Text Font Affects Reading Speed at a Low Luminance but Not at a High Luminance

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 51-51
Author(s):  
D Yager ◽  
K Aquilante ◽  
R Plass
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Low Vision ◽  
Reading Speed ◽  
Visual Presentation ◽  
High Luminance ◽  
Low Luminance ◽  
Significant Difference ◽  
Simulation Results ◽  
Parameter Values

We are beginning a series of studies in which we shall investigate which characteristics of text fonts may be successful in allowing text to be read with different kinds of degradations that may be experienced by low-vision patients. As a first attempt to simulate one of the problems that certain patients might have, we measured reading speeds with two proportionally spaced fonts at a high photopic luminance (146 cd m−2) and at a very low luminance (0.146 cd m−2). We used the RSVP (rapid serial visual presentation) reading method, which eliminates the need for scanning eye movements. The two fonts were ‘Swiss’, a simple sans-serif font, and ‘Dutch’, a serif font similar to Times Roman, both presented at the 20/80 size; letters were white on black, with a contrast of 0.94. Subjects were young, normally sighted high-school and optometry-college students. The reading speed results from 47 subjects were as follows, for four conditions: high luminance, Swiss 531 and Dutch 540 words min−1; low luminance, Swiss 479 and Dutch 429 words min−1. At the high luminance, there is no significant difference between reading rates. There is a significant advantage for the Swiss font at the low luminance: p=0.005. There may be a significant difference in reading speed with different fonts when the patient's perceptions are degraded by disease and/or aging processes. Other parameters to be investigated with this method include contrast, size, blur, and visual field position. The simulation results will suggest parameter values to test on low-vision patients.

Does Inverting Text Improve Reading Performance in Homonymous Hemianopes?

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 77-77
Author(s):  
M R Baker ◽  
J Henderson ◽  
A Hill
Keyword(s):  
Eye Movements ◽  
Low Vision ◽  
Reading Speed ◽  
Leading Edge ◽  
Visual Field Loss ◽  
Reading Performance ◽  
Sensory Level ◽  
Eye Tracker ◽  
Cognitive Component ◽  
The Right

Anecdotal information from rehabilitation practice of reading performance and low-vision practice suggests that where right homonymous parafoveal field loss impairs reading at the visual-sensory level, an improvement in reading speed can be achieved by inverting the text. This is because whilst left-field loss is considered to impair return eye movements to the beginning of a line, right-field loss is considered to reduce the spatial size of the perceptual window and increase its temporal extent by prolonging fixations times, reducing the amplitudes of saccades to the right, and introducing frequent regressive saccades. Inverting the text was thought to reverse these effects as the leading edge of the perceptual window is ‘returned’ to the sighted field so that in-line saccades can be visually guided. Here we report that this does not appear to be the case. In our study we measured the eye movements of patients with right homonymous hemianopia and others with peripheral loss due to retinitis pigmentosa as well as normal controls using an infrared video eye-tracker. All groups display a similar proportional prolongation of fixations times, reduction of saccadic amplitude, and proportion of regressive saccades when asked to read inverted text, which suggests a cognitive component of impairment independent of visual field loss in right homonymous hemianopes.

Reading with Visual Field Defects

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 11-11 ◽  
Author(s):  
S Trauzettel-Klosinski
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Reading Ability ◽  
Reading Speed ◽  
Visual Fields ◽  
Zero Point ◽  
Normal Subjects ◽  
Visual Field Defects ◽  
Video Tape ◽  
Field Defects

The influence of different visual field defects on the reading performance was examined with potential adaptive strategies to improve the reading process in mind. By means of an SLO, the retinal fixation locus (RFL) was determined with the use of single targets and text, and eye movements scanning the text were recorded on video tape. Additionally, eye movements were monitored by an Infrared Limbus Tracker. Visual fields were assessed by the Tübingen Manual and/or automatic perimetry. Normal subjects, and patients with central scotomata, ring scotomata, and hemianopic field defects (HFD) were examined. The main pathological reading parameters were an increase of saccade frequency and regressions per line, and a decrease of reading speed. In patients with field defects involving the visual field centre, fixation behaviour is significant for regaining reading ability. In absolute central scotoma, the lost foveal function promotes eccentric fixation. The remaining problem is insufficient resolution of the RFL, which can be compensated for by magnification of the text. In patients with insufficient size of their reading visual field, due to HFD and ring scotoma, it is crucial that they learn to use a new RFL despite intact foveolar function. Preconditions for reading have been found to be: (1) sufficient resolution of the RFL, (2) a reading visual field of a minimum extent, and (3) intact basic oculomotor function. In patients with visual field defects involving the centre, a sensory-motor adaptation process is required: the use of a new RFL as the new centre of the visual field and as the new zero point for eye-movement coordinates.

In Congenital Nystagmats, Reading Text with Rapid Serial Visual Presentation (RSVP) Reduces Mean Eye Velocity

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 73-73
Author(s):  
K Aquilante ◽  
H Wyatt ◽  
D Yager
Keyword(s):  
Low Vision ◽  
Reading Speed ◽  
Visual Presentation ◽  
Congenital Nystagmus ◽  
Half Height ◽  
Full Page ◽  
Infrared Reflection ◽  
Reading Text ◽  
Eye Velocity ◽  
Made In

Most low-vision subjects read text faster from an RSVP display than they do with full PAGE reading. This result has been confirmed with a group of subjects with congenital nystagmus (Plass and Yager, 1995, paper presented at ARVO). The present experiment was intended to determine whether reading with RSVP also reduced the severity of the nystagmus, which may have contributed to the faster reading rates. Eye position and velocity of congenital nystagmats were recorded with an infrared reflection technique, sampled at 40 s−1. Recordings were made in three conditions: (1) passively viewing a blank computer monitor; (2) silently reading full PAGE text at a size of approximately four times Snellen acuity; (3) silently reading RSVP text at the same size, at about 200 words min−1. We found that: (1) in frequency histograms of instantaneous eye velocities at 25 ms intervals, the full width at half height was an average of 60% smaller for RSVP reading compared to PAGE; (2) with a window of ±5 to 20 deg s−1, depending on the subject's baseline eye velocity, the number of epochs that were at least 75 ms in length, and the total time in these epochs, were significantly greater during RSVP reading than during PAGE reading or viewing a blank screen. We conclude that reading with RSVP reduces nystagmus, and may contribute to greater reading speed.

Is the “Preferred” Color Temperature Transferable from Near-Vision to Ambient Home Lighting? An Exploratory Study with People Who Have Central Visual Field Loss

2020 ◽  
Vol 114 (6) ◽  
pp. 447-460
Author(s):  
Claude Vincent ◽  
Julie Bourassa ◽  
Nathalie Cimon ◽  
Paule Verville ◽  
Frédéric Dumont
Keyword(s):  
Visual Field ◽  
Low Vision ◽  
Reading Speed ◽  
Visual Impairments ◽  
Visual Field Loss ◽  
Color Temperature ◽  
Visual Comfort ◽  
Central Visual Field ◽  
Near Vision ◽  
At Home

Introduction: The literature supports the importance of adequate lighting for people with visual impairments, but little is known regarding ambient color temperature at home, and the evaluation process is not standardized. Thus, this study aimed to test a method for evaluating the preferred ambient color temperature, established with a near-vision assessment in clinic, and by using standardized tools to evaluate the effects at home for people with central visual field loss. Methods: An exploratory quasi-experimental study was conducted with three interventions and six observation times. A convenience sample of eight women and two men with central visual field loss, aged 64–91 years with visual acuity between 6/21 (20/69) and 6/48 (20/158), was recruited. Two certified low vision therapists realized evaluations with Minnesota Low-Vision Reading Test, International Reading Speed Texts, a Visual Comfort Scale, a Digital Light Meter LX1330B, and Home Environment Lighting Assessment. The LuxIQ and various illuminated magnifiers were used for clinical interventions. Home lighting interventions were individualized and aimed to apply participants’ preferred color temperature in a selected room. Results: The use of the LuxIQ and illuminated magnifiers showed positive effects in near-vision for all participants by increasing reading speed and visual comfort. Home lighting interventions in participants’ kitchen ( n = 4), living room ( n = 4), or office ( n = 2) also had beneficial effects on their visual comfort and ability to perform activities of daily living. The choice of preferred color temperature was transferable from near-vision to ambient lighting for all participants but one and varied widely. Discussion: Innovative preliminary data support the importance of ambient color temperature for people with visual impairments and suggest an efficient standardized evaluation method. Further research is needed to obtain statistically significant empirical evidence in this field. Implications for practitioners: It could be beneficial for low vision therapists to evaluate the individual ambient color temperature preferences of people with visual impairments by using standardized tools.

scholarly journals Electrophysiological Correlates of Character Transposition in the Left and Right Visual Fields

2021 ◽  
Vol 12 ◽  
Author(s):  
Er-Hu Zhang ◽  
Xue-Xian Lai ◽  
Defeng Li ◽  
Victoria Lai Cheng Lei ◽  
Yiqiang Chen ◽  
...  
Keyword(s):  
Visual Field ◽  
Semantic Processing ◽  
Visual Fields ◽  
Event Related Potentials ◽  
Visual Presentation ◽  
Right Visual Field ◽  
N400 Effect ◽  
Significant Difference ◽  
Related Potentials ◽  
Whole Word

This study examined the brain activity elicited by the hemispheric asymmetries and morpheme transposition of two-character Chinese words (canonical and transposed word) and pseudowords using event-related potentials (ERPs) with a dual-target rapid serial visual presentation (RSVP) task. Electrophysiological results showed facilitation effects for canonical words with centrally presented visual field (CVF) and right visual field (RVF) presentations but not with left visual field (LVF) presentations, as reflected by less negative N400 amplitudes. Moreover, more positive late positive component (LPC) amplitudes were observed for both canonical words and transposed words irrespective of the visual fields. More importantly, transposed words elicited a more negative N400 amplitude and a less positive LPC amplitude compared with the amplitudes elicited by canonical words for CVF and RVF presentations. For LVF presentations, transposed words elicited a less negative N250 amplitude compared with canonical words, and there was no significant difference between canonical words and transposed words in the N400 effect. Taken together, we concluded that character transposition facilitated the mapping of whole-word orthographic representation to semantic information in the LVF, as reflected by the N250 component, and such morpheme transposition influenced whole-word semantic processing in CVF and RVF presentations, as reflected by N400 and LPC components.

scholarly journals The Effect of Different Locations of Simulated Central Vision Scotoma on Quality of Reading

2017 ◽  
Vol 2 (6) ◽  
pp. 133
Author(s):  
Noor Halilah Buari ◽  
Muhammad Zahir Nur-Zahirah
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Reading Speed ◽  
Central Scotoma ◽  
Central Vision ◽  
Significant Difference ◽  
Text Reading ◽  
Printed Text ◽  
Extract Information

As a person read, the eyes move to extract information from the printed text. Reading became disturbed when obstructed by the scotoma. The effect of reading and eye movement were investigated between different locations of simulated central vision scotoma. The time to read the text and the eye movements were recorded and tracked among eleven participants. The reading speed showed a significant difference at different locations of central scotoma simulation. The presence of central scotoma affects the quality of reading as the eye moved slowly during reading in order to comprehend the text.

scholarly journals Using Eye Tracking to Assess Reading Performance in Patients with Glaucoma: A Within-Person Study

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Nicholas D. Smith ◽  
Fiona C. Glen ◽  
Vera M. Mönter ◽  
David P. Crabb
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Experimental Design ◽  
Eye Tracking ◽  
Visual Function ◽  
Reading Speed ◽  
Reading Performance ◽  
Mean Deviation ◽  
Reading Patterns ◽  
The Difference

Reading is often cited as a demanding task for patients with glaucomatous visual field (VF) loss, yet reading speed varies widely between patients and does not appear to be predicted by standard visual function measures. Thiswithin-personstudy aimed to investigate reading duration and eye movements when reading short passages of text in a patient’s worse eye (most VF damage) when compared to their better eye (least VF damage). Reading duration and saccade rate were significantly different on average in the worse eye when compared to the better eye (P<0.001) in 14 patients with glaucoma that had median (interquartile range) between-eye difference in mean deviation (MD; a standard clinical measure for VF loss) of 9.8 (8.3 to 14.8) dB; differences were not related to the size of the difference in MD between eyes. Patients with a more pronounced effect of longer reading duration on their worse eye made a larger proportion of “regressions” (backward saccades) and “unknown” EMs (not adhering to expected reading patterns) when reading with the worse eye when compared to the better eye. A between-eye study in patients with asymmetric disease, coupled with eye tracking, provides a useful experimental design for exploring reading performance in glaucoma.

Visual asymmetries during face encoding Increased dwell time and fixations in the upper and left hemifields

2018 ◽  
Author(s):  
Fatima Maria Felisberti
Keyword(s):  
Face Recognition ◽  
Eye Movements ◽  
Visual Field ◽  
Face Processing ◽  
Dwell Time ◽  
The Other ◽  
Environmental Cues ◽  
Reading Habits ◽  
The Right

Visual field asymmetries (VFA) in the encoding of groups rather than individual faces has been rarely investigated. Here, eye movements (dwell time (DT) and fixations (Fix)) were recorded during the encoding of three groups of four faces tagged with cheating, cooperative, or neutral behaviours. Faces in each of the three groups were placed in the upper left (UL), upper right (UR), lower left (LL), or lower right (LR) quadrants. Face recognition was equally high in the three groups. In contrast, the proportion of DT and Fix were higher for faces in the left than the right hemifield and in the upper rather than the lower hemifield. The overall time spent looking at the UL was higher than in the other quadrants. The findings are relevant to the understanding of VFA in face processing, especially groups of faces, and might be linked to environmental cues and/or reading habits.

Visual Field Accuracy and Eye Movement Direction: A Child's Eye View

1980 ◽  
Vol 50 (2) ◽  
pp. 631-636
Author(s):  
Evans Mandes
Keyword(s):  
Eye Movements ◽  
Visual Field ◽  
Eye Movement ◽  
Visual Fields ◽  
Movement Direction

Post-exposural eye movements were studied in 32 adults and 24 7-yr.-old children. Stimuli were binary figures exposed tachistoscopically in both visual fields simultaneously. The data showed significant correlations between direction of eye movement and locus of recognition for both children and adults. No significant differences were found in frequencies of eye movements of children and adults. The data are interpreted in terms of the facilitative effects of post-exposural eye movements upon perception for both groups.

scholarly journals Epidemiological Findings of Refractive Errors and Amblyopia among the Schoolchildren in Hatta Region of the United Arab Emirates

2021 ◽  
pp. 1-7
Author(s):  
Salam Chettian Kandi ◽  
Hayat Ahmad Khan
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
United Arab Emirates ◽  
Refractive Error ◽  
Screening Program ◽  
Low Vision ◽  
Refractive Errors ◽  
Vision Screening ◽  
Screening Programs ◽  
School Based

<b><i>Introduction:</i></b> Uncorrected refractive errors and amblyopia pose a major problem affecting schoolchildren. We had previously observed that many schoolchildren in the Hatta region presented to the ophthalmology clinic with uncorrected refractive errors and amblyopia, which led us to undertake this research. As per the WHO, the term “visual impairment” can be “low vision” or “blindness.” Based on the presenting vision, “low vision” is defined for children who have vision of &#x3c;6/18 to 3/60 or having visual field loss to &#x3c;20° in the better-seeing eye. Children defined to have “blindness” have presenting vision of &#x3c;3/60 or corresponding visual field of &#x3c;10°. <b><i>Purpose:</i></b> To estimate the magnitude of uncorrected refractive errors and amblyopia among the schoolchildren aged 6–19 years and to assess the efficacy of school-based refractive error screening programs in the Hatta region of the United Arab Emirates. <b><i>Methods:</i></b> An epidemiological, cross-sectional, descriptive study was conducted on the entire student population studying in the government schools of the region. Those who failed the Snellen visual acuity chart test and those who were wearing spectacles were evaluated comprehensively by the researcher in the Department of Ophthalmology of the Hatta Hospital. Data were entered in the Refractive Error Study in School Children (RESC) eye examination form recommended by the WHO, and were later transferred to Excel sheets and analyzed by SPSS. <b><i>Results:</i></b> 1,591 students were screened and evaluated from the end of 2016 to mid-2017. About 21.37% (<i>n</i> = 340) had impaired vision with 20.9% (<i>n</i> = 333) refractive errors, of which 58% were uncorrected. Among the refractive error group, 19% (64 subjects) had amblyopia (4% of total students). The incidence of low vision was 9.5% and blindness was 0.38%. Low vision was found to be 9.5% and blindness 0.38%, taking in to account presenting visual acuity rather than best-corrected visual acuity for defining low vision and blindness. <b><i>Conclusion:</i></b> A significant number of students were detected to have uncorrected refractive errors among the vision impaired group (59%, <i>n</i> = 197) despite a school-based vision screening program in place. Seventy-eight percent of the amblyopia cases (<i>n</i> = 50) were found to be in the 11–19 years age group. Noncompliance with optical corrections was the reason for the high number of cases. A rigorous vision screening program and refractive services, complimented with awareness among parents and teachers, are recommended.

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