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1.
Sci Adv ; 10(9): eadi9294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38427730

RESUMO

Previous research shows that the beauty of natural images is already determined during perceptual analysis. However, it is unclear which perceptual computations give rise to the perception of beauty. Here, we tested whether perceived beauty is predicted by spatial integration across an image, a perceptual computation that reduces processing demands by aggregating image parts into more efficient representations of the whole. We quantified integrative processing in an artificial deep neural network model, where the degree of integration was determined by the amount of deviation between activations for the whole image and its constituent parts. This quantification of integration predicted beauty ratings for natural images across four studies with different stimuli and designs. In a complementary functional magnetic resonance imaging study, we show that integrative processing in human visual cortex similarly predicts perceived beauty. Together, our results establish integration as a computational principle that facilitates perceptual analysis and thereby mediates the perception of beauty.


Assuntos
Córtex Visual , Percepção Visual , Humanos , Visão Ocular , Córtex Visual/diagnóstico por imagem , Imageamento por Ressonância Magnética , Julgamento , Mapeamento Encefálico
2.
Curr Biol ; 34(5): R195-R197, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38471446

RESUMO

The representation of visual shape is a critical component of our perception of the objects around us. A new study exploited shape aftereffects to reveal the high-dimensional space of geometric features our brains use to represent shape.


Assuntos
Percepção de Forma , Percepção Visual , Estimulação Luminosa/métodos , Visão Ocular , Reconhecimento Visual de Modelos
3.
Sci Rep ; 14(1): 6097, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480839

RESUMO

We recently showed that the gain of the pupillary light response depends on numerosity, with weaker responses to fewer items. Here we show that this effect holds when the stimuli are physically identical but are perceived as less numerous due to numerosity adaptation. Twenty-eight participants adapted to low (10 dots) or high (160 dots) numerosities and subsequently watched arrays of 10-40 dots, with variable or homogeneous dot size. Luminance was constant across all stimuli. Pupil size was measured with passive viewing, and the effects of adaptation were checked in a separate psychophysical session. We found that perceived numerosity was systematically lower, and pupillary light responses correspondingly smaller, following adaptation to high rather than low numerosities. This is consistent with numerosity being a primary visual feature, spontaneously encoded even when task irrelevant, and affecting automatic and unconscious behaviours like the pupillary light response.


Assuntos
Pupila , Visão Ocular , Humanos , Conceitos Matemáticos , Inconsciência , Luz
4.
Commun Biol ; 7(1): 317, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480875

RESUMO

Primate communication relies on multimodal cues, such as vision and audition, to facilitate the exchange of intentions, enable social interactions, avoid predators, and foster group cohesion during daily activities. Understanding the integration of facial and vocal signals is pivotal to comprehend social interaction. In this study, we acquire whole-brain ultra-high field (9.4 T) fMRI data from awake marmosets (Callithrix jacchus) to explore brain responses to unimodal and combined facial and vocal stimuli. Our findings reveal that the multisensory condition not only intensifies activations in the occipito-temporal face patches and auditory voice patches but also engages a more extensive network that includes additional parietal, prefrontal and cingulate areas, compared to the summed responses of the unimodal conditions. By uncovering the neural network underlying multisensory audiovisual integration in marmosets, this study highlights the efficiency and adaptability of the marmoset brain in processing facial and vocal social signals, providing significant insights into primate social communication.


Assuntos
Callithrix , Imageamento por Ressonância Magnética , Animais , Callithrix/fisiologia , Visão Ocular , Mapeamento Encefálico , Percepção Auditiva/fisiologia
5.
Brain Behav ; 14(3): e3462, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38468484

RESUMO

INTRODUCTION: The objective of this study was to investigate changes in vision-related resting-state activity in patients with suprasellar tumors (ST) who experienced vision deterioration after surgery. METHODS: Twelve patients with ST and vision deterioration after surgery were included in the study. Resting-state functional connectivity (FC) was compared before and after surgery using a seed-based analysis with a priori specified regions of interest (ROIs) within the visual areas. The differences between the two groups were identified using a paired t-test. RESULTS: The data showed a decrease in FC within and between the dorsal and ventral pathways, as well as in the third pathway in ST patients. The middle temporal visual cortex (MT+) showed a decreased FC with more regions than other visual ROIs. The data also revealed an increase in FC between the visual ROIs and higher-order cortex. The superior frontal gyrus/BA8 showed an increased FC with more ROIs than other high-order regions, and the hOC4d was involved in an increased FC with more high-order regions than other ROIs. CONCLUSIONS: The study results indicate significant neural reorganization in the vision-related cortex of ST patients with postoperative vision damage. Most subareas within the visual cortex showed remarkable neural dysfunction, and some highe-order cortex may be primarily involved in top-down control of the subareas within the visual cortex. The hot zones may arise in the processing of "top-down" influence.


Assuntos
Neoplasias , Córtex Visual , Humanos , Imageamento por Ressonância Magnética/métodos , Visão Ocular , Córtex Visual/diagnóstico por imagem , Lobo Temporal , Encéfalo
6.
PLoS One ; 19(3): e0299129, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427630

RESUMO

OBJECTIVE: It is currently still unknown why some drivers with visual field loss can compensate well for their visual impairment while others adopt ineffective strategies. This paper contributes to the methodological investigation of the associated top-down mechanisms and aims at validating a theoretical model on the requirements for successful compensation among drivers with homonymous visual field loss. METHODS: A driving simulator study was conducted with eight participants with homonymous visual field loss and eight participants with normal vision. Participants drove through an urban surrounding and experienced a baseline scenario and scenarios with visual precursors indicating increased likelihoods of crossing hazards. Novel measures for the assessment of the mental model of their visual abilities, the mental model of the driving scene and the perceived attention demand were developed and used to investigate the top-down mechanisms behind attention allocation and hazard avoidance. RESULTS: Participants with an overestimation of their visual field size tended to prioritize their seeing side over their blind side both in subjective and objective measures. The mental model of the driving scene showed close relations to the subjective and actual attention allocation. While participants with homonymous visual field loss were less anticipatory in their usage of the visual precursors and showed poorer performances compared to participants with normal vision, the results indicate a stronger reliance on top-down mechanism for drivers with visual impairments. A subjective focus on the seeing side or on near peripheries more frequently led to bad performances in terms of collisions with crossing cyclists. CONCLUSION: The study yielded promising indicators for the potential of novel measures to elucidate top-down mechanisms in drivers with homonymous visual field loss. Furthermore, the results largely support the model of requirements for successful compensatory scanning. The findings highlight the importance of individualized interventions and driver assistance systems tailored to address these mechanisms.


Assuntos
Condução de Veículo , Campos Visuais , Humanos , Transtornos da Visão , Visão Ocular , Testes de Campo Visual , Acidentes de Trânsito
7.
Transl Vis Sci Technol ; 13(3): 13, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497518

RESUMO

Purpose: To evaluate whether latent class analysis on social determinants of health (SDoH) data can identify social risk groups that differ by adverse SDoH and vision outcomes in patients with diabetes. Methods: This was a prospective cohort study of adults ≥18 years with diabetes who completed a SDoH survey. Latent class analysis was used to cluster patients into social risk groups. The association of social risk group and severity of diabetic retinopathy, history of lapses in diabetic retinopathy care, and visual acuity was evaluated. Results: A total of 1006 participants were included. The three social risk groups differed by sociodemographic characteristics. The average age was 65, 60, and 54 in Groups 1, 2, and 3 respectively. Most (51%) patients in group 1 were non-Hispanic White, 66% in group 2 were non-Hispanic Black, and 80% in group 3 were Hispanic. Group 1 had the lowest burden of adverse SDoH per person (average 3.6), group 2 had 8.2, and group 3 had 10.5. In general, group 1 lacked diabetic retinopathy knowledge, group 2 had financial insecurity and difficulties with transportation, and group 3 had financial insecurity and did not have health insurance. Social risk group was associated with a history of lapses in diabetic retinopathy care, and presenting with worse vision. Conclusions and Translational Relevance: We identified distinct social risk groups among patients seeking care for diabetic retinopathy that differed by social needs, eye care utilization, and vision. Identifying these groups and their specific needs can help guide interventions to effectively address adverse SDoH and improve eye care utilization and vision outcomes among patients with diabetes.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Adulto , Humanos , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/terapia , Estudos Prospectivos , Visão Ocular , Acuidade Visual , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia
8.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521995

RESUMO

In brightness, the pupil constricts, while in darkness, the pupil dilates; this is known as the pupillary light response (PLR). The PLR is driven by all photoreceptors: rods and cones, which contribute to image-forming vision, and intrinsically photosensitive retinal ganglion cells (ipRGCs), which mainly contribute to non-image-forming vision. Rods and cones cause immediate pupil constriction upon light exposure, whereas ipRGCs cause sustained constriction throughout light exposure. Recent studies have shown that covert attention modulated the initial PLR; however, it remains unclear whether the same holds for the sustained PLR. We tested this by leveraging ipRGCs' responsiveness to blue light, causing the most prominent sustained constriction. While replicating previous studies by showing that pupils constricted more when either directly looking at, or covertly attending to, bright as compared to dim stimuli (with the same color), we also found that the pupil constricted more when directly looking at blue as compared to red stimuli (with the same luminosity). Crucially, however, in two high-powered studies (n = 60), we did not find any pupil-size difference when covertly attending to blue as compared to red stimuli. This suggests that ipRGC-mediated pupil constriction, and possibly non-image-forming vision more generally, is not modulated by covert attention.


Assuntos
Células Ganglionares da Retina , Visão Ocular , Constrição , Células Ganglionares da Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Luz , Estimulação Luminosa
9.
Doc Ophthalmol ; 148(2): 75-85, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488946

RESUMO

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.


Assuntos
Eletrorretinografia , Potenciais Evocados Visuais , Eletrorretinografia/métodos , Retina , Visão Ocular , Células Ganglionares da Retina
10.
Neuroscience ; 543: 101-107, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38432549

RESUMO

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.


Assuntos
Percepção de Movimento , Humanos , Percepção Visual , Visão Ocular , Desempenho Psicomotor , Retina
11.
BMC Biol ; 22(1): 28, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317216

RESUMO

BACKGROUND: The human brain can rapidly represent sets of similar stimuli by their ensemble summary statistics, like the average orientation or size. Classic models assume that ensemble statistics are computed by integrating all elements with equal weight. Challenging this view, here, we show that ensemble statistics are estimated by combining parafoveal and foveal statistics in proportion to their reliability. In a series of experiments, observers reproduced the average orientation of an ensemble of stimuli under varying levels of visual uncertainty. RESULTS: Ensemble statistics were affected by multiple spatial biases, in particular, a strong and persistent bias towards the center of the visual field. This bias, evident in the majority of subjects and in all experiments, scaled with uncertainty: the higher the uncertainty in the ensemble statistics, the larger the bias towards the element shown at the fovea. CONCLUSION: Our findings indicate that ensemble perception cannot be explained by simple uniform pooling. The visual system weights information anisotropically from both the parafovea and the fovea, taking the intrinsic spatial anisotropies of vision into account to compensate for visual uncertainty.


Assuntos
Encéfalo , Visão Ocular , Humanos , Anisotropia , Reprodutibilidade dos Testes , Percepção
13.
J Exp Child Psychol ; 241: 105856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38306737

RESUMO

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.


Assuntos
Tecnologia Háptica , Visão Ocular , Criança , Humanos , Tato , Som , Emoções
14.
J Exp Child Psychol ; 241: 105870, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38354447

RESUMO

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.


Assuntos
Percepção do Tato , Percepção Visual , Adulto , Criança , Humanos , Adolescente , Tecnologia Háptica , Visão Ocular , Aprendizagem Espacial , Conhecimento
15.
Cesk Slov Oftalmol ; 80(Ahead of print): 1-6, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38413228

RESUMO

PURPOSE: The purpose of the article is to present the history and current status of visual cortical neuroprostheses, and to present a new method of stimulating intact visual cortex cells. METHODS: This paper contains an overview of the history and current status of visual cortex stimulation in severe visual impairment, but also highlights its shortcomings. These include mainly the stimulation of currently damaged cortical cells over a small area and, from a morphological point of view, possible damage to the stimulated neurons by the electrodes and their encapsulation by gliotic tissue. RESULTS: The paper also presents a proposal for a new technology of image processing and its transformation into a form of non-invasive transcranial stimulation of undamaged parts of the brain, which is protected by a national and international patent. CONCLUSION: The paper presents a comprehensive review of the current options for compensating for lost vision at the level of the cerebral cortex and a proposal for a new non-invasive method of stimulating the functional neurons of the visual cortex.


Assuntos
Encéfalo , Córtex Visual , Humanos , Encéfalo/fisiologia , Visão Ocular , Transtornos da Visão , Neurônios
16.
Curr Biol ; 34(3): R89-R91, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38320479

RESUMO

The discovery of melanopsin cells in the retina might render the standard model of human color perception incomplete. Measurements made with a technically advanced visual display address this question and point to a new role for the melanopsin system.


Assuntos
Células Fotorreceptoras Retinianas Cones , Células Ganglionares da Retina , Humanos , Estimulação Luminosa , Visão Ocular , Retina , Opsinas de Bastonetes
17.
Sci Rep ; 14(1): 2735, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302540

RESUMO

We analyze the visual perception task that home plate umpires (N = 121) perform calling balls and strikes (N = 3,001,019) in baseball games, focusing on the topics of perceptual learning and bias in decision-making. In the context of perceptual learning, our results show that monitoring, training, and feedback improve skill over time. In addition, we document two other aspects of umpires' improvement that are revealing with respect to the nature of their perceptual expertise. First, we show that biases in umpires' decision-making persist even as their overall accuracy improves. This suggests that bias and accuracy are orthogonal and that reduction of bias in decision-making requires interventions aimed specifically at this goal. Second, we measure a distinct difference in the rate of skill improvement between older and younger umpires. Younger umpires improve more quickly, suggesting that the decision task umpires engage in becomes routinized over time.


Assuntos
Beisebol , Percepção Visual , Visão Ocular , Aprendizagem , Psicofísica , Tomada de Decisões
18.
Sci Rep ; 14(1): 2820, 2024 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-38307901

RESUMO

This paper proposes and executes an in-depth learning-based image processing approach for self-picking apples. The system includes a lightweight one-step detection network for fruit recognition. As well as computer vision to analyze the point class and anticipate a correct approach position for each fruit before grabbing. Using the raw inputs from a high-resolution camera, fruit recognition and instance segmentation are done on RGB photos. The computer vision classification and grasping systems are integrated and outcomes from tree-grown foods are provided as input information and output methodology poses for every apple and orange to robotic arm execution. Before RGB picture data is acquired from laboratory and plantation environments, the developed vision method will be evaluated. Robot harvest experiment is conducted in indoor as well as outdoor to evaluate the proposed harvesting system's performance. The research findings suggest that the proposed vision technique can control robotic harvesting effectively and precisely where the success rate of identification is increased above 95% in case of post prediction process with reattempts of less than 12%.


Assuntos
Robótica , Frutas , Processamento de Imagem Assistida por Computador , Força da Mão , Visão Ocular
19.
Invest Ophthalmol Vis Sci ; 65(2): 22, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345555

RESUMO

Purpose: To examine whether the age-related increase in visual field dependence persists in older adults with central field loss (CFL). Methods: Twenty individuals with CFL were grouped into participants with age-related binocular CFL (CFL, n = 9), age-related monocular CFL/relative scotomata (mCFL, n = 8), and CFL occurring at a young age (yCFL, n = 3). Seventeen controls were age-matched to the older CFL groups (OA) and three to the yCFL group (yOA). Participants judged the tilt direction of a rod presented at various orientations under conditions with and without a visual reference. Visual field dependence was determined as the difference in judgment bias between trials with and without the visual reference. Visual field dependence was examined between groups and relative to visual acuity and contrast sensitivity. Results: All older groups performed similarly without the visual reference. The CFL group showed greater visual field dependence than the OA group (Mann-Whitney U test; U = 39, P = 0.045). However, there was no group difference when considering all three older groups (Kruskal-Wallis ANOVA; H(2, N = 34) = 4.31, P = 0.116). Poorer contrast sensitivity correlated with greater visual field dependence (P = 0.017; ρ = -0.43). Conclusions: Visual field dependence persists in older adults with CFL and seems exacerbated in those with dense binocular scotomata. This could be attributed to the sensitivity of the spared peripheral retina to orientation and motion cues. The relationship with contrast sensitivity further suggests that a decline in visual function is associated with an increase in visual field dependence beyond the effects of normal aging. These observations can guide tailored care and rehabilitation in older adults with CFL.


Assuntos
Escotoma , Campos Visuais , Humanos , Idoso , Escotoma/etiologia , Visão Ocular , Acuidade Visual , Sensibilidades de Contraste
20.
Optom Vis Sci ; 101(1): 12-24, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350054

RESUMO

ABSTRACT: Detailed clinical assessment is critical to allow sensitive evaluation of the eye and its management. As technology advances, these assessment techniques can be adapted and refined to improve the detection of pathological changes of ocular tissue and their impact on visual function. Enhancements in optical medical devices including spectacle, contact, and intraocular lenses have allowed for a better understanding of the mechanism and amelioration of presbyopia and myopia control. Advancements in imaging technology have enabled improved quantification of the tear film and ocular surface, informing diagnosis and treatment strategies. Miniaturized electronics, large processing power, and in-built sensors in smartphones and tablets capacitate more portable assessment tools for clinicians, facilitate self-monitoring and treatment compliance, and aid communication with patients. This article gives an overview of how technology has been used in many areas of eye care to improve assessments and treatment and provides a snapshot of some of my studies validating and using technology to inform better evidence-based patient management.


Assuntos
Distinções e Prêmios , Lentes Intraoculares , Presbiopia , Procedimentos Cirúrgicos Refrativos , Humanos , Visão Ocular
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