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PurposeTo investigate the characteristics and rate of central visual field loss after optic disc hemorrhage (DH).DesignProspective cohort study.MethodsThree hundred forty-three eyes of 220 subjects who had ≥3 years of follow-up with a minimum of 5 visits with 10-2 and 24-2 visual field (VF) were recruited. Rates of 10-2 mean deviation (MD) loss in each hemifield and predefined zones were compared using linear mixed-effects models in DH and non-DH eyes. Clustered pointwise regression analysis was also used to define central VF progressors and compared with 24-2 VF loss using guided progression analysis.ResultsThirty-nine eyes with DH and 304 eyes without DH had a mean follow-up of 5.2 years. Eyes with DH had rates of 10-2 MD loss that were 3 times faster than non-DH eyes (mean difference -0.36 dB/year [95% confidence interval 0.54-0.18]; P < .001) and were 3.7 times more likely to progress (P=.002). A larger proportion of glaucomatous eyes showed central VF progression rather than peripheral VF progression in the DH group (30.8% vs. 20.5%) compared with the non-DH group (10.9% vs. 9.2%). In early glaucoma, the rate of 10-2 MD loss was 5.5 times faster in DH eyes than in non-DH eyes (P < .001). Superonasal and superotemporal central VF regions progressed more rapidly than other regions, especially in DH eyes.ConclusionCentral VF loss is accelerated in glaucoma eyes with DH and it corresponds topographically to the DH location. In patients with glaucoma with DH, one should consider supplementing 10-2 VFs with 24-2 VFS to monitor the disease.

The discovery of melanopsin as a third type of retinal photoreceptor, contributing to both perceptual vision and reflex light responses, represents a new opportunity to optimise the design of artificial light sources for practical applications and to generate experimental stimuli. In the case of emissive displays, multiprimary designs incorporating a cyan primary could be used to allow melanopic radiance to be controlled independent of colour and luminance. Here we explore the performance a five-primary (violet, cyan, green, yellow, red) display device and find an anomaly in colour appearance when the cyan primary is employed. The anomaly took the form of a reddish/pinkish tinge in the central visual field, consistent with descriptions of Maxwell’s spot. This effect was apparent in some full colour images and in uniform discs over a range of chromaticities. Its appearance in coloured discs correlated with differences in calculated colour coordinate between central and peripheral vision. A simulation indicated that inclusion of any primary with predominant output in the 470–500 nm range has the potential to produce such a discrepancy in central vs peripheral appearance. Applying an additional constraint in colour processing to reproduce naturally occurring differences in central vs peripheral colour coordinate eliminated appearance of the spot and produced acceptable colour images.

Population receptive field (pRF) analysis is a popular method to infer spatial selectivity of voxels in visual cortex. However, it remains largely untested how stable pRF estimates are over time. Here we measured the intersession reliability of pRF parameter estimates for the central visual field and near periphery, using a combined wedge and ring stimulus containing natural images. Sixteen healthy human participants completed two scanning sessions separated by 10–114 days. Individual participants showed very similar visual field maps for V1-V4 on both sessions. Intersession reliability for eccentricity and polar angle estimates was close to ceiling for most visual field maps (r>.8 for V1-3). PRF size and cortical magnification (CMF) estimates showed strong but lower overall intersession reliability (r≈.4–.6). Group level results for pRF size and CMF were highly similar between sessions. Additional control experiments confirmed that reliability does not depend on the carrier stimulus used and that reliability for pRF size and CMF is high for sessions acquired on the same day (r>.6). Our results demonstrate that pRF mapping is highly reliable across sessions., Highlights • We assess the intersession reliability of population receptive field (pRF) estimates. • Reliability of visual field position estimates in V1-3 is excellent (r >.8). • Reliability of pRF size and local cortical magnification factor are good (r≈.3-.6), especially when tested on the same day (r>.6). • Natural images are an effective stimulus for visual field mapping.

The ability to detect visual targets in complex background varies across individuals and are affected by factors such as stimulus saliency and top-down attention. Here, we investigated how the saliency of visual background (naturalistic cartoon video vs. blank screen) and top-down attention (single vs. dual tasks) separately affect individual ability to detect visual targets. Behaviorally, we found that target detection accuracy decreased and reaction time elongated when the background was salient or during dual tasking. The EEG response to visual background was recorded using a novel stimulus tagging technique. This response was strongest in occipital electrodes and was sensitive to background saliency but not dual tasking. In contrast, the event-related potential (ERP) evoked by the visual target was strongest in central electrodes, and was affected by both background saliency and dual tasking. With a cartoon background, the EEG responses to visual targets, presented in the central visual field, and the EEG responses to peripheral visual background could both predict individual target detection performance. When these two responses were combined, better prediction was achieved. These results suggest that neural processing of visual targets and background jointly contribute to individual visual target detection performance.

Microperimetry, also referred to as fundus perimetry or fundus-driven perimetry, enables simultaneous acquisition of visual sensitivity and eye movement data. We present sensitivity data collected from 60 participants with normal vision using gaze-contingent perimetry. A custom designed spatially dense test grid was used to collect data across the visual field within 13° of fixation. These data are supplemental to a study in which we demonstrated a spatial interpolation method that facilitates comparison of acquired data from any set of spatial locations to normative data and thus screening of individuals with both normal and non-foveal fixation “Methods for normative data comparison in gaze-contigent microperimetry” (Denniss and Astle, 2016) [1].

Background Driving is a highly demanding task which presents itself with various unpredictable and potentially hazardous situations. The failure to visually scan the driving environment and strategically search for potential road hazards, can be considered as unsafe driving practices. Little is known about how licensed drivers with Autism Spectrum Disorder (ASD) visually scan the roads while driving. The present study assessed the visual scanning and fixation patterns of drivers with and without ASD during a simulated drive. Methods Twenty-eight licensed drivers between the age of 18–40 years old, including 14 drivers with ASD (male = 13) driving at least 2 h per week participated in a simulated drive with 14 matched controls. Psychometric profiles and visual scanning patterns on various objects of interest were analysed between groups. Results Drivers with ASD were found to fixate and spend significantly more time focusing on the central visual field and less time scanning where hazards potentially emerge. They also tended to allocate less visual attention on social stimuli (i.e., involving a person), and failed to stop in time at the red lights. Psychometric profiles confirmed poorer visual scanning and motor processing speed but less risk-taking behaviour in drivers with ASD. Conclusion Licensed drivers with ASD were found to allocate visual attention differently compared to licensed drivers without ASD. Poor scanning patterns with an over-focus on the road ahead and less scanning of the road side and periphery may possibly result in unsafe driving. However, risk-taking behaviour was not prevalent in these drivers. Effective visual scanning strategies could be incorporated in the driver training of individuals with ASD.

Vision is of paramount importance in regulating adaptive gait. Using three-dimensional motion analysis, the current study investigated how central visual field loss (CFL) affects step ascent. Ten patients with chronic CFL (77 ± 10 years) and 13 visual normal participants (72 ± 6 years) walked up to and ascended a single step (of varying height). Movement kinematics assessed the period immediately prior to and during step ascent. Compared to visual normal participants, patients with CFL exhibited a lower lead foot horizontal crossing velocity, increased lead limb swing time and increased head flexion (looking down at more immediate areas of the ground/step). They also took longer to initiate the step up, transfer weight to the lead foot upon landing on the upper level and increased trail limb swing time when negotiating the medium and high step height. Increased variability was also shown in a number of dependent measures. Data indicate that during step ascent, patients with CFL exhibit a cautious stepping strategy when compared to visual normal participants. This cautious strategy becomes increasingly evident when negotiating higher step heights, as shown by an increased planning time prior to entering the relatively unstable period of single support during the step up. The increased variability among CFL patients increases their likelihood of experiencing dynamic instability and falling during step ascent.

We compared photopic and scotopic multifocal pupillographic stimuli in age-related macular degeneration (AMD). Both eyes of 18 normal and 14 AMD subjects were tested with four stimulus variants presented at photopic and 126 times lower luminances. The multifocal stimuli presented 24 test regions/eye to the central 60°. The stimulus variants had two different check sizes, and when presented either flickered (15 Hz) for 266 ms, or were steady for 133 ms. Mean differences from normal of 5 to 7 dB were observed in the central visual field for both photopic and scotopic stimuli (all p < 0.00002). The best areas under receiver operating characteristic plots for exudative AMD in the photopic and scotopic conditions were 92.9 ± 8.0 and 90.3 ± 5.7% respectively, and in less severely affected eyes 83.8 ± 9.7% and 76.9 ± 8.2%. Damage recorded at photopic levels was possibly more diffusely distributed across the visual field. Sensitivity and specificity was similar at photopic and scotopic levels.

In neonatal intensive care units, newborn can be exposed to stress, which can damage the early development of his visual function. Being aware of the different processes of the complex visual system (embryogenesis, neuronal organization, neurosensory visual development) enables to propose practical recommendations to prevent early injures on the development of foetus and newborn visual system to limit the use of drugs that produce central nervous system depression, to respect sleep and cyclization of the light (darkness periods), to reduce strong stimuli (bright light, intense noise, pain), and to stimulate visual experience with various objects in the central visual field.

The perceived contrast of a central stimulus can be decreased (surround suppression) or increased (surround facilitation) by the presence of surround stimuli. In this report we examined center-surround interactions in foveal and peripheral vision using contrast-matching tasks. We found that: (1) surround suppression became markedly stronger as the center-surround stimulus was moved toward the periphery; (2) surround facilitation diminished in the periphery; and (3) the suppression in the periphery was less orientation- and frequency-specific than that in the fovea, so that significant suppression was induced even when the central and surround gratings had very different orientations and spatial frequencies. The different center-surround interactions in the fovea and periphery can not be accounted for by cortical magnification, suggesting that center-surround interactions in the fovea and periphery are incommensurable and play different functional roles in human image processing.

PURPOSE: To compare the results of peripheral kinetic visual field testing and central static perimetry for patients enrolled in the Optic Neuritis Treatment Trial to determine (1) whether loss and recovery of visual field sensitivity in the far periphery was different from that observed in the central visual field and (2) whether the far peripheral visual field provided additional useful information that was not available in the central visual field results. METHODS: Both affected and fellow eyes of 448 patients with optic neuritis in the Optic Neuritis Treatment Trial were evaluated according to the trial protocol during the patients' first 3 years in the study. Central static visual field tests were performed with program 30-2 on the Humphrey Field Analyzer, and peripheral kinetic testing consisted of plotting the I 3e and II 4e isopters on the Goldmann perimeter. Both test procedures were conducted according to the trial protocols, and quality control assessments and clinical evaluations were performed on all the visual fields. RESULTS: For both affected and fellow eyes at all 11 visits, there was a greater number of abnormal visual fields in the central static perimetry results than in the peripheral kinetic data. Only 2.9% of affected eyes had an abnormal peripheral visual field with a normal Humphrey mean deviation during year 1. At baseline, 97.1% of affected eyes had an abnormal Humphrey mean deviation on central static testing, whereas only 69.9% had abnormal peripheral kinetic visual fields. Approximately 80% of the I 3e and II 4e isopters for affected eyes that were abnormal at baseline were within normal limits at 30 days, but it took until week 19 for even 70% of the Humphrey mean deviations to return to normal. In addition, the II 4e isopters (more peripheral than the I 3e isopters) that were abnormal at baseline showed a somewhat greater percentage of improvement from baseline through day 30 than the abnormal I 3e isopters. Although this difference is statistically significant, it is probably not clinically significant. For visits after week 19, approximately 25% to 30% of affected eyes had an abnormal Humphrey mean deviation, whereas only 10% to 15% of peripheral kinetic fields were abnormal. CONCLUSIONS: For the affected eye in optic neuritis, the central visual field shows greater abnormalities than the far peripheral visual field. When the results obtained through Humphrey automated central static visual fields and Goldmann peripheral kinetic isopters are compared, the far periphery appears to recover more rapidly and more completely than the central field, at least in more severe cases of optic neuritis. In most cases, recovery in optic neuritis can probably be monitored effectively with automated perimetry of the central visual field alone. However, in cases of severe loss of the central visual field, a peripheral kinetic visual field obtained with a Goldmann perimeter may provide additional information about the patient's vision in the far periphery.

To examine the distribution of ERG-activity in the central visual field after local bleaching of the fovea, multifocal electroretinograms were recorded in eight normal volunteers before, during and after recurrent light exposure. During bleaching (90% bleached pigment), the response density (scalar product) of the foveal area (0-2 degrees eccentricity) decreased from 10.7 +/- 3.5 to 4.1 +/- 1.9 nV/degree2 (P < 0.001). The average activity in the extrafoveal macular area was unchanged, while the amplitudes were frequently (in 53 of 54 areas) enhanced at 5-30.5 degrees eccentricity. Here the average response density changed from 3.1 +/- 0.9 to 3.5 +/- 1.0 nV/degree2 (P < 0.001). A fast recovery of foveal responses after cessation of bleaching occurred. Besides a strong decrease of response in the directly bleached area, local bleaching led to enhanced activity mainly 3-27 degrees distant from the bleached area.

Background: With the increased use of a hand-held indirect lens and slit-lamp biomicroscopy for stereoscopic viewing of the optic nerve, the authors believe that an acquired pit of the optic nerve is more common than was recognized previously. This increased recognition has led to the awareness that the central visual field was affected frequently in the presence of such an acquired pit. Methods: The authors retrieved the charts of a series of 97 patients who had an acquired pit of the optic nerve during an 18-month period and retrospectively reviewed the automated visual fields associated with these pits using the Humphrey Visual Field Analyzer Programs 30-2 and 10-2 and looked for involvement of the central visual field. Results: In 81.7% of the acquired pits of the optic nerves, one of the central-most test points (3° from fixation) in the appropriate hemifield on the 30-2 format was depressed severely by Statpac II ( P P = 0.03). Conclusion: The authors showed that the presence of an acquired pit in an optic nerve damaged by glaucoma frequently is associated with a threat to fixation.

Two experiments were conducted which examined the influence of attention allocation and response factors upon the precue effect (i.e., RT difference between valid and invalid precue trials) for both peripheral and foveally delivered stimuli. Reaction stimuli (light emitting diode) differed only with respect to presentation location which was precued by the precue signal with 75% accuracy. Both a 1-Response and a 2-Response task were used. In the former case, only attention allocation was free to contribute to the precue effect while both attention allocation and response factors were potentially operational in the 2-Response condition. The results obtained revealed that both attention allocation and response factors made significant contributions to the spatial precue effect when the reaction stimuli were delivered parafoveally; however, only response factors contributed to this effect when the imperative stimuli were presented within the foveal area. It appears that either subjects do not allocate attention to precued locations when the reaction stimuli require only “luminance detection” and when they are presented foveally or that if they do so, RT is not altered by the presence or absence of attention.

Monocular eye-hand coordination was tested in a pointing experiment in the central and peripheral visual field of each eye of strabismic and anisometropic amblyopes, strabismic alternators and normal controls. In the normal controls, pointing was accurate in the central visual field. Towards the periphery, normal observers showed a varying amount of undershoot as well as increasing uncertainty. The pointing pattern was similar in the two eyes of these subjects. Increased uncertainty of pointing responses was found in most amblyopic eyes as compared to the dominant eyes. Three strabismic amblyopes and one strabismic alternator also had systematic pointing errors (i.e. systematic differences between pointing under the control of the dominant as compared to the nondominant eye). The pointing pattern was not uniform across the visual field in some of the Strabismics, but was composed of areas of larger and smaller pointing errors. Larger pointing errors (i.e. larger differences between the dominant and nondominant eyes) were usually found in the central visual field. These errors were not closely related to the angle of squint. The clinical history of the strabismics seems to be an important factor for the occurrence of pointing errors.

Purpose: To determine an optimal sector pattern of the central 30° visual field in glaucoma by mathematically analyzing the visual field data of primary open-angle glaucoma (POAG) without any assumption such as the retinal nerve fiber layer anatomy. Methods: One hundred three visual fields of the 30-2 program of the Humphrey Field Analyzer obtained from 103 POAG patients of early to moderately advanced stage were included. Based on the interpoint correlation of deviation of the measured threshold value from the age-corrected normal reference value (total deviation, STATPAC), test points of the 30-2 program were mathematically clustered using the VARCLUS procedure, a new clustering algorithm developed by the SAS Institute. The sector value, which summarizes the visual field performance of the clustered test points (sector), also was calculated. Results: The 30° central visual field was divided into 15 sectors consisting of at least 3 points. The distribution of sectors was compatible with the projection of nerve fiber layers. There was no sector extending over the horizontal meridian, but the sector pattern was not completely symmetrical around it. Linear regression analysis of the sector values against the mean deviation (STATPAC) suggested that the index is useful in following visual field performance of each sector. Conclusion: The sector pattern and sector values obtained were considered useful in studying the visual field data of glaucoma.

Objetivo: La luminancia del estímulo (L) y su área (A) están relacionados por la ecuación: LxAk=constante. Se evaluó el valor de k en 66 posiciones del campo visual central. Métodos: Se examinaron 10 ojos de 10 sujetos normales usando perimetría de umbral convencional en 66 posiciones del campo visual central usando la estrategia TOP y tamaños de estímulo Goldmann 4, 3,5, 3, 2,5, 1,9 en el perímetro PULSAR. Resultados: Como promedio, el valor de k aumentó linealmente desde el centro hacia la periferia, con una pendiente de 0,01 por grado en las 10 excentricidades analizadas (r=0,98, p

Purpose: An assessment of retinal function topographically in the affected eyes with central serous chorioretinopathy (CSC).Participants and Method: We recorded multifocal electroretimogram (mERG) in 5 patients with unilateral CSC, and analyzed the topographical properties in the central visual field (rings #1 + 2).Results: mERG amplitudes in the CSC eyes were significantly reduced compared with the fellow eyes, for P 1-N 1 (58.5 +/- 23.5%, p < 0.05) and for P 1-N 2 (47.5 +/- 15.0%, p < 0.05). mERG latencies in the CSC eyes were significantly increased compared with those in the fellow eyes, for N 1 (by 9.0 +/- 8.1%, p < 0.05) and for P 1 (by 8.4 +/- 7.0%, p < 0.05). mERG in the CSC eyes gradually recovered in the follow-up period. However, the responses did not recover to normal value during follow-up, even when the subretinal fluid disappeared ophthalmoscopically.Conclusions: These results show that a topographical analysis of the mERG is useful for clinical observation of CSC.

The visual properties of cells in the cat ventral lateral geniculate nucleus (LGV) identified antidromically from the pretectum and/or superior colliculus (projection cells) were studied in comparison with those of LGV neurons which could not be activated antidromically (non-projection cells). ON-phasic receptive fields (RFs) were relatively predominant in 27 projection cells, whereas ON-tonic RFs were found more commonly in the non-projection group. The distribution of the RF centers revealed a centroperipheral gradient of the visual field representation within the LGV that the central visual field was more densely organized.

This study deals with the distribution of corticopontine neurons in four of the lateral suprasylvian visual areas, the anteromedial, anterolateral, posteromedial and posterolateral areas. Following large injections of horseradish peroxidase-wheat germ agglutinin in the pontine nuclei, labelled cells were quantitatively mapped. The borders of the four areas were determined cyto- and myeloarchitectonically or from standard retinotopic maps presented in frontal sections (Tusa et al. , 1981). 50 Flat maps were constructed of each area showing the distribution of retrogradely labelled neurons. Maps of the retinotopic organization in the lateral suprasylvian visual areas (Palmer et al. , 1978; Tusa et al. , 1981) 29,50 were transferred to the flat maps. Thus, the density and number of labelled cells within each area and within smaller zones representing different visual field blocks could be determined. The average cell density (average number of labelled cells per mm 2 of flattened cortex) is highest in the anteromedial area. The average density in this area is higher than in areas 17,18 and 19. The total number of labelled cells is highest in the posteromedial area. The lateral syprasylvian visual areas together have a stronger pontine projection in terms of actual number of cells than each of areas 17, 18 and 19. [Data on areas 17, 18 and 19 from Bjaalie and Brodal (1983) and Bjaalie (1985).] 6,8 The four areas investigated have different internal distribution of corticopontine cells. The posteromedial and posterolateral areas have lower densities of labelled cells in the representations of the retinal central area than in the representations of the visual periphery. However, due to the enlarged cortical representations of central vision, the actual number of corticopontine cells per visual field block is higher in the cortex representing the central area; i.e. the central visual field region is moderately over-represented in the corticopontine projection from these areas. In the anteromedial and anterolateral areas, unlike in all other areas so far investigated, the cortical representations of the central visual field contain higher densities of corticopontine cells than the representations of the lower visual periphery. However, since the central area is only very weakly over-represented compared to the lower visual periphery in terms of cortical volume in these areas, the over-representation in the corticopontine projection of central vision compared to the lower visual periphery is fairly moderate. Thus, the over-representation of central vision in terms of number of corticopontine neurons seems to be of a fairly constant magnitude in all visual areas so far investigated (including areas 17, 18 and 19), even if the over-representation in terms of cortical volume varies dramatically between the various cortical visual areas.

We studied visual detection in 150 infants, 1- to 7-days old, by presenting single lines varying in width and location. We found that newborns detected a line only 8′ wide in the central visual field. Peripherally, they appeared to detect lines of 33′, 33′, and 1°6′ at 10°, 20°, and 30°, respectively. Thus, both the central retina and the peripheral retina appear to function at birth.

Layer V pyramidal cells of the cat lateral suprasylvian visual areas project to the pontine nuclei. Although all 6 of the suprasylvian visual areas project to the pons, the denset projections are from 3 areas: anterior medial lateral suprasylvian (AMLS), posterior medial lateral suprasylvian (PMLS) and ventral lateral suprasylvian (VLS). The organization of the corticopontine pathway from one of these areas (PMLS) suggests a disproportionate representation of the peripheral visual fields. This pattern of projection would serve to de-emphasize the central visual field.

We studied the fellow eyes of eyes with macular holes by fundus photography, fluorescein angiography, and central visual field testing. Eight of 37 fellow eyes (22%) observed for a minimum of 36 months developed macular holes. Fellow eyes initially classified as normal developed fewer macular holes than fellow eyes with initial pigment epithelial defects or cystic formation.

Summary Large lesions of the whole visual cortex (areas 17, 18 and 19) and small lesions (in most cases bilateral) of area 17 were made in adult cats, and the ensuing degeneration in the pontine nuclei was studied with the silver impregnation methods of Nauta and of Fink and Heimer. Most of the lesions were made by thermocoagulation. The main results are as follows. (1) The visual cortex as a whole projects onto several sharply delimited, mainly transverse bands in the rostral half of the pontine nuclei. The exact localization of these bands has been compared with the terminal areas of the corticopontine fibers from other cortical regions as determined by the present author. Only a modest degree of overlap is possible between the projection areas of the visual cortex and of the sensorimotor cortex. (2) All parts of area 17 project onto the pontine nuclei. The projection from middle parts (representing roughly the central visual field) is sparse, whereas it is heavy from rostral and caudal parts (representing peripheral parts of the visual field). (3) The total projection from area 17 covers the same pontine region as does the projection from the visual cortex as a whole (areas 17, 18 and 19). (4) A topical localization is present within the pontine projection from area 17. Rostral parts (representing the lower visual field) project more laterally within the pontine nuclei than do caudal parts (upper visual field). Medial and lateral parts of area 17 also project differently onto the pontine nuclei.