Serial Checking of Letter Targets

1981 ◽  
Vol 53 (1) ◽  
pp. 291-297 ◽  
Author(s):  
Tatsuo Tone
Keyword(s):  
Letter Array ◽  
Visual Difficulty

A total of 24 subjects quickly and correctly checked target Zs in a letter array in order of location. Zs were embedded in angular, round, and mixed angular and round nontarget letters. Checking rate decreased as visual difficulty increased but increased as the number of letters interposed between adjacent targets increased. Time per letter computed for a span, which included a target and interposed letters preceding the target, varied as a function of checking the order of targets. The trend of the variation in rate differentiated among spans of different length and was also influenced by the visual difficulty. This differentiation might represent subject's unintended strategy for the task.

scholarly journals The Global Burden of Visual Difficulty in Low, Middle, and High Income Countries

PLoS ONE ◽  
2013 ◽  
Vol 8 (5) ◽  
pp. e63315 ◽  
Author(s):  
Ellen E. Freeman ◽  
Marie-Hélène Roy-Gagnon ◽  
Elodie Samson ◽  
Slim Haddad ◽  
Marie-Josée Aubin ◽  
...  
Keyword(s):  
High Income ◽  
Global Burden ◽  
Visual Difficulty

Visual Difficulty Driving at Night

1983 ◽  
Vol 66 (1) ◽  
pp. 20-24 ◽  
Author(s):  
J. M. STEWARD ◽  
B.L. COLE ◽  
J.L. PETTIT
Keyword(s):  
Visual Difficulty

scholarly journals NUMERICAL ANALYSIS OF TUNNEL LED LIGHTING MAINTENANCE FACTOR

2018 ◽  
Vol 19 (2) ◽  
pp. 154-163 ◽  
Author(s):  
Mehmet Sait Cengiz ◽  
ÇIĞDEM CENGIZ
Keyword(s):  
Energy Efficiency ◽  
Numerical Analysis ◽  
Environmental Conditions ◽  
Luminous Flux ◽  
International Standards ◽  
Optical Losses ◽  
Led Lighting ◽  
Maintenance Factors ◽  
Visual Difficulty

ABSTRACT:  It is necessary to periodically maintain lighting equipment in accordance with international standards. Contamination of lamps caused by long-term use of lighting equipment will result in loss of Luminous Flux and optical losses. The decrease in lighting performance poses a visual difficulty for drivers and causes accidents. In this study, the total Maintenance Factor is numerically examined by considering the losses of diffuser and lens for LED lamps used in tunnel lighting. The variation of luminaries performance with years considering Maintenance Factors as regards environmental conditions and features of the luminaries is evaluated to demonstrate the importance of tunnel lighting maintenance. Moreover, to show the importance of LED lamps Maintenance Factor, the variation of illumination levels of LED lamps is analysed under different Maintenance Factors. It is observed that enhancing Maintenance Factor would contribute to energy efficiency. ABSTRAK: Penjagaan peralatan cahaya secara berkala mengikut piawai kebangsaan adalah amat penting. Pencemaran lampu disebabkan penggunaan peralatan cahaya pada jangka panjang akan menyebabkan kehilangan kilauan kerdipan lampu dan optik. Pengurangan pencahayaan ini menyebabkan kesukaran pandangan pada pemandu dan menyebabkan kemalangan jiwa. Kajian ini mengkaji tentang jumlah Faktor Penjagaan secara numerik dengan mengambil kira pengurangan difuser dan kanta pada lampu LED yang digunakan dalam terowong pencahayaan. Faktor Penjagaan pada perubahan kilauan berdasarkan tahun mengambil kira keadaan sekeliling dan ciri khas kilauan. Tambahan, ini dinilai bagi menunjukkan kepentingan penjagaan terowong pencahayaan dan kepentingan Faktor Penjagaan Lampu LED. Perubahan pada tahap terang pada lampu LED dikaji dengan mengambil kira Faktor Penjagaan. Peningkatan pada Faktor Penjagaan telah didapati dapat menjimatkan tenaga.

SportsCenter: A Case Study of Media Framing U.S. Sport as the COVID-19 Epicenter

2020 ◽  
pp. 1-20
Author(s):  
Travis R. Bell
Keyword(s):  
National Collegiate Athletic Association ◽  
Professional Sports ◽  
Media Framing ◽  
Breaking News ◽  
Men's Basketball ◽  
Global Context ◽  
Sports Leagues ◽  
American Society ◽  
Visual Difficulty

When COVID-19 enveloped sport, it presented SportsCenter, ESPN’s primary news vehicle, with an unexpected and ironic form of “March Madness,” with basketball as the sporting epicenter for a pandemic. This case study applied an ethnographic content analysis to examine how the cancellation or postponement of sport as a result of COVID-19 was framed across 22 episodes of SportsCenter from March 8 to 14, 2020. More than 134 min of coverage was devoted to COVID-19-related stories, and 268 unique types of stories were produced. Descriptive statistics suggested that COVID-19 was framed as having a direct impact on U.S. men’s professional sports leagues and the National Collegiate Athletic Association men’s basketball tournament. When considering news format characteristics, SportsCenter produced its coverage through convenience and relevance to ESPN, not sport. Even during a “breaking news” pandemic, SportsCenter retained its long-standing news process of gender bias and nationalistic favoritism. The visual difficulty of how to “show” coronavirus also presented a production challenge, but the messages and cues embedded in the visuals depicted a rapid shift in discourse that focused on basic reporting without health or global context. Instead, SportsCenter overwhelmed viewers with how sport was ripped away from (U.S.) American society.

scholarly journals Specificity of the Effect of a Nicotinic Receptor Polymorphism on Individual Differences in Visuospatial Attention

2005 ◽  
Vol 17 (10) ◽  
pp. 1611-1620 ◽  
Author(s):  
Pamela M. Greenwood ◽  
John A. Fossella ◽  
Raja Parasuraman
Keyword(s):  
Individual Differences ◽  
Nicotinic Receptor ◽  
Receptor Gene ◽  
Visuospatial Attention ◽  
Normal Variation ◽  
Domain Specific ◽  
Specific Effects ◽  
Dopamine Beta Hydroxylase ◽  
Letter Array ◽  
Search Speed

Cortical neurotransmitter availability is known to exert domain-specific effects on cognitive performance. Hence, normal variation in genes with a role in neurotransmission may also have specific effects on cognition. We tested this hypothesis by examining associations between polymorphisms in genes affecting cholinergic and noradrenergic neurotransmission and individual differences in visuospatial attention. Healthy individuals were administered a cued visual search task which varied the size of precues to the location of a target letter embedded in a 15-letter array. Cues encompassed 1, 3, 9, or 15 letters. Search speed increased linearly with precue size, indicative of a spatial attentional scaling mechanism. The strength of attentional scaling increased progressively with the number of C alleles (0, 1, or 2) of the alpha-4 nicotinic receptor gene C1545T polymorphism (n = 104). No association was found for the dopamine beta hydroxylase gene G444A polymorphism (n = 135). These findings point to the specificity of genetic neuromodulation. Whereas variation in a gene linked to cholinergic transmission systematically modulated the ability to scale the focus of visuospatial attention, variation in a gene governing dopamine availability did not. The results show that normal variation in a gene controlling a nicotinic receptor makes a selective contribution to individual differences in visuospatial attention.

Word Length and Visual-Noise Texture in Backward Masking

Perception ◽  
1976 ◽  
Vol 5 (2) ◽  
pp. 211-215 ◽  
Author(s):  
Harold S Zamansky ◽  
Thomas R Corwin
Keyword(s):  
Present Experiment ◽  
Visual Angle ◽  
Word Length ◽  
Visual Noise ◽  
Backward Masking ◽  
Stroke Width ◽  
Letter Array ◽  
Feature Similarity ◽  
The One

Visual-noise masks composed of randomly scattered letter fragments disrupt the recognition of briefly viewed letter arrays when the masks are presented immediately after these arrays. According to the feature-similarity assumption, maximal disruption should occur when the target letters and the letter fragments comprising the mask share a common stroke width. This assumption was disconfirmed in the present experiment. Two-, four-, and six-letter arrays, whose stroke width subtended a visual angle of 3·8′, were viewed tachistoscopically in conjunction with visual-noise masks whose letter fragments subtended visual angles of 1·2′, 1·9′, 3·8′, 6·6′, or 9·7′. The most effective mask for all three letter-array lengths was the one composed of letter fragments subtending 6·6′. The results, together with those of previous experiments, are accounted for in terms of a neural line-detecting mechanism.

On the Construction and Maintenance of Expectancies

1978 ◽  
Vol 30 (3) ◽  
pp. 441-454 ◽  
Author(s):  
John P. McLean ◽  
Gordon L. Shulman
Keyword(s):  
Reaction Time ◽  
Attention Allocation ◽  
Matching Task ◽  
Distractor Task ◽  
Probe Task ◽  
Letter Array ◽  
Matching Cost ◽  
Delay Cost ◽  
Memory Activation

Reaction time techniques were used to examine the role of attention in the construction and maintenance of expectancies. In Experiment I, a primed letter matching task, expectancies were observed through a delay (cost) in responding to misprimed letter arrays. A secondary probe task was interpolated between prime and array letters on some of the trials, with attentional demands inferred from delayed responding to probes. By varying the amount of time between onset of the prime and either a probe or letter array, it was found that there is attentional involvement (as reflected in probe inhibition) prior to the observation of expectancies (as reflected in letter matching cost). It was also found that the interpolation of an attention-demanding probe task did not entirely disrupt primed expectancies. Experiment II found that an expectancy persists even when an interpolated distractor task signals that the expectancy is no longer valid. These expectancies were found to decay as a function of time. The implications of these results for attention allocation and memory activation views of expectancy were discussed.

Including Students with Visual Difficulty within Higher Education: Necessary Steps

2017 ◽  
Vol 26 (4) ◽  
pp. 266-282 ◽  
Author(s):  
Halis Sakız ◽  
Mehmet Sarıcalı
Keyword(s):  
Higher Education ◽  
Visual Difficulty

Visual Sensitivity Shifts with Perceived Eye Position

2013 ◽  
Vol 25 (7) ◽  
pp. 1180-1189 ◽  
Author(s):  
Bartholomäus Odoj ◽  
Daniela Balslev
Keyword(s):  
Visuospatial Attention ◽  
Visual Sensitivity ◽  
Functional Coupling ◽  
Eye Position ◽  
Lateral Eye ◽  
Position Signal ◽  
Letter Array ◽  
Eye Rotation ◽  
Sound Experiment ◽  
Selection Of

Spatial attention can be defined as the selection of a location for privileged stimulus processing. Most oculomotor structures, such as the superior colliculus or the FEFs, play an additional role in visuospatial attention. Indeed, electrical stimulation of these structures can cause changes in visual sensitivity that are location specific. We have proposed that the recently discovered ocular proprioceptive area in the human postcentral gyrus (S1EYE) may have a similar function. This suggestion was based on the observation that a reduction of excitability in this area with TMS causes not only a shift in perceived eye position but also lateralized changes in visual sensitivity. Here we investigated whether these shifts in perceived gaze position and visual sensitivity are spatially congruent. After continuous theta burst stimulation over S1EYE, participants underestimated own eye rotation, so that saccades from a lateral eye rotation undershoot a central sound (Experiment 1). They discriminated letters faster if they were presented nearer the orbit midline (Experiment 2) and spent less time looking at locations nearer the orbit midline when searching for a nonexistent target in a letter array (Experiment 3). This suggests that visual sensitivity increased nearer the orbit midline, in the same direction as the shift in perceived eye position. This spatial congruence argues for a functional coupling between the cortical eye position signal in the somatosensory cortex and visuospatial attention.

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