The Effect of Text Orientation, Visual Meridian, and Inter-Character Spacing on Word Identification in the Retinal Periphery

Perception ◽  
10.1068/p5118 ◽  
2003 ◽  
Vol 32 (11) ◽  
pp. 1339-1350 ◽  
Author(s):  
Alex Chaparro ◽  
Corrina Liao
Keyword(s):  
Word Identification ◽  
Major Axis ◽  
Visual Presentation ◽  
Lateral Interaction ◽  
Peripheral Retina ◽  
Horizontal Meridian ◽  
Identification Performance ◽  
Character Space ◽  
Retinal Periphery ◽  
The Right

Previous research has demonstrated that the masking effects of flankers about a target in the peripheral retina are not isotropic. Rather, regions of lateral interaction are ellipsoid in shape with the major axis oriented radially along a meridian through the fovea. This finding leads to the counterintuitive prediction that horizontal text positioned to the right of fixation might be read more slowly than similarly positioned text oriented diagonally or vertically. Similarly, vertically oriented text above fixation might be read more slowly than horizontally or diagonally oriented text above fixation. We investigated the effect of text orientation and inter-character spacing on word identification in the retinal periphery. Text was presented by rapid serial visual presentation. Words were centered 3° from fixation along four visual field meridians (VM) (right horizontal, upper-right diagonal, vertical, and upper-left diagonal). Regardless of VM identification, performance was best for horizontal text, declining slightly for orientations between +60° and −60° and declining more quickly for acute orientations. A weak effect of VM was observed for text with normal inter-character spacing. Performance was best for text centered along the horizontal meridian and declined slightly along the other VM. Finally, identification rates increased by ∼33 words min−1 with the addition of one character space between adjacent letters. The word-recognition processes are very tolerant of text orientation, exhibiting a modest decline for orientations within ±60° of horizontal regardless of VM.

scholarly journals Optical Coherence Tomography Angiography Features of Macular Epiretinal Neovascularization In Eales’ Disease: A Case Rreport

2021 ◽  
Author(s):  
Nora Alyousif ◽  
Abrar K. Alsalamah ◽  
Hassan Aldhibi
Keyword(s):  
Optical Coherence Tomography ◽  
Blood Vessels ◽  
Optic Disc ◽  
Optical Coherence Tomography Angiography ◽  
Internal Limiting Membrane ◽  
Peripheral Retina ◽  
Optical Coherence ◽  
Retinal Capillary ◽  
Eales Disease ◽  
The Right

Abstract Background: Eales disease primarily affects the peripheral retina. However, posterior involvement can be seen. Macular epiretinal neovascularization is not commonly seen in Eales disease. This report highlights the morphology and origin of macular epiretinal neovascularization (ERN) using multimodal retinal imaging, including optical coherence tomography angiography (OCTA). Results: A 35-year-old man with no history of systemic disorders presented with gradual decrease of vision in his left eye. Fundus examination of his right eye showed peripheral sclerosed blood vessels, neovascularization of the optic disc and elsewhere, and macular ERN. The view of the left fundus was limited by vitreous haemorrhage. Fluorescein angiography (FA), of the right eye showed widespread peripheral capillary nonperfusion and leakage of dye from the retinal neovascularization and macular ERN. Macular Spectral domain optical coherence tomography (SD-OCT) of the right eye showed an epiretinal membrane and the presence of epiretinal neovascular lesions extending above the internal limiting membrane towards the vitreous. Optical coherence tomography angiography (OCTA) showed multiple tiny blood vessels at the macula that arose from the superficial retinal capillary plexuses and extended toward the vitreous. The corresponding B-scan showed flow signal through these vessels and the signal extend above the internal limiting membrane. Systemic work-up was negative except for strongly positive tuberculin skin testing giving the classic diagnosis of Eales disease. Patient was started on empirical anti-tubercular therapy and oral corticosteroids. Scatter laser photocoagulation was applied to nonperfused retinal zones. Despite adequate scatter laser ablation, the ERN failed to regress fully. Conclusions: Macular ERN can be seen in cases of classic Eales disease. The origin of macular ERN in our case was shown to be from the superficial retinal capillary plexuses. We also noted the slower regression rate of macular ERN as compared to the major neovascularizations of the optic disc and peripheral retina. Further research is needed to establish the pathogenesis of ERN and its optimal management.

scholarly journals 2D IPO's for Constant Speed Lines, Curves, NURBS

2019 ◽  
Author(s):  
Valere Huypens
Keyword(s):  
Major Axis ◽  
Pulse Method ◽  
Constant Speed ◽  
Sampled Data ◽  
Reference Pulse ◽  
Production Manager ◽  
Definition Of ◽  
The Right ◽  
2D And 3D ◽  
Better Than

<div>Current constant speed IPO's, usually, use Sampled-data IPO's and constant speed lines use the </div><div>wrong initialized software DDA-ipo's, which make these IPO's unusable. The Bresenham- and </div><div>midpoint IPO's are non-constant speed reference pulse IPO's with bounded inaccuracy.</div><div>By adding an ultra-fast 3-lines algorithm "PRM-cs" to the actual midpoint or Bresenham algorithms, </div><div>we convert these midpoint-ipo's to very fast, constant speed, reference pulse IPO's. </div><div>This applies to 2D-lines, 3D-lines, 2D-curves and 2D-NURBS.</div><div>The PRM-cs measures, in real-time, the length of the discrete curve and the PRM-cs is completely new. </div><div>We define the best IPO, the major axis principle and the LSD-priority. </div><div>The major axis principle holds for the actual 3D-line IPO's. These IPO's are, generally, inaccurate, </div><div>but they can be updated to constant speed 3D-line IPO's, when the production manager agrees.</div><div>The Digital Geometric Geometry (DAG) defines the discrete lines globally, but this global </div><div>definition of a discrete 3D-line, gives discrete 3D-lines whose accuracy is much less than the </div><div>accuracy of the best discrete 3D-lines (e.g. 37% worse).</div><div>We describe the three causes of the inaccurate (imperfect) discrete 3D-lines. </div><div>All existing pulse-rate or PRM-ipo's use a wrong initialization, which deteriorates the accuracy. </div><div>We determine the right initialization for the new PRM-cs and the updated PRM-ipo. </div><div>We propose the benchmark-ipo "listSIM-ipo". This constant speed IPO can, also, be used in real-</div><div>time for every 2D- and 3D-curve. </div><div>The 3rd-degree Trident NURB shows that the constant speed reference pulse method is much </div><div>better than the existing sampled-data methods.</div>

A Method in Regression Equations for Forecasting the Movement of Typhoons

1960 ◽  
Vol 41 (3) ◽  
pp. 115-124 ◽  
Author(s):  
Griffith Wang
Keyword(s):  
Major Axis ◽  
Subtropical High ◽  
Regression Equations ◽  
High Cell ◽  
Typhoon Center ◽  
The Right

Based on six years (1950 through 1955) of typhoon data, three equations are formulated for the purpose of forecasting the movement of typhoons. In these equations, the following criteria at the 700-mb level are accounted for:(1) the contour height and its tendency at a point 10 deg of lat north of the typhoon center,(2) the contour height and its tendency at a point 10 deg of lat from the typhoon center and 90 deg to the right of its direction of motion,(3) the contour height and its tendency at a point 10 deg of lat from the typhoon center and 90 deg to the left of its direction of motion, and(4) the intensity and orientation of the major axis of a subtropical high cell which plays the role of steering the movement of the typhoon. Typhoon data collected during the years 1956 through 1958 are used for verification. With use of these equations, results of forecasting a 24-hr typhoon movement are found to be of practical value.

scholarly journals Reading sentences of words with rotated letters: An eye movement study

2018 ◽  
Vol 72 (7) ◽  
pp. 1790-1804 ◽  
Author(s):  
Hazel I Blythe ◽  
Barbara J Juhasz ◽  
Lee W Tbaily ◽  
Keith Rayner ◽  
Simon P Liversedge
Keyword(s):  
Target Word ◽  
Eye Movement ◽  
Word Identification ◽  
Low Frequency ◽  
Movement Control ◽  
Visual Presentation ◽  
Systematic Change ◽  
Relative Contribution ◽  
Total Fixation ◽  
Movement Study

Participants’ eye movements were measured as they read sentences in which individual letters within words were rotated. Both the consistency of direction and the magnitude of rotation were manipulated (letters rotated all in the same direction, or alternately clockwise and anti-clockwise, by 30° or 60°). Each sentence included a target word that was manipulated for frequency of occurrence. Our objectives were threefold: To quantify how change in the visual presentation of individual letters disrupted word identification, and whether disruption was consistent with systematic change in visual presentation; to determine whether inconsistent letter transformation caused more disruption than consistent letter transformation; and to determine whether such effects were comparable for words that were high and low frequency to explore the extent to which they were visually or linguistically mediated. We found that disruption to reading was greater as the magnitude of letter rotation increased, although even small rotations affected processing. The data also showed that alternating letter rotations were significantly more disruptive than consistent rotations; this result is consistent with models of lexical identification in which encoding occurs over units of more than one adjacent letter. These rotation manipulations also showed significant interactions with word frequency on the target word: Gaze durations and total fixation duration times increased disproportionately for low-frequency words when they were presented at more extreme rotations. These data provide a first step towards quantifying the relative contribution of the spatial relationships between individual letters to word recognition and eye movement control in reading.

scholarly journals 'Pseudoextinction': Asymmetries in simultaneous attentional selection

2016 ◽  
Author(s):  
Patrick T. Goodbourn ◽  
Alex O. Holcombe ◽  
Charlie Ludowici
Keyword(s):  
Visual Field ◽  
Rapid Serial Visual Presentation ◽  
Visual Presentation ◽  
Mixture Modeling ◽  
Attentional Selection ◽  
Right Visual Field ◽  
Temporal Precision ◽  
The Right

We report robust visual field asymmetries associated with selectingsimultaneous targets. One letter embedded in a rapid serial visual presentation(RSVP) of letters was encircled by a white ring, cueing it as the target to report. In some conditions, 2 RSVP streams were presented concurrently, and targets appearedsimultaneously in both. When only 1 stream was cued, performance was similarregardless of whether it was in the left or right visual field. Cueing 2 streams barelyaffected performance in the left stream, but performance in the right stream sufferedmarkedly. We term this phenomenon pseudoextinction, by analogy to pseudoneglectwhereby observers bisect lines to the left of center. Such attentional asymmetries areoften believed to originate from a processing imbalance between the 2 cerebralhemispheres. But pseudoextinction also occurred with vertically arrayed streams, withhigher efficacy in the superior than in the inferior stream. Mixture modeling of errorsindicated that pseudoextinction did not affect the temporal precision or latency ofselection episodes; rather, only the efficacy of selection suffered. These findings leadus to suggest that pseudoextinction arises because perceptual traces are activatedsimultaneously in a visual buffer but must be tokenized serially. Observers succeed inselecting simultaneous targets because trace activation occurs in parallel. However,observers often fail to report both targets because tokenization proceeds serially:While 1 target is being tokenized, the other’s trace may decay below the activationlevel necessary for tokenization.

scholarly journals Wide Field Imaging and Angiography

2017 ◽  
pp. 32-37
Keyword(s):  
Age Related Macular Degeneration ◽  
Peripheral Retina ◽  
Management Approach ◽  
Wide Field ◽  
Autofluorescence Imaging ◽  
Retinal Periphery ◽  
Age Related ◽  
Increased Risk ◽  
Field Imaging ◽  
Wide Field Imaging

The recently developed wide-field imaging systems (WIS) enable 200 degrees imaging of retina by just one shot and angiographic and autofluorescence imaging of retinal periphery. In addition to facilitating the detection of retinal pathologies, WIS revealed the importance of lesions in retinal periphery and peripheral nonperfusion areas invisible by standard angiography. The novel finding of utmost importance for diabetic retinopathy (DR) patients was the 3 fold increased risk of progression assessed for peripheral DR lesions compared to that in the posterior pole. Detection of peripheral nonperfusion areas in DR or retinal vein occlusion cases with refractory macular edema altered the management approach. On the other hand by means of WIS new terms have been brought into the era like peripheral vascular leakage whose relevance and importance are unknown for retinal vascular diseases. In age-related macular degeneration, a disease known to affect the macula, WIS proved the effect on peripheral retina documented by both angiographies and also peripheral autofluorescence. In diseases known to affect peripheral retina like uveitis, degenerative myopia, etc. WIS further contributes to the detection of additional pathologies. WIS enabled documentation of retinal periphery and thus seems to change the treatment modality and probably clinical classification of unknown or treatment-refractory pathologies in retinal diseases where we mainly focused on macula always.

scholarly journals Retinal Periphery Is Insensitive to Sudden Transient Motion

i-Perception ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 204166952093702
Author(s):  
Stuart Anstis
Keyword(s):  
Transient Motion ◽  
Retinal Periphery ◽  
Dynamic Noise ◽  
The Right

Peripherally viewed targets moved around against a background of random dynamic noise. Slow movements were visible, fast movements were not. Thus, a target that repetitively drifted to the right and snapped back appeared to drift endlessly to the right with no visible snapbacks.

Primary Modality for Speech Perception in Children with Normal and Impaired Hearing

1985 ◽  
Vol 28 (1) ◽  
pp. 36-46 ◽  
Author(s):  
Richard C. Seewald ◽  
Mark Ross ◽  
Thomas G. Giolas ◽  
A. Yonovitz
Keyword(s):  
Word Identification ◽  
Visual Presentation ◽  
Predictor Variables ◽  
Hearing Level ◽  
Impaired Hearing ◽  
Monosyllabic Word ◽  
Speech Reception ◽  
Auditory Word ◽  
Conflict Condition ◽  
Impaired Children

The relationships between each of seven predictor variables and the relative degree to which 84 normal and hearing-impaired children used audition or vision in their perception of word stimuli were investigated. The children's relative use of audition or vision was assessed by the auditory-visual presentation of monosyllabic word stimuli in which the visual word stimuli were in conflict with those presented acoustically. Six of the seven predictor variables were significantly correlated with the performance scores obtained within the auditory-visual conflict condition. Only pure-tone average hearing level and auditory word identification performance, however, made unique contributions toward predicting the degree to which audition or vision was used in the perception of the word stimuli. We concluded that the relative use of audition or vision was almost completely related to their auditory capabilities as represented by the children's unaided threshold sensitivity and aided speech reception performance.

Retinal vasoproliferative tumour secondary to retinitis pigmentosa sine pigmento

2021 ◽  
Vol 14 (5) ◽  
pp. e240878
Author(s):  
Albert John Bromeo ◽  
Sweet Jorlene Lerit ◽  
Amadeo Veloso ◽  
Gary John Mercado
Keyword(s):  
Retinal Detachment ◽  
Retinitis Pigmentosa ◽  
Laser Photocoagulation ◽  
Vision Loss ◽  
Peripheral Retina ◽  
Focal Laser Photocoagulation ◽  
Feeder Vessel ◽  
Eye Examination ◽  
The Right

Retinitis pigmentosa can be associated with exudative vasculopathy in rare instances, which can manifest as retinal vasoproliferative tumours. We present the case of a 33-year-old woman previously diagnosed with retinitis pigmentosa sine pigmentosa in both eyes. She was asymptomatic and just came in for a routine follow-up eye examination. Thorough examination of the peripheral retina on the right eye revealed a dome-shaped retinal tumour with a feeder vessel and surrounding exudative changes at the superotemporal periphery, consistent with a secondary retinal vasoproliferative tumour from retinitis pigmentosa. She subsequently underwent focal laser photocoagulation of the tumour which resulted in tumour stabilisation. While exudative vasculopathy is very uncommon in retinitis pigmentosa, ophthalmologists need to be aware of its occurrence in such patients. Vision loss may occur from exudation, haemorrhage, retinal detachment and neovascularisation. A thorough examination of the peripheral retina is warranted in these cases.

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