Practice Effects on Reaction Time for Peripheral and Central Visual Fields

2002 ◽  
Vol 95 (3) ◽  
pp. 747-751 ◽  
Author(s):  
Soichi Ando ◽  
Noriyuki Kida ◽  
Shingo Oda

The present study examined whether EMG-RT (KT) for a key press to stimulus in peripheral and central visual fields decreases with practice. 16 male students were divided into two groups, one practicing using peripheral vision, the other practicing using central vision. Before and after practice, RT was measured for peripheral and central visual fields. Each group practiced three blocks of 25 trials five days a week for three weeks. RT for peripheral and central visual fields decreased with practice. Practice effects on RT for the peripheral visual field extended to RT for the central visual field, and vice versa. It is suggested that the transfer may reflect the decrease in the central nervous system's processing time in common between two RT tasks.

2019 ◽  
Vol 4 (4) ◽  
pp. 56-60
Author(s):  
M. M. Bikbov ◽  
O. I. Orenburkina ◽  
A. E. Babushkin

This review presents the characteristics and results of clinical studies of patients with age-related macular degeneration implanted with the developed for this purpose first macular IOL – intraocular macular telescope (IMT). This lens was designed specifically for patients with the most severe or terminal form of age-related macular degeneration and is designed for monocular implantation to provide central vision while maintaining peripheral vision of the paired eye, which is important for maintaining the balance and orientation of patients. This device allows patients to see both in dynamic and static situations in the near, intermediate and far ranges. The disadvantages of this lens are a decrease in the visual field and depth of focus (which excludes its bilateral implantation), the need for a large (10–12 mm) incision for implantation, which can cause an increase in corneal astigmatism and the risk of complications, in particular, the pupillary block with an increase in intraocular pressure. There are also difficulties in the study of the fundus after its implantation to assess the small changes in the macula or to identify possible postoperative complications after cataract surgery (macular oedema, etc.). Also after the implantation of this lens, there is need for special programs of visual rehabilitation. The patient’s commitment to the rehabilitation measures for the adaptation of the central visual field of the operated eye with the peripheral vision of the second eye is crucial for success of the IMT macular telescope implantation procedure.


Author(s):  
William A. Schaudt ◽  
Kristin J. Caufield ◽  
Brian P. Dyre

We examined whether flight-control performance might be improved by presenting airspeed information to peripheral areas of the visual field using virtual head-up displays (HUDs), and whether participants process these displays using peripheral, rather than central, vision. We found that, compared to a standard HUD speed indicator, a peripherally located virtual speed indicator produced superior altitude control and equivalent or better speed control. Participants' gaze dwell times were more concentrated on flight-path and altitude control information as compared to speed information for the virtual HUD speed indicator. Gaze patterns showed that participants processed the virtual speed indicator with peripheral vision while they needed to directly fixate the traditional military standard HUD speed indicator in central vision. We believe the virtual display allowed participants to acquire speed information in a manner consistent with naturally-evolved orienting processes and therefore reduced central visual field load, attentional demand, and overall mental workload, freeing resources for better flight-path control.


2007 ◽  
Vol 17 (4) ◽  
pp. 534-537 ◽  
Author(s):  
A. Perdicchi ◽  
M. Iester ◽  
G. Scuderi ◽  
S. Amodeo ◽  
E.M. Medori ◽  
...  

Purpose To make a visual field retrospective analysis on a group of patients with primary open angle glaucoma (POAG) and to evaluate whether different refractive errors could have different progression of the 30° central sensitivity. Methods A total of 110 patients with POAG (52 men and 58 women) were included in the study. All the patients were divided into four subgroups based on the refractive error. The visual field of all the included patients was assessed by an Octopus 30° central visual field every 6 months, for a total of 837 visual fields examined. The resulting data were analyzed by PERIDATA for Windows 1.7 TREND function. Mean defect (MD) and loss variance (LV) were considered for the analysis. Results At the first examination, 82% of eyes showed a global decrease of differential light sensitivity (MD >2 dB) and in 67% the distribution of the defect was nonhomogeneous (LV >6 dB). The analysis of variance for subgroups showed a more significant decrease of MD in highly myopic patients. A linear regression analysis highlighted a statistically significant change in time of MD in 36% and of LV in 34% of the eyes studied. Highly myopic patients had the highest (p<0.01) percentage of change of MD and LV (46% and 42%, respectively). Among the four subgroups, there was no difference in progression of MD decrease in time. Conclusions These results showed that after 5 years of glaucoma, the visual field was altered in most of the eyes examined (82%) and that in 67% of cases, its defect was nonhomogeneous and worsened with the increase of myopia. The regression linear analysis of visual field changes in time showed a progressive increase of MD and LV in approximately one third of all the eyes examined.


2020 ◽  
Author(s):  
Luiza Kirasirova ◽  
Vladimir Bulanov ◽  
Alexei Ossadtchi ◽  
Alexander Kolsanov ◽  
Vasily Pyatin ◽  
...  

AbstractA P300 brain-computer interface (BCI) is a paradigm, where text characters are decoded from visual evoked potentials (VEPs). In a popular implementation, called P300 speller, a subject looks at a display where characters are flashing and selects one character by attending to it. The selection is recognized by the strongest VEP. The speller performs well when cortical responses to target and non-target stimuli are sufficiently different. Although many strategies have been proposed for improving the spelling, a relatively simple one received insufficient attention in the literature: reduction of the visual field to diminish the contribution from non-target stimuli. Previously, this idea was implemented in a single-stimulus switch that issued an urgent command. To tackle this approach further, we ran a pilot experiment where ten subjects first operated a traditional P300 speller and then wore a binocular aperture that confined their sight to the central visual field. Visual field restriction resulted in a reduction of non-target responses in all subjects. Moreover, in four subjects, target-related VEPs became more distinct. We suggest that this approach could speed up BCI operations and reduce user fatigue. Additionally, instead of wearing an aperture, non-targets could be removed algorithmically or with a hybrid interface that utilizes an eye tracker. We further discuss how a P300 speller could be improved by taking advantage of the different physiological properties of the central and peripheral vision. Finally, we suggest that the proposed experimental approach could be used in basic research on the mechanisms of visual processing.


i-Perception ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 204166952110584
Author(s):  
Tristan Jurkiewicz ◽  
Romeo Salemme ◽  
Caroline Froment ◽  
Laure Pisella

Following superior parietal lobule and intraparietal sulcus (SPL-IPS) damage, optic ataxia patients underestimate the distance of objects in the ataxic visual field such that they produce hypometric pointing errors. The metrics of these pointing errors relative to visual target eccentricity fit the cortical magnification of central vision. The SPL-IPS would therefore implement an active “peripheral magnification” to match the real metrics of the environment for accurate action. We further hypothesized that this active compensation of the central magnification by the SPL-IPS contributes to actual object’ size perception in peripheral vision. Three optic ataxia patients and 10 age-matched controls were assessed in comparing the thickness of two rectangles flashed simultaneously, one in central and another in peripheral vision. The bilateral optic ataxia patient exhibited exaggerated underestimation bias and uncertainty compared to the control group in both visual fields. The two unilateral optic ataxia patients exhibited a pathological asymmetry between visual fields: size perception performance was affected in their contralesional peripheral visual field compared to their healthy side. These results demonstrate that the SPL-IPS contributes to accurate size perception in peripheral vision.


1973 ◽  
Vol 37 (3) ◽  
pp. 720-722 ◽  
Author(s):  
A. Louise Sailor

This study was designed to test the effect of practice on the expansion of peripheral vision. 24 college speed reading students were tested for a measure of peripheral vision with a Lafayette Color Perimeter. Half of the Ss practiced detection of a white stimulus object for a period of 6 wk. Ss serving as controls assisted by moving the carrier into the visual field of an experimental partner. Analysis of variance showed significant increase in visual fields for all Ss, experimental and control. Attention factors and equipment used in the speed reading classes appear to account for these results.


2020 ◽  
Vol 14 ◽  
Author(s):  
Luiza Kirasirova ◽  
Vladimir Bulanov ◽  
Alexei Ossadtchi ◽  
Alexander Kolsanov ◽  
Vasily Pyatin ◽  
...  

A P300 brain-computer interface (BCI) is a paradigm, where text characters are decoded from event-related potentials (ERPs). In a popular implementation, called P300 speller, a subject looks at a display where characters are flashing and selects one character by attending to it. The selection is recognized as the item with the strongest ERP. The speller performs well when cortical responses to target and non-target stimuli are sufficiently different. Although many strategies have been proposed for improving the BCI spelling, a relatively simple one received insufficient attention in the literature: reduction of the visual field to diminish the contribution from non-target stimuli. Previously, this idea was implemented in a single-stimulus switch that issued an urgent command like stopping a robot. To tackle this approach further, we ran a pilot experiment where ten subjects operated a traditional P300 speller or wore a binocular aperture that confined their sight to the central visual field. As intended, visual field restriction resulted in a replacement of non-target ERPs with EEG rhythms asynchronous to stimulus periodicity. Changes in target ERPs were found in half of the subjects and were individually variable. While classification accuracy was slightly better for the aperture condition (84.3 ± 2.9%, mean ± standard error) than the no-aperture condition (81.0 ± 2.6%), this difference was not statistically significant for the entire sample of subjects (N = 10). For both the aperture and no-aperture conditions, classification accuracy improved over 4 days of training, more so for the aperture condition (from 72.0 ± 6.3% to 87.0 ± 3.9% and from 72.0 ± 5.6% to 97.0 ± 2.2% for the no-aperture and aperture conditions, respectively). Although in this study BCI performance was not substantially altered, we suggest that with further refinement this approach could speed up BCI operations and reduce user fatigue. Additionally, instead of wearing an aperture, non-targets could be removed algorithmically or with a hybrid interface that utilizes an eye tracker. We further discuss how a P300 speller could be improved by taking advantage of the different physiological properties of the central and peripheral vision. Finally, we suggest that the proposed experimental approach could be used in basic research on the mechanisms of visual processing.


i-Perception ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 204166952093840
Author(s):  
Li Zhaoping

Consider a gray field comprising pairs of vertically aligned dots; in each pair, one dot is white the other black. When viewed in a peripheral visual field, these pairs appear horizontally aligned. By the Central-Peripheral Dichotomy, this flip tilt illusion arises because top-down feedback from higher to lower visual cortical areas is too weak or absent in the periphery to veto confounded feedforward signals from the primary visual cortex (V1). The white and black dots in each pair activate, respectively, on and off subfields of V1 neural receptive fields. However, the sub-fields’ orientations, and the preferred orientations, of the most activated neurons are orthogonal to the dot alignment. Hence, V1 reports the flip tilt to higher visual areas. Top-down feedback vetoes such misleading reports, but only in the central visual field.


Perception ◽  
2020 ◽  
Vol 49 (12) ◽  
pp. 1348-1361
Author(s):  
Di Wu ◽  
Na Liu ◽  
Pengbo Xu ◽  
Kewei Sun ◽  
Wei Xiao ◽  
...  

Various glares can decrease visual performance and cause discomfort, thus increasing drivers’ risk for traffic accidents in real life. The current study aimed to systematically investigate glare sensitivity in the central and peripheral visual fields by measuring contrast sensitivity function (CSF) under nonglare, steady glare, and transient glare conditions. Nine observers with normal visual acuity in the dominant eye were enrolled. The CSF in central and peripheral vision (the 5° upper left visual field) was measured in a mesopic environment while the stimulus was displayed under three conditions: nonglare, steady glare, and transient glare. An orientation identification task was used to obtain the CSF. After the experiment, the observers were asked to report their level of discomfort in the presence of the glare. The area under the log CSF (AULCSF) and cut-off spatial frequency served as indicators of visual performance. In agreement with previous studies, both steady and transient glare reduced the AULCSF and cut-off frequency. However, the AULCSF and cut-off frequency were reduced more for central vision than for nearly peripheral vision. In addition, the extent of the decreases in the AULCSF and cut-off frequency was greater for steady glare than for transient glare; in contrast, more discomfort was associated with transient glare than steady glare.


Author(s):  
Hiroshi Takahashi ◽  

This paper deals with the possibility of a new warning method for controlling drivers’ sensitivity for recognizing hazardous factors in the driving environment. The method is based on a visual warning cue in the peripheral vision, which is outside of the central vision. In the human visual field, the central and peripheral vision fields have different processing mechanisms. In this study, the presentation of visual cues in the peripheral vision field is intended to provide a soft visual warning without intrusive interference to the task performed in the central vision. The results of many experiments performed with a 27-in. monitor display showed that a blinking visual cue at a view angle of around 26° from the center provided a good visual stimulus in the peripheral vision without being overlooked or being annoying to the subjects. The subjects tended to perceive the visual stimulus in the peripheral vision field beginning at 60°. A visual cue moving from the outer vision field to the center vision was perceived at around 60° regardless of its speed. A preliminary design guideline for installing visual warnings in the peripheral vision field is proposed.


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