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1.
Invest Ophthalmol Vis Sci ; 60(14): 4858-4864, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31747686

RESUMO

Purpose: We investigate temporal synchrony within one eye and between both eyes in adults with amblyopia. Methods: Eight adult amblyopes (range, 19.88-27.81 years old; median, 22.86 years old) and 12 age-matched adults with normal vision (range, 21.2-50.30 years old; median, 23.78 years old) participated in the experiment. We showed two pairs of Gaussian blobs flickering at 1 Hz as visual stimuli, one pair with the same temporal phase modulation (i.e., the reference) and another pair with a distinct temporal phase (i.e., the signal). We employed the constant stimuli method to measure the minimum degree of temporal phase (temporal synchrony threshold), at which participants were able to discriminate the signal pair under binocular, monocular, and dichoptic viewing configurations. Results: The temporal synchrony threshold was different across the six configurations (P = 0.001). There was also an interaction between the configuration and the group (P = 0.004). The synchrony threshold was significantly higher in amblyopes than in controls under the configurations where two pairs of blobs were presented to the amblyopic eye (136.52 ± 50.19 vs. 97.08 ± 22.02 ms, P = 0.027) and where the paired blobs were presented to different eyes (163.15 ± 80.85 vs. 111.61 ± 22.46 ms, P = 0.049). The visual deficits in these two configurations were significantly correlated (r = 0.824, P = 0.012). Conclusions: The threshold for detecting temporal asynchrony increased when the stimuli were presented only to the amblyopic eye and when they were dichoptically presented to the amblyopic and fellow eyes.


Assuntos
Ambliopia/fisiopatologia , Transtornos da Percepção/fisiopatologia , Limiar Sensorial/fisiologia , Visão Binocular/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção de Movimento/fisiologia , Percepção Espacial/fisiologia , Análise Espaço-Temporal , Visão Monocular/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
3.
J. optom. (Internet) ; 12(3): 192-197, jul.-sept. 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-185370

RESUMO

Purpose: Visual evoked potentials (VEPs) provide important diagnostic information related to the functional integrity of the visual pathways. The aim of this study was to establish normative values of different components of pattern reversal VEPs on Iranian normal adult subjects. Methods: Monocular and binocular pattern reversal VEPs were recorded on 59 healthy participants (22.55 ± 3.79 years old) using the Roland RETI system for two check sizes of 15 and 60 min of arc. The measured VEP components were the latencies of N75, P100, N135 and amplitude of N75-P100. Results: Repeated measures ANOVA showed that viewing eye condition has a significant impact on the amplitude of N75-P100 (P < 0.001, F = 13.89). Also, the effect of check size on the latencies of N75, P100, N135, amplitude of N75-P100 (P ≤ 0.010), as well as the intraocular difference of P100 latency and amplitude N75-P100 (P = 0.007) was significant. More specifically, the amplitude of N75-P100 in both check sizes significantly differed between gender groups (P < 0.023). Conclusion: According to the results of this study, VEPs components are affected by the stimulus size, monocular and binocular recording conditions and gender. Therefore, it is necessary to determine the normative values of VEPs in each population, so that the results could be used in clinical studies


Objetivo: Los potenciales evocados visuales (PEV) aportan información diagnóstica importante relacionada con la integridad funcional de las vías visuales. El objetivo de este estudio fue establecer los valores normativos de los diferentes componentes de la reversión del patrón de PEV en adultos normales iraníes. Métodos: Se registraron los valores de reversión monocular y binocular del patrón de PEV en 59 participantes sanos (22,55 ± 3,79 años), utilizando el sistema Roland RETI para dos tamaños de comprobación de 15 y 60 min de arco. Los componentes medidos de PEV fueron las latencias de N75, P100, N135 y la amplitud de N75-P100. Resultados: La repetición de las medidas ANOVA reflejó que la situación del ojo de visión tiene un impacto significativo sobre la amplitud de N75-P100 (P < 0,001, F = 13,89). De igual modo, el efecto del tamaño de la comprobación de las latencias de N75, P100, N 135, la amplitud de N75-P100 (P ≤ 0,010), así como la diferencia intraocular de la latencia de P100 y la amplitud de N75-P100 (P = 0,007) fue significativo. Más específicamente, la amplitud de N75-P100 en ambos tamaños de comprobación difirió considerablemente entre los grupos de sexos (P < 0,023). Conclusión: Con arreglo a los resultados de este estudio, los componentes de los PEV se ven afectados por el tamaño del estímulo, las situaciones del registro monocular y binocular, y el sexo. Por tanto, es necesario determinar los valores normativos de los PEV en cada población, para poder utilizar los resultados en estudios clínicos


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Potenciais Evocados Visuais/fisiologia , Visão Binocular/fisiologia , Vias Visuais/fisiologia , Análise de Variância , Irã (Geográfico) , Tempo de Reação , Valores de Referência , Visão Monocular/fisiologia
4.
Neuron ; 103(1): 118-132.e7, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31147153

RESUMO

Animals use global image motion cues to actively stabilize their position by compensatory movements. Neurons in the zebrafish pretectum distinguish different optic flow patterns, e.g., rotation and translation, to drive appropriate behaviors. Combining functional imaging and morphological reconstruction of single cells, we revealed critical neuroanatomical features of this sensorimotor transformation. Terminals of direction-selective retinal ganglion cells (DS-RGCs) are located within the pretectal retinal arborization field 5 (AF5), where they meet dendrites of pretectal neurons with simple tuning to monocular optic flow. Translation-selective neurons, which respond selectively to optic flow in the same direction for both eyes, are intermingled with these simple cells but do not receive inputs from DS-RGCs. Mutually exclusive populations of pretectal projection neurons innervate either the reticular formation or the cerebellum, which in turn control motor responses. We posit that local computations in a defined pretectal circuit transform optic flow signals into neural commands driving optomotor behavior. VIDEO ABSTRACT.


Assuntos
Fluxo Óptico/fisiologia , Vias Visuais/citologia , Animais , Cerebelo/citologia , Cerebelo/fisiologia , Dendritos/fisiologia , Neurópilo/fisiologia , Neurópilo/ultraestrutura , Terminações Pré-Sinápticas/fisiologia , Formação Reticular/citologia , Formação Reticular/fisiologia , Células Ganglionares da Retina/fisiologia , Colículos Superiores/citologia , Colículos Superiores/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Vias Visuais/anatomia & histologia , Peixe-Zebra/fisiologia
5.
J Pediatr Ophthalmol Strabismus ; 56(3): 183-187, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31116867

RESUMO

PURPOSE: To describe a novel surgical technique for the treatment of monocular elevation deficit and report its short-term outcomes. METHODS: This was a prospective interventional case series. It was an institutional-based study of 5 patients with monocular elevation deficit. A single horizontal rectus muscle was transposed to 2 mm from the insertion of the superior rectus muscle along the spiral of Tillaux, augmenting it with a non-absorbable suture taken 8 mm behind its insertion. The main outcome measures were primary position hypotropia and elevation deficit at 8 months postoperatively. RESULTS: The mean age was 12.4 years (range: 6 to 26 years). Four patients underwent lateral rectus transposition and one underwent medial rectus transposition. Inferior rectus recession was done in all patients. The mean follow-up period was 8 months (range: 6 to 12 months). The mean hypotropia reduced from 34.6 prism diopters (PD) (range: 20 to 48 PD) preoperatively to 0.8 PD (range: -4 to 8 PD) at 8 months postoperatively. Additionally, 3 patients had exotropia with a mean of 12 PD (range: 2 to 20 PD) and 2 had esotropia with a mean of 28.5 PD (range: 12 to 40 PD); 1 underwent lateral rectus recession and 1 medial rectus recession. Three patients did not require any horizontal muscle surgery. The mean elevation deficit in abduction, straight up gaze, and adduction improved from 4.4, 3.2, and 2.8 to 2.0, 2.0, and 1.8, respectively. The mean depression deficit was 0.5. No adverse effects were noted. CONCLUSIONS: Single horizontal muscle transposition with inferior rectus recession allows sparing of at least one horizontal muscle and achieves adequate elevation effect and primary position deviation correction, at least in the short-term follow-up. [J Pediatr Ophthalmol Strabismus. 2019;56(3):183-187.].


Assuntos
Movimentos Oculares/fisiologia , Músculos Oculomotores/cirurgia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Estrabismo/cirurgia , Visão Monocular/fisiologia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Músculos Oculomotores/fisiopatologia , Período Pós-Operatório , Estudos Prospectivos , Estrabismo/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
Graefes Arch Clin Exp Ophthalmol ; 257(6): 1295-1301, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30989362

RESUMO

PURPOSE: To investigate the age-related course of best-corrected visual acuity in healthy eyes. METHODS: Two hundred participants (400 eyes) 25 to 74 years of age (114 females, 86 males) were investigated, 20 per 5-year age group. Best-corrected visual acuity was measured monocularly with the ETDRS 2000 charts at a distance of 4 m (Precision Vision, Woodstock, IL, USA). Strict exclusion and termination criteria were used. RESULTS: Visual acuity did not change between ages 25 and 54 years (mean of the better eyes, - 0.18 ± 0.05 logMAR). A significant age-related break-point in visual acuity was found at the ages of 55-59 years. For all age groups, the overall mean visual acuity was - 0.15 ± 0.06 logMAR for the better eyes and - 0.13 ± 0.06 logMAR for the worse eyes. There was no difference between the right and left eyes (- 0.14 ± 0.06 logMAR). The visual acuity was better in the right eye in 29% (n = 58) of the participants, better in the left eye in 32% (n = 64), and the same in both eyes in 39% (n = 78). From ages 25 to 64 years, neither the better nor the worse eye had a visual acuity worse than 0.0 logMAR. CONCLUSION: Best-corrected visual acuity was constantly high until the age of 54 years. An age-related break-point appeared at 55 to 59 years of age. Until age 64, a minimal angle of resolution smaller than 1 min of arc (visual acuity better 0.0 logMAR) can be expected in healthy eyes.


Assuntos
Envelhecimento/fisiologia , Visão Monocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Testes Visuais/métodos
7.
J Optom ; 12(3): 192-197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31028015

RESUMO

PURPOSE: Visual evoked potentials (VEPs) provide important diagnostic information related to the functional integrity of the visual pathways. The aim of this study was to establish normative values of different components of pattern reversal VEPs on Iranian normal adult subjects. METHODS: Monocular and binocular pattern reversal VEPs were recorded on 59 healthy participants (22.55±3.79 years old) using the Roland RETI system for two check sizes of 15 and 60min of arc. The measured VEP components were the latencies of N75, P100, N135 and amplitude of N75-P100. RESULTS: Repeated measures ANOVA showed that viewing eye condition has a significant impact on the amplitude of N75-P100 (P<0.001, F=13.89). Also, the effect of check size on the latencies of N75, P100, N135, amplitude of N75-P100 (P≤0.010), as well as the intraocular difference of P100 latency and amplitude N75-P100 (P=0.007) was significant. More specifically, the amplitude of N75-P100 in both check sizes significantly differed between gender groups (P<0.023). CONCLUSION: According to the results of this study, VEPs components are affected by the stimulus size, monocular and binocular recording conditions and gender. Therefore, it is necessary to determine the normative values of VEPs in each population, so that the results could be used in clinical studies.


Assuntos
Potenciais Evocados Visuais/fisiologia , Vias Visuais/fisiologia , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Irã (Geográfico) , Masculino , Tempo de Reação , Valores de Referência , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Adulto Jovem
8.
J Stroke Cerebrovasc Dis ; 28(6): 1495-1499, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30935808

RESUMO

INTRODUCTION: Atrial fibrillation (AF) is a major cause of ischemic stroke and Transient Ischemic Attack (TIA) and investigation for paroxysmal AF is recommended following an embolic brain event. In contrast, retinal ischemic monocular blindness is traditionally considered most linked to carotid artery disease (CAS) and investigating for AF is less vigilant. We aimed to determine the prevalence of AF in patients with ischemic monocular blindness. METHODS: Consecutive records of all patients presenting to a daily TIA clinic with transient or permanent ischemic monocular blindness were reviewed, January 2014-October 2016. RESULTS: Of 400 patients, 224 (56.0%) were male, mean age 64.5 years (SD 15.1). A total of 263 (66%) presented with transient and 137 (34%) with permanent ischemic monocular blindness. ECG was performed in 364 patients (91%) but only 211 (52%) had further cardiac monitoring. The vast majority (97.3%) had carotid imaging. Thirty-six patients (9%) were found to have AF while 53 (14%) had ipsilateral CAS. Median ABCD2 score was 1 in AF and non-AF groups. Only 55% of known AF patients were anticoagulated at presentation, despite all having CHADVASC2 score greater than or equal to 1. Patients with AF had more hypertension (P = .004), previous TIA (P = .002), previous stroke (P = .044) and ischemic heart disease (P = .022) with no difference in age (P = .791), diabetes (P = .563), smoking (P = .460) nor hypercholesterolaemia (P = .083). CONCLUSIONS: A total of 9% of patients with ischemic monocular blindness had AF. This is an underestimate, as only 53% of patients had prolonged cardiac monitoring. Known AF was suboptimally managed with only 55% receiving anticoagulation despite being eligible.


Assuntos
Fibrilação Atrial/epidemiologia , Cegueira/epidemiologia , Isquemia Encefálica/epidemiologia , Ataque Isquêmico Transitório/epidemiologia , Oclusão da Artéria Retiniana/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Visão Monocular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Amaurose Fugaz/epidemiologia , Amaurose Fugaz/fisiopatologia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Cegueira/diagnóstico , Cegueira/fisiopatologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatologia , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/fisiopatologia , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Recidiva , Oclusão da Artéria Retiniana/diagnóstico , Oclusão da Artéria Retiniana/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Adulto Jovem
9.
Atten Percept Psychophys ; 81(6): 1951-1961, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30887382

RESUMO

Crowding refers to the phenomenon of reduced recognition performance for peripherally presented targets that are flanked by similar stimuli. Crowding is known to vary with lateral distances (i.e., effects of target eccentricity and inter-character spacing). In the present experiment, we examined how crowding is affected by the distance of the stimuli in depth for natural viewing, i.e., for binocular observation of a real depth presentation. Superimposing the displays of two orthogonally arranged screens with a half-transparent mirror created real-depth presentation. We measured recognition performance of flanked compared to isolated targets that were presented at fixation depth, or in depths deviating from fixation depth (defocused). For both defocused directions (i.e., in front of and behind fixation depth), a near as well as a far distance from fixation was applied. Participants' task was to fixate a central cross at a constant distance (190 cm), and to indicate the gap position of an isolated or flanked Landolt ring that was presented at an eccentricity of 2°, on, in front of, or behind fixation depth. Results for natural binocular observation revealed increased crowding effects when stimuli were far compared to near from the fixation plane in depth. This resembles the common effect of eccentricity. Under monocular viewing, that is, without disparity information, crowding did not increase with increased depth distance. Thus, the result seemed to be an effect of binocular observation in real depth. This suggests that crowding in natural viewing might serve as a mechanism to stabilize and orient attention efficiently in three-dimensional space.


Assuntos
Percepção de Profundidade/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Aglomeração , Feminino , Humanos , Masculino , Adulto Jovem
10.
J Vis ; 19(3): 2, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30836382

RESUMO

Intercepting and avoiding moving objects requires accurate motion-in-depth (MID) perception. Such motion can be estimated based on both binocular and monocular cues. Because previous studies largely characterized sensitivity to these cues individually, their relative contributions to MID perception remain unclear. Here we measured sensitivity to binocular, monocular, and combined cue MID stimuli using a motion coherence paradigm. We first confirmed prior reports of substantial variability in binocular MID cue sensitivity across the visual field. The stimuli were matched for eccentricity and speed, suggesting that this variability has a neural basis. Second, we determined that monocular MID cue sensitivity also varied considerably across the visual field. A major component of this variability was geometric: An MID stimulus produces the largest motion signals in the eye contralateral to its visual field location. This resulted in better monocular discrimination performance when the contralateral rather than ipsilateral eye was stimulated. Third, we found that monocular cue sensitivity generally exceeded, and was independent of, binocular cue sensitivity. Finally, contralateral monocular cue sensitivity was found to be a strong predictor of combined cue sensitivity. These results reveal distinct factors constraining the contributions of binocular and monocular cues to three-dimensional motion perception.


Assuntos
Sinais (Psicologia) , Percepção de Profundidade/fisiologia , Percepção de Movimento/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Feminino , Humanos , Masculino , Matemática , Estimulação Luminosa/métodos , Campos Visuais/fisiologia
11.
Exp Brain Res ; 237(5): 1239-1255, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30850853

RESUMO

Proficient (fast, accurate, precise) hand actions for reaching-to-grasp 3D objects are known to benefit significantly from the use of binocular vision compared to one eye alone. We examined whether these binocular advantages derive from increased reliability in encoding the goal object's properties for feedforward planning of prehension movements or from enhanced feedback mediating their online control. Adult participants reached for, precision grasped and lifted cylindrical table-top objects (two sizes, 2 distances) using binocular vision or only their dominant/sighting eye or their non-dominant eye to program and fully execute their movements or using each of the three viewing conditions only to plan their reach-to-grasp during a 1 s preview, with vision occluded just before movement onset. Various kinematic measures of reaching and grasping proficiency, including corrective error rates, were quantified and compared by view, feedback and object type. Some significant benefits of binocular over monocular vision when they were just available for pre-movement planning were retained for the reach regardless of target distance, including higher peak velocities, straighter paths and shorter low velocity approach times, although these latter were contaminated by more velocity corrections and by poorer coordination with object contact. By contrast, virtually all binocular advantages for grasping, including improvements in peak grip aperture scaling, the accuracy and precision of digit placements at object contact and shorter grip application times preceding the lift, were eliminated with no feedback available, outcomes that were influenced by the object's size. We argue that vergence cues can improve the reliability of binocular internal representations of object distance for the feedforward programming of hand transport, whereas the major benefits of binocular vision for enhancing grasping performance derive exclusively from its continuous presence online.


Assuntos
Percepção de Profundidade/fisiologia , Atividade Motora/fisiologia , Desempenho Psicomotor/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Adulto , Fenômenos Biomecânicos , Retroalimentação Sensorial/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
12.
Gait Posture ; 69: 162-168, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30738275

RESUMO

BACKGROUND: The balance system continually integrates and processes diverse sensorimotor cues to maintain upright posture. Yet, little is known about how monocular visual cues may modulate the vestibular control of standing balance. RESEARCH QUESTION: To determine how visual cues, specifically monocular vision, modulate the vestibular-evoked myogenic and whole-body balance response. METHODS: Seventeen (12 female) healthy subjects (age: 24.8 ± 5.3years) were exposed to a random, continuous electrical vestibular stimulation (EVS) signal (±3.5 mA, 0-20 Hz). Subjects stood quietly during four experimental (no vision, non-dominant eye, dominant eye, binocular) conditions. The EVS-medial-lateral ground reaction force (ML GRF) acting on the body and EVS-medial gastrocnemius electromyography (EMG, bilateral) responses were evaluated in the frequency (coherence) and time (cumulant density) domains. RESULTS: Coherence was increased for no vision compared to binocular, dominant eye, and non-dominant eye visual cues, respectively, with the most pronounced increases occurring at lower frequencies. For cumulant density, the EVS-ML GRF medium-latency peak amplitude was increased 45, 26 and 18% with no vision compared to binocular, dominant eye and non-dominant eye visual cues, respectively (p < .05). The EVS-EMG medium-latency peak amplitude during no vision was greater than binocular (p < .05) for both gastrocnemii, but binocular and dominant eye monocular vision was not different (p > .05). The EVS-ML GRF and EVS-EMG (right medial gastrocnemius) medium-latency peak amplitude was greater for non-dominant eye monocular vision compared to binocular vision (p < .05). SIGNIFICANCE: Monocular visual cues, at least for the dominant eye, can depress the vestibular-evoked balance response at low frequencies akin to binocular vision with limited differences exhibited between dominant and non-dominant eye.


Assuntos
Sinais (Psicologia) , Equilíbrio Postural/fisiologia , Vestíbulo do Labirinto/fisiologia , Visão Monocular/fisiologia , Adulto , Eletromiografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
13.
J Vis ; 19(1): 3, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30630191

RESUMO

Neural processing of sensory input in the brain takes time, and for that reason our awareness of visual events lags behind their actual occurrence. One way the brain might compensate to minimize the impact of the resulting delays is through extrapolation. Extrapolation mechanisms have been argued to underlie perceptual illusions in which moving and static stimuli are mislocalised relative to one another (such as the flash-lag and related effects). However, where in the visual hierarchy such extrapolation processes take place remains unknown. Here, we address this question by identifying monocular and binocular contributions to the flash-grab illusion. In this illusion, a brief target is flashed on a moving background that reverses direction. As a result, the perceived position of the target is shifted in the direction of the reversal. We show that the illusion is attenuated, but not eliminated, when the motion reversal and the target are presented dichoptically to separate eyes. This reveals extrapolation mechanisms at both monocular and binocular processing stages contribute to the illusion. We interpret the results in a hierarchical predictive coding framework, and argue that prediction errors in this framework manifest directly as perceptual illusions.


Assuntos
Percepção de Movimento/fisiologia , Ilusões Ópticas/fisiologia , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Vias Visuais/fisiologia , Adulto , Análise de Variância , Humanos , Estimulação Luminosa/métodos
14.
J Korean Med Sci ; 34(4): e32, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30686953

RESUMO

Background: To objectively investigate accommodative response to various refractive stimuli in subjects with normal accommodation. Methods: This prospective, non-randomized clinical trial included 64 eyes of 32 subjects with a mean spherical equivalent -1.4 diopters (D). We evaluated changes in accommodative power, pupil diameter, astigmatic value, and axis when visual stimuli were applied to binocular, monocular (dominant eye, non-dominant eye, ipsilateral, and contralateral), and pinhole conditions. Visual stimuli were given at 0.25 D (4 m), 2 D (50 cm), 3 D (33 cm), and 4 D (25 cm) and accommodative response was evaluated using open view binocular autorefractor/keratometer. Results: The accommodative response to binocular stimulus was 90.9% of the actual refractive stimulus, while that of the monocular stimulus was 84.6%. The binocular stimulus induced a smaller pupil diameter than did the monocular stimulus. There was no difference in accommodative response between the dominant eye and non-dominant eye or between ipsilateral and contralateral stimuli. As the refractive stimuli became stronger, the absolute astigmatic value increased and the direction of the astigmatism axis became more horizontal. Pinhole glasses required 10%-15% less accommodative power compared with the monocular condition. Conclusion: Binocular stimuli enable more precise and effective accommodation than do monocular stimuli. Accommodative response is composed of 90% true accommodation and 10% pseudo-accommodation, and the refractive stimulus in one eye affects the contralateral eye to the same extent. This should be taken into account when developing guidelines for wearing smart glasses while driving, as visual stimulation is applied to only one eye, but far distance attention is constantly needed. Trial Registration: ClinicalTrials.gov Identifier: NCT03557346.


Assuntos
Acomodação Ocular/fisiologia , Visão Binocular , Visão Monocular , Adulto , Anisocoria/fisiopatologia , Feminino , Humanos , Masculino , Estimulação Luminosa , Estudos Prospectivos , Erros de Refração/fisiopatologia , Acuidade Visual , Adulto Jovem
15.
Pediatr Blood Cancer ; 66(5): e27623, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30688019

RESUMO

BACKGROUND: Monocular vision has been found to have a negative effect on children's motion processing and motor functions. Yet, knowledge of motor function of survivors of retinoblastoma (RB) with monocular vision (due to enucleation, for example) is limited. This study examined motor function and its relationship to visual-related and health-related quality of life (HRQOL) in survivors of RB with monocular vision. PROCEDURE: Parents of 27 survivors of RB, who underwent an enucleation of one eye resulting in monocular vision, and of 21 typically developing children between the ages of 6 and 12, were administered questionnaires relating to their children's motor function (DCDQ), as well as vision-related function (CVFQ) and HRQOL (PedsQL). RESULTS: Of the 27 survivors of RB, 7 (25.6%) were found to have difficulties in motor functions, compared with 1 (4.8%) child in the control group. The difficulties were faced mainly in daily function requiring control during movement, including jumping, running, and ball playing. Additionally, significant correlations were found between motor functions and children's QOL. Finally, survivors of RB with monocular vision were found to have lower QOL, specifically physical- and school-related QOL. CONCLUSION: Survivors of RB who have monocular vision have a higher rate of decreased motor function and lower QOL. These results point to a need for ongoing assessment of survivors of RB to allow timely detection of motor deficits and to institute appropriate therapeutic interventions.


Assuntos
Destreza Motora , Pais/psicologia , Qualidade de Vida , Neoplasias da Retina/fisiopatologia , Retinoblastoma/fisiopatologia , Sobreviventes/psicologia , Visão Monocular , Criança , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Neoplasias da Retina/psicologia , Retinoblastoma/psicologia , Inquéritos e Questionários
16.
Arq Bras Oftalmol ; 82(2): 98-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30698229

RESUMO

PURPOSE: To evaluate the clinical and surgical impacts of phenomena that could occur in intermittent exotropia. METHODS: The medical records of intermittent exotropia cases from 1991 to 2014 were retrospectively reviewed. All patients underwent a series of measures, including a protocol to assess monocular occlusion based on the propedeutics proposed by Kushner. RESULTS: Outdoor sensitivity was observed in 31% of patients with an undercorrection rate of 44% vs. 18% of cases with no outdoor sensitivity. After 1 h of monocular occlusion, 41% of all patients achieved an increase in deviation with an undercorrection rate of 40%, whereas 25% did not. CONCLUSION: The results show the importance of complete propedeutics, since there is a higher rate of late undercorrection in cases with outdoor sensitivity and increased deviation after occlusion.


Assuntos
Educação Pré-Médica/métodos , Exotropia/fisiopatologia , Exotropia/cirurgia , Acomodação Ocular/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Convergência Ocular/fisiologia , Feminino , Humanos , Lactente , Masculino , Registros Médicos , Pessoa de Meia-Idade , Período Pós-Operatório , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Visão Monocular/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
17.
PLoS One ; 14(1): e0210691, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30653560

RESUMO

PURPOSE: Using a head-mounted perimeter imo that can measure monocular sensitivity with both eyes open, we investigated the difference between monocular sensitivities measured with and without occlusion of the fellow eye and if the difference was influenced by eccentricity. METHODS: Using the perimeter imo, monocular sensitivities with/without occlusion and binocular sensitivity were measured and compared. Three test conditions for monocular sensitivity without occlusion were: with/without a fusional fixation target, and a binocular random single eye test in which the target was randomly presented to either eye and the examinee was not aware of the tested eye. Within the central 25° visual field (VF), 29 points located at the fovea and on the 45°, 135°, 225°, and 315° meridians with 3° intervals were tested. Differences among the four monocular sensitivities with/without occlusion were further evaluated at the fovea, within and beyond the central 5° VF. RESULTS: Sixteen visually normal volunteers (mean age, 28.6 ± 4.6 years) were included in this study. Except at the fovea, monocular sensitivities measured without occlusion were significantly higher than those with occlusion (P < 0.01). No significant difference was seen among the three monocular sensitivities without occlusion (P = 0.82). CONCLUSIONS: Except at the fovea, monocular sensitivities measured with and without occlusion significantly differed. This indicates that without occlusion, binocular interaction is activated and affects not only binocular sensitivity but also monocular sensitivity.


Assuntos
Campos Visuais/fisiologia , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
18.
Atten Percept Psychophys ; 81(3): 752-763, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30628033

RESUMO

The literature has long emphasized the neocortex's role in the tangled phasic-alertness and temporal-expectancy processes. In this work, we examined whether subcortical, monocular mechanisms have a functional role in these processes. This was done by assessing phasic alertness and temporal expectancy independently using a cue-target eye-of-origin manipulation. Participants performed target detection tasks in which a central cue and its ensuing peripheral target were each presented either to the same eye or to a different eye. In Experiment 1, phasic alertness, independent of temporal expectancy, was manipulated by presenting an alerting cue prior to the target presentation. The alerting effect elicited by the cue lasted for a longer duration when the cue and target were presented to the same eye than when they were presented to different eyes, indicating the involvement of subcortical regions in phasic alertness. In Experiment 2, the cue's temporal predictability regarding the target's onset time was manipulated by changing the cue-target interval's foreperiod distribution. A modulation in temporal expectancy was found when both the cue and the target were presented to the same eye, demonstrating the importance of subcortical mechanisms in temporal expectancy. Together, the results demonstrate that monocular channels are functionally involved in both phasic alertness and temporal expectancy. This study suggests that both phasic alertness and temporal expectancy are functionally dependent on monocular channels of the visual stream, and highlights the importance of direct examination of primitive, subcortical regions in higher cognitive functioning (e.g., temporal expectancy).


Assuntos
Nível de Alerta , Visão Monocular , Percepção Visual , Sinais (Psicologia) , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores de Tempo , Incerteza , Adulto Jovem
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