Visually Perceived Eye Level is Influenced Identically by Lines from Erect and Pitched Planes

The physical elevation that appears to correspond to eye level (VPEL), as measured with a small visual target, changes systematically with the orientation in depth (‘visual pitch’) of a visual field consisting of one or two pitched-from-vertical lines in darkness. The influence is large and, with a one-line stimulus, is only 15% smaller than the influence exerted by a complexly structured, well-illuminated, pitched visual field. A line from a frontoparallel plane can be presented to the same retinal locus as a pitched-from-vertical line; the three experiments in the present report were aimed at determining the influence on VPEL from such lines. In the first two experiments the subject viewed a visual field consisting of a one-line or two-line pitched-from-vertical stimulus from a pitched-only plane or an oblique one-line or two-line stimulus from an erect plane. Each of the pitched-from-vertical stimuli was presented at seven different orientations separated by 10° over a ±30° range. Each of the oblique-line stimuli was presented at an orientation that resulted in stimulation to the same retinal locus as one of the conditions with pitched-from-vertical lines, and thus a range of ‘equivalent pitches’ was examined that corresponded to the range of pitches for the pitched-from-vertical lines. The variation in orientation of the oblique-line stimulus and the pitched-from-vertical stimulus each produced systematic changes in VPEL; the two were indistinguishable. A third experiment specifically designed to examine the possibility that either stimulus sequencing or lack of naivity of the subjects might have been involved turned up no such effects. It is concluded that the aspect of a line stimulus that controls the influence on VPEL is the orientation of the image of the line on a projection sphere centered on the nodal point of the eye or, as in the present experiments with viewing in primary position, the retinal locus stimulated; the orientation-in-depth of the stimulating line provides no additional influence on VPEL for the stationary, erect, monocularly viewing observer. The results are interpreted within the framework of the great-circle model.

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Conscious access to fear-relevant information is mediated by threshold

Polish Psychological Bulletin ◽

10.2478/v10059-011-0009-7 ◽

2011 ◽

Vol 42 (2) ◽

pp. 56-64 ◽

Cited By ~ 2

Author(s):

Remigiusz Szczepanowski

Keyword(s):

Present Report ◽

Intrinsic Property ◽

Roc Curves ◽

Relevant Information ◽

Perceptual Processing ◽

High Threshold ◽

Operating Characteristics ◽

Emotional Perception ◽

Fearful Faces ◽

The Subject

Conscious access to fear-relevant information is mediated by thresholdThe present report proposed a model of access consciousness to fear-relevant information according to which there is a threshold for emotional perception beyond that the subject makes hits with no false alarm. The model was examined by having the participants performed a confidence-ratings masking task with fearful faces. Measures of the thresholds for conscious access were taken by looking at the receiver operating characteristics (ROC) curves generated from a three-state low- and high-threshold (3-LHT) model by Krantz. Indeed, the analysis of the masking data revealed that the ROCs had threshold-like-nature (a two-limb shape) rather continuous (a curvilinear shape) challenging in this fashion the classical signal-detection view on perceptual processing. Moreover, the threshold ROC curve exhibited the specific y-intercepts relevant to conscious access performance. The study suggests that the threshold can be an intrinsic property of conscious access, mediating emotional contents between perceptual states and consciousness.

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Computerized color perimetry in multiple sclerosis

Multiple Sclerosis Journal ◽

10.1177/135245859800400207 ◽

1998 ◽

Vol 4 (2) ◽

pp. 79-84 ◽

Cited By ~ 6

Author(s):

N Accornero ◽

S Rinalduzzi ◽

M Capozza ◽

E Millefiorini ◽

G C Filligoi ◽

...

Keyword(s):

Visual Field ◽

Statistical Difference ◽

Cost Effective ◽

Quantitative Information ◽

Field Analysis ◽

Visual Field Defects ◽

Highly Sensitive ◽

The Subject ◽

Color Perimetry ◽

Field Defects

Color visual field analysis has proven highly sensitive for early visual impairments diagnosis in MS, yet it has never attained widespread popularity usually because the procedure is difficult to standardize, the devices are costly, and the test is fatiguing. We propose a computerized procedure running on standard PC, cost effective, clonable, and easy handled. Two hundred and sixty-four colored patches subtending 18 angle of vision, with selected hues and low saturation levels are sequentially and randomly displayed on gray equiluminous background of the PC screen subtending 2486408 angle of vision. The subject is requested to press a switch at the perception of the stimulus. The output provides colored maps with quantitative information. Comparison between normals and a selected population of MS patients with no actual luminance visual field defects, showed high statistical difference.

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NUMERICAL SIMULATION OF TSUNAMIS ORIGINATING IN THE PERU-CHILE TRENCH

Coastal Engineering Proceedings ◽

10.9753/icce.v15.60 ◽

1976 ◽

Vol 1 (15) ◽

pp. 60

Author(s):

A.W. Garcia ◽

H.L. Butler

Keyword(s):

Present Report ◽

Development Program ◽

Numerical Code ◽

Army Corps ◽

Army Corps Of Engineers ◽

The Pacific ◽

The Subject ◽

Chile Tsunami ◽

Tsunami Amplitude

The U. S. Army Corps of Engineers has as an objective of its research and development program the determination of better harbor design criteria for tsunami protection. A previous report (Houston, et. al., 1975b) addressed the subject of tsunami vulnerability of the Pacific Coast of the continental United States to tsunamis originating in the Aleutian Trench. That report determined the variation in tsunami amplitude as a function of coastal distance due to a standard uplift source at different locations in the Aleutian Trench. The present report is a continuation of that study and addresses the subject of tsunami vulnerability along the same stretch of coast to tsunamis originating in the Peru-Chile Trench. In addition, modifications to the numerical code used in the previous report allowed the simulation of the Chile tsunami of May 22, 1960.

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Comparison at a Distance

Perception ◽

10.1068/p3393 ◽

2003 ◽

Vol 32 (4) ◽

pp. 395-414 ◽

Cited By ~ 14

Author(s):

Marina V Danilova ◽

John D Mollon

Keyword(s):

Visual Field ◽

Spatial Frequency ◽

Visual System ◽

Spatial Separation ◽

Orientation Discrimination ◽

Human Observer ◽

Systematic Effect ◽

Trained Subjects ◽

Stimulus Attribute ◽

The Subject

The visual system is known to contain hard-wired mechanisms that compare the values of a given stimulus attribute at adjacent positions in the visual field; but how are comparisons performed when the stimuli are not adjacent? We ask empirically how well a human observer can compare two stimuli that are separated in the visual field. For the stimulus attributes of spatial frequency, contrast, and orientation, we have measured discrimination thresholds as a function of the spatial separation of the discriminanda. The three attributes were studied in separate experiments, but in all cases the target stimuli were briefly presented Gabor patches. The Gabor patches lay on an imaginary circle, which was centred on the fixation point and had a radius of 5 deg of visual angle. Our psychophysical procedures were designed to ensure that the subject actively compared the two stimuli on each presentation, rather than referring just one stimulus to a stored template or criterion. For the cases of spatial frequency and contrast, there was no systematic effect of spatial separation up to 10 deg. We conclude that the subject's judgment does not depend on discontinuity detectors in the early visual system but on more central codes that represent the two stimuli individually. In the case of orientation discrimination, two naïve subjects performed as in the cases of spatial frequency and contrast; but two highly trained subjects showed a systematic increase of threshold with spatial separation, suggesting that they were exploiting a distal mechanism designed to detect the parallelism or non-parallelism of contours.

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Can positions in the visual field with high attentional capabilities be good candidates for a new preferred retinal locus?

Vision Research ◽

10.1016/j.visres.2017.07.009 ◽

2017 ◽

Vol 140 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Maria J. Barraza-Bernal ◽

Iliya V. Ivanov ◽

Svenja Nill ◽

Katharina Rifai ◽

Susanne Trauzettel-Klosinski ◽

...

Keyword(s):

Visual Field ◽

Retinal Locus

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Human rather than ape-like orbital morphology allows much greater lateral visual field expansion with eye abduction

Scientific Reports ◽

10.1038/srep12437 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 4

Author(s):

Eric Denion ◽

Martin Hitier ◽

Eric Levieil ◽

Frédéric Mouriaux

Keyword(s):

Computed Tomography ◽

Mathematical Model ◽

Visual Field ◽

Sagittal Plane ◽

Primary Position ◽

Orbital Margin ◽

Eye Motion ◽

Human Skulls ◽

The Mathematical Model ◽

Tomography Data

Abstract While convergent, the human orbit differs from that of non-human apes in that its lateral orbital margin is significantly more rearward. This rearward position does not obstruct the additional visual field gained through eye motion. This additional visual field is therefore considered to be wider in humans than in non-human apes. A mathematical model was designed to quantify this difference. The mathematical model is based on published computed tomography data in the human neuro-ocular plane (NOP) and on additional anatomical data from 100 human skulls and 120 non-human ape skulls (30 gibbons; 30 chimpanzees / bonobos; 30 orangutans; 30 gorillas). It is used to calculate temporal visual field eccentricity values in the NOP first in the primary position of gaze then for any eyeball rotation value in abduction up to 45° and any lateral orbital margin position between 85° and 115° relative to the sagittal plane. By varying the lateral orbital margin position, the human orbit can be made “non-human ape-like”. In the Pan-like orbit, the orbital margin position (98.7°) was closest to the human orbit (107.1°). This modest 8.4° difference resulted in a large 21.1° difference in maximum lateral visual field eccentricity with eyeball abduction (Pan-like: 115°; human: 136.1°).

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1.17. Bulge and bar: a possible way of their formation

Symposium - International Astronomical Union ◽

10.1017/s0074180900083960 ◽

1998 ◽

Vol 184 ◽

pp. 49-50

Author(s):

S.N. Nuritdinov ◽

E.R. Gaynullia ◽

K.T. Mirtodjieva

Keyword(s):

Observational Data ◽

Stability Problem ◽

Initial Conditions ◽

Present Report ◽

Spherical Collapse ◽

The Subject ◽

The Law ◽

The Stability ◽

Gravitating Systems

Some observational data indicate that galaxy subsystems, including their central areas, first of all are the result of their global nonstationary evolution. That is why we earlier built (Nuritdinov 1992) the exact non-linearly pulsing rotating models of disklike and spherical self-gravitating systems. Unlike other authors we want to research the stability problem of nonlinear nonstationary models. In the present report we want to give only those results of the instability studied, which have a direct attitude to the subject under discussion. We put a certain question: what initial conditions have to exist, for instance, for the value of the virial parameter (2T/|U|)0 and the parameter of anisotropy < Tr > / < T⊥ >, that the collapse of a disk should result in a bar, and the spherical collapse will result in a thick ellipsoidal bulge. To answer the question it is very important to study stability of the solvable nonlinear unequilibrium models. All models discussed below pulsate under the law R = II(ψ)R0, where (Nuritdinov 1985)

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Cephalosporins’ Cross-Reactivity and the High Degree of Required Knowledge. Case Report and Review of the Literature

Antibiotics ◽

10.3390/antibiotics9050209 ◽

2020 ◽

Vol 9 (5) ◽

pp. 209

Author(s):

Stefano D’Errico ◽

Paola Frati ◽

Martina Zanon ◽

Eleonora Valentinuz ◽

Federico Manetti ◽

...

Keyword(s):

Present Report ◽

Specific Ige ◽

Chain Structure ◽

Cross Reactivity ◽

Side Chain ◽

Mast Cell Tryptase ◽

Immunohistochemical Examination ◽

Femoral Blood ◽

The Subject ◽

High Degree

Antibiotic cross-reactivity represents a phenomenon of considerable interest as well as antibiotic resistance. Immediate reactions to cephalosporins are reported in the literature with a prevalence of only 1–3% of the population, while anaphylactic reactions are rarely described (approximately 0.0001–0.1%) as well as fatalities. Allergic reaction to cephalosporins may occur because of sensitization to unique cephalosporin haptens or to determinants shared with penicillins. Cross-reactivity between cephalosporins represents, in fact, a well-known threatening event involving cephalosporins with similar or identical R1- or R2-side chains. The present report describes the case of a 79-year-old man who suddenly died after intramuscular administration of ceftriaxone. Serum dosage of mast cell tryptase from a femoral blood sample at 3 and 24 h detected values of 87.7μg/L and 93.5μg/L, respectively (cut-off value 44.3 μg/L); the serum-specific IgE for penicillins, amoxicillin, cephaclor and also for the most common allergens were also determined. A complete post-mortem examination was performed, including gross, histological and immunohistochemical examination, with an anti-tryptase antibody. The cause of death was identified as anaphylactic shock: past administrations of cefepime sensitized the subject to cephalosporins and a fatal cross-reactivity of ceftriaxone with cefepime occurred due to the identical seven-position side chain structure in both molecules. The reported case offers food for thought regarding the study of cross-reactivity and the need to clarify the predictability and preventability of the phenomenon in fatal events.

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‘Skin Portraiture’ in the Age of Bio Art

Body & Society ◽

10.1177/1357034x18766288 ◽

2018 ◽

Vol 24 (1-2) ◽

pp. 137-165 ◽

Cited By ~ 2

Author(s):

Heidi Kellett

Keyword(s):

Visual Field ◽

Arts And Humanities ◽

The Arts ◽

Embodied Experiences ◽

The Subject

In this article, I consider ‘skin portraiture’: a mode of representation that privileges quasi-anonymous, fragmented, magnified and anatomized images of skin. I argue that this mode of representation permits a heightened awareness of embodied experiences such as reflexivity, empathy and relationality. Expanding understandings of difference through its engagement with haptic imagery and visuality, skin portraiture reorients the boundaries between ‘I’/‘not I’ and subject/object – often through touch – and challenges the cultural commitment to traditional notions of bodily autonomy. By doing so, skin portraiture functions as an antagonistic form of portraiture; that is, as a kind of anti-portraiture that pushes the genre into an expanded visual field and, at times, beyond representation. Exploring the skin-as-technology metaphor, I show that bio art skin portraiture creates chimeric skins through tissue culturing practices, permitting bodies to become radically relational. Bio art skin portraits celebrate the genetic and cellular differences between bodies through a visible collapse of epidermal boundaries, which engenders a hyper-haptic mode of seeing beyond the subject and her or his skin. Analysing the bio art of Jalia Essaïdi, ORLAN and Julia Reodica, and drawing on the work of Laura Marks and Erin Manning, this article explores the skin-as-technology metaphor in order to offer the arts and humanities an innovative understanding of contemporary embodiment.

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