; cataract; glasses; surgery; more; age; eye; and no. These terms represent declines in vision resulting from advancing age which significantly modify the daily lives of older adults and their families. Conclusion. The perception of the older adults and the healthcare providers who care for them regarding the physiological changes in vision throughout the aging process shows that the loss of visual acuity significantly affects the daily life of older adults and their families.
- Published
- 2021
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20. Recent advances in insect vision in a 3D world: looming stimuli and escape behaviour.
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Rind FC
- Subjects
- Animals, Motion Perception, Diptera physiology, Grasshoppers physiology, Insecta physiology, Vision, Ocular, Escape Reaction
- Abstract
Detecting looming motion directly towards the insect is vital to its survival. Looming detection in two insects, flies and locusts, is described and contrasted. Pathways using looming detectors to trigger action and their topographical layout in the brain is explored in relation to facilitating behavioural selection. Similar visual stimuli, such as looming motion, are processed by nearby glomeruli in the brain. Insect-inspired looming motion detectors are combined to detect and avoid collision in different scenarios by robots, vehicles and unmanned aerial vehicle (UAV)s., Competing Interests: Declaration of Competing Interest None, (Copyright © 2024 The Author. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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21. Light flicker boosts zebrafish visual recovery after injury.
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Ferreira J
- Subjects
- Animals, Light, Vision, Ocular, Recovery of Function, Photic Stimulation, Zebrafish physiology
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- 2024
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22. Functional differences between the extraordinary eyes of deep-sea hyperiid amphipods.
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Jessop AL, Bagheri ZM, Partridge JC, Osborn KJ, and Hemmi JM
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- Animals, Ecosystem, Visual Fields, Eye anatomy & histology, Vision, Ocular, X-Ray Microtomography, Amphipoda physiology, Amphipoda anatomy & histology
- Abstract
The ocean's midwater is a uniquely challenging yet predictable and simple visual environment. The need to see without being seen in this dim, open habitat has led to extraordinary visual adaptations. To understand these adaptations, we compared the morphological and functional differences between the eyes of three hyperiid amphipods- Hyperia galba , Streetsia challengeri and Phronima sedentaria . Combining micro-CT data with computational modelling, we mapped visual field topography and predicted detection distances for visual targets viewed in different directions through mesopelagic depths. Hyperia 's eyes provide a wide visual field optimized for spatial vision over short distances, while Phronima 's and Streetsia 's eyes have the potential to achieve greater sensitivity and longer detection distances using spatial summation. These improvements come at the cost of smaller visual fields, but this loss is compensated for by a second pair of eyes in Phronima and by behaviour in Streetsia . The need to improve sensitivity while minimizing visible eye size to maintain crypsis has likely driven the evolution of hyperiid eye diversity. Our results provide an integrative look at how these elusive animals have adapted to the unique visual challenges of the mesopelagic.
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- 2024
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23. Vision matters for shape representation: Evidence from sculpturing and drawing in the blind.
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Tian S, Chen L, Wang X, Li G, Fu Z, Ji Y, Lu J, Wang X, Shan S, and Bi Y
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- Humans, Vision, Ocular, Touch, Blindness psychology, Touch Perception
- Abstract
Shape is a property that could be perceived by vision and touch, and is classically considered to be supramodal. While there is mounting evidence for the shared cognitive and neural representation space between visual and tactile shape, previous research tended to rely on dissimilarity structures between objects and had not examined the detailed properties of shape representation in the absence of vision. To address this gap, we conducted three explicit object shape knowledge production experiments with congenitally blind and sighted participants, who were asked to produce verbal features, 3D clay models, and 2D drawings of familiar objects with varying levels of tactile exposure, including tools, large nonmanipulable objects, and animals. We found that the absence of visual experience (i.e., in the blind group) led to stronger differences in animals than in tools and large objects, suggesting that direct tactile experience of objects is essential for shape representation when vision is unavailable. For tools with rich tactile/manipulation experiences, the blind produced overall good shapes comparable to the sighted, yet also showed intriguing differences. The blind group had more variations and a systematic bias in the geometric property of tools (making them stubbier than the sighted), indicating that visual experience contributes to aligning internal representations and calibrating overall object configurations, at least for tools. Taken together, the object shape representation reflects the intricate orchestration of vision, touch and language., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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24. Retinal response to light exposure in BEST1-mutant dogs evaluated with ultra-high resolution OCT.
- Author
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Wu V, Swider M, Sumaroka A, Dufour VL, Vance JE, Aleman TS, Aguirre GD, Beltran WA, and Cideciyan AV
- Subjects
- Dogs, Animals, Retinal Cone Photoreceptor Cells, Vision, Ocular, Tomography, Optical Coherence, Retina
- Abstract
Mutations in BEST1 cause an autosomal recessive disease in dogs where the earliest changes localize to the photoreceptor-RPE interface and show a retina-wide micro-detachment that is modulated by light exposure. The purpose of this study was to define the spatial and temporal details of the outer retina and its response to light with ultra-high resolution OCT across a range of ages and with different BEST1 mutations. Three retinal regions were selected in each eye: near the fovea-like area, near the optic nerve, both in the tapetal area, and inferior to the optic nerve in the non-tapetal area. The OS+ slab thickness was defined between the peak near the junction of inner and outer segments (IS/OS) and the transition between basal RPE, Bruch membrane, choriocapillaris and proximal tapetum (RPE/T). In wildtype (WT) dogs, two tapetal regions showed additional hyperscattering OCT peaks within the OS+ slab likely representing cone and rod outer segment tips (COST and ROST). The inferior non-tapetal region of WT dogs had only one of these peaks, likely ROST. In dogs with BEST1 mutations, all three locations showed a single peak, likely suggesting optical silence of COST. Light-dependent expansion of the micro-detachment by about 10 um was detectable in both tapetal and non-tapetal retina across all ages and BEST1 mutations., Competing Interests: Declaration of competing interest GDA, WAB, and AVC are listed as co-inventors on patent applications related to treating bestrophinopathies., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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25. Developmental changes in the visual, haptic, and bimodal perception of geometric angles.
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Holmes CA, Cooney SM, Dempsey P, and Newell FN
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- Adult, Child, Humans, Adolescent, Haptic Technology, Vision, Ocular, Spatial Learning, Knowledge, Visual Perception, Touch Perception
- Abstract
Geometrical knowledge is typically taught to children through a combination of vision and repetitive drawing (i.e. haptics), yet our understanding of how different spatial senses contribute to geometric perception during childhood is poor. Studies of line orientation suggest a dominant role of vision affecting the calibration of haptics during development; however, the associated multisensory interactions underpinning angle perception are unknown. Here we examined visual, haptic, and bimodal perception of angles across three age groups of children: 6 to 8 years, 8 to 10 years, and 10 to 12 years, with age categories also representing their class (grade) in primary school. All participants first learned an angular shape, presented dynamically, in one of three sensory tracing conditions: visual only, haptic only, or bimodal exploration. At test, which was visual only, participants selected a target angle from four possible alternatives with distractor angle sizes varying relative to the target angle size. We found a clear improvement in accuracy of angle perception with development for all learning modalities. Angle perception in the youngest group was equally poor (but above chance) for all modalities; however, for the two older child groups, visual learning was better than haptics. Haptic perception did not improve to the level of vision with age (even in a comparison adult group), and we found no specific benefit for bimodal learning over visual learning in any age group, including adults. Our results support a developmental increment in both spatial accuracy and precision in all modalities, which was greater in vision than in haptics, and are consistent with previous accounts of cross-sensory calibration in the perception of geometric forms., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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26. Optical characterization and through-focus performance of two advanced monofocal intraocular lenses.
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Salgado-Borges J, Borges A, Ferreira I, González-Méijome JM, and Faria-Ribeiro M
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- Humans, Prospective Studies, Prosthesis Design, Vision, Ocular, Visual Acuity, Patient Satisfaction, Lenses, Intraocular, Phacoemulsification
- Abstract
Purpose: To compare the refractive power profile, subjective depth-of-field and objective optical quality of two advanced monofocal intraocular lenses (IOLs) designed to improve intermediate vision., Methods: This prospective study evaluated forty-six eyes of twenty-three patients, aged 54-68 years, binocularly implanted with two monofocal enhanced intraocular lenses (IOLs), the Tecnis Eyhance and the Physiol Isopure. Subjective through-focus visual acuity curves were obtained by placing trial lenses in front of the eye while wearing its best spherical-cylindrical correction for distance. Objective optical quality was defined as the area under the modulation transfer function, calculated from the wavefront maps measured with a high-resolution aberrometer. The optical design of both lenses was compared based on their refractive power profiles measured with the lenses immersed in saline solution., Results: Both lenses have progressive aspherical geometries, in which the sagittal power decreases rapidly from the center to the edge of the optical zone. Mean monocular through-focus curves show a best corrected distance visual acuity of - 0.02 logMAR with both lenses. Through-focus visual acuity was marginally higher for the Eyhance, with a difference of 1 letter at the defocus position of - 0.5D and 3 letters between - 1.0D and - 2.0D. Objective assessment of optical quality revealed only a difference of about 2 points in MTF area at distance., Conclusion: Both IOLs use a similar approach to improve intermediate vision. The Eyhance showed marginally better subjective performance than the Isopure at the target vergences between - 1.00D and - 2.00D, although these results did not reach statistical significance and were not replicated by the objective findings., (© 2023. The Author(s).)
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- 2024
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27. Mechanisms of cone sensitivity loss in retinitis pigmentosa.
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Simunovic MP and Mammo Z
- Subjects
- Humans, Dark Adaptation, Visual Fields, Vision, Ocular, Visual Field Tests methods, Electroretinography, Retinal Cone Photoreceptor Cells, Retinitis Pigmentosa diagnosis
- Abstract
Purpose: To explore the mechanisms of cone sensitivity loss in retinitis pigmentosa by combining two-colour perimetry with threshold versus intensity (tvi) testing., Methods: Seven subjects with autosomal recessive retinitis pigmentosa and 10 normal subjects were recruited and underwent perimetric testing of one eye using 480- and 640-nm Goldman size V targets presented under scotopic conditions (no background illumination) and against a white background ranging in luminance from -1.5 to 2 log cd m
-2 in 0.5 log cd m-2 steps. Data were fitted with tvi functions of the form logT = logT0 + log ((A + A0 )/A0 )n , where T is the threshold, T0 is the absolute threshold, A is the background intensity, A0 is the 'dark-light' constant and n is a gain constant., Results: Reliable tvi functions could not be obtained within the region of the visual field corresponding to loss of the ellipsoid zone on optical coherence tomography. At fixation, changes in both T0 and A0 were observed, consistent with a d1 mechanism loss, which resulted in an upwards and rightwards shift of the tvi function. Losses at [±3°, ±3°] demonstrated changes in T0 , consistent with a d3 mechanism loss, resulting in an upwards translation of the tvi curve., Conclusions: Although the absolute cone threshold was elevated at each location, shifts in the tvi function (so-called d1 mechanism loss) at fixation minimise threshold elevation in the presence of white adapting backgrounds, such as those typically employed in standard two-colour perimetry. At more peripheral testing locations, changes in threshold occurred independent of background luminance (so-called d3 mechanism loss). These findings suggest that backgrounds which selectively adapt rods while maintaining cones at, or near, absolute threshold may be preferable to conventional two-colour perimetry for assessing loss of cone sensitivity, especially at the point of fixation., (© 2024 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)- Published
- 2024
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28. A multimodal virtual vision platform as a next-generation vision system for a surgical robot.
- Author
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Kim YG, Lee JH, Shim JW, Rhee W, Kim BS, Yoon D, Kim MJ, Park JW, Jeong CW, Yang HK, Cho M, and Kim S
- Subjects
- Humans, User-Computer Interface, Vision, Ocular, Robotics, Robotic Surgical Procedures methods, Virtual Reality
- Abstract
Robot-assisted surgery platforms are utilized globally thanks to their stereoscopic vision systems and enhanced functional assistance. However, the necessity of ergonomic improvement for their use by surgeons has been increased. In surgical robots, issues with chronic fatigue exist owing to the fixed posture of the conventional stereo viewer (SV) vision system. A head-mounted display was adopted to alleviate the inconvenience, and a virtual vision platform (VVP) is proposed in this study. The VVP can provide various critical data, including medical images, vital signs, and patient records, in three-dimensional virtual reality space so that users can access medical information simultaneously. An availability of the VVP was investigated based on various user evaluations by surgeons and novices, who executed the given tasks and answered questionnaires. The performances of the SV and VVP were not significantly different; however, the craniovertebral angle of the VVP was 16.35° higher on average than that of the SV. Survey results regarding the VVP were positive; participants indicated that the optimal number of displays was six, preferring the 2 × 3 array. Reflecting the tendencies, the VVP can be a neoconceptual candidate to be customized for medical use, which opens a new prospect in a next-generation surgical robot., (© 2024. The Author(s).)
- Published
- 2024
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29. Prior visual experience increases children's use of effective haptic exploration strategies in audio-tactile sound-shape correspondences.
- Author
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Cao S, Kelly J, Nyugen C, Chow HM, Leonardo B, Sabov A, and Ciaramitaro VM
- Subjects
- Child, Humans, Touch, Sound, Emotions, Haptic Technology, Vision, Ocular
- Abstract
Sound-shape correspondence refers to the preferential mapping of information across the senses, such as associating a nonsense word like bouba with rounded abstract shapes and kiki with spiky abstract shapes. Here we focused on audio-tactile (AT) sound-shape correspondences between nonsense words and abstract shapes that are felt but not seen. Despite previous research indicating a role for visual experience in establishing AT associations, it remains unclear how visual experience facilitates AT correspondences. Here we investigated one hypothesis: seeing the abstract shapes improve haptic exploration by (a) increasing effective haptic strategies and/or (b) decreasing ineffective haptic strategies. We analyzed five haptic strategies in video-recordings of 6- to 8-year-old children obtained in a previous study. We found the dominant strategy used to explore shapes differed based on visual experience. Effective strategies, which provide information about shape, were dominant in participants with prior visual experience, whereas ineffective strategies, which do not provide information about shape, were dominant in participants without prior visual experience. With prior visual experience, poking-an effective and efficient strategy-was dominant, whereas without prior visual experience, uncategorizable and ineffective strategies were dominant. These findings suggest that prior visual experience of abstract shapes in 6- to 8-year-olds can increase the effectiveness and efficiency of haptic exploration, potentially explaining why prior visual experience can increase the strength of AT sound-shape correspondences., (Copyright © 2023 Elsevier Inc. All rights reserved.)
- Published
- 2024
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30. A clinico-anatomical dissection of the magnocellular and parvocellular pathways in a patient with the Riddoch syndrome.
- Author
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Beyh A, Rasche SE, Leff A, Ffytche D, and Zeki S
- Subjects
- Humans, Male, Hallucinations, Magnetic Resonance Imaging, Photic Stimulation methods, Vision, Ocular, Visual Pathways physiology, Motion Perception physiology, Visual Cortex physiology
- Abstract
Key Message: The Riddoch syndrome is thought to be caused by damage to the primary visual cortex (V1), usually following a vascular event. This study shows that damage to the anatomical input to V1, i.e., the optic radiations, can result in selective visual deficits that mimic the Riddoch syndrome. The results also highlight the differential susceptibility of the magnocellular and parvocellular visual systems to injury. Overall, this study offers new insights that will improve our understanding of the impact of brain injury and neurosurgery on the visual pathways. The Riddoch syndrome, characterised by the ability to perceive, consciously, moving visual stimuli but not static ones, has been associated with lesions of primary visual cortex (V1). We present here the case of patient YL who, after a tumour resection surgery that spared his V1, nevertheless showed symptoms of the Riddoch syndrome. Based on our testing, we postulated that the magnocellular (M) and parvocellular (P) inputs to his V1 may be differentially affected. In a first experiment, YL was presented with static and moving checkerboards in his blind field while undergoing multimodal magnetic resonance imaging (MRI), including structural, functional, and diffusion, acquired at 3 T. In a second experiment, we assessed YL's neural responses to M and P visual stimuli using psychophysics and high-resolution fMRI acquired at 7 T. YL's optic radiations were partially damaged but not severed. We found extensive activity in his visual cortex for moving, but not static, visual stimuli, while our psychophysical tests revealed that only low-spatial frequency moving checkerboards were perceived. High-resolution fMRI revealed strong responses in YL's V1 to M stimuli and very weak ones to P stimuli, indicating a functional P lesion affecting V1. In addition, YL frequently reported seeing moving stimuli and discriminating their direction of motion in the absence of visual stimulation, suggesting that he was experiencing visual hallucinations. Overall, this study highlights the possibility of a selective loss of P inputs to V1 resulting in the Riddoch syndrome and in hallucinations of visual motion., (© 2024. The Author(s).)
- Published
- 2024
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31. Daily dose-response from short-term monocular deprivation in adult humans.
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Zou L, Zhou C, Hess RF, Zhou J, and Min SH
- Subjects
- Adult, Humans, Sensory Deprivation physiology, Vision, Ocular, Vision, Binocular physiology, Dominance, Ocular, Vision, Monocular physiology, Visual Cortex physiology
- Abstract
Short-term monocular deprivation (MD) shifts sensory eye balance in favour of the previously deprived eye. The effect of MD on eye balance is significant but brief in adult humans. Recently, researchers and clinicians have attempted to implement MD in clinical settings for adults with impaired binocular vision. Although the effect of MD has been studied in detail in single-session protocols, what is not known is whether the effect of MD on eye balance deteriorates after repeated periods of MD (termed 'perceptual deterioration'). An answer to this question is relevant for two reasons. Firstly, the effect of MD (i.e., dose-response) should not decrease with repeated use if MD is to be used therapeutically (e.g., daily for weeks). Second, it bears upon the question of whether the neural basis of the effects of MD and contrast adaptation, a closely related phenomenon, is the same. The sensory change from contrast adaptation depends on recent experience. If the observer has recently experienced the same adaptation multiple times for consecutive days, then the adaptation effect will be smaller because contrast adaptation exhibits perceptual deterioration, so it is of interest to know if the effects of MD follow suit. This study measured the effect of 2-h MD for seven consecutive days on binocular balance of 15 normally sighted adults. We found that the shift in eye balance from MD stayed consistent, showing no signs of deterioration after subjects experienced multiple periods of MD. This finding shows no loss of effectiveness of repeated daily doses of MD if used therapeutically to rebalance binocular vision in otherwise normal individuals. Furthermore, ocular dominance plasticity, which is the basis of the effects of short-term MD, does not seem to share the property of 'perceptual deterioration' with contrast adaptation, suggesting different neural bases for these two related phenomena., (© 2024 College of Optometrists.)
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- 2024
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32. A Spiking Artificial Vision Architecture Based on Fully Emulating the Human Vision.
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Wu Y, Deng W, Li K, Wang X, Liu B, Li J, Chen Z, and Zhang Y
- Subjects
- Humans, Artificial Intelligence, Algorithms, Synapses physiology, Image Processing, Computer-Assisted, Vision, Ocular, Neural Networks, Computer
- Abstract
Intelligent vision necessitates the deployment of detectors that are always-on and low-power, mirroring the continuous and uninterrupted responsiveness characteristic of human vision. Nonetheless, contemporary artificial vision systems attain this goal by the continuous processing of massive image frames and executing intricate algorithms, thereby expending substantial computational power and energy. In contrast, biological data processing, based on event-triggered spiking, has higher efficiency and lower energy consumption. Here, this work proposes an artificial vision architecture consisting of spiking photodetectors and artificial synapses, closely mirroring the intricacies of the human visual system. Distinct from previously reported techniques, the photodetector is self-powered and event-triggered, outputting light-modulated spiking signals directly, thereby fulfilling the imperative for always-on with low-power consumption. With the spiking signals processing through the integrated synapse units, recognition of graphics, gestures, and human action has been implemented, illustrating the potent image processing capabilities inherent within this architecture. The results prove the 90% accuracy rate in human action recognition within a mere five epochs utilizing a rudimentary artificial neural network. This novel architecture, grounded in spiking photodetectors, offers a viable alternative to the extant models of always-on low-power artificial vision system., (© 2024 Wiley‐VCH GmbH.)
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- 2024
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33. [The timing and challenges of early intervention for infantile esotropia].
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Li L and Jiang JJ
- Subjects
- Child, Infant, Humans, Vision, Ocular, Vision, Binocular, China, Face, Oculomotor Muscles surgery, Esotropia surgery
- Abstract
Infantile esotropia is a common ophthalmic disease in children. A lot of clinical and basic research evidence suggests that early surgery enhances sensory and ocular motor development. However, the proper timing of surgery has been debated for decades. In addition, there is more likely instability of deviation in the preoperative evaluation of infants, and even if the patient achieved alignment after surgery, the defects in binocular vision may accompany for a lifetime. This article analyzes the difficulties and key points of early intervention for infantile esotropia, aiming to provide scientific ideas for the early treatment of children with infantile esotropia in China.
- Published
- 2024
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34. [The impact of augmented reality glasses on human visual efficiency and digital eye fatigue].
- Author
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Xu ZH, Wu JF, Lei JY, and Jin ZB
- Subjects
- Male, Female, Humans, Young Adult, Adult, Prospective Studies, Visual Acuity, Vision, Ocular, Asthenopia, Augmented Reality
- Abstract
Objective: To investigate the differences in reading efficiency and visual fatigue between the use of augmented reality (AR) glasses and laptops. Methods: A prospective self-controlled study was conducted. Healthy students from Capital Medical University who frequently engaged in long-term near work and used laptops and other digital display devices were recruited as subjects at Beijing Tongren Hospital, Capital Medical University between November 1 and November 15, 2023. LogMAR visual acuity, visual functions (accommodation, convergence, and fusion), and visual fatigue scores (Likert visual fatigue scale) of the participants were assessed. The order of using the laptop and AR glasses for each participant was determined by a coin toss. Reading efficiency (reading speed and error rate multiplied by the detection rate of incorrect numbers) with different devices for 10 minutes at the same time on different dates and visual fatigue scores after watching a 20-minute video were measured. Statistical analyses were performed using paired t-tests and Wilcoxon signed-rank tests. Results: A total of 20 eligible subjects were included, comprising 7 males and 13 females, with a mean age of (25.45±2.27) years. There was no significant change in binocular visual acuity before and after using AR glasses and laptops (both P >0.05). The reading speed and reading efficiency of using AR glasses [(34.03±9.25) and (29.19±7.62) digits/min, respectively] were significantly lower than those of using laptops [(39.43±10.36) and (35.67±9.87) digits/min, respectively] ( t =4.36, P <0.001), while the difference in error detection rate was not statistically significant ( t =1.29, P =0.213). There was no statistically significant difference in visual fatigue scores before watching videos with the two devices ( Z =-0.71, P =0.480). However, the visual fatigue score after watching videos with AR glasses [(20.55±5.04) points] was significantly higher than that with laptops [16.50 (13.00, 19.75) points] ( Z =-2.85, P =0.004). The visual fatigue scores after watching videos with both devices were significantly higher than before ( P <0.05), with a more significant increase observed with AR glasses [(6.05±3.50) points] ( Z =-3.41, P <0.001). Conclusion: Compared with using laptops, the reading speed and efficiency were lower, and the visual fatigue was more pronounced with the use of AR glasses at the current technical level. Further optimization and improvement of AR glasses are warranted.
- Published
- 2024
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35. Gaze-contingent processing improves mobility, scene recognition and visual search in simulated head-steered prosthetic vision.
- Author
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de Ruyter van Steveninck J, Nipshagen M, van Gerven M, Güçlü U, Güçlüturk Y, and van Wezel R
- Subjects
- Humans, Prospective Studies, Eye Movements, Computer Simulation, Activities of Daily Living, Vision, Ocular
- Abstract
Objective. The enabling technology of visual prosthetics for the blind is making rapid progress. However, there are still uncertainties regarding the functional outcomes, which can depend on many design choices in the development. In visual prostheses with a head-mounted camera, a particularly challenging question is how to deal with the gaze-locked visual percept associated with spatial updating conflicts in the brain. The current study investigates a recently proposed compensation strategy based on gaze-contingent image processing with eye-tracking. Gaze-contingent processing is expected to reinforce natural-like visual scanning and reestablished spatial updating based on eye movements. The beneficial effects remain to be investigated for daily life activities in complex visual environments. Approach. The current study evaluates the benefits of gaze-contingent processing versus gaze-locked and gaze-ignored simulations in the context of mobility, scene recognition and visual search, using a virtual reality simulated prosthetic vision paradigm with sighted subjects. Main results. Compared to gaze-locked vision, gaze-contingent processing was consistently found to improve the speed in all experimental tasks, as well as the subjective quality of vision. Similar or further improvements were found in a control condition that ignores gaze-dependent effects, a simulation that is unattainable in the clinical reality. Significance. Our results suggest that gaze-locked vision and spatial updating conflicts can be debilitating for complex visually-guided activities of daily living such as mobility and orientation. Therefore, for prospective users of head-steered prostheses with an unimpaired oculomotor system, the inclusion of a compensatory eye-tracking system is strongly endorsed., (Creative Commons Attribution license.)
- Published
- 2024
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36. A bionic self-driven retinomorphic eye with ionogel photosynaptic retina.
- Author
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Luo X, Chen C, He Z, Wang M, Pan K, Dong X, Li Z, Liu B, Zhang Z, Wu Y, Ban C, Chen R, Zhang D, Wang K, Wang Q, Li J, Lu G, Liu J, Liu Z, and Huang W
- Subjects
- Bionics, Retina, Vision, Ocular, Visual Perception, Visual Prosthesis
- Abstract
Bioinspired bionic eyes should be self-driving, repairable and conformal to arbitrary geometries. Such eye would enable wide-field detection and efficient visual signal processing without requiring external energy, along with retinal transplantation by replacing dysfunctional photoreceptors with healthy ones for vision restoration. A variety of artificial eyes have been constructed with hemispherical silicon, perovskite and heterostructure photoreceptors, but creating zero-powered retinomorphic system with transplantable conformal features remains elusive. By combining neuromorphic principle with retinal and ionoelastomer engineering, we demonstrate a self-driven hemispherical retinomorphic eye with elastomeric retina made of ionogel heterojunction as photoreceptors. The receptor driven by photothermoelectric effect shows photoperception with broadband light detection (365 to 970 nm), wide field-of-view (180°) and photosynaptic (paired-pulse facilitation index, 153%) behaviors for biosimilar visual learning. The retinal photoreceptors are transplantable and conformal to any complex surface, enabling visual restoration for dynamic optical imaging and motion tracking., (© 2024. The Author(s).)
- Published
- 2024
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37. Eye blinks as a visual processing stage.
- Author
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Yang B, Intoy J, and Rucci M
- Subjects
- Humans, Photic Stimulation, Visual Perception physiology, Vision, Ocular, Blinking, Eye Movements
- Abstract
Humans blink their eyes frequently during normal viewing, more often than it seems necessary for keeping the cornea well lubricated. Since the closure of the eyelid disrupts the image on the retina, eye blinks are commonly assumed to be detrimental to visual processing. However, blinks also provide luminance transients rich in spatial information to neural pathways highly sensitive to temporal changes. Here, we report that the luminance modulations from blinks enhance visual sensitivity. By coupling high-resolution eye tracking in human observers with modeling of blink transients and spectral analysis of visual input signals, we show that blinking increases the power of retinal stimulation and that this effect significantly enhances visibility despite the time lost in exposure to the external scene. We further show that, as predicted from the spectral content of input signals, this enhancement is selective for stimuli at low spatial frequencies and occurs irrespective of whether the luminance transients are actively generated or passively experienced. These findings indicate that, like eye movements, blinking acts as a computational component of a visual processing strategy that uses motor behavior to reformat spatial information into the temporal domain., Competing Interests: Competing interests statement:The authors declare no competing interest.
- Published
- 2024
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38. High-resolution vision in pelagic polychaetes.
- Author
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Bok MJ, Macali A, and Garm A
- Subjects
- Animals, Eye anatomy & histology, Mollusca, Ecology, Vision, Ocular, Arthropods
- Abstract
High-resolution object vision - the ability to separate, classify, and interact with specific objects in the environment against the visual background - has only been conclusively shown to have evolved in three of the thirty-five animal phyla: chordates, arthropods, and mollusks (cephalopods)
1 . However, alciopid polychaetes (Phyllodocidae, Alciopini), which possess a pair of bulbous camera-type eyes, have also been hypothesized to achieve high acuity. In this study, we examined three species of night-active pelagic alciopids from the Mediterranean Sea. Our optical, morphological, and electrophysiological investigations show that their eyes have high spatial acuity and temporal resolution, supporting the notion that they are capable of active, high-resolution object vision. These results encourage interesting hypotheses about the visual ecology of these enigmatic polychaetes., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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39. Osmosis as nature's method for establishing optical alignment.
- Author
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Rathore S, Mitra AT, Hyland-Brown R, Jester A, Layne JE, Benoit JB, and Buschbeck EK
- Subjects
- Animals, Larva physiology, Retina, Osmosis, Vision, Ocular, Coleoptera physiology
- Abstract
For eyes to maintain optimal focus, precise coordination is required between lens optics and retina position, a mechanism that in vertebrates is governed by genetics, visual feedback, and possibly intraocular pressure (IOP).
1 While the underlying processes have been intensely studied in vertebrates, they remain elusive in arthropods, though visual feedback may be unimportant.2 How do arthropod eyes remain functional while undergoing substantial growth? Here, we test whether a common physiological process, osmoregulation,3 could regulate growth in the sophisticated camera-type eyes of the predatory larvae of Thermonectus marmoratus diving beetles. Upon molting, their eye tubes elongate in less than an hour, and osmotic pressure measurements reveal that this growth is preceded by a transient increase in hemolymph osmotic pressure. Histological evaluation of support cells that determine the lens-to-retina spacing reveals swelling rather than the addition of new cells. In addition, as expected, treating larvae with hyperosmotic media post-molt leads to far-sighted (hyperopic) eyes due to a failure of proper lengthening of the eye tube and results in impaired hunting success. This study suggests that osmoregulation could be of ubiquitous importance for properly focused eyes., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
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40. Autokinesis Reveals a Threshold for Perception of Visual Motion.
- Author
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Liu Y, Tian J, Martin-Gomez A, Arshad Q, Armand M, and Kheradmand A
- Subjects
- Humans, Visual Perception, Vision, Ocular, Psychomotor Performance, Retina, Motion Perception
- Abstract
In natural viewing conditions, the brain can optimally integrate retinal and extraretinal signals to maintain a stable visual perception. These mechanisms, however, may fail in circumstances where extraction of a motion signal is less viable such as impoverished visual scenes. This can result in a phenomenon known as autokinesis in which one may experience apparent motion of a small visual stimulus in an otherwise completely dark environment. In this study, we examined the effect of autokinesis on visual perception of motion in human observers. We used a novel method with optical tracking in which the visual motion was reported manually by the observer. Experiment results show at lower speeds of motion, the perceived direction of motion was more aligned with the effect of autokinesis, whereas in the light or at higher speeds in the dark, it was more aligned with the actual direction of motion. These findings have important implications for understanding how the stability of visual representation in the brain can affect accurate perception of motion signals., (Copyright © 2024 IBRO. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
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41. The effect on income of providing near vision correction to workers in Bangladesh: The THRIVE (Tradespeople and Hand-workers Rural Initiative for a Vision-enhanced Economy) randomized controlled trial.
- Author
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Sehrin F, Jin L, Naher K, Das NC, Chan VF, Li DF, Bergson S, Gudwin E, Clarke M, Stephan T, and Congdon N
- Subjects
- Female, Humans, Male, Middle Aged, Bangladesh, Quality of Life, Vision, Ocular, Adult, Aged, Myopia, Presbyopia
- Abstract
Introduction: Presbyopia, the leading cause of vision impairment globally, is common during working years. However, no trials have assessed presbyopia's impact on income., Methods: In April 2017, we conducted a census among 59 Bangladesh villages to identify persons aged 35 to 65 years with presbyopia (presenting distance vision > = 6/12 bilaterally and correctable inability to see 6/13 at 40 cm with both eyes), who never had owned glasses. Participants were randomized (1:1) to receive immediate free reading glasses (intervention) or glasses delivered 8 months later (control). Visual demand of different jobs was stratified into three levels. Outcomes were between-group differences in the 8 month change in: self-reported monthly income (primary) and Near Vision Related Quality of Life (NVRQOL, secondary)., Results: Among 10,884 census participants, 3,655 (33.6%) met vision criteria and 863 (23.6%) comprised a sample enriched for near vision-intensive jobs, but 39 (4.52%) could not be reached. All participants allocated to intervention (n = 423, 51.3%) and control (n = 401, 48.7%) received the appropriate intervention, and follow-up was available for 93.4% and 96.8% respectively. Groups were similar at baseline in all characteristics: mean age was 47 years, 50% were male, 35% literate, and about half engaged in "most near vision-intensive" occupations. Glasses wear at 8-month follow-up was 88.3% and 7.81% in intervention and control respectively. At baseline, both the intervention and control groups had a self-reported median monthly income of US$35.3. At endline, the median income for the intervention group was US$47.1 compared with US$35.3 for control, a difference of 33.4%. Predictors of greater income increase in multivariate models included intervention group allocation (OR 1.45, 95% CI 1.12, 1.88, P = 0.005), male sex (OR 2.41, 95% CI 1.84, 3.16, P <0.001), and not engaging in income-producing work at baseline (OR 2.35, 95% CI 1.69, 3.26, P<0.001)., Conclusion: Provision of reading glasses increases income in near vision-intensive occupations, and may facilitate return to work for those currently unemployed., Competing Interests: Sehrin, Jin, Naher, Chandra Das, Chan and Clarke declare no competing interests. Gudwin and Bergson report personal fees from VisionSpring, a social enterprise engaged in the distribution and sale of eyewear, outside the submitted work. Congdon is Director of Research for Orbis International, a non-governmental organization carrying out eye health programs in low and middle-income countries, outside the submitted work. Congdon also received salary support from Ulverscroft Foundation, a UK-registered charity, at the time of this work. Stephan is a Global Programs Manager for Orbis International outside the submitted work. None of these interests alters our adherence to PLOS ONE policies on sharing data and materials., (Copyright: © 2024 Sehrin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2024
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42. Scotopic and Photopic Conventional Visual Acuity and Hyperacuity - Binocular Summation.
- Author
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Korn S, Al-Nosairy KO, Gopiswaminathan AV, João C, Scanferla L, Bach M, and Hoffmann MB
- Subjects
- Young Adult, Humans, Female, Adult, Visual Acuity, Vision, Ocular, Biomarkers, Vision Tests methods, Vision, Binocular
- Abstract
Purpose: The purpose of this study was to determine and compare binocular summation (BiS) of conventional visual acuity (cVA) versus hyperacuity (hVA) for photopic and scotopic luminance conditions as a potential biomarker to assess the outcome of interventions on binocular function., Methods: Sixteen young adults (age range [years] = 21-31; 8 women; cVA logMAR < 0.0) participated in this study. The Freiburg Visual Acuity Test (FrACT) was used for VA testing and retested on another day. Both cVA and hVA were determined for dark grey optotypes on light grey background. Participants underwent 40 minutes of dark adaptation prior to scotopic VA testing. Binocular and monocular VA testing was performed. The eye with better VA over the 2 days of testing was selected, the BiS was quantified (binocular VA - better monocular VA) and repeated measures ANOVAs were performed., Results: Binocular VA exceeded monocular VA for all luminance conditions, VA-types, and sessions. We report BiS estimates for photopic and scotopic cVA and hVA, (logMAR BiS ± SEM [decimal BiS]): photopic = -0.01 ± 0.01 [1.03] and -0.06 ± 0.03 [1.15]; and scotopic = -0.05 ± 0.01 [1.12] and -0.11 ± 0.04 [1.28], respectively). Improvement for binocular vision estimates ranged from 0.01 to 0.11 logMAR. A repeated-measures ANOVA (RM ANOVA) did not reveal significant effects of LUMINANCE or VA TYPE on BiS, albeit a trend for strongest BiS for scotopic hVA (15% vs. 28%, photopic versus scotopic, respectively) and weakest for photopic cVA (3% vs. 12%, photopic versus scotopic conditions, respectively)., Conclusions: Our results indicate that BiS of VA is relevant to scotopic and photopic hVA and cVA. It appears therefore a plausible candidate biomarker to assess the outcome of retinal therapies restoring rod or cone function on binocular vision., Translational Relevance: Binocular summation of visual acuity might serve as a clinical biomarker to monitor therapy outcome on binocular rod and cone-mediated vision.
- Published
- 2024
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43. Carl Bergmann (1814-1865) and the discovery of the anatomical site in the retina where vision is initiated.
- Author
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Thibos L, Lenner K, and Thibos C
- Subjects
- Male, Humans, Retinal Cone Photoreceptor Cells physiology, Retinal Rod Photoreceptor Cells physiology, Brain, Retina physiology, Vision, Ocular
- Abstract
A preeminent quest of nineteenth-century visual neuroscience was to identify the anatomical elements of the retina that respond to light. A major breakthrough came in 1854, when Carl Bergmann discovered through direct observation that the human fovea contains only rods and cones. On this basis, he argued that these must necessarily be the light-sensitive elements (i.e., photoreceptors) that initiate vision. Bergmann also argued that Henle's fibers form part of the necessary anatomical link between these distal elements and the proximal ganglion cells, which transmit visual signals to the brain via the optic nerve. However, despite his achievement, Heinrich Müller, not Bergmann, is remembered as the discoverer of human photoreceptors in the literature. This article seeks to correct the record. It situates Bergmann's work alongside that of his contemporaries, sets out his arguments and the critique he received using archival documents, and makes this history more accessible for current readers by comparing what was said to what we know now. We argue that Bergmann's arguments are at least as compelling as those of Müller, and that he should be recognized as a codiscoverer of the anatomic site in the retina where vision is initiated.
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- 2024
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44. ISCEV standard for clinical pattern electroretinography (2024 update).
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Thompson DA, Bach M, McAnany JJ, Šuštar Habjan M, Viswanathan S, and Robson AG
- Subjects
- Retina, Vision, Ocular, Retinal Ganglion Cells, Electroretinography methods, Evoked Potentials, Visual
- Abstract
The pattern electroretinogram (PERG) is a localized retinal response evoked by a contrast-reversing pattern, usually a black and white checkerboard, which provides information about macular and retinal ganglion cell function. This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV; www.iscev.org ) presents an updated and revised Standard for clinical PERG testing. This replaces the 2013 and all earlier versions. Minimum protocols for basic PERG stimuli, recording methods and reporting are specified, to promote consistency of methods for diagnosis and monitoring purposes, while responding to evolving clinical practices and technology. The main changes in the updated ISCEV Standard for clinical PERG include expanded guidance about large stimulus fields, stimulus parameters for simultaneous PERG and pattern visual evoked potential recording, baseline drift correction, and use of consistent ambient room lighting. These changes aim to provide a clinically relevant document about current practice which will facilitate good quality recordings and inter-laboratory comparisons., (© 2024. The Author(s).)
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- 2024
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45. The nature and distribution of putative non-functional alleles suggest only two independent events at the origins of Astyanax mexicanus cavefish populations.
- Author
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Policarpo M, Legendre L, Germon I, Lafargeas P, Espinasa L, Rétaux S, and Casane D
- Subjects
- Animals, Alleles, Mutation, Blindness genetics, Vision, Ocular, Characidae genetics
- Abstract
Background: Several studies suggested that cavefish populations of Astyanax mexicanus settled during the Late Pleistocene. This implies that the cavefish's most conspicuous phenotypic changes, blindness and depigmentation, and more cryptic characters important for cave life, evolved rapidly., Results: Using the published genomes of 47 Astyanax cavefish from la Cueva de El Pachón, El Sótano de la Tinaja, La Cueva Chica and El Sótano de Molino, we searched for putative loss-of-function mutations in previously defined sets of genes, i.e., vision, circadian clock and pigmentation genes. Putative non-functional alleles for four vision genes were identified. Then, we searched genome-wide for putative non-functional alleles in these four cave populations. Among 512 genes with segregating putative non-functional alleles in cavefish that are absent in surface fish, we found an enrichment in visual perception genes. Among cavefish populations, different levels of shared putative non-functional alleles were found. Using a subset of 12 genes for which putative loss-of-function mutations were found, we extend the analysis of shared pseudogenes to 11 cave populations. Using a subset of six genes for which putative loss-of-function mutations were found in the El Sótano del Toro population, where extensive hybridization with surface fish occurs, we found a correlation between the level of eye regression and the amount of putative non-functional alleles., Conclusions: We confirm that very few putative non-functional alleles are present in a large set of vision genes, in accordance with the recent origin of Astyanax mexicanus cavefish. Furthermore, the genome-wide analysis indicates an enrichment of putative loss-of-function alleles in genes with vision-related GO-terms, suggesting that visual perception may be the function chiefly impacted by gene losses related to the shift from a surface to a cave environment. The geographic distribution of putative loss-of-function alleles newly suggests that cave populations from Sierra de Guatemala and Sierra de El Abra share a common origin, albeit followed by independent evolution for a long period. It also supports that populations from the Micos area have an independent origin. In El Sótano del Toro, the troglomorphic phenotype is maintained despite massive introgression of the surface genome., (© 2024. The Author(s).)
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- 2024
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46. Tau-Cell-Based Analog Silicon Retina With Spatio- Temporal Filtering and Contrast Gain Control.
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Philip P, Jainwal K, van Schaik A, and Thakur CS
- Subjects
- Vision, Ocular, Artificial Intelligence, Computer Simulation, Silicon, Retina
- Abstract
Developing precise artificial retinas is crucial because they hold the potential to restore vision, improve visual prosthetics, and enhance computer vision systems. Emulating the luminance and contrast adaption features of the retina is essential to improve visual perception and efficiency to provide an environment realistic representation to the user. In this article, we introduce an artificial retina model that leverages its potent adaptation to luminance and contrast to enhance vision sensing and information processing. The model has the ability to achieve the realization of both tonic and phasic cells in the simplest manner. We have implemented the retina model using 0.18 μm process technology and validated the accuracy of the hardware implementation through circuit simulation that closely matches the software retina model. Additionally, we have characterized a single pixel fabricated using the same 0.18 μm process. This pixel demonstrates an 87.7-% ratio of variance with the temporal software model and operates with a power consumption of 369 nW.
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- 2024
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47. Detection of retinal dysfunction induced by HCN channel inhibitors using multistep light stimulus and long-duration light stimulus ERG in rats.
- Author
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Umeya N, Yoshizawa Y, Fukuda K, Ikeda K, Kamada M, Inada H, Usui T, and Miyawaki I
- Subjects
- Mice, Humans, Rats, Animals, Ivabradine, Retina, Vision, Ocular, Vision Disorders, Mice, Knockout, Photic Stimulation, Electroretinography, Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels
- Abstract
Ivabradine, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel inhibitor, has been reported to induce photosensitivity-related visual disturbances such as phosphene in humans. Ivabradine-induced visual disturbances are caused by inhibition of HCN channels in the retina, and the mechanisms have been verified using HCN channel knockout mice and electroretinography (ERG). However, in rats, classical ERG using single flash light stimulus with standard analyses of waveform amplitude and latency has not revealed abnormal retinal function after administration of ivabradine. To verify whether retinal dysfunction after ivabradine administration was detectable in rats, we performed ERG using multistep flash light stimulation at the time when plasma concentration of ivabradine was high. Furthermore, the mechanism of the change in the waveform that appeared after the b-wave was investigated. Ivabradine and cilobradine, a selective HCN channel inhibitor, were administered subcutaneously to rats at 4-40 mg/kg as a single dose, and flash or long-duration ERG recordings at each light stimulus luminance were conducted 1.5 h after administration. Plasma and retinal concentrations of both compounds were measured immediately after the ERG recordings. In the flash ERG, prolongation of a- and/or b-wave latencies were detected at each light stimulus, and dose-dependent waveform changes after the b-wave were recorded at the specific light stimulus luminance for both compounds. These ERG changes increased in response to increasing plasma and retinal concentrations for both ivabradine and cilobradine. In the long-duration light stimulus ERG, a change in the waveform of the b-wave trough and attenuation of the c-wave were recorded, suggesting that the feedback control in the photoreceptor cells may be inhibited. This study revealed that the retinal dysfunction by HCN channel inhibitors in rats can be detected by multistep light stimulus ERG. Additionally, we identified that the inhibition of feedback current and the sustained responses in the photoreceptor cells cause the retinal dysfunction of HCN channel inhibitors in rats., Competing Interests: Declaration of competing interest Naohisa Umeya, Yuki Yoshizawa, Kosuke Fukuda, Keigo Ikeda, Mami Kamada, Hiroshi Inada, Toru Usui and Izuru Miyawaki are employees of Sumitomo Pharma Co., Ltd., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
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- 2024
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48. Ocular oxidative changes and antioxidant therapy during spaceflight.
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Masalkhi M, Ong J, Waisberg E, and Lee AG
- Subjects
- Humans, Eye, Vision, Ocular, Oxidative Stress, Antioxidants therapeutic use, Space Flight
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- 2024
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49. Characterization of lncRNA and mRNA profiles in ciliary body in experimental myopia.
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Wu S, Hao J, Guo D, Ma Z, Wu Q, Zhang M, and Bi H
- Subjects
- Animals, Guinea Pigs, Ciliary Body metabolism, RNA, Messenger genetics, RNA, Messenger metabolism, Vision, Ocular, RNA, Long Noncoding genetics, Myopia
- Abstract
Currently, researchers have mainly focused on the role of the tissues of the posterior segment of the eyes in the development of myopia. However, the ciliary body, an anterior ocular tissue that contracts to initiate the process of accommodation, may also play an important role in the progression of myopia due to the increased demand for near work. In the present study, we established a lens-induced myopia (LIM) animal model in guinea pigs and investigated the molecular changes in the ciliary body associated with the development of myopia based on RNA sequencing. As a result, 871 differentially expressed (DE) mRNAs and 19 DE lncRNAs were identified in the ciliary body between the LIM group and the normal control group. In addition, the lncRNA-mRNA co-expression analysis was performed to explore the target genes of lncRNAs, which were mainly enriched in the Rap1 signaling pathway, cytokine-cytokine receptor interaction, and complement and coagulation cascades pathways based on the functional enrichment analysis. Among the target genes of lncRNAs, three hub genes, including Ctnnb1, Pik3r1, and Itgb1, were found to be involved in the Rap1 signaling pathway. Interestingly, two crucial genes, Grk1 and Pde6a, which are mainly expressed in retinal photoreceptors, were enriched in visual perception in the ciliary body in functional analysis and were verified to be expressed in the ciliary body. These findings indicate the molecular pathogenetic role of the ciliary body in myopia and provide new insights into the underlying mechanism of myopia development. Further studies are needed to explore the specific contributions of these identified lncRNAs and mRNAs to the development of myopia., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
50. Turbidity drives plasticity in the eyes and brains of an African cichlid.
- Author
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Tiarks JH, Gray SM, and Chapman LJ
- Subjects
- Animals, Eye, Brain anatomy & histology, Fresh Water chemistry, Vision, Ocular, Cichlids physiology
- Abstract
Natural variation in environmental turbidity correlates with variation in the visual sensory system of many fishes, suggesting that turbidity may act as a strong selective agent on visual systems. Since many aquatic systems experience increased turbidity due to anthropogenic perturbations, it is important to understand the degree to which fish can respond to rapid shifts in their visual environment, and whether such responses can occur within the lifetime of an individual. We examined whether developmental exposure to turbidity (clear, <5 NTU; turbid, ∼9 NTU) influenced the size of morphological structures associated with vision in the African blue-lip cichlid Pseudocrenilabrus multicolor. Parental fish were collected from two sites (clear swamp, turbid river) in western Uganda. F1 broods from each population were split and reared under clear and turbid rearing treatments until maturity. We measured morphological traits associated with the visual sensory system (eye diameter, pupil diameter, axial length, brain mass, optic tectum volume) over the course of development. Age was significant in explaining variation in visual traits even when standardized for body size, suggesting an ontogenetic shift in the relative size of eyes and brains. When age groups were analyzed separately, young fish reared in turbid water grew larger eyes than fish reared in clear conditions. Population was important in the older age category, with swamp-origin fish having relatively larger eyes and optic lobes relative to river-origin fish. Plastic responses during development may be important for coping with a more variable visual environment associated with anthropogenically induced turbidity., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
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