Basic visual observation skills training course. Final report

International Nuclear Information System (INIS)

Toquam, J.L.; Morris, F.A.; Griggs, J.R.

1995-06-01

This is the third report in a series prepared to assist the International Atomic Energy Agency (IAEA or Agency) in enhancing the effectiveness of its international safeguards inspections through inspector training in Observation Skills. The first report (Phase 1) was essentially exploratory. It defined Observation Skills' broadly to include all appropriate cognitive, communications, and interpersonal techniques that have the potential to help IAEA safeguards inspectors function more effectively. The second report (Phase 2) provided a more specific basis for the actual design and delivery of Observation Skills training to IAEA inspectors. The present report (Phase 3) documents the design of a Basic Visual Observation Skills course and delivery of the course to safeguards inspectors at IAEA Headquarters Vienna in February and May of 1995. The purpose of the course is to help safeguards inspectors evaluate and improve their skills in making observations during inspections and in evaluating and interpreting this information. The course is basic in the sense that it provides training in skills which are generally applicable to inspections of all types of facilities and activities subject to safeguards. The course is designed for 16 hours of classroom delivery, ideally in four 4-hour sessions over a period of four days. The first 12 hours provide training in five skill areas: perception and recognition; attention and attention to detail; memory; mental imaging, mapping, and modeling skills; and judgment and decision making. Following the training in each of the five skill areas is an Integrating Exercise involving a simulated safeguards inspection

An Ideal Observer Analysis of Visual Working Memory

Science.gov (United States)

Sims, Chris R.; Jacobs, Robert A.; Knill, David C.

2012-01-01

Limits in visual working memory (VWM) strongly constrain human performance across many tasks. However, the nature of these limits is not well understood. In this article we develop an ideal observer analysis of human VWM by deriving the expected behavior of an optimally performing but limited-capacity memory system. This analysis is framed around…

Accuracy of visual wave observation from merchant ships and estimated wave loads; Accuracy of visual wave observation from merchant ships and estimated wave loads

Energy Technology Data Exchange (ETDEWEB)

Kawabe, H. [National Defense Academy, Kanagawa (Japan); Masaoka, K. [University of Osaka Prefecture, Osaka (Japan). Faculty of Engineering

1998-06-01

There is a large number of studies on discussions concerning accuracy of visual observation of waves and the correction method thereon. This paper give considerations on observation accuracy placing a viewpoint on that by merchant ships. Based on ship meteorological observation tables reported to the Meteorological Agency of Japan on meteorology in North Pacific during 14 years from 1976 to1989, wave observation values taken by merchant ships and observation ships were compared statistically to investigate the accuracy of visual wave observations carried out by merchant ships. With regard to wave heights, the observation values taken by the observation ships and the merchant ships have strong correlation, where the merchant ships evaluate them somewhat higher than the observation ships. Regarding wave cycles of wind waves, the merchant ships tend to have the observation values on longer cycle side. Correlation between the observations values by the merchant ships and the observation ships is weak both in wind waves and swells. There is not much of variation in accuracy of observations during daytime and at night performed by the merchant ships. It will be necessary in the future to give considerations on a method to correct the observation values on wave cycles taken by the merchant ship, and on a correction method in which both of the wave cycles and the wave heights are corrected simultaneously to make the observation values of the merchant ship equal to those of the observation ships. Thus, the observation values reported by general merchant ships in a large number every year will have to be utilized more effectively. 11 refs., 21 figs., 2 tabs.

Utilizing visual art to enhance the clinical observation skills of medical students.

Science.gov (United States)

Jasani, Sona K; Saks, Norma S

2013-07-01

Clinical observation is fundamental in practicing medicine, but these skills are rarely taught. Currently no evidence-based exercises/courses exist for medical student training in observation skills. The goal was to develop and teach a visual arts-based exercise for medical students, and to evaluate its usefulness in enhancing observation skills in clinical diagnosis. A pre- and posttest and evaluation survey were developed for a three-hour exercise presented to medical students just before starting clerkships. Students were provided with questions to guide discussion of both representational and non-representational works of art. Quantitative analysis revealed that the mean number of observations between pre- and posttests was not significantly different (n=70: 8.63 vs. 9.13, p=0.22). Qualitative analysis of written responses identified four themes: (1) use of subjective terminology, (2) scope of interpretations, (3) speculative thinking, and (4) use of visual analogies. Evaluative comments indicated that students felt the exercise enhanced both mindfulness and skills. Using visual art images with guided questions can train medical students in observation skills. This exercise can be replicated without specially trained personnel or art museum partnerships.

Sea-ice monitoring by ship-based visual observation during JARE ―Simplification of observation method based on the ASPeCt protocol―

OpenAIRE

Kay I. Ohshima; Shuki Ushio; Akihisa S. Otsuki

2006-01-01

A protocol for ship-based visual observation of sea ice is proposed for the Japanese Antarctic Research Expedition (JARE). The protocol is a simplified version of the ASPeCt protocol, used for extracting quantitative information on sea ice. The ship-based visual observations started from JARE-46. In the pack ice region, ice thickness, ratio of deformed ice, and total ice volume increased toward the coast. Continuous monitoring of sea ice, particularly its thickness, by ship-based observation ...

Genetic parameter estimates for carcass traits and visual scores including or not genomic information.

Science.gov (United States)

Gordo, D G M; Espigolan, R; Tonussi, R L; Júnior, G A F; Bresolin, T; Magalhães, A F Braga; Feitosa, F L; Baldi, F; Carvalheiro, R; Tonhati, H; de Oliveira, H N; Chardulo, L A L; de Albuquerque, L G

2016-05-01

The objective of this study was to determine whether visual scores used as selection criteria in Nellore breeding programs are effective indicators of carcass traits measured after slaughter. Additionally, this study evaluated the effect of different structures of the relationship matrix ( and ) on the estimation of genetic parameters and on the prediction accuracy of breeding values. There were 13,524 animals for visual scores of conformation (CS), finishing precocity (FP), and muscling (MS) and 1,753, 1,747, and 1,564 for LM area (LMA), backfat thickness (BF), and HCW, respectively. Of these, 1,566 animals were genotyped using a high-density panel containing 777,962 SNP. Six analyses were performed using multitrait animal models, each including the 3 visual scores and 1 carcass trait. For the visual scores, the model included direct additive genetic and residual random effects and the fixed effects of contemporary group (defined by year of birth, management group at yearling, and farm) and the linear effect of age of animal at yearling. The same model was used for the carcass traits, replacing the effect of age of animal at yearling with the linear effect of age of animal at slaughter. The variance and covariance components were estimated by the REML method in analyses using the numerator relationship matrix () or combining the genomic and the numerator relationship matrices (). The heritability estimates for the visual scores obtained with the 2 methods were similar and of moderate magnitude (0.23-0.34), indicating that these traits should response to direct selection. The heritabilities for LMA, BF, and HCW were 0.13, 0.07, and 0.17, respectively, using matrix and 0.29, 0.16, and 0.23, respectively, using matrix . The genetic correlations between the visual scores and carcass traits were positive, and higher correlations were generally obtained when matrix was used. Considering the difficulties and cost of measuring carcass traits postmortem, visual scores of

Neuroanatomy of the male pelvis in respect to radical prostatectomy including three-dimensional visualization.

Science.gov (United States)

Schwalenberg, Thilo; Neuhaus, Jochen; Liatsikos, Evangelos; Winkler, Mathias; Löffler, Sabine; Stolzenburg, Jens-Uwe

2010-01-01

The neuroanatomical structures of the radical prostatectomy (RP) are extensively discussed for their existence, localization and function. Especially structures, e.g. the so-called neurovascular bundle (NVB) that are points of debate in numerous anatomical studies. We review the literature and present our observations in cadaveric specimens, to reconstruct neuroanatomical structures in three dimensions (3D) with the use of appropriate computer applications and produce images of operative fields. We used an internet PubMed survey (http://www.ncbi.nlm.nih.gov) to review recent publications and included back copies of historical neuroanatomical studies from our own library. Our own experimental cadaveric (specimens preserved in Thiel's solution) studies of the autonomic nerve supply of the lower urinary tract were also reviewed. Visualization of the pelvic anatomy and neuroanatomy was done using computer-based software packages. No unified terminology for the structures of the NVBs can be presented to date. The innervation of the smooth muscular structures of the urethra and the complex morphology of urethral sphincter remain unclear. Our cadaveric studies showed that nerves are located on the lateral aspect of the prostate in addition to the NVBs described at the dorsolateral side of the prostate. The neuroanatomical investigations of the male pelvis and visualization of the structures in 3D enable the presentation of operative sites as seen intraoperatively. Moreover, dynamic depiction of the pelvic floor is also possible.

Development of a Graphical User Interface to Visualize Surface Observations

Energy Technology Data Exchange (ETDEWEB)

Buckley, R.L.

1998-07-13

Thousands of worldwide observing stations provide meteorological information near the earth's surface as often as once each hour. This surface data may be plotted on geographical maps to provide the meteorologist useful information regarding weather patterns for a region of interest. This report describes the components and applications of a graphical user interface which have been developed to visualize surface observations at any global location and time of interest.

Caroline Furness and the Evolution of Visual Variable Star Observing

Science.gov (United States)

Larsen, Kristine

2017-01-01

An Introduction to the Study of Variable Stars by Dr. Caroline Ellen Furness (1869-1936), Director of the Vassar College Observatory, was published in October 2015. Issued in honor of the fiftieth anniversary of the founding of Vassar College, the work was meant to fill a void in the literature, namely as both an introduction to the topic of variable stars as well as a manual explaining how they should be observed and the resulting data analyzed. It was judged to be one of the hundred best books written by an American woman in the last hundred years at the 1933 World’s Fair in Chicago. The book covers the relevant history of and background on types of variable stars, star charts, catalogs, and the magnitude scale, then describes observing techniques, including visual, photographic, and photoelectric photometry. The work finishes with a discussion of light curves and patterns of variability, with a special emphasis on eclipsing binaries and long period variables. Furness’s work is therefore a valuable snapshot of the state of astronomical knowledge, technology, and observing techniques from a century ago. Furness’s book and its reception in the scientific community are analyzed, and parallels with (and departures from) the current advice given by the AAVSO to beginning variable star observers today are highlighted.

Visual astronomy under dark skies a new approach to observing deep space

CERN Document Server

Cooke, Antony

2005-01-01

Modern astronomical telescopes, along with other advances in technology, have brought the deep sky - star clusters, nebulae and the galaxies - within reach of amateur astronomers. And it isn't even necessary to image many of these deep-sky objects in order to see them; they are within reach of visual observers using modern techniques and enhancement technology. The first requirement is truly dark skies; if you are observing from a light-polluted environment you need Tony Cooke's book, Visual Astronomy in the Suburbs. Given a site with clear, dark night skies everything else follows… this book will provide the reader with everything he needs to know about what to observe, and using some of today's state-of-the-art technique and commercial equipment, how to get superb views of faint and distant astronomical objects.

Spine surgeon's kinematics during discectomy, part II: operating table height and visualization methods, including microscope.

Science.gov (United States)

Park, Jeong Yoon; Kim, Kyung Hyun; Kuh, Sung Uk; Chin, Dong Kyu; Kim, Keun Su; Cho, Yong Eun

2014-05-01

Surgeon spine angle during surgery was studied ergonomically and the kinematics of the surgeon's spine was related with musculoskeletal fatigue and pain. Spine angles varied depending on operation table height and visualization method, and in a previous paper we showed that the use of a loupe and a table height at the midpoint between the umbilicus and the sternum are optimal for reducing musculoskeletal loading. However, no studies have previously included a microscope as a possible visualization method. The objective of this study is to assess differences in surgeon spine angles depending on operating table height and visualization method, including microscope. We enrolled 18 experienced spine surgeons for this study, who each performed a discectomy using a spine surgery simulator. Three different methods were used to visualize the surgical field (naked eye, loupe, microscope) and three different operating table heights (anterior superior iliac spine, umbilicus, the midpoint between the umbilicus and the sternum) were studied. Whole spine angles were compared for three different views during the discectomy simulation: midline, ipsilateral, and contralateral. A 16-camera optoelectronic motion analysis system was used, and 16 markers were placed from the head to the pelvis. Lumbar lordosis, thoracic kyphosis, cervical lordosis, and occipital angle were compared between the different operating table heights and visualization methods as well as a natural standing position. Whole spine angles differed significantly depending on visualization method. All parameters were closer to natural standing values when discectomy was performed with a microscope, and there were no differences between the naked eye and the loupe. Whole spine angles were also found to differ from the natural standing position depending on operating table height, and became closer to natural standing position values as the operating table height increased, independent of the visualization method

Improving visual observation skills through the arts to aid radiographic interpretation in veterinary practice: A pilot study.

Science.gov (United States)

Beck, Cathy; Gaunt, Heather; Chiavaroli, Neville

2017-09-01

Radiographic interpretation is a perceptual and cognitive skill. Recently core veterinary radiology textbooks have focused on the cognitive (i.e., the clinical aspects of radiographic interpretation) rather than the features of visual observation that improve identification of abnormalities. As a result, the skill of visual observation is underemphasized and thus often underdeveloped by trainees. The study of the arts in medical education has been used to train and improve visual observation and empathy. The use of the arts to improve visual observation skills in Veterinary Science has not been previously described. Objectives of this pilot study were to adapt the existing Visual Arts in Health Education Program for medical and dental students at the University of Melbourne, Australia to third year Doctor of Veterinary Medicine students and evaluate their perceptions regarding the program's effects on visual observation skills and confidence with respect to radiographic interpretation. This adaptation took the form of a single seminar given to third year Doctor of Veterinary Medicine students. Following the seminar, students reported an improved approach to radiographic interpretation and felt they had gained skills which would assist them throughout their career. In the year following the seminar, written reports of the students who attended the seminar were compared with reports from a matched cohort of students who did not attend the seminar. This demonstrated increased identification of abnormalities and greater description of the abnormalities identified. Findings indicated that explicit training in visual observation may be a valuable adjunct to the radiology training of Doctor of Veterinary Medicine students. © 2017 American College of Veterinary Radiology.

Basic visual observation skills training course: Appendix A. Final report

International Nuclear Information System (INIS)

Toquam, J.L.; Morris, F.A.; Griggs, J.R.

1995-06-01

The purpose of the basic visual observation skills course is to help safeguards inspectors evaluate and improve their skills in making observations during inspections and in evaluating and interpreting this information. The first 12 hours of the course provide training in five skill areas: perception and recognition; attention to detail; memory; mental imaging, mapping, and modeling skills; and judgment and decision making. Following this training is an integrating exercise involving a simulated safeguards inspection. This report contains the course manual and materials

Basic visual observation skills training course: Appendix A. Final report

Energy Technology Data Exchange (ETDEWEB)

Toquam, J.L.; Morris, F.A.; Griggs, J.R.

1995-06-01

The purpose of the basic visual observation skills course is to help safeguards inspectors evaluate and improve their skills in making observations during inspections and in evaluating and interpreting this information. The first 12 hours of the course provide training in five skill areas: perception and recognition; attention to detail; memory; mental imaging, mapping, and modeling skills; and judgment and decision making. Following this training is an integrating exercise involving a simulated safeguards inspection. This report contains the course manual and materials.

Deep Brain Stimulation of the Pedunculopontine Tegmental Nucleus (PPN Influences Visual Contrast Sensitivity in Human Observers.

Directory of Open Access Journals (Sweden)

Hendrik Strumpf

Full Text Available The parapontine nucleus of the thalamus (PPN is a neuromodulatory midbrain structure with widespread connectivity to cortical and subcortical motor structures, as well as the spinal cord. The PPN also projects to the thalamus, including visual relay nuclei like the LGN and the pulvinar. Moreover, there is intense connectivity with sensory structures of the tegmentum in particular with the superior colliculus (SC. Given the existence and abundance of projections to visual sensory structures, it is likely that activity in the PPN has some modulatory influence on visual sensory selection. Here we address this possibility by measuring the visual discrimination performance (luminance contrast thresholds in a group of patients with Parkinson's Disease (PD treated with deep-brain stimulation (DBS of the PPN to control gait and postural motor deficits. In each patient we measured the luminance-contrast threshold of being able to discriminate an orientation-target (Gabor-grating as a function of stimulation frequency (high 60Hz, low 8/10, no stimulation. Thresholds were determined using a standard staircase-protocol that is based on parameter estimation by sequential testing (PEST. We observed that under low frequency stimulation thresholds increased relative to no and high frequency stimulation in five out of six patients, suggesting that DBS of the PPN has a frequency-dependent impact on visual selection processes at a rather elementary perceptual level.

Inter- and intra-observer agreement of BI-RADS-based subjective visual estimation of amount of fibroglandular breast tissue with magnetic resonance imaging: comparison to automated quantitative assessment

International Nuclear Information System (INIS)

Wengert, G.J.; Helbich, T.H.; Woitek, R.; Kapetas, P.; Clauser, P.; Baltzer, P.A.; Vogl, W.D.; Weber, M.; Meyer-Baese, A.; Pinker, Katja

2016-01-01

To evaluate the inter-/intra-observer agreement of BI-RADS-based subjective visual estimation of the amount of fibroglandular tissue (FGT) with magnetic resonance imaging (MRI), and to investigate whether FGT assessment benefits from an automated, observer-independent, quantitative MRI measurement by comparing both approaches. Eighty women with no imaging abnormalities (BI-RADS 1 and 2) were included in this institutional review board (IRB)-approved prospective study. All women underwent un-enhanced breast MRI. Four radiologists independently assessed FGT with MRI by subjective visual estimation according to BI-RADS. Automated observer-independent quantitative measurement of FGT with MRI was performed using a previously described measurement system. Inter-/intra-observer agreements of qualitative and quantitative FGT measurements were assessed using Cohen's kappa (k). Inexperienced readers achieved moderate inter-/intra-observer agreement and experienced readers a substantial inter- and perfect intra-observer agreement for subjective visual estimation of FGT. Practice and experience reduced observer-dependency. Automated observer-independent quantitative measurement of FGT was successfully performed and revealed only fair to moderate agreement (k = 0.209-0.497) with subjective visual estimations of FGT. Subjective visual estimation of FGT with MRI shows moderate intra-/inter-observer agreement, which can be improved by practice and experience. Automated observer-independent quantitative measurements of FGT are necessary to allow a standardized risk evaluation. (orig.)

Inter- and intra-observer agreement of BI-RADS-based subjective visual estimation of amount of fibroglandular breast tissue with magnetic resonance imaging: comparison to automated quantitative assessment

Energy Technology Data Exchange (ETDEWEB)

Wengert, G.J.; Helbich, T.H.; Woitek, R.; Kapetas, P.; Clauser, P.; Baltzer, P.A. [Medical University of Vienna/ Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Vienna (Austria); Vogl, W.D. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Computational Imaging Research Lab, Wien (Austria); Weber, M. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of General and Pediatric Radiology, Wien (Austria); Meyer-Baese, A. [State University of Florida, Department of Scientific Computing in Medicine, Tallahassee, FL (United States); Pinker, Katja [Medical University of Vienna/ Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Division of Molecular and Gender Imaging, Vienna (Austria); State University of Florida, Department of Scientific Computing in Medicine, Tallahassee, FL (United States); Memorial Sloan-Kettering Cancer Center, Department of Radiology, Molecular Imaging and Therapy Services, New York City, NY (United States)

2016-11-15

To evaluate the inter-/intra-observer agreement of BI-RADS-based subjective visual estimation of the amount of fibroglandular tissue (FGT) with magnetic resonance imaging (MRI), and to investigate whether FGT assessment benefits from an automated, observer-independent, quantitative MRI measurement by comparing both approaches. Eighty women with no imaging abnormalities (BI-RADS 1 and 2) were included in this institutional review board (IRB)-approved prospective study. All women underwent un-enhanced breast MRI. Four radiologists independently assessed FGT with MRI by subjective visual estimation according to BI-RADS. Automated observer-independent quantitative measurement of FGT with MRI was performed using a previously described measurement system. Inter-/intra-observer agreements of qualitative and quantitative FGT measurements were assessed using Cohen's kappa (k). Inexperienced readers achieved moderate inter-/intra-observer agreement and experienced readers a substantial inter- and perfect intra-observer agreement for subjective visual estimation of FGT. Practice and experience reduced observer-dependency. Automated observer-independent quantitative measurement of FGT was successfully performed and revealed only fair to moderate agreement (k = 0.209-0.497) with subjective visual estimations of FGT. Subjective visual estimation of FGT with MRI shows moderate intra-/inter-observer agreement, which can be improved by practice and experience. Automated observer-independent quantitative measurements of FGT are necessary to allow a standardized risk evaluation. (orig.)

Analysis of relationship among visual evoked potential, oscillatory potential and visual acuity under stimulated weightlessness

Directory of Open Access Journals (Sweden)

Jun Zhao

2013-05-01

Full Text Available AIM: To observe the influence of head-down tilt simulated weightlessness on visual evoked potential(VEP, oscillatory potentials(OPsand visual acuity, and analyse the relationship among them. METHODS: Head-down tilt for -6° was adopted in 14 healthy volunteers. Distant visual acuity, near visual acuity, VEP and OPs were recorded before, two days and five days after trial. The record procedure of OPs followed the ISCEV standard for full-field clinical electroretinography(2008 update. RESULTS: Significant differences were detected in the amplitude of P100 waves and ∑OPs among various time points(P<0.05. But no relationship was observed among VEP, OPs and visual acuity. CONCLUSION: Head-down tilt simulated weightlessness induce the rearrange of blood of the whole body including eyes, which can make the change of visual electrophysiology but not visual acuity.

Visual Observation of Dissolution of Copper Ions from a Copper Electrode

Science.gov (United States)

Ikemoto, Isao; Saitou, Kouichi

2013-01-01

During electrolysis, to visually observe the conversion of a metal to its cation, either the cation or its complex ion should have a distinct color while the electrolyte solution must be colorless and transparent. A demonstration is described in which copper is used as the electrodes and sodium polyacrylate (a superabsorbent polymer) solution is…

Basic visual observation skills training course: Appendix B. Final report

Energy Technology Data Exchange (ETDEWEB)

Toquam, J.L.; Morris, F.A.; Griggs, J.R.

1995-06-01

The purpose of the basic visual observation skills course is to help safeguards inspectors evaluate and improve their skills in making observations during inspections and in evaluating and interpreting this information. The first 12 hours of the course provide training in five skill areas: perception and recognition; attention to detail; memory; mental imaging, mapping, and modeling skills; and judgment and decision making. Following this training is an integrating exercise involving a simulated safeguards inspection. This report contains the in-class exercises in the five skill areas; pre- and post-course exercises in closure, hidden figures, map memory, and mental rotations; the final examination; a training evaluation form; and the integrating exercise.

Basic visual observation skills training course: Appendix B. Final report

International Nuclear Information System (INIS)

Toquam, J.L.; Morris, F.A.; Griggs, J.R.

1995-06-01

The purpose of the basic visual observation skills course is to help safeguards inspectors evaluate and improve their skills in making observations during inspections and in evaluating and interpreting this information. The first 12 hours of the course provide training in five skill areas: perception and recognition; attention to detail; memory; mental imaging, mapping, and modeling skills; and judgment and decision making. Following this training is an integrating exercise involving a simulated safeguards inspection. This report contains the in-class exercises in the five skill areas; pre- and post-course exercises in closure, hidden figures, map memory, and mental rotations; the final examination; a training evaluation form; and the integrating exercise

Radical “Visual Capture” Observed in a Patient with Severe Visual Agnosia

Science.gov (United States)

Takaiwa, Akiko; Yoshimura, Hirokazu; Abe, Hirofumi; Terai, Satoshi

2003-01-01

We report the case of a 79-year-old female with visual agnosia due to brain infarction in the left posterior cerebral artery. She could recognize objects used in daily life rather well by touch (the number of objects correctly identified was 16 out of 20 presented objects), but she could not recognize them as well by vision (6 out of 20). In this case, it was expected that she would recognize them well when permitted to use touch and vision simultaneously. Our patient, however, performed poorly, producing 5 correct answers out of 20 in the Vision-and-Touch condition. It would be natural to think that visual capture functions when vision and touch provide contradictory information on concrete positions and shapes. However, in the present case, it functioned in spite of the visual deficit in recognizing objects. This should be called radical visual capture. By presenting detailed descriptions of her symptoms and neuropsychological and neuroradiological data, we clarify the characteristics of this type of capture. PMID:12719638

Radical “Visual Capture” Observed in a Patient with Severe Visual Agnosia

Directory of Open Access Journals (Sweden)

Akiko Takaiwa

2003-01-01

Full Text Available We report the case of a 79-year-old female with visual agnosia due to brain infarction in the left posterior cerebral artery. She could recognize objects used in daily life rather well by touch (the number of objects correctly identified was 16 out of 20 presented objects, but she could not recognize them as well by vision (6 out of 20. In this case, it was expected that she would recognize them well when permitted to use touch and vision simultaneously. Our patient, however, performed poorly, producing 5 correct answers out of 20 in the Vision-and-Touch condition. It would be natural to think that visual capture functions when vision and touch provide contradictory information on concrete positions and shapes. However, in the present case, it functioned in spite of the visual deficit in recognizing objects. This should be called radical visual capture. By presenting detailed descriptions of her symptoms and neuropsychological and neuroradiological data, we clarify the characteristics of this type of capture.

Visual observations of individual particle behaviour in gas and liquid fluidized beds

NARCIS (Netherlands)

Hartholt, G.P; Hoffmann, A.C; Janssen, L.P.B.M.

The behaviour of the individual particles in dense gas and liquid fluidized beds and the behaviour of the jetsam particles in gas fluidized beds containing binary mixtures of different density group B powders has been observed. These visualizations have been made by means of an optical probe fitted

Visual motion transforms visual space representations similarly throughout the human visual hierarchy.

Science.gov (United States)

Harvey, Ben M; Dumoulin, Serge O

2016-02-15

Several studies demonstrate that visual stimulus motion affects neural receptive fields and fMRI response amplitudes. Here we unite results of these two approaches and extend them by examining the effects of visual motion on neural position preferences throughout the hierarchy of human visual field maps. We measured population receptive field (pRF) properties using high-field fMRI (7T), characterizing position preferences simultaneously over large regions of the visual cortex. We measured pRFs properties using sine wave gratings in stationary apertures, moving at various speeds in either the direction of pRF measurement or the orthogonal direction. We find direction- and speed-dependent changes in pRF preferred position and size in all visual field maps examined, including V1, V3A, and the MT+ map TO1. These effects on pRF properties increase up the hierarchy of visual field maps. However, both within and between visual field maps the extent of pRF changes was approximately proportional to pRF size. This suggests that visual motion transforms the representation of visual space similarly throughout the visual hierarchy. Visual motion can also produce an illusory displacement of perceived stimulus position. We demonstrate perceptual displacements using the same stimulus configuration. In contrast to effects on pRF properties, perceptual displacements show only weak effects of motion speed, with far larger speed-independent effects. We describe a model where low-level mechanisms could underlie the observed effects on neural position preferences. We conclude that visual motion induces similar transformations of visuo-spatial representations throughout the visual hierarchy, which may arise through low-level mechanisms. Copyright © 2015 Elsevier Inc. All rights reserved.

User Driven Data Mining, Visualization and Decision Making for NOAA Observing System and Data Investments

Science.gov (United States)

Austin, M.

2016-12-01

The National Oceanic and Atmospheric Administration (NOAA) observing system enterprise represents a $2.4B annual investment. Earth observations from these systems are foundational to NOAA's mission to describe, understand, and predict the Earth's environment. NOAA's decision makers are charged with managing this complex portfolio of observing systems to serve the national interest effectively and efficiently. The Technology Planning & Integration for Observation (TPIO) Office currently maintains an observing system portfolio for NOAA's validated user observation requirements, observing capabilities, and resulting data products and services. TPIO performs data analytics to provide NOAA leadership business case recommendations for making sound budgetary decisions. Over the last year, TPIO has moved from massive spreadsheets to intuitive dashboards that enable Federal agencies as well as the general public the ability to explore user observation requirements and environmental observing systems that monitor and predict changes in the environment. This change has led to an organizational data management shift to analytics and visualizations by allowing analysts more time to focus on understanding the data, discovering insights, and effectively communicating the information to decision makers. Moving forward, the next step is to facilitate a cultural change toward self-serve data sharing across NOAA, other Federal agencies, and the public using intuitive data visualizations that answer relevant business questions for users of NOAA's Observing System Enterprise. Users and producers of environmental data will become aware of the need for enhancing communication to simplify information exchange to achieve multipurpose goals across a variety of disciplines. NOAA cannot achieve its goal of producing environmental intelligence without data that can be shared by multiple user communities. This presentation will describe where we are on this journey and will provide examples of

Looking to Learn: The Effects of Visual Guidance on Observational Learning of the Golf Swing.

Science.gov (United States)

D'Innocenzo, Giorgia; Gonzalez, Claudia C; Williams, A Mark; Bishop, Daniel T

2016-01-01

Skilled performers exhibit more efficient gaze patterns than less-skilled counterparts do and they look more frequently at task-relevant regions than at superfluous ones. We examine whether we may guide novices' gaze towards relevant regions during action observation in order to facilitate their learning of a complex motor skill. In a Pre-test-Post-test examination of changes in their execution of the full golf swing, 21 novices viewed one of three videos at intervention: i) a skilled golfer performing 10 swings (Free Viewing, FV); ii) the same video with transient colour cues superimposed to highlight key features of the setup (Visual Guidance; VG); iii) or a History of Golf video (Control). Participants in the visual guidance group spent significantly more time looking at cued areas than did the other two groups, a phenomenon that persisted after the cues had been removed. Moreover, the visual guidance group improved their swing execution at Post-test and on a Retention test one week later. Our results suggest that visual guidance to cued areas during observational learning of complex motor skills may accelerate acquisition of the skill.

A biologically inspired neural model for visual and proprioceptive integration including sensory training.

Science.gov (United States)

Saidi, Maryam; Towhidkhah, Farzad; Gharibzadeh, Shahriar; Lari, Abdolaziz Azizi

2013-12-01

Humans perceive the surrounding world by integration of information through different sensory modalities. Earlier models of multisensory integration rely mainly on traditional Bayesian and causal Bayesian inferences for single causal (source) and two causal (for two senses such as visual and auditory systems), respectively. In this paper a new recurrent neural model is presented for integration of visual and proprioceptive information. This model is based on population coding which is able to mimic multisensory integration of neural centers in the human brain. The simulation results agree with those achieved by casual Bayesian inference. The model can also simulate the sensory training process of visual and proprioceptive information in human. Training process in multisensory integration is a point with less attention in the literature before. The effect of proprioceptive training on multisensory perception was investigated through a set of experiments in our previous study. The current study, evaluates the effect of both modalities, i.e., visual and proprioceptive training and compares them with each other through a set of new experiments. In these experiments, the subject was asked to move his/her hand in a circle and estimate its position. The experiments were performed on eight subjects with proprioception training and eight subjects with visual training. Results of the experiments show three important points: (1) visual learning rate is significantly more than that of proprioception; (2) means of visual and proprioceptive errors are decreased by training but statistical analysis shows that this decrement is significant for proprioceptive error and non-significant for visual error, and (3) visual errors in training phase even in the beginning of it, is much less than errors of the main test stage because in the main test, the subject has to focus on two senses. The results of the experiments in this paper is in agreement with the results of the neural model

The mirror-neuron system and observational learning: Implications for the effectiveness of dynamic visualizations.

OpenAIRE

Van Gog, Tamara; Paas, Fred; Marcus, Nadine; Ayres, Paul; Sweller, John

2009-01-01

Van Gog, T., Paas, F., Marcus, N., Ayres, P., & Sweller, J. (2009). The mirror-neuron system and observational learning: Implications for the effectiveness of dynamic visualizations. Educational Psychology Review, 21, 21-30.

[Progressive visual agnosia].

Science.gov (United States)

Sugimoto, Azusa; Futamura, Akinori; Kawamura, Mitsuru

2011-10-01

Progressive visual agnosia was discovered in the 20th century following the discovery of classical non-progressive visual agnosia. In contrast to the classical type, which is caused by cerebral vascular disease or traumatic injury, progressive visual agnosia is a symptom of neurological degeneration. The condition of progressive visual loss, including visual agnosia, and posterior cerebral atrophy was named posterior cortical atrophy (PCA) by Benson et al. (1988). Progressive visual agnosia is also observed in semantic dementia (SD) and other degenerative diseases, but there is a difference in the subtype of visual agnosia associated with these diseases. Lissauer (1890) classified visual agnosia into apperceptive and associative types, and it in most cases, PCA is associated with the apperceptive type. However, SD patients exhibit symptoms of associative visual agnosia before changing to those of semantic memory disorder. Insights into progressive visual agnosia have helped us understand the visual system and discover how we "perceive" the outer world neuronally, with regard to consciousness. Although PCA is a type of atypical dementia, its diagnosis is important to enable patients to live better lives with appropriate functional support.

Enhanced peripheral visual processing in congenitally deaf humans is supported by multiple brain regions, including primary auditory cortex

Directory of Open Access Journals (Sweden)

Gregory D. Scott

2014-03-01

Full Text Available Brain reorganization associated with altered sensory experience clarifies the critical role of neuroplasticity in development. An example is enhanced peripheral visual processing associated with congenital deafness, but the neural systems supporting this have not been fully characterized. A gap in our understanding of deafness-enhanced peripheral vision is the contribution of primary auditory cortex. Previous studies of auditory cortex that use anatomical normalization across participants were limited by inter-subject variability of Heschl’s gyrus. In addition to reorganized auditory cortex (cross-modal plasticity, a second gap in our understanding is the contribution of altered modality-specific cortices (visual intramodal plasticity in this case, as well as supramodal and multisensory cortices, especially when target detection is required across contrasts. Here we address these gaps by comparing fMRI signal change for peripheral versus perifoveal visual stimulation (11-15° vs. 2°-7° in congenitally deaf and hearing participants in a blocked experimental design with two analytical approaches: a Heschl’s gyrus region of interest analysis and a whole brain analysis. Our results using individually-defined primary auditory cortex (Heschl’s gyrus indicate that fMRI signal change for more peripheral stimuli was greater than perifoveal in deaf but not in hearing participants. Whole-brain analyses revealed differences between deaf and hearing participants for peripheral versus perifoveal visual processing in extrastriate visual cortex including primary auditory cortex, MT+/V5, superior-temporal auditory and multisensory and/or supramodal regions, such as posterior parietal cortex, frontal eye fields, anterior cingulate, and supplementary eye fields. Overall, these data demonstrate the contribution of neuroplasticity in multiple systems including primary auditory cortex, supramodal and multisensory regions, to altered visual processing in

Radio Transmitters and Tower Locations, Layer includes all towers identified visually and include cellular and other communication towers., Published in 2008, 1:1200 (1in=100ft) scale, Noble County Government.

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Radio Transmitters and Tower Locations dataset current as of 2008. Layer includes all towers identified visually and include cellular and other communication towers..

Visual stimulation, {sup 1}H MR spectroscopy and fMRI of the human visual pathways

Energy Technology Data Exchange (ETDEWEB)

Boucard, Christine C.; Cornelissen, Frans W. [University of Groningen, Laboratory for Experimental Ophthalmology, Postbus 30001, Groningen (Netherlands); University of Groningen, BCN Neuro-imaging Center, Postbus 196, Groningen (Netherlands); Mostert, Jop P.; Keyser, Jacques De [University Hospital Groningen, Department of Neurology, Groningen (Netherlands); Oudkerk, Matthijs; Sijens, Paul E. [University Hospital Groningen, Department of Radiology, Groningen (Netherlands)

2005-01-01

The purpose was to assess changes in lactate content and other brain metabolites under visual stimulation in optical chiasm, optic radiations and occipital cortex using multiple voxel MR spectroscopy (MRS). {sup 1}H chemical shift imaging (CSI) examinations of transverse planes centered to include the above structures were performed in four subjects at an echo time of 135 ms. Functional MRI (fMRI) was used to confirm the presence of activity in the visual cortex during the visual stimulation. Spectral maps of optical chiasm were of poor quality due to field disturbances caused by nearby large blood vessels and/or eye movements. The optic radiations and the occipital lobe did not show any significant MR spectral change upon visual stimulation, i.e., the peak areas of inositol, choline, creatine, glutamate and N-acetylaspartate were not affected. Reproducible lactate signals were not observed. fMRI confirmed the presence of strong activations in stimulated visual cortex. Prolonged visual stimulation did not cause significant changes in MR spectra. Any signal observed near the 1.33 ppm resonance frequency of the lactate methyl-group was artifactual, originating from lipid signals from outside the volume of interest (VOI). Previous claims about changes in lactate levels in the visual cortex upon visual stimulation may have been based on such erroneous observations. (orig.)

Functional magnetic resonance imaging of the human primary visual cortex during visual stimulation

International Nuclear Information System (INIS)

Miki, Atsushi; Abe, Haruki; Nakajima, Takashi; Fujita, Motoi; Watanabe, Hiroyuki; Kuwabara, Takeo; Naruse, Shoji; Takagi, Mineo.

1995-01-01

Signal changes in the human primary visual cortex during visual stimulation were evaluated using non-invasive functional magnetic resonance imaging (fMRI). The experiments were performed on 10 normal human volunteers and 2 patients with homonymous hemianopsia, including one who was recovering from the exacerbation of multiple sclerosis. The visual stimuli were provided by a pattern generator using the checkerboard pattern for determining the visual evoked potential of full-field and hemifield stimulation. In normal volunteers, a signal increase was observed on the bilateral primary visual cortex during the full-field stimulation and on the contra-lateral cortex during hemifield stimulation. In the patient with homonymous hemianopsia after cerebral infarction, the signal change was clearly decreased on the affected side. In the other patient, the one recovering from multiple sclerosis with an almost normal visual field, the fMRI was within normal limits. These results suggest that it is possible to visualize the activation of the visual cortex during visual stimulation, and that there is a possibility of using this test as an objective method of visual field examination. (author)

AstroBlend: An astrophysical visualization package for Blender

Science.gov (United States)

Naiman, J. P.

2016-04-01

The rapid growth in scale and complexity of both computational and observational astrophysics over the past decade necessitates efficient and intuitive methods for examining and visualizing large datasets. Here, I present AstroBlend, an open-source Python library for use within the three dimensional modeling software, Blender. While Blender has been a popular open-source software among animators and visual effects artists, in recent years it has also become a tool for visualizing astrophysical datasets. AstroBlend combines the three dimensional capabilities of Blender with the analysis tools of the widely used astrophysical toolset, yt, to afford both computational and observational astrophysicists the ability to simultaneously analyze their data and create informative and appealing visualizations. The introduction of this package includes a description of features, work flow, and various example visualizations. A website - www.astroblend.com - has been developed which includes tutorials, and a gallery of example images and movies, along with links to downloadable data, three dimensional artistic models, and various other resources.

Visual observation of a heat pipe working characteristics

International Nuclear Information System (INIS)

Tsuyuzaki, Noriyoshi; Saito, Takashi; Ishigami, Shinya; Kawada, Michitaka; Konno, Masanobu; Kaminaga, Fumito; Okamoto, Yoshizo.

1988-10-01

When the heat pipe is used in a nuclear engineering field, it is indispensable to understand transient characteristics of an accident condition as well as in a steady state at a normal operation. However there have been few informations about the transient characteristics of a heat pipe in case of rapid temperature or heat load change in an evaporator section. The purpose of this study is to examine transient and steady state characteristics of a gravity assisted heat pipe and variable conductance heat pipe(VCHP) which will be used in a neutron irradiation capsule. This report presents results of visual observation of boiling and condensation patterns on steady state or transient condition in a visible heat pipe made of a glass. The response time of the heat pipe is on the order of a few seconds when the temperature of the evaporator part is kept above the operating temperature. (author)

Observations of visual sensations produced by Cerenkov radiation from high-energy electrons

International Nuclear Information System (INIS)

Steidley, K.D.; Eastman, R.M.; Stabile, R.J.

1989-01-01

Ten cancer patients whose eyes were therapeutically irradiated with 6-18 MeV electrons reported visual light sensations. Nine reported seeing blue light and one reported seeing white light. Controls reported seeing no light. Additionally, tests with patients ruled out the x-ray contamination of the electron beam as being important. The photon yield due to Cerenkov radiation produced by radium and its daughters for both electrons and gamma rays was calculated; it was found to account for a turn-of-the-century human observation of the radium phosphene. We conclude that the dominant mechanism of this phosphene is Cerenkov radiation, primarily from betas. From our own patient data, based on the color seen and the Cerenkov production rates, we conclude that the dominant mechanism is Cerenkov radiation and that high-energy electrons are an example of particle induced visual sensations

Correlation between observation task performance and visual acuity, contrast sensitivity and environmental light in a simulated maritime study.

Science.gov (United States)

Koefoed, Vilhelm F; Assmuss, Jörg; Høvding, Gunnar

2018-03-25

To examine the relevance of visual acuity (VA) and index of contrast sensitivity (ICS) as predictors for visual observation task performance in a maritime environment. Sixty naval cadets were recruited to a study on observation tasks in a simulated maritime environment under three different light settings. Their ICS were computed based on contrast sensitivity (CS) data recorded by Optec 6500 and CSV-1000E CS tests. The correlation between object identification distance and VA/ICS was examined by stepwise linear regression. The object detection distance was significantly correlated to the level of environmental light (p maritime environment may presumably be ascribed to the normal and uniform visual capacity in all our study subjects. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Top-down influences on visual attention during listening are modulated by observer sex.

Science.gov (United States)

Shen, John; Itti, Laurent

2012-07-15

In conversation, women have a small advantage in decoding non-verbal communication compared to men. In light of these findings, we sought to determine whether sex differences also existed in visual attention during a related listening task, and if so, if the differences existed among attention to high-level aspects of the scene or to conspicuous visual features. Using eye-tracking and computational techniques, we present direct evidence that men and women orient attention differently during conversational listening. We tracked the eyes of 15 men and 19 women who watched and listened to 84 clips featuring 12 different speakers in various outdoor settings. At the fixation following each saccadic eye movement, we analyzed the type of object that was fixated. Men gazed more often at the mouth and women at the eyes of the speaker. Women more often exhibited "distracted" saccades directed away from the speaker and towards a background scene element. Examining the multi-scale center-surround variation in low-level visual features (static: color, intensity, orientation, and dynamic: motion energy), we found that men consistently selected regions which expressed more variation in dynamic features, which can be attributed to a male preference for motion and a female preference for areas that may contain nonverbal information about the speaker. In sum, significant differences were observed, which we speculate arise from different integration strategies of visual cues in selecting the final target of attention. Our findings have implications for studies of sex in nonverbal communication, as well as for more predictive models of visual attention. Published by Elsevier Ltd.

Observation of Depictive Versus Tracing Gestures Selectively Aids Verbal Versus Visual-Spatial Learning in Primary School Children

NARCIS (Netherlands)

van Wermeskerken, Margot; Fijan, Nathalie; Eielts, Charly; Pouw, Wim T. J. L.

2016-01-01

Previous research has established that gesture observation aids learning in children. The current study examined whether observation of gestures (i.e. depictive and tracing gestures) differentially affected verbal and visual-spatial retention when learning a route and its street names. Specifically,

Observability Analysis of a Matrix Kalman Filter-Based Navigation System Using Visual/Inertial/Magnetic Sensors

Directory of Open Access Journals (Sweden)

Guohu Feng

2012-06-01

Full Text Available A matrix Kalman filter (MKF has been implemented for an integrated navigation system using visual/inertial/magnetic sensors. The MKF rearranges the original nonlinear process model in a pseudo-linear process model. We employ the observability rank criterion based on Lie derivatives to verify the conditions under which the nonlinear system is observable. It has been proved that such observability conditions are: (a at least one degree of rotational freedom is excited, and (b at least two linearly independent horizontal lines and one vertical line are observed. Experimental results have validated the correctness of these observability conditions.

A different view on the checkerboard? Alterations in early and late visually evoked EEG potentials in Asperger observers.

Directory of Open Access Journals (Sweden)

Juergen Kornmeier

Full Text Available BACKGROUND: Asperger Autism is a lifelong psychiatric condition with highly circumscribed interests and routines, problems in social cognition, verbal and nonverbal communication, and also perceptual abnormalities with sensory hypersensitivity. To objectify both lower-level visual and cognitive alterations we looked for differences in visual event-related potentials (EEG between Asperger observers and matched controls while they observed simple checkerboard stimuli. METHODS: In a balanced oddball paradigm checkerboards of two checksizes (0.6° and 1.2° were presented with different frequencies. Participants counted the occurrence times of the rare fine or rare coarse checkerboards in different experimental conditions. We focused on early visual ERP differences as a function of checkerboard size and the classical P3b ERP component as an indicator of cognitive processing. RESULTS: We found an early (100-200 ms after stimulus onset occipital ERP effect of checkerboard size (dominant spatial frequency. This effect was weaker in the Asperger than in the control observers. Further a typical parietal/central oddball-P3b occurred at 500 ms with the rare checkerboards. The P3b showed a right-hemispheric lateralization, which was more prominent in Asperger than in control observers. DISCUSSION: The difference in the early occipital ERP effect between the two groups may be a physiological marker of differences in the processing of small visual details in Asperger observers compared to normal controls. The stronger lateralization of the P3b in Asperger observers may indicate a stronger involvement of the right-hemispheric network of bottom-up attention. The lateralization of the P3b signal might be a compensatory consequence of the compromised early checksize effect. Higher-level analytical information processing units may need to compensate for difficulties in low-level signal analysis.

Hydrothermal Diamond Anvil Cell (HDAC): From Visual Observation to X-ray Absorption Spectroscopy

Science.gov (United States)

Bassett, W. A.; Mibe, K.

2006-05-01

A fluid sample contained in a Re gasket between two diamond anvils can be subjected to pressures up to 2.5 GPa and temperatures up to 1200°C in a resistively heated hydrothermal diamond anvil cell (HDAC). Thermocouples are used to measure temperature. The constant-volume sample chamber permits isochoric measurements that can be used to determine pressure from the equation of state of H2O and to map phases and properties in P-T space. A movie of reactions between K-feldspar and water up to 2.5 GPa and 880°C illustrates the use of visual observations for mapping coexisting solution, melt, and solid phases. X-ray absorption spectroscopy of ZnBr2 in solution up to 500°C and 500 MPa shows hydrogen bond breaking in the hydration shells of the ZnBr42- and Br- ions with increasing temperature. In other studies the stability field of ikaite (CaCO3·6H2O) has been mapped by visual observation and Raman spectroscopy; the phases of montmorillonite have been mapped by X-ray diffraction; and the leaching of Pb from zircon has been measured by X-ray microprobe.

United States Naval Academy Polar Science Program's Visual Arctic Observing Buoys; The IceGoat

Science.gov (United States)

Woods, J. E.; Clemente-Colon, P.; Nghiem, S. V.; Rigor, I.; Valentic, T. A.

2012-12-01

The U.S. Naval Academy Oceanography Department currently has a curriculum based Polar Science Program (USNA PSP). Within the PSP there is an Arctic Buoy Program (ABP) student research component that will include the design, build, testing and deployment of Arctic Buoys. Establishing an active, field-research program in Polar Science will greatly enhance Midshipman education and research, as well as introduce future Naval Officers to the Arctic environment. The Oceanography Department has engaged the USNA Ocean Engineering, Systems Engineering, Aerospace Engineering, and Computer Science Departments and developed a USNA Visual Arctic Observing Buoy, IceGoat1, which was designed, built, and deployed by midshipmen. The experience gained through Polar field studies and data derived from these buoys will be used to enhance course materials and laboratories and will also be used directly in Midshipman independent research projects. The USNA PSP successfully deployed IceGoat1 during the BROMEX 2012 field campaign out of Barrow, AK in March 2012. This buoy reports near real-time observation of Air Temperature, Sea Temperature, Atmospheric Pressure, Position and Images from 2 mounted webcams. The importance of this unique type of buoy being inserted into the U.S. Interagency Arctic Buoy Program and the International Arctic Buoy Programme (USIABP/IABP) array is cross validating satellite observations of sea ice cover in the Arctic with the buoys webcams. We also propose to develop multiple sensor packages for the IceGoat to include a more robust weather suite, and a passive acoustic hydrophone. Remote cameras on buoys have provided crucial qualitative information that complements the quantitative measurements of geophysical parameters. For example, the mechanical anemometers on the IABP Polar Arctic Weather Station at the North Pole Environmental Observatory (NPEO) have at times reported zero winds speeds, and inspection of the images from the NPEO cameras have showed

HST Observations of Astrophysically Important Visual Binaries

Science.gov (United States)

Bond, Howard

2015-10-01

We propose to continue our long-term program of astrometry of close visual binaries, with the primary goal of determining purely dynamical masses for 3 important main-sequence stars and 9 white dwarfs (WDs). A secondary aim is to set limits on third bodies in the systems down to planetary mass. Three of our targets are naked-eye stars with much fainter companions that are extremely difficult to image from the ground. Our other 2 targets are double WDs, whose small separations and faintness likewise make them difficult to measure using ground-based techniques. Observations have been completed for a 3rd double WD.The bright stars, to be imaged with WFC3, are: (1) Procyon (P = 40.83 yr), containing a bright F star and a much fainter WD companion. With the continued monitoring proposed here, we will obtain masses to an accuracy of better than 1%, providing a testbed for theories of both Sun-like stars and WDs. (2) Sirius (P = 50.14 yr), an A-type star also having a faint WD companion, Sirius B, the nearest and brightest of all WDs. (3) Mu Cas (P = 21.08 yr), a nearby metal-deficient G dwarf for which accurate masses will lead to the stars' helium contents, with cosmological implications. The faint double WDs, to be observed with FGS, are: (1) G 107-70 (P = 18.84 yr), and (2) WD 1818+126 (P = 12.19 yr). Our astrometry of these systems will add 4 accurate masses to the handful of WD masses that are directly known from dynamical measurements. The FGS measurements will also provide precise parallaxes for the systems, a necessary ingredient in the mass determinations.

EDA-BASED ESTIMATION OF VISUAL ATTENTION BY OBSERVATION OF EYE BLINK FREQUENCY

OpenAIRE

Sakai, Tsugunosuke; Tamaki, Haruya; Ota, Yosuke; Egusa, Ryohei; Inagaki, Shigenori; Kusunoki, Fusako; Sugimoto, Masanori; Mizoguchi, Hiroshi

2017-01-01

This paper describes the relationship between visual attention and eye blink frequency. In an experiment, we prompted the activation of a subject's visual attention and examined the influence of visual attention (as measured using electrodermal activity (EDA), which is meaningfully correlated with visual attention) on the subject's eye blink frequency. Experimental results show that engagement of visual attention decreased eye blink frequency and that when visual attention was not activated, ...

Learning Visualizations by Analogy: Promoting Visual Literacy through Visualization Morphing.

Science.gov (United States)

Ruchikachorn, Puripant; Mueller, Klaus

2015-09-01

We propose the concept of teaching (and learning) unfamiliar visualizations by analogy, that is, demonstrating an unfamiliar visualization method by linking it to another more familiar one, where the in-betweens are designed to bridge the gap of these two visualizations and explain the difference in a gradual manner. As opposed to a textual description, our morphing explains an unfamiliar visualization through purely visual means. We demonstrate our idea by ways of four visualization pair examples: data table and parallel coordinates, scatterplot matrix and hyperbox, linear chart and spiral chart, and hierarchical pie chart and treemap. The analogy is commutative i.e. any member of the pair can be the unfamiliar visualization. A series of studies showed that this new paradigm can be an effective teaching tool. The participants could understand the unfamiliar visualization methods in all of the four pairs either fully or at least significantly better after they observed or interacted with the transitions from the familiar counterpart. The four examples suggest how helpful visualization pairings be identified and they will hopefully inspire other visualization morphings and associated transition strategies to be identified.

Gender differences in episodic memory and visual working memory including the effects of age.

Science.gov (United States)

Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

2013-01-01

Analysing the relationship between gender and memory, and examining the effects of age on the overall memory-related functioning, are the ongoing goals of psychological research. The present study examined gender and age group differences in episodic memory with respect to the type of task. In addition, these subgroup differences were also analysed in visual working memory. A sample of 366 women and 330 men, aged between 16 and 69 years of age, participated in the current study. Results indicate that women outperformed men on auditory memory tasks, whereas male adolescents and older male adults showed higher level performances on visual episodic and visual working memory measures. However, the size of gender-linked effects varied somewhat across age groups. Furthermore, results partly support a declining performance on episodic memory and visual working memory measures with increasing age. Although age-related losses in episodic memory could not be explained by a decreasing verbal and visuospatial ability with age, women's advantage in auditory episodic memory could be explained by their advantage in verbal ability. Men's higher level visual episodic memory performance was found to result from their advantage in visuospatial ability. Finally, possible methodological, biological, and cognitive explanations for the current findings are discussed.

Visual Literacy and Visual Thinking.

Science.gov (United States)

Hortin, John A.

It is proposed that visual literacy be defined as the ability to understand (read) and use (write) images and to think and learn in terms of images. This definition includes three basic principles: (1) visuals are a language and thus analogous to verbal language; (2) a visually literate person should be able to understand (read) images and use…

An assessment of the effectiveness of personal visual observation for a uranium enrichment facility

International Nuclear Information System (INIS)

Ohno, Fubito; Okamoto, Tsuyoshi; Yokochi, Akira; Nidaira, Kazuo

2002-01-01

In a centrifuge uranium enrichment facility, a cascade producing low enriched uranium is composed of a large number of UF 6 gas centrifuges interconnected with pipes. If new advanced centrifuges are developed and they are installed in the facility, the number of centrifuges in the unit cascade will decrease. This means that the number of pipes connecting centrifuges will decrease also. In addition, if integrated type centrifuges containing a few tens of centrifuges are adopted for economical reasons, the number of pipes will further decrease. The smaller the number of pipes, the less the labor required to reconstruct the cascade by changing the piping arrangement so that it can produce highly enriched uranium. Because personal visual observation by inspectors is considered as one of safeguards measures against changing the piping arrangement, its effectiveness is assessed in this study. An inspection in a cascade area is modeled as a two-person non-cooperative game between an inspector and a facility operator. As a result, it is suggested that personal visual observation of the piping arrangement is worth carrying out in an advanced centrifuge uranium enrichment facility. (author)

Assessment of the effectiveness of personal visual observation as a safeguards measure in a uranium enrichment facility

International Nuclear Information System (INIS)

Ohno, Fubito; Okamoto, Tsuyoshi; Yokochi, Akira; Nidaira, Kazuo

2003-01-01

In a centrifuge enrichment facility, a cascade that produces low enriched uranium is composed of a large number of UF 6 gas centrifuges interconnected with pipes. It is possible to divert the cascade to the illegal production of highly enriched uranium (HEU) by changing the piping arrangement within the cascade. If integrated type centrifuges that contain a few tens of advanced centrifuges are introduced into the facility, the number of pipes will greatly decrease. The smaller the number of pipes, the less the labor required to change the piping arrangement. Because personal visual observation by an inspector is considered as one of measures against changing the piping arrangement, its effectiveness is assessed in this study. First, a model centrifuge enrichment facility that has a capacity of 2,400 ton-SWU/y is designed. In this model facility, integrated type centrifuges that contain advanced centrifuges are installed. Second, the diversion path analysis is carried out for the model facility under the assumption that a facility operator's goal is to produce 75 kg of HEU with 20% enrichment in a month. The analysis shows that, in our assumed diversion path, changes of the piping arrangement can be certainly detected by personal visual observation of a part of pipes connected with integrated type centrifuges that compose the cascade diverted to the HEU production. Finally, inspections in a cascade area are modeled as two-person noncooperative games between the inspector and the facility operator. As a result, it is found that all the cascades in the model facility will be investigated if the inspector can devote the inspection effort of 0.83 man-day per month to personal visual observation in the cascade area. Therefore, it is suggested that personal visual observation of the piping arrangement is worth carrying out in a uranium enrichment facility where integrated type centrifuges that contain advanced centrifuges are installed. (author)

Observing before Learning: Visual Material for the Learning of English as a Foreign Language

Directory of Open Access Journals (Sweden)

Diana Benavides

2009-12-01

Full Text Available This article is a report of the findings of a research project developed in a Colombian school, Academia La Salle San Benildo, as a requirement for the B.A. degree in Modern Languages at La Salle University. The goal of this project is to describe the impact of working with visual material with the students of fifth and third grades. The data collected throughout the process include an interview, a survey, students’ work, and journals kept by the student teachers. The results of the analysis of the research show the importance of the application of visual material in the teaching process.

Visual impairment in children with congenital Zika syndrome.

Science.gov (United States)

Ventura, Liana O; Ventura, Camila V; Lawrence, Linda; van der Linden, Vanessa; van der Linden, Ana; Gois, Adriana L; Cavalcanti, Milena M; Barros, Eveline A; Dias, Natalia C; Berrocal, Audina M; Miller, Marilyn T

2017-08-01

To describe the visual impairment associated with ocular and neurological abnormalities in a cohort of children with congenital Zika syndrome (CZS). This cross-sectional study included infants with microcephaly born in Pernambuco, Brazil, from May to December 2015. Immunoglobulin M antibody capture enzyme-linked immunosorbent assay for the Zika virus on the cerebrospinal fluid samples was positive for all infants. Clinical evaluation consisted of comprehensive ophthalmologic examination including visual acuity, visual function assessment, visual developmental milestone, neurologic examination, and neuroimaging. A total of 32 infants (18 males [56%]) were included. Mean age at examination was 5.7 ± 0.9 months (range, 4-7 months). Visual function and visual developmental milestone could not be tested in 1 child (3%). Visual impairment was detected in 32 infants (100%). Retinal and/or optic nerve findings were observed in 14 patients (44%). There was no statistical difference between the patients with ocular findings and those without (P = 0.180). All patients (100%) demonstrated neurological and neuroimaging abnormalities; 3 (9%) presented with late-onset of microcephaly. Children with CZS demonstrated visual impairment regardless of retina and/or optic nerve abnormalities. This finding suggests that cortical/cerebral visual impairment may be the most common cause of blindness identified in children with CZS. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Experimental demonstration and visual observation of dust trapping in an electron storage ring

Directory of Open Access Journals (Sweden)

Yasunori Tanimoto

2009-11-01

Full Text Available Sudden decreases in the beam lifetime, which are attributed to the dust trappings, sometimes occur at the electron storage ring Photon Factory Advanced Ring (PF-AR. Since these dust events cause difficulties in user operations, we have been carefully observing this phenomenon for many years. Our observations indicated that the dust trappings could be caused by electric discharges in vacuum ducts. In order to demonstrate this hypothesis experimentally, we designed a new vacuum device that intentionally generates electric discharges and installed it in PF-AR. Using this device, we could repeatedly induce sudden decreases in the beam lifetime because of the generated electric discharge. We also detected decreases in the beam lifetime caused by mechanical movement of the electrodes in the device. Moreover, we could visually observe the dust trapping phenomenon; the trapped dust particle was observed by two video cameras and appeared as a luminous body that resembled a shooting star. This was the first direct observation of a luminous dust particle trapped by the electron beam.

Armstrong Laboratory Space Visual Function Tester Program

Science.gov (United States)

Oneal, Melvin R.; Task, H. Lee; Gleason, Gerald A.

1992-01-01

Viewgraphs on space visual function tester program are presented. Many astronauts and cosmonauts have commented on apparent changes in their vision while on-orbit. Comments have included descriptions of earth features and objects that would suggest enhanced distance visual acuity. In contrast, some cosmonaut observations suggest a slight loss in their object discrimination during initial space flight. Astronauts have also mentioned a decreased near vision capability that did not recover to normal until return to earth. Duntley space vision experiment, USSR space vision experiments, and visual function testers are described.

A visualization environment for supercomputing-based applications in computational mechanics

Energy Technology Data Exchange (ETDEWEB)

Pavlakos, C.J.; Schoof, L.A.; Mareda, J.F.

1993-06-01

In this paper, we characterize a visualization environment that has been designed and prototyped for a large community of scientists and engineers, with an emphasis in superconducting-based computational mechanics. The proposed environment makes use of a visualization server concept to provide effective, interactive visualization to the user`s desktop. Benefits of using the visualization server approach are discussed. Some thoughts regarding desirable features for visualization server hardware architectures are also addressed. A brief discussion of the software environment is included. The paper concludes by summarizing certain observations which we have made regarding the implementation of such visualization environments.

[Dice test--a simple method for assessment of visual acuity in infants with visual deficits].

Science.gov (United States)

Rohrschneider, K; Brill, B; Bayer, Y; Ahrens, P

2010-07-01

Determination of visual acuity in low vision infants or patients with additional cerebral retardation is difficult. In our low vision department we used dice of different sizes and colors as well as other defined objects to determine visual acuity (VA). In this study we compared the results of the dice test with conventional tests for measurement of visual acuity. A total of 88 children with different causes of visual impairment e.g. albinism, retinal scars, retinopathy of prematurity (ROP), achromatopsia and optic atrophy etc., were included in this longitudinal study. Median follow-up time was 8.7 years (range 2.9-18.9 years). The first reliable examination was performed between the ages of 4 and 24 months (median 11 months). We estimated VA depending on the edge length of the dice, which were recognized at a distance of 30 cm, while 4 mm complied with VA 20/200. Best corrected binocular visual acuity was compared between the dice test, measurement with the Lea symbols and with numbers or Landolt rings. Estimation of visual acuity using the dice test was possible at the end of the first year of life (median 11 months, range 4-27 months). Although observation is limited to visual acuity results in the low vision range between light reaction and 20/120 there was nearly complete agreement between all three VA measurements. Visual acuity ranged from light perception to 20/20 with a median of 20/100. In 39 patients visual acuity was 20/200 or less at the end of the observation period. Visual acuity estimation overestimated visual acuity only in 5 out of the 88 patients, while in all of the patients with later acuity measurements better than 20/200, our best value of 20/200 was achieved. Using simple visual objects, such as dice with different colors and size down to an edge length of 4 mm, it is possible to estimate visual acuity in low vision infants within the first year of life. This option is also very helpful in patients who are not able to perform other visual

A comunicação como barreira à inclusão de alunos com deficiência visual em aulas de mecânica Communication as a barrier for including visual handicapped pupils in mechanics classes

Directory of Open Access Journals (Sweden)

Eder Pires de Camargo

2010-01-01

Full Text Available O presente artigo encontra-se inserido em um estudo que busca compreender as principais barreiras para a inclusão de alunos com deficiência visual no contexto do ensino de física. Focalizando aulas de mecânica, analisa as dificuldades comunicacionais entre licenciandos e discentes com deficiência visual. Para tal, enfatiza as estruturas empírica e semântico-sensorial das linguagens utilizadas, indicando fatores geradores de dificuldades de acessibilidade às informações veiculadas. Recomenda, ainda, alternativas que se destinam a dar condições à participação efetiva do discente com deficiência visual no processo comunicativo. Conclui afirmando que a comunicação representa a principal barreira à participação efetiva de alunos com deficiência visual em aulas de mecânica, e enfatiza a importância da criação de canais comunicacionais adequados como condição básica à inclusão desses alunos.This paper is a part of a broader study aiming to understand the main barriers for including visual handicapped pupils in physics' teaching contexts. It analyzes communication difficulties between future physics teachers and visual handicapped pupils during Mechanics classes. It emphasizes the empirical and semantic-sensorial structures of the languages used, indicating factors which produce the accessibility difficulties for the spread of information. It recommends alternatives in order to make possible the effective participation of visual handicapped pupils in the communicative process. It concludes that communication represents the main barrier to the effective visual handicapped pupils' participation in optics classes and emphasizes the importance of creating communicatively appropriate channels as a basic condition for including these students.

Mathematical pointing model establishment of the visual tracking theodolite for satellites in two kinds of observation methods.

Science.gov (United States)

Zhang, Yuncheng

The mathematical pointing model is establishment of the visual tracking theodolite for satellites in two kinds of observation methods at Yunnan Observatory, which is related to the digitalisation reform and the optical-electronic technique reform, is introduced respectively in this paper.

Visual memory and visual perception: when memory improves visual search.

Science.gov (United States)

Riou, Benoit; Lesourd, Mathieu; Brunel, Lionel; Versace, Rémy

2011-08-01

This study examined the relationship between memory and perception in order to identify the influence of a memory dimension in perceptual processing. Our aim was to determine whether the variation of typical size between items (i.e., the size in real life) affects visual search. In two experiments, the congruency between typical size difference and perceptual size difference was manipulated in a visual search task. We observed that congruency between the typical and perceptual size differences decreased reaction times in the visual search (Exp. 1), and noncongruency between these two differences increased reaction times in the visual search (Exp. 2). We argue that these results highlight that memory and perception share some resources and reveal the intervention of typical size difference on the computation of the perceptual size difference.

Coding the presence of visual objects in a recurrent neural network of visual cortex.

Science.gov (United States)

Zwickel, Timm; Wachtler, Thomas; Eckhorn, Reinhard

2007-01-01

Before we can recognize a visual object, our visual system has to segregate it from its background. This requires a fast mechanism for establishing the presence and location of objects independently of their identity. Recently, border-ownership neurons were recorded in monkey visual cortex which might be involved in this task [Zhou, H., Friedmann, H., von der Heydt, R., 2000. Coding of border ownership in monkey visual cortex. J. Neurosci. 20 (17), 6594-6611]. In order to explain the basic mechanisms required for fast coding of object presence, we have developed a neural network model of visual cortex consisting of three stages. Feed-forward and lateral connections support coding of Gestalt properties, including similarity, good continuation, and convexity. Neurons of the highest area respond to the presence of an object and encode its position, invariant of its form. Feedback connections to the lowest area facilitate orientation detectors activated by contours belonging to potential objects, and thus generate the experimentally observed border-ownership property. This feedback control acts fast and significantly improves the figure-ground segregation required for the consecutive task of object recognition.

Exploring hospitality within hospital meals by means of visual methodologies

DEFF Research Database (Denmark)

Justesen, Lise

2016-01-01

ABSTRACT This paper reflects the application of visual methodologies adapted in an explorative study on hospitality and hospital meals. It takes point of departure in a multi-sited ethnographic fieldwork placed at a general hospital in 2012. Visual methodologies were applied in multiple ways....... This includes visual methodologies as part of observation and interview strategies. The paper presents and discusses how the application of different visual methodologies can contribute to the construction of ethnographical knowledge on hospitality and hospital meals. Finally ethical considerations as well...

Visualizing SPH Cataclysmic Variable Accretion Disk Simulations with Blender

Science.gov (United States)

Kent, Brian R.; Wood, Matthew A.

2015-01-01

We present innovative ways to use Blender, a 3D graphics package, to visualize smoothed particle hydrodynamics particle data of cataclysmic variable accretion disks. We focus on the methods of shape key data constructs to increasedata i/o and manipulation speed. The implementation of the methods outlined allow for compositing of the various visualization layers into a final animation. The viewing of the disk in 3D from different angles can allow for a visual analysisof the physical system and orbits. The techniques have a wide ranging set of applications in astronomical visualization,including both observation and theoretical data.

Poster: Observing change in crowded data sets in 3D space - Visualizing gene expression in human tissues

KAUST Repository

Rogowski, Marcin

2013-03-01

We have been confronted with a real-world problem of visualizing and observing change of gene expression between different human tissues. In this paper, we are presenting a universal representation space based on two-dimensional gel electrophoresis as opposed to force-directed layouts encountered most often in similar problems. We are discussing the methods we devised to make observing change more convenient in a 3D virtual reality environment. © 2013 IEEE.

Visual intelligence Microsoft tools and techniques for visualizing data

CERN Document Server

Stacey, Mark; Jorgensen, Adam

2013-01-01

Go beyond design concepts and learn to build state-of-the-art visualizations The visualization experts at Microsoft's Pragmatic Works have created a full-color, step-by-step guide to building specific types of visualizations. The book thoroughly covers the Microsoft toolset for data analysis and visualization, including Excel, and explores best practices for choosing a data visualization design, selecting tools from the Microsoft stack, and building a dynamic data visualization from start to finish. You'll examine different types of visualizations, their strengths and weaknesses, a

Visualizing Dynamic Bitcoin Transaction Patterns.

Science.gov (United States)

McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J

2016-06-01

This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network.

Visualizing Dynamic Bitcoin Transaction Patterns

Science.gov (United States)

McGinn, Dan; Birch, David; Akroyd, David; Molina-Solana, Miguel; Guo, Yike; Knottenbelt, William J.

2016-01-01

Abstract This work presents a systemic top-down visualization of Bitcoin transaction activity to explore dynamically generated patterns of algorithmic behavior. Bitcoin dominates the cryptocurrency markets and presents researchers with a rich source of real-time transactional data. The pseudonymous yet public nature of the data presents opportunities for the discovery of human and algorithmic behavioral patterns of interest to many parties such as financial regulators, protocol designers, and security analysts. However, retaining visual fidelity to the underlying data to retain a fuller understanding of activity within the network remains challenging, particularly in real time. We expose an effective force-directed graph visualization employed in our large-scale data observation facility to accelerate this data exploration and derive useful insight among domain experts and the general public alike. The high-fidelity visualizations demonstrated in this article allowed for collaborative discovery of unexpected high frequency transaction patterns, including automated laundering operations, and the evolution of multiple distinct algorithmic denial of service attacks on the Bitcoin network. PMID:27441715

Gait in children with cerebral palsy : observer reliability of Physician Rating Scale and Edinburgh Visual Gait Analysis Interval Testing scale

NARCIS (Netherlands)

Maathuis, KGB; van der Schans, CP; van Iperen, A; Rietman, HS; Geertzen, JHB

2005-01-01

The aim of this study was to test the inter- and intra-observer reliability of the Physician Rating Scale (PRS) and the Edinburgh Visual Gait Analysis Interval Testing (GAIT) scale for use in children with cerebral palsy (CP). Both assessment scales are quantitative observational scales, evaluating

Do gender differences in audio-visual benefit and visual influence in audio-visual speech perception emerge with age?

Directory of Open Access Journals (Sweden)

Magnus eAlm

2015-07-01

Full Text Available Gender and age have been found to affect adults’ audio-visual (AV speech perception. However, research on adult aging focuses on adults over 60 years, who have an increasing likelihood for cognitive and sensory decline, which may confound positive effects of age-related AV-experience and its interaction with gender. Observed age and gender differences in AV speech perception may also depend on measurement sensitivity and AV task difficulty. Consequently both AV benefit and visual influence were used to measure visual contribution for gender-balanced groups of young (20-30 years and middle-aged adults (50-60 years with task difficulty varied using AV syllables from different talkers in alternative auditory backgrounds. Females had better speech-reading performance than males. Whereas no gender differences in AV benefit or visual influence were observed for young adults, visually influenced responses were significantly greater for middle-aged females than middle-aged males. That speech-reading performance did not influence AV benefit may be explained by visual speech extraction and AV integration constituting independent abilities. Contrastingly, the gender difference in visually influenced responses in middle adulthood may reflect an experience-related shift in females’ general AV perceptual strategy. Although young females’ speech-reading proficiency may not readily contribute to greater visual influence, between young and middle-adulthood recurrent confirmation of the contribution of visual cues induced by speech-reading proficiency may gradually shift females AV perceptual strategy towards more visually dominated responses.

Novel Scientific Visualization Interfaces for Interactive Information Visualization and Sharing

Science.gov (United States)

Demir, I.; Krajewski, W. F.

2012-12-01

As geoscientists are confronted with increasingly massive datasets from environmental observations to simulations, one of the biggest challenges is having the right tools to gain scientific insight from the data and communicate the understanding to stakeholders. Recent developments in web technologies make it easy to manage, visualize and share large data sets with general public. Novel visualization techniques and dynamic user interfaces allow users to interact with data, and modify the parameters to create custom views of the data to gain insight from simulations and environmental observations. This requires developing new data models and intelligent knowledge discovery techniques to explore and extract information from complex computational simulations or large data repositories. Scientific visualization will be an increasingly important component to build comprehensive environmental information platforms. This presentation provides an overview of the trends and challenges in the field of scientific visualization, and demonstrates information visualization and communication tools in the Iowa Flood Information System (IFIS), developed within the light of these challenges. The IFIS is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to and visualization of flood inundation maps, real-time flood conditions, flood forecasts both short-term and seasonal, and other flood-related data for communities in Iowa. The key element of the system's architecture is the notion of community. Locations of the communities, those near streams and rivers, define basin boundaries. The IFIS provides community-centric watershed and river characteristics, weather (rainfall) conditions, and streamflow data and visualization tools. Interactive interfaces allow access to inundation maps for different stage and return period values, and flooding scenarios with contributions from multiple rivers. Real-time and historical data of water levels, gauge heights, and

Drivers' phone use at red traffic lights: a roadside observation study comparing calls and visual-manual interactions.

Science.gov (United States)

Huth, Véronique; Sanchez, Yann; Brusque, Corinne

2015-01-01

Phone use while driving has become one of the priority issues in road safety, given that it may lead to decreased situation awareness and deteriorated driving performance. It has been suggested that drivers can regulate their exposure to secondary tasks and seek for compatibility of phone use and driving. Phone use strategies include the choice of driving situations with low demands and interruptions of the interaction when the context changes. Traffic light situations at urban intersections imply both a temptation to use the phone while waiting at the red traffic light and a potential threat due to the incompatibility of phone use and driving when the traffic light turns green. These two situations were targeted in a roadside observation study, with the aim to investigate the existence of a phone use strategy at the red traffic light and to test its effectiveness. N=124 phone users and a corresponding control group of non-users were observed. Strategic phone use behaviour was detected for visual-manual interactions, which are more likely to be initiated at the red traffic light and tend to be stopped before the vehicle moves off, while calls are less likely to be limited to the red traffic light situation. As an indicator of impaired situation awareness, delayed start was associated to phone use and in particular to visual-manual interactions, whether phone use was interrupted before moving off or not. Traffic light situations do not seem to allow effective application of phone use strategies, although drivers attempt to do so for the most demanding phone use mode. The underlying factors of phone use need to be studied so as to reduce the temptation of phone use and facilitate exposure regulation strategies. Copyright © 2014. Published by Elsevier Ltd.

Accuracy of quantitative visual soil assessment

Science.gov (United States)

van Leeuwen, Maricke; Heuvelink, Gerard; Stoorvogel, Jetse; Wallinga, Jakob; de Boer, Imke; van Dam, Jos; van Essen, Everhard; Moolenaar, Simon; Verhoeven, Frank; Stoof, Cathelijne

2016-04-01

Visual soil assessment (VSA) is a method to assess soil quality visually, when standing in the field. VSA is increasingly used by farmers, farm organisations and companies, because it is rapid and cost-effective, and because looking at soil provides understanding about soil functioning. Often VSA is regarded as subjective, so there is a need to verify VSA. Also, many VSAs have not been fine-tuned for contrasting soil types. This could lead to wrong interpretation of soil quality and soil functioning when contrasting sites are compared to each other. We wanted to assess accuracy of VSA, while taking into account soil type. The first objective was to test whether quantitative visual field observations, which form the basis in many VSAs, could be validated with standardized field or laboratory measurements. The second objective was to assess whether quantitative visual field observations are reproducible, when used by observers with contrasting backgrounds. For the validation study, we made quantitative visual observations at 26 cattle farms. Farms were located at sand, clay and peat soils in the North Friesian Woodlands, the Netherlands. Quantitative visual observations evaluated were grass cover, number of biopores, number of roots, soil colour, soil structure, number of earthworms, number of gley mottles and soil compaction. Linear regression analysis showed that four out of eight quantitative visual observations could be well validated with standardized field or laboratory measurements. The following quantitative visual observations correlated well with standardized field or laboratory measurements: grass cover with classified images of surface cover; number of roots with root dry weight; amount of large structure elements with mean weight diameter; and soil colour with soil organic matter content. Correlation coefficients were greater than 0.3, from which half of the correlations were significant. For the reproducibility study, a group of 9 soil scientists and 7

Simultaneous recording of electroretinogram and visual evoked response. Focal stimulation under direct observation.

Science.gov (United States)

Hirose, T; Miyake, Y; Hara, A

1977-07-01

A system has been tested that allows simultaneous recording of the retinal response (electroretinogram [ERG]) and the occipital response (visual evoked response [VER]) with focal photic stimulation of the retina under direct observation of the fundus. A helium-neon gas laser is used as a stimulus source. The laser is chopped either by a pen motor or a rotating disc. The laser is attached to a biomicroscope through which the examiner can observe the fundus of the subject during the entire recording session. The optically clear contact lens is made with a flat surface that neutralizes refraction due to the cornea, thereby allowing fundus observation by microscope. Two metal wires mounted inside and outside of the lens serve as the electrode for the ERG. Graticules consisting of concentric circles and radial lines are projected onto the subject's fundus, providing a pattern that the examiner can use to determine the exact location to be stimulated in the fundus. With proper adjustment of stimulus and background illumination, local ERG and VER can be recorded simultaneously by stimulating the macula.

Quantitative Assessment of Blood Pressure Measurement Accuracy and Variability from Visual Auscultation Method by Observers without Receiving Medical Training

Science.gov (United States)

Feng, Yong; Chen, Aiqing

2017-01-01

This study aimed to quantify blood pressure (BP) measurement accuracy and variability with different techniques. Thirty video clips of BP recordings from the BHS training database were converted to Korotkoff sound waveforms. Ten observers without receiving medical training were asked to determine BPs using (a) traditional manual auscultatory method and (b) visual auscultation method by visualizing the Korotkoff sound waveform, which was repeated three times on different days. The measurement error was calculated against the reference answers, and the measurement variability was calculated from the SD of the three repeats. Statistical analysis showed that, in comparison with the auscultatory method, visual method significantly reduced overall variability from 2.2 to 1.1 mmHg for SBP and from 1.9 to 0.9 mmHg for DBP (both p auscultation methods). In conclusion, the visual auscultation method had the ability to achieve an acceptable degree of BP measurement accuracy, with smaller variability in comparison with the traditional auscultatory method. PMID:29423405

Promoting Visualization Skills through Deconstruction Using Physical Models and a Visualization Activity Intervention

Science.gov (United States)

Schiltz, Holly Kristine

Visualization skills are important in learning chemistry, as these skills have been shown to correlate to high ability in problem solving. Students' understanding of visual information and their problem-solving processes may only ever be accessed indirectly: verbalization, gestures, drawings, etc. In this research, deconstruction of complex visual concepts was aligned with the promotion of students' verbalization of visualized ideas to teach students to solve complex visual tasks independently. All instructional tools and teaching methods were developed in accordance with the principles of the theoretical framework, the Modeling Theory of Learning: deconstruction of visual representations into model components, comparisons to reality, and recognition of students' their problemsolving strategies. Three physical model systems were designed to provide students with visual and tangible representations of chemical concepts. The Permanent Reflection Plane Demonstration provided visual indicators that students used to support or invalidate the presence of a reflection plane. The 3-D Coordinate Axis system provided an environment that allowed students to visualize and physically enact symmetry operations in a relevant molecular context. The Proper Rotation Axis system was designed to provide a physical and visual frame of reference to showcase multiple symmetry elements that students must identify in a molecular model. Focus groups of students taking Inorganic chemistry working with the physical model systems demonstrated difficulty documenting and verbalizing processes and descriptions of visual concepts. Frequently asked student questions were classified, but students also interacted with visual information through gestures and model manipulations. In an effort to characterize how much students used visualization during lecture or recitation, we developed observation rubrics to gather information about students' visualization artifacts and examined the effect instructors

Visual Information Communications International Conference

CERN Document Server

Nguyen, Quang Vinh; Zhang, Kang; VINCI'09

2010-01-01

Visual Information Communication is based on VINCI'09, The Visual Information Communications International Conference, September 2009 in Sydney, Australia. Topics covered include The Arts of Visual Layout, Presentation & Exploration, The Design of Visual Attributes, Symbols & Languages, Methods for Visual Analytics and Knowledge Discovery, Systems, Interfaces and Applications of Visualization, Methods for Multimedia Data Recognition & Processing. This cutting-edge book addresses the issues of knowledge discovery, end-user programming, modeling, rapid systems prototyping, education, and design activities. Visual Information Communications is an edited volume whose contributors include well-established researchers worldwide, from diverse disciplines including architects, artists, engineers, and scientists. Visual Information Communication is designed for a professional audience composed of practitioners and researchers working in the field of digital design and visual communications. This volume i...

An Empirical Study on Using Visual Embellishments in Visualization.

Science.gov (United States)

Borgo, R; Abdul-Rahman, A; Mohamed, F; Grant, P W; Reppa, I; Floridi, L; Chen, Min

2012-12-01

In written and spoken communications, figures of speech (e.g., metaphors and synecdoche) are often used as an aid to help convey abstract or less tangible concepts. However, the benefits of using rhetorical illustrations or embellishments in visualization have so far been inconclusive. In this work, we report an empirical study to evaluate hypotheses that visual embellishments may aid memorization, visual search and concept comprehension. One major departure from related experiments in the literature is that we make use of a dual-task methodology in our experiment. This design offers an abstraction of typical situations where viewers do not have their full attention focused on visualization (e.g., in meetings and lectures). The secondary task introduces "divided attention", and makes the effects of visual embellishments more observable. In addition, it also serves as additional masking in memory-based trials. The results of this study show that visual embellishments can help participants better remember the information depicted in visualization. On the other hand, visual embellishments can have a negative impact on the speed of visual search. The results show a complex pattern as to the benefits of visual embellishments in helping participants grasp key concepts from visualization.

Abnormal late visual responses and alpha oscillations in neurofibromatosis type 1: a link to visual and attention deficits

Science.gov (United States)

2014-01-01

Background Neurofibromatosis type 1 (NF1) affects several areas of cognitive function including visual processing and attention. We investigated the neural mechanisms underlying the visual deficits of children and adolescents with NF1 by studying visual evoked potentials (VEPs) and brain oscillations during visual stimulation and rest periods. Methods Electroencephalogram/event-related potential (EEG/ERP) responses were measured during visual processing (NF1 n = 17; controls n = 19) and idle periods with eyes closed and eyes open (NF1 n = 12; controls n = 14). Visual stimulation was chosen to bias activation of the three detection mechanisms: achromatic, red-green and blue-yellow. Results We found significant differences between the groups for late chromatic VEPs and a specific enhancement in the amplitude of the parieto-occipital alpha amplitude both during visual stimulation and idle periods. Alpha modulation and the negative influence of alpha oscillations in visual performance were found in both groups. Conclusions Our findings suggest abnormal later stages of visual processing and enhanced amplitude of alpha oscillations supporting the existence of deficits in basic sensory processing in NF1. Given the link between alpha oscillations, visual perception and attention, these results indicate a neural mechanism that might underlie the visual sensitivity deficits and increased lapses of attention observed in individuals with NF1. PMID:24559228

Time-varying spatial data integration and visualization: 4 Dimensions Environmental Observations Platform (4-DEOS)

Science.gov (United States)

Paciello, Rossana; Coviello, Irina; Filizzola, Carolina; Genzano, Nicola; Lisi, Mariano; Mazzeo, Giuseppe; Pergola, Nicola; Sileo, Giancanio; Tramutoli, Valerio

2014-05-01

In environmental studies the integration of heterogeneous and time-varying data, is a very common requirement for investigating and possibly visualize correlations among physical parameters underlying the dynamics of complex phenomena. Datasets used in such kind of applications has often different spatial and temporal resolutions. In some case superimposition of asynchronous layers is required. Traditionally the platforms used to perform spatio-temporal visual data analyses allow to overlay spatial data, managing the time using 'snapshot' data model, each stack of layers being labeled with different time. But this kind of architecture does not incorporate the temporal indexing neither the third spatial dimension which is usually given as an independent additional layer. Conversely, the full representation of a generic environmental parameter P(x,y,z,t) in the 4D space-time domain could allow to handle asynchronous datasets as well as less traditional data-products (e.g. vertical sections, punctual time-series, etc.) . In this paper we present the 4 Dimensions Environmental Observation Platform (4-DEOS), a system based on a web services architecture Client-Broker-Server. This platform is a new open source solution for both a timely access and an easy integration and visualization of heterogeneous (maps, vertical profiles or sections, punctual time series, etc.) asynchronous, geospatial products. The innovative aspect of the 4-DEOS system is that users can analyze data/products individually moving through time, having also the possibility to stop the display of some data/products and focus on other parameters for better studying their temporal evolution. This platform gives the opportunity to choose between two distinct display modes for time interval or for single instant. Users can choose to visualize data/products in two ways: i) showing each parameter in a dedicated window or ii) visualize all parameters overlapped in a single window. A sliding time bar, allows

Improving visual skills: II-remote assessment via Internet.

Science.gov (United States)

Powers, Maureen K; Grisham, J David; Wurm, Janice K; Wurm, William C

2009-02-01

Even though poor readers often have poor visual skills, such as binocular coordination and oculomotor control, students' visual skills are rarely assessed. Computer assessments have the potential to assist in identifying students whose visual skills are deficient. This study compared assessments made by an Internet-based computer orthoptics program with those of an on-site vision therapist. Students (N = 41) in grades 1 through 8, reading at least 2 levels below grade, were assessed for visual skill dysfunction (including binocular fusion and tracking ability) by a vision therapist at their school in Wisconsin. The therapist determined whether the student had adequate visual skills based on clinical and behavioral observations. A "remote" investigator located in California determined the adequacy of accommodative facility, tracking, and vergence skills in the same students, based on quantitative progress through the modules of an Internet-based computer orthoptics training program during 3 assessment sessions. The on-site therapist made 33 referrals for possible visual skills training (80%). The remote investigator made 25 referrals (61%), all of which were consistent with referrals made by the on-site therapist; thus, no false-positives occurred when using the remote assessment technique. The 8 additional referrals by the therapist were attributed to the ability to observe student behavior during assessment. Remote assessment of visual skills via an Internet orthoptics program may provide a simple means to detect visual skill problems experienced by poor readers.

Causes of visual impairment in children with low vision.

Science.gov (United States)

Shah, Mufarriq; Khan, Mirzaman; Khan, Muhammad Tariq; Khan, Mohammad Younas; Saeed, Nasir

2011-02-01

To determine the main causes of visual impairment in children with low vision. To assess the need of spectacles and low vision devices (LVDs) in children and to evaluate visual outcome after using their LVDs for far and near distance. Observational study. Khyber Institute of Ophthalmic Medical Sciences, Peshawar, Pakistan, from June 2006 to December 2007. The clinical record of 270 children with low vision age 4-16 years attending the Low Vision Clinic were included. All those children, aged 4-16 years, who had corrected visual acuity (VA) less than 6/18 in the better eye after medical or surgical treatment, were included in the study. WHO low vision criteria were used to classify into visually impaired, severe visually impaired and blind. Results were described as percentage frequencies. One hundred and eighty nine (70%) were males and 81 (30%) were females. The male to female ratio was 2.3:1. The main causes of visual impairment included nystagmus (15%), Stargardt's disease (14%), maculopathies (13%), myopic macular degeneration (11%) and oculocutaneous albinism (7%). The percentages of visually impaired, severe visually impaired and blind were 33.8%, 27.2% and 39.0% respectively. Spectacles were prescribed to 146 patients and telescopes were prescribed to 75 patients. Spectacles and telescope both were prescribed to 179 patients while Ocutech telescope was prescribed to 4 patients. Retinal diseases nystagmus and macular conditions were mainly responsible for low vision in children. Visually impaired children especially with hereditary/congenital ocular anomalies benefit from refraction and low vision services which facilitate vision enhancement and inclusive education.

Virtual reality visualization of accelerator magnets

International Nuclear Information System (INIS)

Huang, M.; Papka, M.; DeFanti, T.; Kettunen, L.

1995-01-01

The authors describe the use of the CAVE virtual reality visualization environment as an aid to the design of accelerator magnets. They have modeled an elliptical multipole wiggler magnet being designed for use at the Advanced Photon Source at Argonne National Laboratory. The CAVE environment allows the authors to explore and interact with the 3-D visualization of the magnet. Capabilities include changing the number of periods the magnet displayed, changing the icons used for displaying the magnetic field, and changing the current in the electromagnet and observing the effect on the magnetic field and particle beam trajectory through the field

Priming and the guidance by visual and categorical templates in visual search

Directory of Open Access Journals (Sweden)

Anna eWilschut

2014-02-01

Full Text Available Visual search is thought to be guided by top-down templates that are held in visual working memory. Previous studies have shown that a search-guiding template can be rapidly and strongly implemented from a visual cue, whereas templates are less effective when based on categorical cues. Direct visual priming from cue to target may underlie this difference. In two experiments we first asked observers to remember two possible target colors. A postcue then indicated which of the two would be the relevant color. The task was to locate a briefly presented and masked target of the cued color among irrelevant distractor items. Experiment 1 showed that overall search accuracy improved more rapidly on the basis of a direct visual postcue that carried the target color, compared to a neutral postcue that pointed to the memorized color. However, selectivity towards the target feature, i.e. the extent to which observers searched selectively among items of the cued versus uncued color, was found to be relatively unaffected by the presence of the visual signal. In Experiment 2 we compared search that was based on either visual or categorical information, but now controlled for direct visual priming. This resulted in no differences in overall performance nor selectivity. Altogether the results suggest that perceptual processing of visual search targets is facilitated by priming from visual cues, whereas attentional selectivity is enhanced by a working memory template that can formed from both visual and categorical input. Furthermore, if the priming is controlled for, categorical- and visual-based templates similarly enhance search guidance.

Priming and the guidance by visual and categorical templates in visual search.

Science.gov (United States)

Wilschut, Anna; Theeuwes, Jan; Olivers, Christian N L

2014-01-01

Visual search is thought to be guided by top-down templates that are held in visual working memory. Previous studies have shown that a search-guiding template can be rapidly and strongly implemented from a visual cue, whereas templates are less effective when based on categorical cues. Direct visual priming from cue to target may underlie this difference. In two experiments we first asked observers to remember two possible target colors. A postcue then indicated which of the two would be the relevant color. The task was to locate a briefly presented and masked target of the cued color among irrelevant distractor items. Experiment 1 showed that overall search accuracy improved more rapidly on the basis of a direct visual postcue that carried the target color, compared to a neutral postcue that pointed to the memorized color. However, selectivity toward the target feature, i.e., the extent to which observers searched selectively among items of the cued vs. uncued color, was found to be relatively unaffected by the presence of the visual signal. In Experiment 2 we compared search that was based on either visual or categorical information, but now controlled for direct visual priming. This resulted in no differences in overall performance nor selectivity. Altogether the results suggest that perceptual processing of visual search targets is facilitated by priming from visual cues, whereas attentional selectivity is enhanced by a working memory template that can formed from both visual and categorical input. Furthermore, if the priming is controlled for, categorical- and visual-based templates similarly enhance search guidance.

[Nursing Experience of Using Mirror Visual Feedback for a Schizophrenia Patient With Visual Hallucinations].

Science.gov (United States)

Lan, Shu-Ling; Chen, Yu-Chi; Chang, Hsiu-Ju

2018-06-01

The aim of this paper was to describe the nursing application of mirror visual feedback in a patient suffering from long-term visual hallucinations. The intervention period was from May 15th to October 19th, 2015. Using the five facets of psychiatric nursing assessment, several health problems were observed, including disturbed sensory perceptions (prominent visual hallucinations) and poor self-care (e.g. limited abilities to self-bathe and put on clothing). Furthermore, "caregiver role strain" due to the related intense care burden was noted. After building up a therapeutic interpersonal relationship, the technique of brain plasticity and mirror visual feedback were performed using multiple nursing care methods in order to help the patient suppress her visual hallucinations by enhancing a different visual stimulus. We also taught her how to cope with visual hallucinations in a proper manner. The frequency and content of visual hallucinations were recorded to evaluate the effects of management. The therapeutic plan was formulated together with the patient in order to boost her self-confidence, and a behavior contract was implemented in order to improve her personal hygiene. In addition, psychoeducation on disease-related topics was provided to the patient's family, and they were encouraged to attend relevant therapeutic activities. As a result, her family became less passive and negative and more engaged in and positive about her future. The crisis of "caregiver role strain" was successfully resolved. The current experience is hoped to serve as a model for enhancing communication and cooperation between family and staff in similar medical settings.

In multiple situational light settings, visual observation for skin colour assessment is comparable with colorimeter measurement.

Science.gov (United States)

Wright, C Y; Wilkes, M; du Plessis, J L; Reeder, A I; Albers, P N

2016-08-01

Finding inexpensive and reliable techniques for assessing skin colour is important, given that it is related to several adverse human health outcomes. Visual observation is considered a subjective approach assessment and, even when made by trained assessor, concern has been raised about the need for controlled lighting in the study venue. The aim of this study is to determine whether visual skin colour assessments correlate with objective skin colour measurements in study venues with different lighting types and configurations. Two trained investigators, with confirmed visual acuity, visually classified the inner, upper arm skin colour of 556 adults using Munsell(®) colour classifications converted to Individual Typology Angle (°ITA) values based on published data. Skin colour at the same anatomic site was also measured using a colorimeter. Each participant was assessed in one of 10 different buildings, each with a different study day. Munsell(®) -derived °ITA values were compared to colorimeter °ITA values for the full sample and by building/day. We found a strong positive, monotonic correlation between Munsell(®) derived °ITA values and colorimeter °ITA values for all participants (Spearman ρ = 0.8585, P colorimeter °ITA values were compared for participants assessed in the same building for all 10 buildings (Spearman ρ values ranged from 0.797 to 0.934, all correlations were statistically significant at P < 0.001). It is possible to visually assess individual skin colour in multiple situational lighting settings and retrieve results that are comparable with objective measurements of skin colour. This was true for individuals of varying population groups and skin pigmentation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Filling the Astronomical Void - A Visual Medium for a Visual Subject

Science.gov (United States)

Ryan, J.

1996-12-01

Astronomy is fundamentally a visual subject. The modern science of astronomy has at its foundation the ancient art of observing the sky visually. The visual elements of astronomy are arguably the most important. Every person in the entire world is affected by visually-observed astronomical phenomena such as the seasonal variations in daylight. However, misconceptions abound and the average person cannot recognize the simple signs in the sky that point to the direction, the hour and the season. Educators and astronomy popularizers widely lament that astronomy is not appreciated in our society. Yet, there is a remarkable dearth of popular literature for teaching the visual elements of astronomy. This is what I refer to as *the astronomical void.* Typical works use illustrations sparsely, relying most heavily on text-based descriptions of the visual astronomical phenomena. Such works leave significant inferential gaps to the inexperienced reader, who is unequipped for making astronomical observations. Thus, the astronomical void remains unfilled by much of the currently available literature. I therefore propose the introduction of a visually-oriented medium for teaching the visual elements of Astronomy. To this end, I have prepared a series of astronomy "comic strips" that are intended to fill the astronomical void. By giving the illustrations the central place, the comic strip medium permits the depiction of motion and other sequential activity, thus effectively representing astronomical phenomena. In addition to the practical advantages, the comic strip is a "user friendly" medium that is inviting and entertaining to a reader. At the present time, I am distributing a monthly comic strip entitled *Starman*, which appears in the newsletters of over 120 local astronomy organizations and on the web at http://www.cyberdrive.net/ starman. I hope to eventually publish a series of full-length books and believe that astronomical comic strips will help expand the perimeter of

Are Male Judokas with Visual Impairments Training Properly? Findings from an Observational Study

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Gutierrez-Santiago, Alfonso; Cancela, Jose M.; Zubiaur, Marta; Ayan, Carlos

2012-01-01

Introduction: One aim of the study was to describe the temporal structure of judo combat among male judokas with visual impairments. Another aim was to determine the possible differences between the judokas with visual impairments and sighted male judokas to determine whether judokas with visual impairments need specific training to achieve their…

Perception of co-speech gestures in aphasic patients: a visual exploration study during the observation of dyadic conversations.

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Preisig, Basil C; Eggenberger, Noëmi; Zito, Giuseppe; Vanbellingen, Tim; Schumacher, Rahel; Hopfner, Simone; Nyffeler, Thomas; Gutbrod, Klemens; Annoni, Jean-Marie; Bohlhalter, Stephan; Müri, René M

2015-03-01

Co-speech gestures are part of nonverbal communication during conversations. They either support the verbal message or provide the interlocutor with additional information. Furthermore, they prompt as nonverbal cues the cooperative process of turn taking. In the present study, we investigated the influence of co-speech gestures on the perception of dyadic dialogue in aphasic patients. In particular, we analysed the impact of co-speech gestures on gaze direction (towards speaker or listener) and fixation of body parts. We hypothesized that aphasic patients, who are restricted in verbal comprehension, adapt their visual exploration strategies. Sixteen aphasic patients and 23 healthy control subjects participated in the study. Visual exploration behaviour was measured by means of a contact-free infrared eye-tracker while subjects were watching videos depicting spontaneous dialogues between two individuals. Cumulative fixation duration and mean fixation duration were calculated for the factors co-speech gesture (present and absent), gaze direction (to the speaker or to the listener), and region of interest (ROI), including hands, face, and body. Both aphasic patients and healthy controls mainly fixated the speaker's face. We found a significant co-speech gesture × ROI interaction, indicating that the presence of a co-speech gesture encouraged subjects to look at the speaker. Further, there was a significant gaze direction × ROI × group interaction revealing that aphasic patients showed reduced cumulative fixation duration on the speaker's face compared to healthy controls. Co-speech gestures guide the observer's attention towards the speaker, the source of semantic input. It is discussed whether an underlying semantic processing deficit or a deficit to integrate audio-visual information may cause aphasic patients to explore less the speaker's face. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reappraising the functional implications of the primate visual anatomical hierarchy.

Science.gov (United States)

Hegdé, Jay; Felleman, Daniel J

2007-10-01

The primate visual system has been shown to be organized into an anatomical hierarchy by the application of a few principled criteria. It has been widely assumed that cortical visual processing is also hierarchical, with the anatomical hierarchy providing a defined substrate for clear levels of hierarchical function. A large body of empirical evidence seemed to support this assumption, including the general observations that functional properties of visual neurons grow progressively more complex at progressively higher levels of the anatomical hierarchy. However, a growing body of evidence, including recent direct experimental comparisons of functional properties at two or more levels of the anatomical hierarchy, indicates that visual processing neither is hierarchical nor parallels the anatomical hierarchy. Recent results also indicate that some of the pathways of visual information flow are not hierarchical, so that the anatomical hierarchy cannot be taken as a strict flowchart of visual information either. Thus, while the sustaining strength of the notion of hierarchical processing may be that it is rather simple, its fatal flaw is that it is overly simplistic.

Constructing visual representations

DEFF Research Database (Denmark)

Huron, Samuel; Jansen, Yvonne; Carpendale, Sheelagh

2014-01-01

tangible building blocks. We learned that all participants, most of whom had little experience in visualization authoring, were readily able to create and talk about their own visualizations. Based on our observations, we discuss participants’ actions during the development of their visual representations......The accessibility of infovis authoring tools to a wide audience has been identified as a major research challenge. A key task in the authoring process is the development of visual mappings. While the infovis community has long been deeply interested in finding effective visual mappings......, comparatively little attention has been placed on how people construct visual mappings. In this paper, we present the results of a study designed to shed light on how people transform data into visual representations. We asked people to create, update and explain their own information visualizations using only...

Data visualization methods, data visualization devices, data visualization apparatuses, and articles of manufacture

Science.gov (United States)

Turner, Alan E.; Crow, Vernon L.; Payne, Deborah A.; Hetzler, Elizabeth G.; Cook, Kristin A.; Cowley, Wendy E.

2015-06-30

Data visualization methods, data visualization devices, data visualization apparatuses, and articles of manufacture are described according to some aspects. In one aspect, a data visualization method includes accessing a plurality of initial documents at a first moment in time, first processing the initial documents providing processed initial documents, first identifying a plurality of first associations of the initial documents using the processed initial documents, generating a first visualization depicting the first associations, accessing a plurality of additional documents at a second moment in time after the first moment in time, second processing the additional documents providing processed additional documents, second identifying a plurality of second associations of the additional documents and at least some of the initial documents, wherein the second identifying comprises identifying using the processed initial documents and the processed additional documents, and generating a second visualization depicting the second associations.

A workflow for the 3D visualization of meteorological data

Science.gov (United States)

Helbig, Carolin; Rink, Karsten

2014-05-01

In the future, climate change will strongly influence our environment and living conditions. To predict possible changes, climate models that include basic and process conditions have been developed and big data sets are produced as a result of simulations. The combination of various variables of climate models with spatial data from different sources helps to identify correlations and to study key processes. For our case study we use results of the weather research and forecasting (WRF) model of two regions at different scales that include various landscapes in Northern Central Europe and Baden-Württemberg. We visualize these simulation results in combination with observation data and geographic data, such as river networks, to evaluate processes and analyze if the model represents the atmospheric system sufficiently. For this purpose, a continuous workflow that leads from the integration of heterogeneous raw data to visualization using open source software (e.g. OpenGeoSys Data Explorer, ParaView) is developed. These visualizations can be displayed on a desktop computer or in an interactive virtual reality environment. We established a concept that includes recommended 3D representations and a color scheme for the variables of the data based on existing guidelines and established traditions in the specific domain. To examine changes over time in observation and simulation data, we added the temporal dimension to the visualization. In a first step of the analysis, the visualizations are used to get an overview of the data and detect areas of interest such as regions of convection or wind turbulences. Then, subsets of data sets are extracted and the included variables can be examined in detail. An evaluation by experts from the domains of visualization and atmospheric sciences establish if they are self-explanatory and clearly arranged. These easy-to-understand visualizations of complex data sets are the basis for scientific communication. In addition, they have

Data visualization a guide to visual storytelling for libraries

CERN Document Server

2016-01-01

Data Visualization: A Guide to Visual Storytelling for Libraries is a practical guide to the skills and tools needed to create beautiful and meaningful visual stories through data visualization. Learn how to sift through complex datasets to better understand a variety of metrics, such as trends in user behavior and electronic resource usage, return on investment (ROI) and impact metrics, and learning and reference analytics. Sections include: .Identifying and interpreting datasets for visualization .Tools and technologies for creating meaningful visualizations .Case studies in data visualization and dashboards Understanding and communicating trends from your organization s data is essential. Whether you are looking to make more informed decisions by visualizing organizational data, or to tell the story of your library s impact on your community, this book will give you the tools to make it happen."

Visual Memories Bypass Normalization.

Science.gov (United States)

Bloem, Ilona M; Watanabe, Yurika L; Kibbe, Melissa M; Ling, Sam

2018-05-01

How distinct are visual memory representations from visual perception? Although evidence suggests that briefly remembered stimuli are represented within early visual cortices, the degree to which these memory traces resemble true visual representations remains something of a mystery. Here, we tested whether both visual memory and perception succumb to a seemingly ubiquitous neural computation: normalization. Observers were asked to remember the contrast of visual stimuli, which were pitted against each other to promote normalization either in perception or in visual memory. Our results revealed robust normalization between visual representations in perception, yet no signature of normalization occurring between working memory stores-neither between representations in memory nor between memory representations and visual inputs. These results provide unique insight into the nature of visual memory representations, illustrating that visual memory representations follow a different set of computational rules, bypassing normalization, a canonical visual computation.

Halftone visual cryptography.

Science.gov (United States)

Zhou, Zhi; Arce, Gonzalo R; Di Crescenzo, Giovanni

2006-08-01

Visual cryptography encodes a secret binary image (SI) into n shares of random binary patterns. If the shares are xeroxed onto transparencies, the secret image can be visually decoded by superimposing a qualified subset of transparencies, but no secret information can be obtained from the superposition of a forbidden subset. The binary patterns of the n shares, however, have no visual meaning and hinder the objectives of visual cryptography. Extended visual cryptography [1] was proposed recently to construct meaningful binary images as shares using hypergraph colourings, but the visual quality is poor. In this paper, a novel technique named halftone visual cryptography is proposed to achieve visual cryptography via halftoning. Based on the blue-noise dithering principles, the proposed method utilizes the void and cluster algorithm [2] to encode a secret binary image into n halftone shares (images) carrying significant visual information. The simulation shows that the visual quality of the obtained halftone shares are observably better than that attained by any available visual cryptography method known to date.

Visual search elicits the electrophysiological marker of visual working memory.

Directory of Open Access Journals (Sweden)

Stephen M Emrich

Full Text Available BACKGROUND: Although limited in capacity, visual working memory (VWM plays an important role in many aspects of visually-guided behavior. Recent experiments have demonstrated an electrophysiological marker of VWM encoding and maintenance, the contralateral delay activity (CDA, which has been shown in multiple tasks that have both explicit and implicit memory demands. Here, we investigate whether the CDA is evident during visual search, a thoroughly-researched task that is a hallmark of visual attention but has no explicit memory requirements. METHODOLOGY/PRINCIPAL FINDINGS: The results demonstrate that the CDA is present during a lateralized search task, and that it is similar in amplitude to the CDA observed in a change-detection task, but peaks slightly later. The changes in CDA amplitude during search were strongly correlated with VWM capacity, as well as with search efficiency. These results were paralleled by behavioral findings showing a strong correlation between VWM capacity and search efficiency. CONCLUSIONS/SIGNIFICANCE: We conclude that the activity observed during visual search was generated by the same neural resources that subserve VWM, and that this activity reflects the maintenance of previously searched distractors.

Perceptual learning improves contrast sensitivity, visual acuity, and foveal crowding in amblyopia.

Science.gov (United States)

Barollo, Michele; Contemori, Giulio; Battaglini, Luca; Pavan, Andrea; Casco, Clara

2017-01-01

Amblyopic observers present abnormal spatial interactions between a low-contrast sinusoidal target and high-contrast collinear flankers. It has been demonstrated that perceptual learning (PL) can modulate these low-level lateral interactions, resulting in improved visual acuity and contrast sensitivity. We measured the extent and duration of generalization effects to various spatial tasks (i.e., visual acuity, Vernier acuity, and foveal crowding) through PL on the target's contrast detection. Amblyopic observers were trained on a contrast-detection task for a central target (i.e., a Gabor patch) flanked above and below by two high-contrast Gabor patches. The pre- and post-learning tasks included lateral interactions at different target-to-flankers separations (i.e., 2, 3, 4, 8λ) and included a range of spatial frequencies and stimulus durations as well as visual acuity, Vernier acuity, contrast-sensitivity function, and foveal crowding. The results showed that perceptual training reduced the target's contrast-detection thresholds more for the longest target-to-flanker separation (i.e., 8λ). We also found generalization of PL to different stimuli and tasks: contrast sensitivity for both trained and untrained spatial frequencies, visual acuity for Sloan letters, and foveal crowding, and partially for Vernier acuity. Follow-ups after 5-7 months showed not only complete maintenance of PL effects on visual acuity and contrast sensitivity function but also further improvement in these tasks. These results suggest that PL improves facilitatory lateral interactions in amblyopic observers, which usually extend over larger separations than in typical foveal vision. The improvement in these basic visual spatial operations leads to a more efficient capability of performing spatial tasks involving high levels of visual processing, possibly due to the refinement of bottom-up and top-down networks of visual areas.

Augmented Visual Experience of Simulated Solar Phenomena

Science.gov (United States)

Tucker, A. O., IV; Berardino, R. A.; Hahne, D.; Schreurs, B.; Fox, N. J.; Raouafi, N.

2017-12-01

The Parker Solar Probe (PSP) mission will explore the Sun's corona, studying solar wind, flares and coronal mass ejections. The effects of these phenomena can impact the technology that we use in ways that are not readily apparent, including affecting satellite communications and power grids. Determining the structure and dynamics of corona magnetic fields, tracing the flow of energy that heats the corona, and exploring dusty plasma near the Sun to understand its influence on solar wind and energetic particle formation requires a suite of sensors on board the PSP spacecraft that are engineered to observe specific phenomena. Using models of these sensors and simulated observational data, we can visualize what the PSP spacecraft will "see" during its multiple passes around the Sun. Augmented reality (AR) technologies enable convenient user access to massive data sets. We are developing an application that allows users to experience environmental data from the point of view of the PSP spacecraft in AR using the Microsoft HoloLens. Observational data, including imagery, magnetism, temperature, and density are visualized in 4D within the user's immediate environment. Our application provides an educational tool for comprehending the complex relationships of observational data, which aids in our understanding of the Sun.

Mengamati Aspek-Aspek Visual Pertunjukan Tari Sebagai Pengayaan Kajian Senirupa

Directory of Open Access Journals (Sweden)

Anis Sujana

2007-08-01

Full Text Available According to the medium, arts can be classified into the art of visual, the art of hearing, and the art of words. Those included in the art of visual are dance and fine art, in the art of hearing is music and in the art of words is poetry. This paper describes one of the art of the visual—dance, which use human body and its movement as a medium of expression. Fact shows that a dance performance exists due to the involvement of supporting elements such as visual disposition. Certain dances limit themselves to the supporting elements of costumes, make-up, property (tools and musical instruments; others equip with stages, decorations, and lightings. Traditional dances—in particular—extensively equip themselves with supporting elements to show its characteristics. Thus, since dance requires the supporting element of visuals, it is reasonable to observe it as similar to the way we observe the object of fine art. The scope of observation for the supporting elements of dance performance may cover the whole visual events or just merely one of the scenes. Therefore, a contextual knowledge of both inside and outside can be fully grasped to form the background of the dance performance.

Perceptions Concerning Visual Culture Dialogues of Visual Art Pre-Service Teachers

Science.gov (United States)

Mamur, Nuray

2012-01-01

The visual art which is commented by the visual art teachers to help processing of the visual culture is important. In this study it is tried to describe the effect of visual culture based on the usual aesthetic experiences to be included in the learning process art education. The action research design, which is a qualitative study, is conducted…

Data visualization

CERN Document Server

Azzam, Tarek

2013-01-01

Do you communicate data and information to stakeholders? In Part 1, we introduce recent developments in the quantitative and qualitative data visualization field and provide a historical perspective on data visualization, its potential role in evaluation practice, and future directions. Part 2 delivers concrete suggestions for optimally using data visualization in evaluation, as well as suggestions for best practices in data visualization design. It focuses on specific quantitative and qualitative data visualization approaches that include data dashboards, graphic recording, and geographic information systems (GIS). Readers will get a step-by-step process for designing an effective data dashboard system for programs and organizations, and various suggestions to improve their utility.

Screening methods for post-stroke visual impairment: a systematic review.

Science.gov (United States)

Hanna, Kerry Louise; Hepworth, Lauren Rachel; Rowe, Fiona

2017-12-01

To provide a systematic overview of the various tools available to screen for post-stroke visual impairment. A review of the literature was conducted including randomised controlled trials, controlled trials, cohort studies, observational studies, systematic reviews and retrospective medical note reviews. All languages were included and translation was obtained. Participants included adults ≥18 years old diagnosed with a visual impairment as a direct cause of a stroke. We searched a broad range of scholarly online resources and hand-searched articles registers of published, unpublished and on-going trials. Search terms included a variety of MESH terms and alternatives in relation to stroke and visual conditions. Study selection was performed by two authors independently. The quality of the evidence and risk of bias were assessed using the STROBE, GRACE and PRISMA statements. A total of 25 articles (n = 2924) were included in this review. Articles appraised reported on tools screening solely for visual impairments or for general post-stroke disabilities inclusive of vision. The majority of identified tools screen for visual perception including visual neglect (VN), with few screening for visual acuity (VA), visual field (VF) loss or ocular motility (OM) defects. Six articles reported on nine screening tools which combined visual screening assessment alongside screening for general stroke disabilities. Of these, three included screening for VA; three screened for VF loss; three screened for OM defects and all screened for VN. Two tools screened for all visual impairments. A further 19 articles were found which reported on individual vision screening tests in stroke populations; two for VF loss; 11 for VN and six for other visual perceptual defects. Most tools cannot accurately account for those with aphasia or communicative deficits, which are common problems following a stroke. There is currently no standardised visual screening tool which can accurately

Characterizing the effects of feature salience and top-down attention in the early visual system.

Science.gov (United States)

Poltoratski, Sonia; Ling, Sam; McCormack, Devin; Tong, Frank

2017-07-01

The visual system employs a sophisticated balance of attentional mechanisms: salient stimuli are prioritized for visual processing, yet observers can also ignore such stimuli when their goals require directing attention elsewhere. A powerful determinant of visual salience is local feature contrast: if a local region differs from its immediate surround along one or more feature dimensions, it will appear more salient. We used high-resolution functional MRI (fMRI) at 7T to characterize the modulatory effects of bottom-up salience and top-down voluntary attention within multiple sites along the early visual pathway, including visual areas V1-V4 and the lateral geniculate nucleus (LGN). Observers viewed arrays of spatially distributed gratings, where one of the gratings immediately to the left or right of fixation differed from all other items in orientation or motion direction, making it salient. To investigate the effects of directed attention, observers were cued to attend to the grating to the left or right of fixation, which was either salient or nonsalient. Results revealed reliable additive effects of top-down attention and stimulus-driven salience throughout visual areas V1-hV4. In comparison, the LGN exhibited significant attentional enhancement but was not reliably modulated by orientation- or motion-defined salience. Our findings indicate that top-down effects of spatial attention can influence visual processing at the earliest possible site along the visual pathway, including the LGN, whereas the processing of orientation- and motion-driven salience primarily involves feature-selective interactions that take place in early cortical visual areas. NEW & NOTEWORTHY While spatial attention allows for specific, goal-driven enhancement of stimuli, salient items outside of the current focus of attention must also be prioritized. We used 7T fMRI to compare salience and spatial attentional enhancement along the early visual hierarchy. We report additive effects of

Relating Standardized Visual Perception Measures to Simulator Visual System Performance

Science.gov (United States)

Kaiser, Mary K.; Sweet, Barbara T.

2013-01-01

Human vision is quantified through the use of standardized clinical vision measurements. These measurements typically include visual acuity (near and far), contrast sensitivity, color vision, stereopsis (a.k.a. stereo acuity), and visual field periphery. Simulator visual system performance is specified in terms such as brightness, contrast, color depth, color gamut, gamma, resolution, and field-of-view. How do these simulator performance characteristics relate to the perceptual experience of the pilot in the simulator? In this paper, visual acuity and contrast sensitivity will be related to simulator visual system resolution, contrast, and dynamic range; similarly, color vision will be related to color depth/color gamut. Finally, we will consider how some characteristics of human vision not typically included in current clinical assessments could be used to better inform simulator requirements (e.g., relating dynamic characteristics of human vision to update rate and other temporal display characteristics).

How Do Observer's Responses Affect Visual Long-Term Memory?

Science.gov (United States)

Makovski, Tal; Jiang, Yuhong V.; Swallow, Khena M.

2013-01-01

How does responding to an object affect explicit memory for visual information? The close theoretical relationship between action and perception suggests that items that require a response should be better remembered than items that require no response. However, conclusive evidence for this claim is lacking, as semantic coherence, category size,…

Visual perception and radiographic interpretation

International Nuclear Information System (INIS)

Papageorges, M.

1998-01-01

Although interpretation errors are common in radiology, their causes are still debated. Perceptual mechanisms appear to be responsible for a large proportion of mistakes made by both neophytes and trained radiologists. Erroneous perception of familiar contours can be triggered by unrelated opacities. Conversely, visual information cannot induce a specific perception if the observer is not familiar with the concept represented or its radiographicappearance. Additionally, the area of acute vision is smaller than is commonly recognized. Other factors, such as the attitude, beliefs,.: preconceptions, and expectations of the viewer, can affect what he or she ''sees'' whenviewing any object, including a radiograph. Familiarity with perceptual mechanisms and the limitations of the visual system as well as multiple readings may be necessary to reduce interpretation errors

Observation of mass loss in R CrB during the visual light minimum

International Nuclear Information System (INIS)

Kameswara Rao, N.

1981-01-01

Visual light minima of R CrB stars are thought to be caused by the formation of circumstellar dust. It has been observed at the time of the light minimum that there is difference in the reddening between the descending and the rising branches of the light curves. The extinction during the descending branch tends to be neutral with not much of colour change, while there occurs redder colours during the recovery part of the light curve (Forrest 1974). It is probable that the gas causing the broad emission lines with Ne approximately 5 x 10 11 cm -3 also produces the neutral extinction due to electron scattering. An extinction of 4.5 mag can result if this region is assumed to extend to 2R. (Auth.)

A functional magnetic resonance imaging investigation of visual hallucinations in the human striate cortex.

Science.gov (United States)

Abid, Hina; Ahmad, Fayyaz; Lee, Soo Y; Park, Hyun W; Im, Dongmi; Ahmad, Iftikhar; Chaudhary, Safee U

2016-11-29

Human beings frequently experience fear, phobia, migraine and hallucinations, however, the cerebral mechanisms underpinning these conditions remain poorly understood. Towards this goal, in this work, we aim to correlate the human ocular perceptions with visual hallucinations, and map them to their cerebral origins. An fMRI study was performed to examine the visual cortical areas including the striate, parastriate and peristriate cortex in the occipital lobe of the human brain. 24 healthy subjects were enrolled and four visual patterns including hallucination circle (HCC), hallucination fan (HCF), retinotopy circle (RTC) and retinotopy cross (RTX) were used towards registering their impact in the aforementioned visual related areas. One-way analysis of variance was used to evaluate the significance of difference between induced activations. Multinomial regression and and K-means were used to cluster activation patterns in visual areas of the brain. Significant activations were observed in the visual cortex as a result of stimulus presentation. The responses induced by visual stimuli were resolved to Brodmann areas 17, 18 and 19. Activation data clustered into independent and mutually exclusive clusters with HCC registering higher activations as compared to HCF, RTC and RTX. We conclude that small circular objects, in rotation, tend to leave greater hallucinating impressions in the visual region. The similarity between observed activation patterns and those reported in conditions such as epilepsy and visual hallucinations can help elucidate the cortical mechanisms underlying these conditions. Trial Registration 1121_GWJUNG.

Human fMRI reveals that delayed action re-recruits visual perception.

Science.gov (United States)

Singhal, Anthony; Monaco, Simona; Kaufman, Liam D; Culham, Jody C

2013-01-01

Behavioral and neuropsychological research suggests that delayed actions rely on different neural substrates than immediate actions; however, the specific brain areas implicated in the two types of actions remain unknown. We used functional magnetic resonance imaging (fMRI) to measure human brain activation during delayed grasping and reaching. Specifically, we examined activation during visual stimulation and action execution separated by a 18-s delay interval in which subjects had to remember an intended action toward the remembered object. The long delay interval enabled us to unambiguously distinguish visual, memory-related, and action responses. Most strikingly, we observed reactivation of the lateral occipital complex (LOC), a ventral-stream area implicated in visual object recognition, and early visual cortex (EVC) at the time of action. Importantly this reactivation was observed even though participants remained in complete darkness with no visual stimulation at the time of the action. Moreover, within EVC, higher activation was observed for grasping than reaching during both vision and action execution. Areas in the dorsal visual stream were activated during action execution as expected and, for some, also during vision. Several areas, including the anterior intraparietal sulcus (aIPS), dorsal premotor cortex (PMd), primary motor cortex (M1) and the supplementary motor area (SMA), showed sustained activation during the delay phase. We propose that during delayed actions, dorsal-stream areas plan and maintain coarse action goals; however, at the time of execution, motor programming requires re-recruitment of detailed visual information about the object through reactivation of (1) ventral-stream areas involved in object perception and (2) early visual areas that contain richly detailed visual representations, particularly for grasping.

Human fMRI reveals that delayed action re-recruits visual perception.

Directory of Open Access Journals (Sweden)

Anthony Singhal

Full Text Available Behavioral and neuropsychological research suggests that delayed actions rely on different neural substrates than immediate actions; however, the specific brain areas implicated in the two types of actions remain unknown. We used functional magnetic resonance imaging (fMRI to measure human brain activation during delayed grasping and reaching. Specifically, we examined activation during visual stimulation and action execution separated by a 18-s delay interval in which subjects had to remember an intended action toward the remembered object. The long delay interval enabled us to unambiguously distinguish visual, memory-related, and action responses. Most strikingly, we observed reactivation of the lateral occipital complex (LOC, a ventral-stream area implicated in visual object recognition, and early visual cortex (EVC at the time of action. Importantly this reactivation was observed even though participants remained in complete darkness with no visual stimulation at the time of the action. Moreover, within EVC, higher activation was observed for grasping than reaching during both vision and action execution. Areas in the dorsal visual stream were activated during action execution as expected and, for some, also during vision. Several areas, including the anterior intraparietal sulcus (aIPS, dorsal premotor cortex (PMd, primary motor cortex (M1 and the supplementary motor area (SMA, showed sustained activation during the delay phase. We propose that during delayed actions, dorsal-stream areas plan and maintain coarse action goals; however, at the time of execution, motor programming requires re-recruitment of detailed visual information about the object through reactivation of (1 ventral-stream areas involved in object perception and (2 early visual areas that contain richly detailed visual representations, particularly for grasping.

Prism therapy and visual rehabilitation in homonymous visual field loss.

LENUS (Irish Health Repository)

O'Neill, Evelyn C

2012-02-01

PURPOSE: Homonymous visual field defects (HVFD) are common and frequently occur after cerebrovascular accidents. They significantly impair visual function and cause disability particularly with regard to visual exploration. The purpose of this study was to assess a novel interventional treatment of monocular prism therapy on visual functioning in patients with HVFD of varied etiology using vision targeted, health-related quality of life (QOL) questionnaires. Our secondary aim was to confirm monocular and binocular visual field expansion pre- and posttreatment. METHODS: Twelve patients with acquired, documented HVFD were eligible to be included. All patients underwent specific vision-targeted, health-related QOL questionnaire and monocular and binocular Goldmann perimetry before commencing prism therapy. Patients were fitted with monocular prisms on the side of the HVFD with the base-in the direction of the field defect creating a peripheral optical exotropia and field expansion. After the treatment period, QOL questionnaires and perimetry were repeated. RESULTS: Twelve patients were included in the treatment group, 10 of whom were included in data analysis. Overall, there was significant improvement within multiple vision-related, QOL functioning parameters, specifically within the domains of general health (p < 0.01), general vision (p < 0.05), distance vision (p < 0.01), peripheral vision (p < 0.05), role difficulties (p < 0.05), dependency (p < 0.05), and social functioning (p < 0.05). Visual field expansion was shown when measured monocularly and binocularly during the study period in comparison with pretreatment baselines. CONCLUSIONS: Patients with HVFD demonstrate decreased QOL. Monocular sector prisms can improve the QOL and expand the visual field in these patients.

The Use of Visual Arts as a Window to Diagnosing Medical Pathologies.

Science.gov (United States)

Bramstedt, Katrina A

2016-08-01

Observation is a key step preceding diagnosis, prognostication, and treatment. Careful patient observation is a skill that is learned but rarely explicitly taught. Furthermore, proper clinical observation requires more than a glance; it requires attention to detail. In medical school, the art of learning to look can be taught using the medical humanities and especially visual arts such as paintings and film. Research shows that such training improves not only observation skills but also teamwork, listening skills, and reflective and analytical thinking. Overall, the use of visual arts in medical school curricula can build visual literacy: the capacity to identify and analyze facial features, emotions, and general bodily presentations, including contextual features such as clothing, hair, and body art. With the ability to formulate and convey a detailed "picture" of the patient, clinicians can integrate aesthetic and clinical knowledge, helping facilitate the diagnosing of medical pathologies. © 2016 American Medical Association. All Rights Reserved.

iStimulation: Apple iPad Use with Children Who Are Visually Impaired, Including Those with Multiple Disabilities

Science.gov (United States)

Campaña, Laura V.; Ouimet, Donald A.

2015-01-01

Since its creation in the early 1980s, Light Box, a product developed by the American Printing House for the Blind (APH) that is designed for working on functional vision tasks with children who have visual impairments or multiple disabilities, has been an effective tool to help teach children with visual impairments to locate and track items…

Visualizing the Impacts of Movement Infrastructures on Social Inclusion: Graph-Based Methods for Observing Community Formations in Contrasting Geographic Contexts

Directory of Open Access Journals (Sweden)

Jamie O'Brien

2017-12-01

Full Text Available In this article we describe some innovative methods for observing the possible impacts of roads, junctions and pathways (movement infrastructures, on community life in terms of their affordances and hindrances for social connectivity. In seeking to observe these impacts, we combined a range of visualization research methods, based on qualitative points-data mapping, graphic representation and urban morphological analysis at local and global geographic scales. Our overall aim in this study was to develop exploratory methods for combining and visualizing various kinds of data that relate to urban community formations in contrasting urban contexts. We focused our enquiry on the perspectives of adolescents in two urban contexts: Liverpool, UK, and Medellín, Colombia. While they contrast in their geo-political and cultural characteristics, these two cities each present polarized socio-economic inequalities across distinctive spatial patterns. We found that adolescents in these cities offer generally localized, pedestrian perspectives of their local areas, and unique insights into the opportunities and challenges for place-making in their local community spaces. We gathered the communities’ local perspectives through map-making workshops, in which participants used given iconographic symbols to select and weight the social and structural assets that they deemed to be significant features of their community spaces. We then sampled and visualized these selective points data to observe ways in which local community assets relate to infrastructural affordances for movement (in terms of network integration. This analysis was based on the theory and method of Space Syntax, which provides a model of affordances for movement across the urban network over various scales of network configuration. In particular, we sought to determine how city-scale movement infrastructures interact with local-scale infrastructures, and to develop methods for observing ways

Visualization of diversity in large multivariate data sets.

Science.gov (United States)

Pham, Tuan; Hess, Rob; Ju, Crystal; Zhang, Eugene; Metoyer, Ronald

2010-01-01

Understanding the diversity of a set of multivariate objects is an important problem in many domains, including ecology, college admissions, investing, machine learning, and others. However, to date, very little work has been done to help users achieve this kind of understanding. Visual representation is especially appealing for this task because it offers the potential to allow users to efficiently observe the objects of interest in a direct and holistic way. Thus, in this paper, we attempt to formalize the problem of visualizing the diversity of a large (more than 1000 objects), multivariate (more than 5 attributes) data set as one worth deeper investigation by the information visualization community. In doing so, we contribute a precise definition of diversity, a set of requirements for diversity visualizations based on this definition, and a formal user study design intended to evaluate the capacity of a visual representation for communicating diversity information. Our primary contribution, however, is a visual representation, called the Diversity Map, for visualizing diversity. An evaluation of the Diversity Map using our study design shows that users can judge elements of diversity consistently and as or more accurately than when using the only other representation specifically designed to visualize diversity.

Learning invariance from natural images inspired by observations in the primary visual cortex.

Science.gov (United States)

Teichmann, Michael; Wiltschut, Jan; Hamker, Fred

2012-05-01

The human visual system has the remarkable ability to largely recognize objects invariant of their position, rotation, and scale. A good interpretation of neurobiological findings involves a computational model that simulates signal processing of the visual cortex. In part, this is likely achieved step by step from early to late areas of visual perception. While several algorithms have been proposed for learning feature detectors, only few studies at hand cover the issue of biologically plausible learning of such invariance. In this study, a set of Hebbian learning rules based on calcium dynamics and homeostatic regulations of single neurons is proposed. Their performance is verified within a simple model of the primary visual cortex to learn so-called complex cells, based on a sequence of static images. As a result, the learned complex-cell responses are largely invariant to phase and position.

A Case Report on Somatoform Disorder: Colorful Visual Hallucinations

Directory of Open Access Journals (Sweden)

Susan Afghah

2013-04-01

Full Text Available Objectives: To report a case of somatoform disorder (not otherwise specified-NOS. Methods: The patient was an eight-year-old boy who complained of anxiety and seeing visual hallucinations of colorful shapes. He was administered ant migraine and antiepileptic drugs. However, no changes were observed. Psychotherapy was started, as well as fluoxetine (20 mg per day. Initial assessments included a behavioral interview, charting of daily activities, and recording visual hallucinations with a description of the patient’s emotional and situational condition during the hallucinations. Results: The patient’s visual hallucinations disappeared completely after two months of treatment. Discussion: Somatoform disorders may respond well to a combination of behavioral therapy and antidepressant medication.

Observação do desenvolvimento de linguagem e funções auditiva e visual em lactentes Observation of language, visual and hearing function development in infants

Directory of Open Access Journals (Sweden)

Maria Cecília Marconi Pinheiro Lima

2004-02-01

Full Text Available OBJETIVO: Investigar o desenvolvimento da linguagem e das funções auditiva e visual em lactentes de creche, a partir da avaliação realizada por educadores. MÉTODOS: Foram avaliados 115 lactentes, nos anos de 1998 a 2001, usuários de uma creche da área da saúde de uma universidade do Estado de São Paulo. Foi utilizado o "Protocolo da Observação do Desenvolvimento de Linguagem e das Funções Auditiva e Visual", com 39 provas no total, para a avaliação dos lactentes de 3 até 12 meses de idade. A aplicação desse Protocolo foi feita pelas educadoras da creche, devidamente treinadas. Utilizou-se o teste de Qui-quadrado ou Exato de Fisher. O nível de significância adotado foi de 5%. RESULTADOS: Os lactentes apresentaram um padrão diferente no desenvolvimento da linguagem quanto ao início do balbucio e das primeiras palavras, bem como na função visual, quanto à imitação e uso de jogos gestuais e de seguir ordem com uso de gestos. CONCLUSÕES: O ambiente creche propicia condições para um outro padrão de desenvolvimento de linguagem e das funções auditiva e visual. Ações de prevenção na creche devem integrar as áreas de saúde e educação num objetivo comum.OBJECTIVE: To investigate language, visual and hearing function development among infants in a day-care center based on educators' assessments. METHODS: One hundred and fifteen infants who attended a day-care center at one university of the São Paulo State, Brazil, were assessed during the period between 1998 and 2001. The "Protocol for Observation of Language, Visual and Hearing Function Development," containing a total of 39 standardized tests, was utilized to assess infants from three to twelve months old. The protocol was applied by trained educators, members of the day-care center staff. Statistical analysis was carried out using Chi-square test or Fischer's exact test at p <0.05. RESULTS: Infants showed different language development patterns as for

Visual dysfunction in Parkinson’s disease

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Weil, Rimona S.; Schrag, Anette E.; Warren, Jason D.; Crutch, Sebastian J.; Lees, Andrew J.; Morris, Huw R.

2016-01-01

Patients with Parkinson’s disease have a number of specific visual disturbances. These include changes in colour vision and contrast sensitivity and difficulties with complex visual tasks such as mental rotation and emotion recognition. We review changes in visual function at each stage of visual processing from retinal deficits, including contrast sensitivity and colour vision deficits to higher cortical processing impairments such as object and motion processing and neglect. We consider changes in visual function in patients with common Parkinson’s disease-associated genetic mutations including GBA and LRRK2. We discuss the association between visual deficits and clinical features of Parkinson’s disease such as rapid eye movement sleep behavioural disorder and the postural instability and gait disorder phenotype. We review the link between abnormal visual function and visual hallucinations, considering current models for mechanisms of visual hallucinations. Finally, we discuss the role of visuo-perceptual testing as a biomarker of disease and predictor of dementia in Parkinson’s disease. PMID:27412389

[Are Visual Field Defects Reversible? - Visual Rehabilitation with Brains].

Science.gov (United States)

Sabel, B A

2017-02-01

Visual field defects are considered irreversible because the retina and optic nerve do not regenerate. Nevertheless, there is some potential for recovery of the visual fields. This can be accomplished by the brain, which analyses and interprets visual information and is able to amplify residual signals through neuroplasticity. Neuroplasticity refers to the ability of the brain to change its own functional architecture by modulating synaptic efficacy. This is actually the neurobiological basis of normal learning. Plasticity is maintained throughout life and can be induced by repetitively stimulating (training) brain circuits. The question now arises as to how plasticity can be utilised to activate residual vision for the treatment of visual field loss. Just as in neurorehabilitation, visual field defects can be modulated by post-lesion plasticity to improve vision in glaucoma, diabetic retinopathy or optic neuropathy. Because almost all patients have some residual vision, the goal is to strengthen residual capacities by enhancing synaptic efficacy. New treatment paradigms have been tested in clinical studies, including vision restoration training and non-invasive alternating current stimulation. While vision training is a behavioural task to selectively stimulate "relative defects" with daily vision exercises for the duration of 6 months, treatment with alternating current stimulation (30 min. daily for 10 days) activates and synchronises the entire retina and brain. Though full restoration of vision is not possible, such treatments improve vision, both subjectively and objectively. This includes visual field enlargements, improved acuity and reaction time, improved orientation and vision related quality of life. About 70 % of the patients respond to the therapies and there are no serious adverse events. Physiological studies of the effect of alternating current stimulation using EEG and fMRI reveal massive local and global changes in the brain. These include

Adjustment to acquired vision loss in adults presenting for visual disability certification.

Science.gov (United States)

Nakade, Aditya; Rohatgi, Jolly; Bhatia, Manjeet S; Dhaliwal, Upreet

2017-03-01

Rehabilitation of the visually disabled depends on how they adjust to loss; understanding contributing factors may help in effective rehabilitation. The aim of this study is to assess adjustment to acquired vision loss in adults. This observational study, conducted in the Department of Ophthalmology at a tertiary-level teaching hospital, included thirty persons (25-65 years) with visual disability, might contribute to reducing stress and depression.

Visual Positioning Indoors: Human Eyes vs. Smartphone Cameras.

Science.gov (United States)

Wu, Dewen; Chen, Ruizhi; Chen, Liang

2017-11-16

Artificial Intelligence (AI) technologies and their related applications are now developing at a rapid pace. Indoor positioning will be one of the core technologies that enable AI applications because people spend 80% of their time indoors. Humans can locate themselves related to a visually well-defined object, e.g., a door, based on their visual observations. Can a smartphone camera do a similar job when it points to an object? In this paper, a visual positioning solution was developed based on a single image captured from a smartphone camera pointing to a well-defined object. The smartphone camera simulates the process of human eyes for the purpose of relatively locating themselves against a well-defined object. Extensive experiments were conducted with five types of smartphones on three different indoor settings, including a meeting room, a library, and a reading room. Experimental results shown that the average positioning accuracy of the solution based on five smartphone cameras is 30.6 cm, while that for the human-observed solution with 300 samples from 10 different people is 73.1 cm.

Music alters visual perception.

Directory of Open Access Journals (Sweden)

Jacob Jolij

Full Text Available BACKGROUND: Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. METHODS AND FINDINGS: We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. CONCLUSIONS: As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

Design and visualization of synthetic holograms for security applications

International Nuclear Information System (INIS)

Škeren, M; Nývlt, M; Svoboda, J

2013-01-01

In this paper we present a software for the design and visualization of holographic elements containing full scale of visual effects. It enables to simulate an observation of the holographic elements under general conditions including different light sources with various spectral and coherence properties and various geometries of reconstruction. Furthermore, recent technologies offer interesting possibilities for the 3D visualization such as the 3D techniques based on shutter or polarization glasses, anaglyphs, etc. The presented software is compatible with the mentioned techniques and enables an application of the 3D hardware tools for visualization. The software package can be used not only for visualization of the existing designs, but also for a fine tuning of the spatial, kinetic, and color properties of the hologram. Moreover, the holograms containing all types of the 3D effects, general color mixing, kinetic behavior, diffractive cryptograms, etc. can be translated using the software directly to a high resolution micro-structure.

Harnessing the web information ecosystem with wiki-based visualization dashboards.

Science.gov (United States)

McKeon, Matt

2009-01-01

We describe the design and deployment of Dashiki, a public website where users may collaboratively build visualization dashboards through a combination of a wiki-like syntax and interactive editors. Our goals are to extend existing research on social data analysis into presentation and organization of data from multiple sources, explore new metaphors for these activities, and participate more fully in the web!s information ecology by providing tighter integration with real-time data. To support these goals, our design includes novel and low-barrier mechanisms for editing and layout of dashboard pages and visualizations, connection to data sources, and coordinating interaction between visualizations. In addition to describing these technologies, we provide a preliminary report on the public launch of a prototype based on this design, including a description of the activities of our users derived from observation and interviews.

Synthetic Biology Open Language Visual (SBOL Visual) Version 2.0

KAUST Repository

Cox, Robert Sidney; Madsen, Curtis; McLaughlin, James; Nguyen, Tramy; Roehner, Nicholas; Bartley, Bryan; Bhatia, Swapnil; Bissell, Mike; Clancy, Kevin; Gorochowski, Thomas; Grunberg, Raik; Luna, Augustin; Le Novè re, Nicolas; Pocock, Matthew; Sauro, Herbert; Sexton, John T.; Stan, Guy-Bart; Tabor, Jeffrey J.; Voigt, Christopher A.; Zundel, Zach; Myers, Chris; Beal, Jacob; Wipat, Anil

2018-01-01

to produce a coherent language for expressing the structure and function of genetic designs. This document details version 2.0 of SBOL Visual, which builds on the prior SBOL Visual 1.0 standard by expanding diagram syntax to include functional interactions

Prospective, observational study comparing automated and visual point-of-care urinalysis in general practice.

Science.gov (United States)

van Delft, Sanne; Goedhart, Annelijn; Spigt, Mark; van Pinxteren, Bart; de Wit, Niek; Hopstaken, Rogier

2016-08-08

Point-of-care testing (POCT) urinalysis might reduce errors in (subjective) reading, registration and communication of test results, and might also improve diagnostic outcome and optimise patient management. Evidence is lacking. In the present study, we have studied the analytical performance of automated urinalysis and visual urinalysis compared with a reference standard in routine general practice. The study was performed in six general practitioner (GP) group practices in the Netherlands. Automated urinalysis was compared with visual urinalysis in these practices. Reference testing was performed in a primary care laboratory (Saltro, Utrecht, The Netherlands). Analytical performance of automated and visual urinalysis compared with the reference laboratory method was the primary outcome measure, analysed by calculating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) and Cohen's κ coefficient for agreement. Secondary outcome measure was the user-friendliness of the POCT analyser. Automated urinalysis by experienced and routinely trained practice assistants in general practice performs as good as visual urinalysis for nitrite, leucocytes and erythrocytes. Agreement for nitrite is high for automated and visual urinalysis. κ's are 0.824 and 0.803 (ranked as very good and good, respectively). Agreement with the central laboratory reference standard for automated and visual urinalysis for leucocytes is rather poor (0.256 for POCT and 0.197 for visual, respectively, ranked as fair and poor). κ's for erythrocytes are higher: 0.517 (automated) and 0.416 (visual), both ranked as moderate. The Urisys 1100 analyser was easy to use and considered to be not prone to flaws. Automated urinalysis performed as good as traditional visual urinalysis on reading of nitrite, leucocytes and erythrocytes in routine general practice. Implementation of automated urinalysis in general practice is justified as automation is expected to reduce

Visual short-term memory: activity supporting encoding and maintenance in retinotopic visual cortex.

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Sneve, Markus H; Alnæs, Dag; Endestad, Tor; Greenlee, Mark W; Magnussen, Svein

2012-10-15

Recent studies have demonstrated that retinotopic cortex maintains information about visual stimuli during retention intervals. However, the process by which transient stimulus-evoked sensory responses are transformed into enduring memory representations is unknown. Here, using fMRI and short-term visual memory tasks optimized for univariate and multivariate analysis approaches, we report differential involvement of human retinotopic areas during memory encoding of the low-level visual feature orientation. All visual areas show weaker responses when memory encoding processes are interrupted, possibly due to effects in orientation-sensitive primary visual cortex (V1) propagating across extrastriate areas. Furthermore, intermediate areas in both dorsal (V3a/b) and ventral (LO1/2) streams are significantly more active during memory encoding compared with non-memory (active and passive) processing of the same stimulus material. These effects in intermediate visual cortex are also observed during memory encoding of a different stimulus feature (spatial frequency), suggesting that these areas are involved in encoding processes on a higher level of representation. Using pattern-classification techniques to probe the representational content in visual cortex during delay periods, we further demonstrate that simply initiating memory encoding is not sufficient to produce long-lasting memory traces. Rather, active maintenance appears to underlie the observed memory-specific patterns of information in retinotopic cortex. Copyright © 2012 Elsevier Inc. All rights reserved.

Practice makes perfect: the neural substrates of tactile discrimination by Mah-Jong experts include the primary visual cortex

Directory of Open Access Journals (Sweden)

Honda Manabu

2006-12-01

Full Text Available Abstract Background It has yet to be determined whether visual-tactile cross-modal plasticity due to visual deprivation, particularly in the primary visual cortex (V1, is solely due to visual deprivation or if it is a result of long-term tactile training. Here we conducted an fMRI study with normally-sighted participants who had undergone long-term training on the tactile shape discrimination of the two dimensional (2D shapes on Mah-Jong tiles (Mah-Jong experts. Eight Mah-Jong experts and twelve healthy volunteers who were naïve to Mah-Jong performed a tactile shape matching task using Mah-Jong tiles with no visual input. Furthermore, seven out of eight experts performed a tactile shape matching task with unfamiliar 2D Braille characters. Results When participants performed tactile discrimination of Mah-Jong tiles, the left lateral occipital cortex (LO and V1 were activated in the well-trained subjects. In the naïve subjects, the LO was activated but V1 was not activated. Both the LO and V1 of the well-trained subjects were activated during Braille tactile discrimination tasks. Conclusion The activation of V1 in subjects trained in tactile discrimination may represent altered cross-modal responses as a result of long-term training.

Vicariously touching products through observing others' hand actions increases purchasing intention, and the effect of visual perspective in this process: An fMRI study.

Science.gov (United States)

Liu, Yi; Zang, Xuelian; Chen, Lihan; Assumpção, Leonardo; Li, Hong

2018-01-01

The growth of online shopping increases consumers' dependence on vicarious sensory experiences, such as observing others touching products in commercials. However, empirical evidence on whether observing others' sensory experiences increases purchasing intention is still scarce. In the present study, participants observed others interacting with products in the first- or third-person perspective in video clips, and their neural responses were measured with functional magnetic resonance imaging (fMRI). We investigated (1) whether and how vicariously touching certain products affected purchasing intention, and the neural correlates of this process; and (2) how visual perspective interacts with vicarious tactility. Vicarious tactile experiences were manipulated by hand actions touching or not touching the products, while the visual perspective was manipulated by showing the hand actions either in first- or third-person perspective. During the fMRI scanning, participants watched the video clips and rated their purchasing intention for each product. The results showed that, observing others touching (vs. not touching) the products increased purchasing intention, with vicarious neural responses found in mirror neuron systems (MNS) and lateral occipital complex (LOC). Moreover, the stronger neural activities in MNS was associated with higher purchasing intention. The effects of visual perspectives were found in left superior parietal lobule (SPL), while the interaction of tactility and visual perspective was shown in precuneus and precuneus-LOC connectivity. The present study provides the first evidence that vicariously touching a given product increased purchasing intention and the neural activities in bilateral MNS, LOC, left SPL and precuneus are involved in this process. Hum Brain Mapp 39:332-343, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Longterm visual associations affect attentional guidance

NARCIS (Netherlands)

Olivers, C.N.L.

2011-01-01

When observers perform a visual search task, they are assumed to adopt an attentional set for what they are looking for. The present experiment investigates the influence of long-term visual memory associations on this attentional set. On each trial, observers were asked to search a display for a

Moving Observer Support for Databases

DEFF Research Database (Denmark)

Bukauskas, Linas

Interactive visual data explorations impose rigid requirements on database and visualization systems. Systems that visualize huge amounts of data tend to request large amounts of memory resources and heavily use the CPU to process and visualize data. Current systems employ a loosely coupled...... architecture to exchange data between database and visualization. Thus, the interaction of the visualizer and the database is kept to the minimum, which most often leads to superfluous data being passed from database to visualizer. This Ph.D. thesis presents a novel tight coupling of database and visualizer....... The thesis discusses the VR-tree, an extension of the R-tree that enables observer relative data extraction. To support incremental observer position relative data extraction the thesis proposes the Volatile Access Structure (VAST). VAST is a main memory structure that caches nodes of the VR-tree. VAST...

Visual Speed of Processing and Publically Observable Feedback in Video-Game Players

OpenAIRE

Patten, James William

2016-01-01

Time spent playing action-oriented video-games has been proposed to improve the functioning of visual attention and perception in a number of areas. These benefits are not always consistently reported, however. It was hypothesized that an improvement to visual Speed of Processing (SOP) in action-oriented Video-Game Players (VGPs) underlies many of the benefits of action video-game play, and furthermore the expression of this improvement was modulated by a Hawthorne effect (individuals behavin...

Assessment of visual disability using visual evoked potentials.

Science.gov (United States)

Jeon, Jihoon; Oh, Seiyul; Kyung, Sungeun

2012-08-06

The purpose of this study is to validate the use of visual evoked potential (VEP) to objectively quantify visual acuity in normal and amblyopic patients, and determine if it is possible to predict visual acuity in disability assessment to register visual pathway lesions. A retrospective chart review was conducted of patients diagnosed with normal vision, unilateral amblyopia, optic neuritis, and visual disability who visited the university medical center for registration from March 2007 to October 2009. The study included 20 normal subjects (20 right eyes: 10 females, 10 males, ages 9-42 years), 18 unilateral amblyopic patients (18 amblyopic eyes, ages 19-36 years), 19 optic neuritis patients (19 eyes: ages 9-71 years), and 10 patients with visual disability having visual pathway lesions. Amplitude and latencies were analyzed and correlations with visual acuity (logMAR) were derived from 20 normal and 18 amblyopic subjects. Correlation of VEP amplitude and visual acuity (logMAR) of 19 optic neuritis patients confirmed relationships between visual acuity and amplitude. We calculated the objective visual acuity (logMAR) of 16 eyes from 10 patients to diagnose the presence or absence of visual disability using relations derived from 20 normal and 18 amblyopic eyes. Linear regression analyses between amplitude of pattern visual evoked potentials and visual acuity (logMAR) of 38 eyes from normal (right eyes) and amblyopic (amblyopic eyes) subjects were significant [y = -0.072x + 1.22, x: VEP amplitude, y: visual acuity (logMAR)]. There were no significant differences between visual acuity prediction values, which substituted amplitude values of 19 eyes with optic neuritis into function. We calculated the objective visual acuity of 16 eyes of 10 patients to diagnose the presence or absence of visual disability using relations of y = -0.072x + 1.22 (-0.072). This resulted in a prediction reference of visual acuity associated with malingering vs. real

Making Memories: The Development of Long-Term Visual Knowledge in Children with Visual Agnosia

Directory of Open Access Journals (Sweden)

Tiziana Metitieri

2013-01-01

Full Text Available There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2 years and 3.7 years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

Making memories: the development of long-term visual knowledge in children with visual agnosia.

Science.gov (United States)

Metitieri, Tiziana; Barba, Carmen; Pellacani, Simona; Viggiano, Maria Pia; Guerrini, Renzo

2013-01-01

There are few reports about the effects of perinatal acquired brain lesions on the development of visual perception. These studies demonstrate nonseverely impaired visual-spatial abilities and preserved visual memory. Longitudinal data analyzing the effects of compromised perceptions on long-term visual knowledge in agnosics are limited to lesions having occurred in adulthood. The study of children with focal lesions of the visual pathways provides a unique opportunity to assess the development of visual memory when perceptual input is degraded. We assessed visual recognition and visual memory in three children with lesions to the visual cortex having occurred in early infancy. We then explored the time course of visual memory impairment in two of them at 2  years and 3.7  years from the initial assessment. All children exhibited apperceptive visual agnosia and visual memory impairment. We observed a longitudinal improvement of visual memory modulated by the structural properties of objects. Our findings indicate that processing of degraded perceptions from birth results in impoverished memories. The dynamic interaction between perception and memory during development might modulate the long-term construction of visual representations, resulting in less severe impairment.

Observing how others lift light or heavy objects: which visual cues mediate the encoding of muscular force in the primary motor cortex?

Science.gov (United States)

Alaerts, Kaat; Swinnen, Stephan P; Wenderoth, Nicole

2010-06-01

Observers are able to judge quite accurately the weights lifted by others. Only recently, neuroscience has focused on the role of the motor system to accomplish this task. In this respect, a previous transcranial magnetic stimulation (TMS) study showed that the muscular force requirements of an observed action are encoded by the primary motor cortex (M1). Overall, three distinct visual sources may provide information on the applied force of an observed lifting action, namely, (i) the perceived kinematics, (ii) the hand contraction state and finally (iii) intrinsic object properties. The principal aim of the present study was to disentangle these three visual sources and to explore their importance in mediating the encoding of muscular force requirements in the observer's motor system. A series of experiments are reported in which TMS was used to measure 'force-related' responses from the hand representation in left M1 while subjects observed distinct action-stimuli. Overall, results indicated that observation-induced activity in M1 reflects the level of observed force when kinematic cues of the lift (exp. 1) or cues on the hand contraction state (exp. 2) are available. Moreover, when kinematic cues and intrinsic object properties provide distinct information on the force requirements of an observed lifting action, results from experiment 3 indicated a strong preference for the use of kinematic features in mapping the force requirements of the observed action. In general, these findings support the hypothesis that the primary motor cortex contributes to action observation by mapping the muscle-related features of observed actions. Copyright 2010 Elsevier Ltd. All rights reserved.

Perceiving Conspecifics is Not Purely Visual: “Body Gestalt” Completion is Influenced by the Body Posture of the Observer

Directory of Open Access Journals (Sweden)

K Kessler

2011-04-01

Full Text Available When we perceive other people in our everyday encounters their bodies are often partially occluded. High-level visual areas are known to automatically complete partially occluded objects, as revealed by the classic “gestalt” phenomena. However, here we set out to investigate if “body gestalt” completion is “embodied” and not purely visual. Human observers might intuitively map their own body knowledge onto partially occluded others and thereby complete their “body gestalt” by means of posture and/or motor resonance. To this end we developed new stimuli showing a face and two hands that could either form a “body gestalt” or not. Our most important finding across five behavioural experiments was that body gestalt completion was not solely based on visual features like the classic gestalt phenomena. Responses were significantly faster when the observer's posture matched the configuration of face and hands shown on screen then. In this sense body gestalt completion is an embodied process, where humans intuitively use their own body knowledge to ‘fill in the gaps’ in a body stimulus. We further conclude that in our particular paradigm posture resonance was apparently more important for body gestalt completion than motor resonance—with the former being most likely mediated by proprioceptive body schema representations, while the latter by the mirror neuron system. Finally, we will also present preliminary analysis of MEG data. Our findings elucidate the mechanisms of how humans perceive others holistically and how they might implicitly align themselves in everyday social interactions to facilitate an optimal co-representation of each other.

EDITORIAL: Focus on Visualization in Physics FOCUS ON VISUALIZATION IN PHYSICS

Science.gov (United States)

Sanders, Barry C.; Senden, Tim; Springel, Volker

2008-12-01

cosmology wherein this (in principle invisible) dark matter dominates the cosmic matter content. The advantages of visualization found for simulated data also hold for real world data as well. With the application of computerized acquisition many scientific disciplines are witnessing exponential growth rates of the volume of accumulated raw data, which often makes it daunting to condense the information into a manageable form, a challenge that can be addressed by modern visualization techniques. Such visualizations are also often an enticing way to communicate scientific results to the general public. This need for visualization is especially true in basic science, with its reliance on a benevolent and interested general public that drives the need for high-quality visualizations. Despite the widespread use of visualization, this technology has suffered from a lack of the unifying influence of shared common experiences. As with any emerging technology practitioners have often independently found solutions to similar problems. It is the aim of this focus issue to celebrate the importance of visualization, report on its growing use by the broad community of physicists, including biophysics, chemical physics, geophysics, astrophysics, and medical physics, and provide an opportunity for the diverse community of scientists using visualization to share work in one issue of a journal that itself is in the vanguard of supporting visualization and multimedia. A remarkable breadth and diversity of visualization in physics is to be found in this issue spanning fundamental aspects of relativity theory to computational fluid dynamics. The topics span length scales that are as small as quantum phenomena to the entire observable Universe. We have been impressed by the quality of the submissions and hope that this snap-shot will introduce, inform, motivate and maybe even help to unify visualization in physics. Readers are also directed to the December issue of Physics World which includes

Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

Science.gov (United States)

Meyer, Georg F; Shao, Fei; White, Mark D; Hopkins, Carl; Robotham, Antony J

2013-01-01

Externally generated visual motion signals can cause the illusion of self-motion in space (vection) and corresponding visually evoked postural responses (VEPR). These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR) environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1) visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2) real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3) visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

Designing Data Visualizations Representing Informational Relationships

CERN Document Server

Steele, Julie

2011-01-01

Data visualization is an efficient and effective medium for communicating large amounts of information, but the design process can often seem like an unexplainable creative endeavor. This concise book aims to demystify the design process by showing you how to use a linear decision-making process to encode your information visually. Delve into different kinds of visualization, including infographics and visual art, and explore the influences at work in each one. Then learn how to apply these concepts to your design process. Learn data visualization classifications, including explanatory, expl

Incremental Observer Relative Data Extraction

DEFF Research Database (Denmark)

Bukauskas, Linas; Bøhlen, Michael Hanspeter

2004-01-01

The visual exploration of large databases calls for a tight coupling of database and visualization systems. Current visualization systems typically fetch all the data and organize it in a scene tree that is then used to render the visible data. For immersive data explorations in a Cave...... or a Panorama, where an observer is data space this approach is far from optimal. A more scalable approach is to make the observer-aware database system and to restrict the communication between the database and visualization systems to the relevant data. In this paper VR-tree, an extension of the R......-tree, is used to index visibility ranges of objects. We introduce a new operator for incremental Observer Relative data Extraction (iORDE). We propose the Volatile Access STructure (VAST), a lightweight main memory structure that is created on the fly and is maintained during visual data explorations. VAST...

Developing Verbal and Visual Literacy through Experiences in the Visual Arts: 25 Tips for Teachers

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Johnson, Margaret H.

2008-01-01

Including talk about art--conversing with children about artwork, their own and others'--as a component of visual art activities extends children's experiences in and understanding of visual messages. Johnson discusses practices that help children develop visual and verbal expression through active experiences with the visual arts. She offers 25…

Negative emotion boosts quality of visual working memory representation.

Science.gov (United States)

Xie, Weizhen; Zhang, Weiwei

2016-08-01

Negative emotion impacts a variety of cognitive processes, including working memory (WM). The present study investigated whether negative emotion modulated WM capacity (quantity) or resolution (quality), 2 independent limits on WM storage. In Experiment 1, observers tried to remember several colors over 1-s delay and then recalled the color of a randomly picked memory item by clicking a best-matching color on a continuous color wheel. On each trial, before the visual WM task, 1 of 3 emotion conditions (negative, neutral, or positive) was induced by having observers to rate the valence of an International Affective Picture System image. Visual WM under negative emotion showed enhanced resolution compared with neutral and positive conditions, whereas the number of retained representations was comparable across the 3 emotion conditions. These effects were generalized to closed-contour shapes in Experiment 2. To isolate the locus of these effects, Experiment 3 adopted an iconic memory version of the color recall task by eliminating the 1-s retention interval. No significant change in the quantity or quality of iconic memory was observed, suggesting that the resolution effects in the first 2 experiments were critically dependent on the need to retain memory representations over a short period of time. Taken together, these results suggest that negative emotion selectively boosts visual WM quality, supporting the dissociable nature quantitative and qualitative aspects of visual WM representation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A link between visual disambiguation and visual memory.

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Hegdé, Jay; Kersten, Daniel

2010-11-10

Sensory information in the retinal image is typically too ambiguous to support visual object recognition by itself. Theories of visual disambiguation posit that to disambiguate, and thus interpret, the incoming images, the visual system must integrate the sensory information with previous knowledge of the visual world. However, the underlying neural mechanisms remain unclear. Using functional magnetic resonance imaging (fMRI) of human subjects, we have found evidence for functional specialization for storing disambiguating information in memory versus interpreting incoming ambiguous images. Subjects viewed two-tone, "Mooney" images, which are typically ambiguous when seen for the first time but are quickly disambiguated after viewing the corresponding unambiguous color images. Activity in one set of regions, including a region in the medial parietal cortex previously reported to play a key role in Mooney image disambiguation, closely reflected memory for previously seen color images but not the subsequent disambiguation of Mooney images. A second set of regions, including the superior temporal sulcus, showed the opposite pattern, in that their responses closely reflected the subjects' percepts of the disambiguated Mooney images on a stimulus-to-stimulus basis but not the memory of the corresponding color images. Functional connectivity between the two sets of regions was stronger during those trials in which the disambiguated percept was stronger. This functional interaction between brain regions that specialize in storing disambiguating information in memory versus interpreting incoming ambiguous images may represent a general mechanism by which previous knowledge disambiguates visual sensory information.

A Geometric Approach to Visualization of Variability in Functional Data

KAUST Repository

Xie, Weiyi

2016-12-19

We propose a new method for the construction and visualization of boxplot-type displays for functional data. We use a recent functional data analysis framework, based on a representation of functions called square-root slope functions, to decompose observed variation in functional data into three main components: amplitude, phase, and vertical translation. We then construct separate displays for each component, using the geometry and metric of each representation space, based on a novel definition of the median, the two quartiles, and extreme observations. The outlyingness of functional data is a very complex concept. Thus, we propose to identify outliers based on any of the three main components after decomposition. We provide a variety of visualization tools for the proposed boxplot-type displays including surface plots. We evaluate the proposed method using extensive simulations and then focus our attention on three real data applications including exploratory data analysis of sea surface temperature functions, electrocardiogram functions and growth curves.

Effect of neodymium:YAG laser capsulotomy on visual function in patients with posterior capsule opacification and good visual acuity.

Science.gov (United States)

Yotsukura, Erisa; Torii, Hidemasa; Saiki, Megumi; Negishi, Kazuno; Tsubota, Kazuo

2016-03-01

To evaluate the effect of neodymium:YAG (Nd:YAG) laser capsulotomy on the visual function in patients with posterior capsule opacification (PCO) and good visual acuity. Keio University Hospital, Tokyo, Japan. Observational case series. Eyes were evaluated that had previous cataract surgery with a clinical diagnosis of PCO requiring Nd:YAG laser capsulotomy regardless of a good corrected distance visual acuity (CDVA) (at least 20/20). The CDVA, 10% low contrast visual acuity (LCVA), wavefront aberrations from the 3rd to 6th order, and retinal straylight were measured before and after Nd:YAG laser capsulotomy. The study included 16 eyes of 16 patients (10 men, 6 women; mean age 69.5 years ± 9.3 [SD]). The mean CDVA, LCVA, and straylight after Nd:YAG laser capsulotomy improved significantly (P The root mean square (RMS) of the 3rd Zernike coefficients (S3) and the RMS of the total higher-order aberrations (HOAs) from the 3rd to 6th order decreased significantly after capsulotomy (P The straylight correlated significantly with the total HOAs (r = 0.727, P = .002) and S3 (r = 0.748, P = .001) before capsulotomy. Subjective symptoms resolved after capsulotomy in all cases. Neodymium:YAG laser capsulotomy enabled a significant improvement in visual function even in patients with PCO with good visual acuity. Straylight measurements might be useful to determine the indications for Nd:YAG laser capsulotomy when patients report visual disturbances without decreased visual acuity. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Exclusively visual analysis of classroom group interactions

Science.gov (United States)

Tucker, Laura; Scherr, Rachel E.; Zickler, Todd; Mazur, Eric

2016-12-01

Large-scale audiovisual data that measure group learning are time consuming to collect and analyze. As an initial step towards scaling qualitative classroom observation, we qualitatively coded classroom video using an established coding scheme with and without its audio cues. We find that interrater reliability is as high when using visual data only—without audio—as when using both visual and audio data to code. Also, interrater reliability is high when comparing use of visual and audio data to visual-only data. We see a small bias to code interactions as group discussion when visual and audio data are used compared with video-only data. This work establishes that meaningful educational observation can be made through visual information alone. Further, it suggests that after initial work to create a coding scheme and validate it in each environment, computer-automated visual coding could drastically increase the breadth of qualitative studies and allow for meaningful educational analysis on a far greater scale.

Exclusively visual analysis of classroom group interactions

Directory of Open Access Journals (Sweden)

Laura Tucker

2016-11-01

Full Text Available Large-scale audiovisual data that measure group learning are time consuming to collect and analyze. As an initial step towards scaling qualitative classroom observation, we qualitatively coded classroom video using an established coding scheme with and without its audio cues. We find that interrater reliability is as high when using visual data only—without audio—as when using both visual and audio data to code. Also, interrater reliability is high when comparing use of visual and audio data to visual-only data. We see a small bias to code interactions as group discussion when visual and audio data are used compared with video-only data. This work establishes that meaningful educational observation can be made through visual information alone. Further, it suggests that after initial work to create a coding scheme and validate it in each environment, computer-automated visual coding could drastically increase the breadth of qualitative studies and allow for meaningful educational analysis on a far greater scale.

Postdictive modulation of visual orientation.

Science.gov (United States)

Kawabe, Takahiro

2012-01-01

The present study investigated how visual orientation is modulated by subsequent orientation inputs. Observers were presented a near-vertical Gabor patch as a target, followed by a left- or right-tilted second Gabor patch as a distracter in the spatial vicinity of the target. The task of the observers was to judge whether the target was right- or left-tilted (Experiment 1) or whether the target was vertical or not (Supplementary experiment). The judgment was biased toward the orientation of the distracter (the postdictive modulation of visual orientation). The judgment bias peaked when the target and distracter were temporally separated by 100 ms, indicating a specific temporal mechanism for this phenomenon. However, when the visibility of the distracter was reduced via backward masking, the judgment bias disappeared. On the other hand, the low-visibility distracter could still cause a simultaneous orientation contrast, indicating that the distracter orientation is still processed in the visual system (Experiment 2). Our results suggest that the postdictive modulation of visual orientation stems from spatiotemporal integration of visual orientation on the basis of a slow feature matching process.

Designing Visual Character Of Raden Wijaya As Historical Figure In Visual Novel

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Dendi Pratama

2017-11-01

Full Text Available Visual character in Visual Novel games have the power to carry messages. Creation of visual characters in historical narratives can also bring cultural meaning. This study examines the creation of Raden Wijaya visual character as a case example in Visual Novel Twist Majapahit which is set in Majapahit kingdom but with manga-style visualization. On the contrary the creation of Raden Wijaya visual character in this study is more trying to accentuate the characteristic of Indonesia. The choice of Raden Wijaya character is based on consideration because it has historically included a major influence in expanding the royal power. The study discussions are elaborated qualitatively with the Social Semiotic approach that analyzes informative functions interactive functions and imaginative functions in visual character design elements. The results of this study show that design elements can build a comprehensive association of meanings so that the creation of visual characters tailored to historical figures has the potential to bring cultural messages.

Widespread correlation patterns of fMRI signal across visual cortex reflect eccentricity organization

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Arcaro, Michael J; Honey, Christopher J; Mruczek, Ryan EB; Kastner, Sabine; Hasson, Uri

2015-01-01

The human visual system can be divided into over two-dozen distinct areas, each of which contains a topographic map of the visual field. A fundamental question in vision neuroscience is how the visual system integrates information from the environment across different areas. Using neuroimaging, we investigated the spatial pattern of correlated BOLD signal across eight visual areas on data collected during rest conditions and during naturalistic movie viewing. The correlation pattern between areas reflected the underlying receptive field organization with higher correlations between cortical sites containing overlapping representations of visual space. In addition, the correlation pattern reflected the underlying widespread eccentricity organization of visual cortex, in which the highest correlations were observed for cortical sites with iso-eccentricity representations including regions with non-overlapping representations of visual space. This eccentricity-based correlation pattern appears to be part of an intrinsic functional architecture that supports the integration of information across functionally specialized visual areas. DOI: http://dx.doi.org/10.7554/eLife.03952.001 PMID:25695154

38 CFR 4.76 - Visual acuity.

Science.gov (United States)

2010-07-01

... DISABILITIES Disability Ratings The Organs of Special Sense § 4.76 Visual acuity. (a) Examination of visual acuity. Examination of visual acuity must include the central uncorrected and corrected visual acuity for... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Visual acuity. 4.76...

Write like a visual artist: Tracing the textually mediated art world

Directory of Open Access Journals (Sweden)

Janna Klostermann

2016-12-01

Full Text Available This study examines the social organisation of Canada’s art world from the standpoint of practising visual artists. Bringing together theories of literacy and institutional ethnography, the article investigates the literacy practices of visual artists, making visible how artists use written texts to participate in public galleries and in the social and institutional relations of the art world. Drawing on extended ethnographic research, including interviews, observational field notes and textual analyses, this study sheds light on the ways visual artists enact particular texts, enact organisational processes, and to enact the social and conceptual worlds they are a part of. Through the lens of visual artists, this study locates two particular texts – the artist statement and the bio statement – in the extended social and institutional relations of the art world.

Opposite brain laterality in analogous auditory and visual tests.

Science.gov (United States)

Oltedal, Leif; Hugdahl, Kenneth

2017-11-01

Laterality for language processing can be assessed by auditory and visual tasks. Typically, a right ear/right visual half-field (VHF) advantage is observed, reflecting left-hemispheric lateralization for language. Historically, auditory tasks have shown more consistent and reliable results when compared to VHF tasks. While few studies have compared analogous tasks applied to both sensory modalities for the same participants, one such study by Voyer and Boudreau [(2003). Cross-modal correlation of auditory and visual language laterality tasks: a serendipitous finding. Brain Cogn, 53(2), 393-397] found opposite laterality for visual and auditory language tasks. We adapted an experimental paradigm based on a dichotic listening and VHF approach, and applied the combined language paradigm in two separate experiments, including fMRI in the second experiment to measure brain activation in addition to behavioural data. The first experiment showed a right-ear advantage for the auditory task, but a left half-field advantage for the visual task. The second experiment, confirmed the findings, with opposite laterality effects for the visual and auditory tasks. In conclusion, we replicate the finding by Voyer and Boudreau (2003) and support their interpretation that these visual and auditory language tasks measure different cognitive processes.

Visual dysfunction, neurodegenerative diseases, and aging.

Science.gov (United States)

Jackson, Gregory R; Owsley, Cynthia

2003-08-01

The four most common sight-threatening conditions in older adults in North America are cataract, ARM, glaucoma, and diabetic retinopathy. Even in their moderate stages, these conditions cause visual sensory impairments and reductions in health-related quality of life, including difficulties in daily tasks and psychosocial problems. Many older adults are free from these conditions, yet still experience a variety of visual perceptual problems resulting from aging-related changes in the optics of the eye and degeneration of the visual neural pathways. These problems consist of impairments in visual acuity, contrast sensitivity, color discrimination, temporal sensitivity, motion perception, peripheral visual field sensitivity, and visual processing speed. PD causes a progressive loss of dopaminergic cells predominantly in the retina and possibly in other areas of the visual system. This retinal dopamine deficiency produces selective spatial-temporal abnormalities in retinal ganglion cell function, probably arising from altered receptive field organization in the PD retina. The cortical degeneration characteristics of AD, including neurofibrillary tangles and neuritic plaques, also are present in the visual cortical areas, especially in the visual association areas. The most prominent electrophysiologic change in AD is a delay in the P2 component of the flash VEP. Deficits in higher-order visual abilities typically are compromised in AD, including problems with visual attention, perceiving structure from motion, visual memory, visual learning, reading, and object and face perception. There have been reports of a visual variant of AD in which these types of visual problems are the initial and most prominent signs of the disease. Visual sensory impairments (e.g., contrast sensitivity or achromatopsia) also have been reported but are believed more reflective of cortical disturbances than of AD-associated optic neuropathy.

Modulation of visually evoked postural responses by contextual visual, haptic and auditory information: a 'virtual reality check'.

Directory of Open Access Journals (Sweden)

Georg F Meyer

Full Text Available Externally generated visual motion signals can cause the illusion of self-motion in space (vection and corresponding visually evoked postural responses (VEPR. These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1 visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2 real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3 visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR.

Visual Literacy: Does It Enhance Leadership Abilities Required for the Twenty-First Century?

Science.gov (United States)

Bintz, Carol

2016-01-01

The twenty-first century hosts a well-established global economy, where leaders are required to have increasingly complex skills that include creativity, innovation, vision, relatability, critical thinking and well-honed communications methods. The experience gained by learning to be visually literate includes the ability to see, observe, analyze,…

Modulation of Visually Evoked Postural Responses by Contextual Visual, Haptic and Auditory Information: A ‘Virtual Reality Check’

Science.gov (United States)

Meyer, Georg F.; Shao, Fei; White, Mark D.; Hopkins, Carl; Robotham, Antony J.

2013-01-01

Externally generated visual motion signals can cause the illusion of self-motion in space (vection) and corresponding visually evoked postural responses (VEPR). These VEPRs are not simple responses to optokinetic stimulation, but are modulated by the configuration of the environment. The aim of this paper is to explore what factors modulate VEPRs in a high quality virtual reality (VR) environment where real and virtual foreground objects served as static visual, auditory and haptic reference points. Data from four experiments on visually evoked postural responses show that: 1) visually evoked postural sway in the lateral direction is modulated by the presence of static anchor points that can be haptic, visual and auditory reference signals; 2) real objects and their matching virtual reality representations as visual anchors have different effects on postural sway; 3) visual motion in the anterior-posterior plane induces robust postural responses that are not modulated by the presence of reference signals or the reality of objects that can serve as visual anchors in the scene. We conclude that automatic postural responses for laterally moving visual stimuli are strongly influenced by the configuration and interpretation of the environment and draw on multisensory representations. Different postural responses were observed for real and virtual visual reference objects. On the basis that automatic visually evoked postural responses in high fidelity virtual environments should mimic those seen in real situations we propose to use the observed effect as a robust objective test for presence and fidelity in VR. PMID:23840760

The Avian Knowledge Network : A partnership to organize, analyze, and visualize bird observation data for education, conservation, research, and land management

Science.gov (United States)

Marshall Iliff; Leo Salas; Ernesto Ruelas Inzunza; Grant Ballard; Denis Lepage; Steve Kelling

2009-01-01

The Avian Knowledge Network (AKN) is an international collaboration of academic, nongovernment, and government institutions with the goal of organizing observations of birds into an interoperable format to enhance access, data visualization and exploration, and scientifi c analyses. The AKN uses proven cyberinfrastructure and informatics techniques as the foundation of...

Temporal visual field defects are associated with monocular inattention in chiasmal pathology.

Science.gov (United States)

Fledelius, Hans C

2009-11-01

Chiasmal lesions have been shown to give rise occasionally to uni-ocular temporal inattention, which cannot be compensated for by volitional eye movement. This article describes the assessments of 46 such patients with chiasmal pathology. It aims to determine the clinical spectrum of this disorder, including interference with reading. Retrospective consecutive observational clinical case study over a 7-year period comprising 46 patients with chiasmal field loss of varying degrees. Observation of reading behaviour during monocular visual acuity testing ascertained from consecutive patients who appeared unable to read optotypes on the temporal side of the chart. Visual fields were evaluated by kinetic (Goldmann) and static (Octopus) techniques. Five patients who clearly manifested this condition are presented in more detail. The results of visual field testing were related to absence or presence of uni-ocular visual inattentive behaviour for distance visual acuity testing and/or reading printed text. Despite normal eye movements, the 46 patients making up the clinical series perceived only optotypes in the nasal part of the chart, in one eye or in both, when tested for each eye in turn. The temporal optotypes were ignored, and this behaviour persisted despite instruction to search for any additional letters temporal to those, which had been seen. This phenomenon of unilateral visual inattention held for both eyes in 18 and was unilateral in the remaining 28 patients. Partial or full reversibility after treatment was recorded in 21 of the 39 for whom reliable follow-up data were available. Reading a text was affected in 24 individuals, and permanently so in six. A neglect-like spatial unawareness and a lack of cognitive compensation for varying degrees of temporal visual field loss were present in all the patients observed. Not only is visual field loss a feature of chiasmal pathology, but the higher visual function of affording attention within the temporal visual

The role of visual representation in physics learning: dynamic versus static visualization

Science.gov (United States)

Suyatna, Agus; Anggraini, Dian; Agustina, Dina; Widyastuti, Dini

2017-11-01

This study aims to examine the role of visual representation in physics learning and to compare the learning outcomes of using dynamic and static visualization media. The study was conducted using quasi-experiment with Pretest-Posttest Control Group Design. The samples of this research are students of six classes at State Senior High School in Lampung Province. The experimental class received a learning using dynamic visualization and control class using static visualization media. Both classes are given pre-test and post-test with the same instruments. Data were tested with N-gain analysis, normality test, homogeneity test and mean difference test. The results showed that there was a significant increase of mean (N-Gain) learning outcomes (p physical phenomena and requires long-term observation.

Changes in visual and sensory-motor resting-state functional connectivity support motor learning by observing

Science.gov (United States)

McGregor, Heather R.

2015-01-01

Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153–160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493–1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289–2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989–994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, Fogassi L, Gallese V, Seitz RJ, Zilles K, Rizzolatti G, Freund HJ. Eur J Neurosci 13: 400–404, 2001; Iacoboni M, Woods RP, Brass M, Bekkering H, Mazziotta JC, Rizzolatti G. Science 286: 2526–2528, 1999), and eye tracking (Flanagan JR, Johansson RS. Nature 424: 769–771, 2003) studies. Here we used a force field learning paradigm coupled with resting-state fMRI to investigate the brain areas involved in motor learning by observing. We examined changes in resting-state functional connectivity (FC) after an observational learning task and found a network consisting of V5/MT, cerebellum, and primary motor and somatosensory cortices in which changes in FC were correlated with the amount of motor learning achieved through observation, as assessed behaviorally after resting-state fMRI scans. The observed FC changes in this network are not due to visual attention to motion or observation of movement errors but rather are specifically linked to motor learning. These results support the idea that brain networks linking action observation and motor control also facilitate motor learning. PMID:25995349

Changes in visual and sensory-motor resting-state functional connectivity support motor learning by observing.

Science.gov (United States)

McGregor, Heather R; Gribble, Paul L

2015-07-01

Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153-160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493-1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289-2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989-994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, Fogassi L, Gallese V, Seitz RJ, Zilles K, Rizzolatti G, Freund HJ. Eur J Neurosci 13: 400-404, 2001; Iacoboni M, Woods RP, Brass M, Bekkering H, Mazziotta JC, Rizzolatti G. Science 286: 2526-2528, 1999), and eye tracking (Flanagan JR, Johansson RS. Nature 424: 769-771, 2003) studies. Here we used a force field learning paradigm coupled with resting-state fMRI to investigate the brain areas involved in motor learning by observing. We examined changes in resting-state functional connectivity (FC) after an observational learning task and found a network consisting of V5/MT, cerebellum, and primary motor and somatosensory cortices in which changes in FC were correlated with the amount of motor learning achieved through observation, as assessed behaviorally after resting-state fMRI scans. The observed FC changes in this network are not due to visual attention to motion or observation of movement errors but rather are specifically linked to motor learning. These results support the idea that brain networks linking action observation and motor control also facilitate motor learning. Copyright © 2015 the American Physiological Society.

Perceptual learning in children with visual impairment improves near visual acuity.

Science.gov (United States)

Huurneman, Bianca; Boonstra, F Nienke; Cox, Ralf F A; van Rens, Ger; Cillessen, Antonius H N

2013-09-17

This study investigated whether visual perceptual learning can improve near visual acuity and reduce foveal crowding effects in four- to nine-year-old children with visual impairment. Participants were 45 children with visual impairment and 29 children with normal vision. Children with visual impairment were divided into three groups: a magnifier group (n = 12), a crowded perceptual learning group (n = 18), and an uncrowded perceptual learning group (n = 15). Children with normal vision also were divided in three groups, but were measured only at baseline. Dependent variables were single near visual acuity (NVA), crowded NVA, LH line 50% crowding NVA, number of trials, accuracy, performance time, amount of small errors, and amount of large errors. Children with visual impairment trained during six weeks, two times per week, for 30 minutes (12 training sessions). After training, children showed significant improvement of NVA in addition to specific improvements on the training task. The crowded perceptual learning group showed the largest acuity improvements (1.7 logMAR lines on the crowded chart, P children in the crowded perceptual learning group showed improvements on all NVA charts. Children with visual impairment benefit from perceptual training. While task-specific improvements were observed in all training groups, transfer to crowded NVA was largest in the crowded perceptual learning group. To our knowledge, this is the first study to provide evidence for the improvement of NVA by perceptual learning in children with visual impairment. (http://www.trialregister.nl number, NTR2537.).

Different Strokes for Different Folks: Visual Presentation Design between Disciplines.

Science.gov (United States)

Gomez, S R; Jianu, R; Ziemkiewicz, C; Guo, Hua; Laidlaw, D H

2012-12-01

We present an ethnographic study of design differences in visual presentations between academic disciplines. Characterizing design conventions between users and data domains is an important step in developing hypotheses, tools, and design guidelines for information visualization. In this paper, disciplines are compared at a coarse scale between four groups of fields: social, natural, and formal sciences; and the humanities. Two commonplace presentation types were analyzed: electronic slideshows and whiteboard "chalk talks". We found design differences in slideshows using two methods - coding and comparing manually-selected features, like charts and diagrams, and an image-based analysis using PCA called eigenslides. In whiteboard talks with controlled topics, we observed design behaviors, including using representations and formalisms from a participant's own discipline, that suggest authors might benefit from novel assistive tools for designing presentations. Based on these findings, we discuss opportunities for visualization ethnography and human-centered authoring tools for visual information.

Visual cognition

Energy Technology Data Exchange (ETDEWEB)

Pinker, S.

1985-01-01

This book consists of essays covering issues in visual cognition presenting experimental techniques from cognitive psychology, methods of modeling cognitive processes on computers from artificial intelligence, and methods of studying brain organization from neuropsychology. Topics considered include: parts of recognition; visual routines; upward direction; mental rotation, and discrimination of left and right turns in maps; individual differences in mental imagery, computational analysis and the neurological basis of mental imagery: componental analysis.

Reliability of visual and instrumental color matching.

Science.gov (United States)

Igiel, Christopher; Lehmann, Karl Martin; Ghinea, Razvan; Weyhrauch, Michael; Hangx, Ysbrand; Scheller, Herbert; Paravina, Rade D

2017-09-01

The aim of this investigation was to evaluate intra-rater and inter-rater reliability of visual and instrumental shade matching. Forty individuals with normal color perception participated in this study. The right maxillary central incisor of a teaching model was prepared and restored with 10 feldspathic all-ceramic crowns of different shades. A shade matching session consisted of the observer (rater) visually selecting the best match by using VITA classical A1-D4 (VC) and VITA Toothguide 3D Master (3D) shade guides and the VITA Easyshade Advance intraoral spectrophotometer (ES) to obtain both VC and 3D matches. Three shade matching sessions were held with 4 to 6 weeks between sessions. Intra-rater reliability was assessed based on the percentage of agreement for the three sessions for the same observer, whereas the inter-rater reliability was calculated as mean percentage of agreement between different observers. The Fleiss' Kappa statistical analysis was used to evaluate visual inter-rater reliability. The mean intra-rater reliability for the visual shade selection was 64(11) for VC and 48(10) for 3D. The corresponding ES values were 96(4) for both VC and 3D. The percentages of observers who matched the same shade with VC and 3D were 55(10) and 43(12), respectively, while corresponding ES values were 88(8) for VC and 92(4) for 3D. The results for visual shade matching exhibited a high to moderate level of inconsistency for both intra-rater and inter-rater comparisons. The VITA Easyshade Advance intraoral spectrophotometer exhibited significantly better reliability compared with visual shade selection. This study evaluates the ability of observers to consistently match the same shade visually and with a dental spectrophotometer in different sessions. The intra-rater and inter-rater reliability (agreement of repeated shade matching) of visual and instrumental tooth color matching strongly suggest the use of color matching instruments as a supplementary tool in

Statistical Analysis of a Comprehensive List of Visual Binaries

Directory of Open Access Journals (Sweden)

Kovaleva D.

2015-12-01

Full Text Available Visual binary stars are the most abundant class of observed binaries. The most comprehensive list of data on visual binaries compiled recently by cross-matching the largest catalogues of visual binaries allowed a statistical investigation of observational parameters of these systems. The dataset was cleaned by correcting uncertainties and misclassifications, and supplemented with available parallax data. The refined dataset is free from technical biases and contains 3676 presumably physical visual pairs of luminosity class V with known angular separations, magnitudes of the components, spectral types, and parallaxes. We also compiled a restricted sample of 998 pairs free from observational biases due to the probability of binary discovery. Certain distributions of observational and physical parameters of stars of our dataset are discussed.

Auditory, visual and auditory-visual memory and sequencing performance in typically developing children.

Science.gov (United States)

Pillai, Roshni; Yathiraj, Asha

2017-09-01

The study evaluated whether there exists a difference/relation in the way four different memory skills (memory score, sequencing score, memory span, & sequencing span) are processed through the auditory modality, visual modality and combined modalities. Four memory skills were evaluated on 30 typically developing children aged 7 years and 8 years across three modality conditions (auditory, visual, & auditory-visual). Analogous auditory and visual stimuli were presented to evaluate the three modality conditions across the two age groups. The children obtained significantly higher memory scores through the auditory modality compared to the visual modality. Likewise, their memory scores were significantly higher through the auditory-visual modality condition than through the visual modality. However, no effect of modality was observed on the sequencing scores as well as for the memory and the sequencing span. A good agreement was seen between the different modality conditions that were studied (auditory, visual, & auditory-visual) for the different memory skills measures (memory scores, sequencing scores, memory span, & sequencing span). A relatively lower agreement was noted only between the auditory and visual modalities as well as between the visual and auditory-visual modality conditions for the memory scores, measured using Bland-Altman plots. The study highlights the efficacy of using analogous stimuli to assess the auditory, visual as well as combined modalities. The study supports the view that the performance of children on different memory skills was better through the auditory modality compared to the visual modality. Copyright © 2017 Elsevier B.V. All rights reserved.

Topological Methods for Visualization

Energy Technology Data Exchange (ETDEWEB)

Berres, Anne Sabine [Los Alamos National Lab. (LANL), Los Alamos, NM (United Stat

2016-04-07

This slide presentation describes basic topological concepts, including topological spaces, homeomorphisms, homotopy, betti numbers. Scalar field topology explores finding topological features and scalar field visualization, and vector field topology explores finding topological features and vector field visualization.

Multidimensional structured data visualization method and apparatus, text visualization method and apparatus, method and apparatus for visualizing and graphically navigating the world wide web, method and apparatus for visualizing hierarchies

Science.gov (United States)

Risch, John S [Kennewick, WA; Dowson, Scott T [West Richland, WA; Hart, Michelle L [Richland, WA; Hatley, Wes L [Kennewick, WA

2008-05-13

A method of displaying correlations among information objects comprises receiving a query against a database; obtaining a query result set; and generating a visualization representing the components of the result set, the visualization including one of a plane and line to represent a data field, nodes representing data values, and links showing correlations among fields and values. Other visualization methods and apparatus are disclosed.

Visual, Algebraic and Mixed Strategies in Visually Presented Linear Programming Problems.

Science.gov (United States)

Shama, Gilli; Dreyfus, Tommy

1994-01-01

Identified and classified solution strategies of (n=49) 10th-grade students who were presented with linear programming problems in a predominantly visual setting in the form of a computerized game. Visual strategies were developed more frequently than either algebraic or mixed strategies. Appendix includes questionnaires. (Contains 11 references.)…

Postdictive modulation of visual orientation.

Directory of Open Access Journals (Sweden)

Takahiro Kawabe

Full Text Available The present study investigated how visual orientation is modulated by subsequent orientation inputs. Observers were presented a near-vertical Gabor patch as a target, followed by a left- or right-tilted second Gabor patch as a distracter in the spatial vicinity of the target. The task of the observers was to judge whether the target was right- or left-tilted (Experiment 1 or whether the target was vertical or not (Supplementary experiment. The judgment was biased toward the orientation of the distracter (the postdictive modulation of visual orientation. The judgment bias peaked when the target and distracter were temporally separated by 100 ms, indicating a specific temporal mechanism for this phenomenon. However, when the visibility of the distracter was reduced via backward masking, the judgment bias disappeared. On the other hand, the low-visibility distracter could still cause a simultaneous orientation contrast, indicating that the distracter orientation is still processed in the visual system (Experiment 2. Our results suggest that the postdictive modulation of visual orientation stems from spatiotemporal integration of visual orientation on the basis of a slow feature matching process.

Accessing Earth Science Data Visualizations through NASA GIBS & Worldview

Science.gov (United States)

Cechini, M. F.; Boller, R. A.; Baynes, K.; Wong, M. M.; King, B. A.; Schmaltz, J. E.; De Luca, A. P.; King, J.; Roberts, J. T.; Rodriguez, J.; Thompson, C. K.; Pressley, N. N.

2017-12-01

For more than 20 years, the NASA Earth Observing System (EOS) has operated dozens of remote sensing satellites collecting nearly 15 Petabytes of data that span thousands of science parameters. Within these observations are keys the Earth Scientists have used to unlock many things that we understand about our planet. Also contained within these observations are a myriad of opportunities for learning and education. The trick is making them accessible to educators and students in convenient and simple ways so that effort can be spent on lesson enrichment and not overcoming technical hurdles. The NASA Global Imagery Browse Services (GIBS) system and NASA Worldview website provide a unique view into EOS data through daily full resolution visualizations of hundreds of earth science parameters. For many of these parameters, visualizations are available within hours of acquisition from the satellite. For others, visualizations are available for the entire mission of the satellite. Accompanying the visualizations are visual aids such as color legends, place names, and orbit tracks. By using these visualizations, educators and students can observe natural phenomena that enrich a scientific education. This poster will provide an overview of the visualizations available in NASA GIBS and Worldview and how they are accessed. We invite discussion on how the visualizations can be used or improved for educational purposes.

'You see?' Teaching and learning how to interpret visual cues during surgery.

Science.gov (United States)

Cope, Alexandra C; Bezemer, Jeff; Kneebone, Roger; Lingard, Lorelei

2015-11-01

The ability to interpret visual cues is important in many medical specialties, including surgery, in which poor outcomes are largely attributable to errors of perception rather than poor motor skills. However, we know little about how trainee surgeons learn to make judgements in the visual domain. We explored how trainees learn visual cue interpretation in the operating room. A multiple case study design was used. Participants were postgraduate surgical trainees and their trainers. Data included observer field notes, and integrated video- and audio-recordings from 12 cases representing more than 11 hours of observation. A constant comparative methodology was used to identify dominant themes. Visual cue interpretation was a recurrent feature of trainer-trainee interactions and was achieved largely through the pedagogic mechanism of co-construction. Co-construction was a dialogic sequence between trainer and trainee in which they explored what they were looking at together to identify and name structures or pathology. Co-construction took two forms: 'guided co-construction', in which the trainer steered the trainee to see what the trainer was seeing, and 'authentic co-construction', in which neither trainer nor trainee appeared certain of what they were seeing and pieced together the information collaboratively. Whether the co-construction activity was guided or authentic appeared to be influenced by case difficulty and trainee seniority. Co-construction was shown to occur verbally, through discussion, and also through non-verbal exchanges in which gestures made with laparoscopic instruments contributed to the co-construction discourse. In the training setting, learning visual cue interpretation occurs in part through co-construction. Co-construction is a pedagogic phenomenon that is well recognised in the context of learning to interpret verbal information. In articulating the features of co-construction in the visual domain, this work enables the development of

Visual perception and medical imaging

International Nuclear Information System (INIS)

Jaffe, C.C.

1985-01-01

Medical imaging represents a particularly distinct discipline for image processing since it uniquely depends on the ''expert observer'' and yet models of the human visual system are totally inadequate at the complex level to allow satisfactory prediction of observer response to a given image modification. An illustration of the difficulties in assessing observer performance is shown by a series of optical illustrations which demonstrate that net cognitive behavior is not readily predictable. Although many of these phenomena are often considered as exceptional visual events, the setting of complex images makes it difficult to entirely exclude at least partial operation of these impairments during performance of the diagnostic medical imaging task

Cross-cultural differences for three visual memory tasks in Brazilian children.

Science.gov (United States)

Santos, F H; Mello, C B; Bueno, O F A; Dellatolas, G

2005-10-01

Norms for three visual memory tasks, including Corsi's block tapping test and the BEM 144 complex figures and visual recognition, were developed for neuropsychological assessment in Brazilian children. The tasks were measured in 127 children ages 7 to 10 years from rural and urban areas of the States of São Paulo and Minas Gerais. Analysis indicated age-related but not sex-related differences. A cross-cultural effect was observed in relation to copying and recall of Complex pictures. Different performances between rural and urban children were noted.

Visual arts training is linked to flexible attention to local and global levels of visual stimuli.

Science.gov (United States)

Chamberlain, Rebecca; Wagemans, Johan

2015-10-01

Observational drawing skill has been shown to be associated with the ability to focus on local visual details. It is unclear whether superior performance in local processing is indicative of the ability to attend to, and flexibly switch between, local and global levels of visual stimuli. It is also unknown whether these attentional enhancements remain specific to observational drawing skill or are a product of a wide range of artistic activities. The current study aimed to address these questions by testing if flexible visual processing predicts artistic group membership and observational drawing skill in a sample of first-year bachelor's degree art students (n=23) and non-art students (n=23). A pattern of local and global visual processing enhancements was found in relation to artistic group membership and drawing skill, with local processing ability found to be specifically related to individual differences in drawing skill. Enhanced global processing and more fluent switching between local and global levels of hierarchical stimuli predicted both drawing skill and artistic group membership, suggesting that these are beneficial attentional mechanisms for art-making in a range of domains. These findings support a top-down attentional model of artistic expertise and shed light on the domain specific and domain-general attentional enhancements induced by proficiency in the visual arts. Copyright © 2015 Elsevier B.V. All rights reserved.

A Review of Research Related to Unmanned Aircraft System Visual Observers

Science.gov (United States)

2014-10-01

simulation of visual detection performance derived from published data. Proceedings of the 2nd International Symposium on Aviation Psychology at the Ohio...State University, 465-471. Gilbert, M. (1950). Colour perception in parafoveal vision. Proceedings of the Physical Society, Section B. 63(2), 83-89

Advances in visual correction and postoperative visual treatment of congenital cataract

Directory of Open Access Journals (Sweden)

Lin Mei

2014-04-01

Full Text Available Congenital cataract is one of the important diseases that cause irreversible visual impairment on children. Compared with adult cataract, the surgery of congenital cataract is more complicated and the complications are more severer, especially the postoperative amblyopia often leads to bad prognosis. Therefore, the postoperative treatment is necessary to obtain the better visual outcome. The traditional visual correction methods after surgery include the combined use of spectacles, contact lens, and intraocular lens(IOL, but some problems such as IOL power calculation and IOL implantation time are still controversial. Besides, occlusion therapy and visual training are also essential for preventing amblyopia after cataract surgery. Occlusion in an appropriate dose and course must be mastered, accompanied by visual training. Both of the operative eyes and normal eyes will be able to achieve much better visual acuity and color sensitivity, so that the binocular vision can recover and develop as normal function.

Visual Working Memory Enhances the Neural Response to Matching Visual Input.

Science.gov (United States)

Gayet, Surya; Guggenmos, Matthias; Christophel, Thomas B; Haynes, John-Dylan; Paffen, Chris L E; Van der Stigchel, Stefan; Sterzer, Philipp

2017-07-12

Visual working memory (VWM) is used to maintain visual information available for subsequent goal-directed behavior. The content of VWM has been shown to affect the behavioral response to concurrent visual input, suggesting that visual representations originating from VWM and from sensory input draw upon a shared neural substrate (i.e., a sensory recruitment stance on VWM storage). Here, we hypothesized that visual information maintained in VWM would enhance the neural response to concurrent visual input that matches the content of VWM. To test this hypothesis, we measured fMRI BOLD responses to task-irrelevant stimuli acquired from 15 human participants (three males) performing a concurrent delayed match-to-sample task. In this task, observers were sequentially presented with two shape stimuli and a retro-cue indicating which of the two shapes should be memorized for subsequent recognition. During the retention interval, a task-irrelevant shape (the probe) was briefly presented in the peripheral visual field, which could either match or mismatch the shape category of the memorized stimulus. We show that this probe stimulus elicited a stronger BOLD response, and allowed for increased shape-classification performance, when it matched rather than mismatched the concurrently memorized content, despite identical visual stimulation. Our results demonstrate that VWM enhances the neural response to concurrent visual input in a content-specific way. This finding is consistent with the view that neural populations involved in sensory processing are recruited for VWM storage, and it provides a common explanation for a plethora of behavioral studies in which VWM-matching visual input elicits a stronger behavioral and perceptual response. SIGNIFICANCE STATEMENT Humans heavily rely on visual information to interact with their environment and frequently must memorize such information for later use. Visual working memory allows for maintaining such visual information in the mind

Modulation of brain activity during action observation: influence of perspective, transitivity and meaningfulness.

Directory of Open Access Journals (Sweden)

Sébastien Hétu

Full Text Available The coupling process between observed and performed actions is thought to be performed by a fronto-parietal perception-action system including regions of the inferior frontal gyrus and the inferior parietal lobule. When investigating the influence of the movements' characteristics on this process, most research on action observation has focused on only one particular variable even though the type of movements we observe can vary on several levels. By manipulating the visual perspective, transitivity and meaningfulness of observed movements in a functional magnetic resonance imaging study we aimed at investigating how the type of movements and the visual perspective can modulate brain activity during action observation in healthy individuals. Importantly, we used an active observation task where participants had to subsequently execute or imagine the observed movements. Our results show that the fronto-parietal regions of the perception action system were mostly recruited during the observation of meaningless actions while visual perspective had little influence on the activity within the perception-action system. Simultaneous investigation of several sources of modulation during active action observation is probably an approach that could lead to a greater ecological comprehension of this important sensorimotor process.

Ultra-scale Visualization Climate Data Analysis Tools (UV-CDAT)

Energy Technology Data Exchange (ETDEWEB)

Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Silva, Claudio [New York Univ. (NYU), NY (United States). Computer Science and Engineering Dept.

2013-09-30

For the past three years, a large analysis and visualization effort—funded by the Department of Energy’s Office of Biological and Environmental Research (BER), the National Aeronautics and Space Administration (NASA), and the National Oceanic and Atmospheric Administration (NOAA)—has brought together a wide variety of industry-standard scientific computing libraries and applications to create Ultra-scale Visualization Climate Data Analysis Tools (UV-CDAT) to serve the global climate simulation and observational research communities. To support interactive analysis and visualization, all components connect through a provenance application–programming interface to capture meaningful history and workflow. Components can be loosely coupled into the framework for fast integration or tightly coupled for greater system functionality and communication with other components. The overarching goal of UV-CDAT is to provide a new paradigm for access to and analysis of massive, distributed scientific data collections by leveraging distributed data architectures located throughout the world. The UV-CDAT framework addresses challenges in analysis and visualization and incorporates new opportunities, including parallelism for better efficiency, higher speed, and more accurate scientific inferences. Today, it provides more than 600 users access to more analysis and visualization products than any other single source.

Visual Restoration after Cataract Surgery Promotes Functional and Structural Brain Recovery

Directory of Open Access Journals (Sweden)

Haotian Lin

2018-04-01

Full Text Available Background: Visual function and brain function decline concurrently with aging. Notably, cataract patients often present with accelerated age-related decreases in brain function, but the underlying mechanisms are still unclear. Optical structures of the anterior segment of the eyes, such as the lens and cornea, can be readily reconstructed to improve refraction and vision quality. However, the effects of visual restoration on human brain function and structure remain largely unexplored. Methods: A prospective, controlled clinical trial was conducted. Twenty-six patients with bilateral age-related cataracts (ARCs who underwent phacoemulsification and intraocular lens implantation and 26 healthy controls without ARC, matched for age, sex, and education, were recruited. Visual functions (including visual acuity, visual evoke potential, and contrast sensitivity, the Mini-Mental State Examination and functional magnetic resonance imaging (including the fractional amplitude of low-frequency fluctuations and grey matter volume variation were assessed for all the participants and reexamined for ARC patients after cataract surgery. This trial was registered with ClinicalTrials.gov (NCT02644720. Findings: Compared with the healthy controls, the ARC patients presented decreased brain functionality as well as structural alterations in visual and cognitive-related brain areas preoperatively. Three months postoperatively, significant functional improvements were observed in the visual and cognitive-related brain areas of the patients. Six months postoperatively, the patients' grey matter volumes in these areas were significantly increased. Notably, both the function and structure in the visual and cognitive-related brain areas of the patients improved significantly and became comparable to those of the healthy controls 6 months postoperatively. Interpretation: We demonstrated that ocular reconstruction can functionally and structurally reverse cataract

The role of primary auditory and visual cortices in temporal processing: A tDCS approach.

Science.gov (United States)

Mioni, G; Grondin, S; Forgione, M; Fracasso, V; Mapelli, D; Stablum, F

2016-10-15

Many studies showed that visual stimuli are frequently experienced as shorter than equivalent auditory stimuli. These findings suggest that timing is distributed across many brain areas and that "different clocks" might be involved in temporal processing. The aim of this study is to investigate, with the application of tDCS over V1 and A1, the specific role of primary sensory cortices (either visual or auditory) in temporal processing. Forty-eight University students were included in the study. Twenty-four participants were stimulated over A1 and 24 participants were stimulated over V1. Participants performed time bisection tasks, in the visual and the auditory modalities, involving standard durations lasting 300ms (short) and 900ms (long). When tDCS was delivered over A1, no effect of stimulation was observed on perceived duration but we observed higher temporal variability under anodic stimulation compared to sham and higher variability in the visual compared to the auditory modality. When tDCS was delivered over V1, an under-estimation of perceived duration and higher variability was observed in the visual compared to the auditory modality. Our results showed more variability of visual temporal processing under tDCS stimulation. These results suggest a modality independent role of A1 in temporal processing and a modality specific role of V1 in the processing of temporal intervals in the visual modality. Copyright © 2016 Elsevier B.V. All rights reserved.

Inter-observer variability of visual analysis of "stress"-only adenosine first-pass myocardial perfusion imaging in relation to clinical experience and reading criteria

NARCIS (Netherlands)

Lubbers, D. D.; Kuijpers, D.; Bodewes, R.; Kappert, P.; Kerkhof, M.; van Ooijen, P. M. A.; Oudkerk, M.

To assess the inter-observer agreement of adenosine "stress"-only visual analysis of perfusion MR images in relation to experience and reading criteria. 106 adenosine perfusion MR examinations out of 350, 46 consecutive positive examinations and 60 randomly selected negative examinations were

Investigation of the metabolic changes in visual cortex due to visual stimulation using high field magnetic resonance spectroscopy at 7.0 T

International Nuclear Information System (INIS)

Lin Yan; Peter, M.; Wu Renhua

2012-01-01

stimulation paradigm and 1 H MRS at 7.0 T and LC Model, the metabolic response to activation have been able to be observed. The observed changes of Asp, Glc and Lac concentrations in response to visual stimulation suggests that sustained neuronal activation raises oxidative metabolism to a new steady state. The observation of increased Glu with decreased Gln during stimulation can be interpreted as a stimulus driven increase in excitatory neurotransmitter cycling. The elevated GSH in the visual cortex in response to visual stimulation is a new observation. Possible explanations for this include detoxification of reactive oxygen species. (authors)

Visual Guided Navigation

National Research Council Canada - National Science Library

Banks, Martin

1999-01-01

.... Similarly, the problem of visual navigation is the recovery of an observer's self-motion with respect to the environment from the moving pattern of light reaching the eyes and the complex of extra...

Visual Basic 2012 programmer's reference

CERN Document Server

Stephens, Rod

2012-01-01

The comprehensive guide to Visual Basic 2012 Microsoft Visual Basic (VB) is the most popular programming language in the world, with millions of lines of code used in businesses and applications of all types and sizes. In this edition of the bestselling Wrox guide, Visual Basic expert Rod Stephens offers novice and experienced developers a comprehensive tutorial and reference to Visual Basic 2012. This latest edition introduces major changes to the Visual Studio development platform, including support for developing mobile applications that can take advantage of the Windows 8 operating system

Visual acuity and visual skills in Malaysian children with learning disabilities

Directory of Open Access Journals (Sweden)

Muzaliha MN

2012-09-01

Full Text Available Mohd-Nor Muzaliha,1 Buang Nurhamiza,1 Adil Hussein,1 Abdul-Rani Norabibas,1 Jaafar Mohd-Hisham-Basrun,1 Abdullah Sarimah,2 Seo-Wei Leo,3 Ismail Shatriah11Department of Ophthalmology, 2Biostatistics and Research Methodology Unit, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia; 3Paediatric Ophthalmology and Strabismus Unit, Department of Ophthalmology, Tan Tock Seng Hospital, SingaporeBackground: There is limited data in the literature concerning the visual status and skills in children with learning disabilities, particularly within the Asian population. This study is aimed to determine visual acuity and visual skills in children with learning disabilities in primary schools within the suburban Kota Bharu district in Malaysia.Methods: We examined 1010 children with learning disabilities aged between 8–12 years from 40 primary schools in the Kota Bharu district, Malaysia from January 2009 to March 2010. These children were identified based on their performance in a screening test known as the Early Intervention Class for Reading and Writing Screening Test conducted by the Ministry of Education, Malaysia. Complete ocular examinations and visual skills assessment included near point of convergence, amplitude of accommodation, accommodative facility, convergence break and recovery, divergence break and recovery, and developmental eye movement tests for all subjects.Results: A total of 4.8% of students had visual acuity worse than 6/12 (20/40, 14.0% had convergence insufficiency, 28.3% displayed poor accommodative amplitude, and 26.0% showed signs of accommodative infacility. A total of 12.1% of the students had poor convergence break, 45.7% displayed poor convergence recovery, 37.4% showed poor divergence break, and 66.3% were noted to have poor divergence recovery. The mean horizontal developmental eye movement was significantly prolonged.Conclusion: Although their visual acuity was satisfactory, nearly 30% of the

Visual observation of gas hydrates nucleation and growth at a water - organic liquid interface

Science.gov (United States)

Stoporev, Andrey S.; Semenov, Anton P.; Medvedev, Vladimir I.; Sizikov, Artem A.; Gushchin, Pavel A.; Vinokurov, Vladimir A.; Manakov, Andrey Yu.

2018-03-01

Visual observation of nucleation sites of methane and methane-ethane-propane hydrates and their further growth in water - organic liquid - gas systems with/without surfactants was carried out. Sapphire Rocking Cell RCS6 with transparent sapphire cells was used. The experiments were conducted at the supercooling ΔTsub = 20.2 °C. Decane, toluene and crude oils were used as organics. Gas hydrate nucleation occurred on water - metal - gas and water - sapphire - organic liquid three-phase contact lines. At the initial stage of growth hydrate crystals rapidly covered the water - gas or water - organics interfaces (depending on the nucleation site). Further hydrate phase accrete on cell walls (sapphire surface) and into the organics volume. At this stage, growth was accompanied by water «drawing out» from under initial hydrate film formed at water - organic interface. Apparently, it takes place due to water capillary inflow in the reaction zone. It was shown that the hydrate crystal morphology depends on the organic phase composition. In the case of water-in-decane emulsion relay hydrate crystallization was observed in the whole sample, originating most likely due to the hydrate crystal intergrowth through decane. Contacts of such crystals with adjacent water droplets result in rapid hydrate crystallization on this droplet.

Visual Representation Determines Search Difficulty: Explaining Visual Search Asymmetries

Directory of Open Access Journals (Sweden)

Neil eBruce

2011-07-01

Full Text Available In visual search experiments there exist a variety of experimental paradigms in which a symmetric set of experimental conditions yields asymmetric corresponding task performance. There are a variety of examples of this that currently lack a satisfactory explanation. In this paper, we demonstrate that distinct classes of asymmetries may be explained by virtue of a few simple conditions that are consistent with current thinking surrounding computational modeling of visual search and coding in the primate brain. This includes a detailed look at the role that stimulus familiarity plays in the determination of search performance. Overall, we demonstrate that all of these asymmetries have a common origin, namely, they are a consequence of the encoding that appears in the visual cortex. The analysis associated with these cases yields insight into the problem of visual search in general and predictions of novel search asymmetries.

The structure of visual spaces

NARCIS (Netherlands)

Koenderink, J.J.; van Doorn, A.J.

2008-01-01

The “visual space” of an optical observer situated at a single, fixed viewpoint is necessarily very ambiguous. Although the structure of the “visual field” (the lateral dimensions, i.e., the “image”) is well defined, the “depth” dimension has to be inferred from the image on the basis of “monocular

Modification of visual function by early visual experience.

Science.gov (United States)

Blakemore, C

1976-07-01

Physiological experiments, involving recording from the visual cortex in young kittens and monkeys, have given new insight into human developmental disorders. In the visual cortex of normal cats and monkeys most neurones are selectively sensitive to the orientation of moving edges and they receive very similar signals from both eyes. Even in very young kittens without visual experience, most neurones are binocularly driven and a small proportion of them are genuinely orientation selective. There is no passive maturation of the system in the absence of visual experience, but even very brief exposure to patterned images produces rapid emergence of the adult organization. These results are compared to observations on humans who have "recovered" from early blindness. Covering one eye in a kitten or a monkey, during a sensitive period early in life, produces a virtually complete loss of input from that eye in the cortex. These results can be correlated with the production of "stimulus deprivation amblyopia" in infants who have had one eye patched. Induction of a strabismus causes a loss of binocularity in the visual cortex, and in humans it leads to a loss of stereoscopic vision and binocular fusion. Exposing kittens to lines of one orientation modifies the preferred orientations of cortical cells and there is an analogous "meridional amblyopia" in astigmatic humans. The existence of a sensitive period in human vision is discussed, as well as the possibility of designing remedial and preventive treatments for human developmental disorders.

Right hemispheric dominance of visual phenomena evoked by intracerebral stimulation of the human visual cortex.

Science.gov (United States)

Jonas, Jacques; Frismand, Solène; Vignal, Jean-Pierre; Colnat-Coulbois, Sophie; Koessler, Laurent; Vespignani, Hervé; Rossion, Bruno; Maillard, Louis

2014-07-01

Electrical brain stimulation can provide important information about the functional organization of the human visual cortex. Here, we report the visual phenomena evoked by a large number (562) of intracerebral electrical stimulations performed at low-intensity with depth electrodes implanted in the occipito-parieto-temporal cortex of 22 epileptic patients. Focal electrical stimulation evoked primarily visual hallucinations with various complexities: simple (spot or blob), intermediary (geometric forms), or complex meaningful shapes (faces); visual illusions and impairments of visual recognition were more rarely observed. With the exception of the most posterior cortical sites, the probability of evoking a visual phenomenon was significantly higher in the right than the left hemisphere. Intermediary and complex hallucinations, illusions, and visual recognition impairments were almost exclusively evoked by stimulation in the right hemisphere. The probability of evoking a visual phenomenon decreased substantially from the occipital pole to the most anterior sites of the temporal lobe, and this decrease was more pronounced in the left hemisphere. The greater sensitivity of the right occipito-parieto-temporal regions to intracerebral electrical stimulation to evoke visual phenomena supports a predominant role of right hemispheric visual areas from perception to recognition of visual forms, regardless of visuospatial and attentional factors. Copyright © 2013 Wiley Periodicals, Inc.

Visual attention capacity

DEFF Research Database (Denmark)

Habekost, Thomas; Starrfelt, Randi

2009-01-01

Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity......, and measurements are highly reliable. As the method is theoretically founded, it also has high validity. TVA-based assessment has recently been used to investigate a broad range of neuropsychological and neurological conditions. We present the method, including the experimental paradigm and practical guidelines...... to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical...

Boundary layer transition observations on a body of revolution with surface heating and cooling in water

Science.gov (United States)

Arakeri, V. H.

1980-04-01

Boundary layer flow visualization in water with surface heat transfer was carried out on a body of revolution which had the predicted possibility of laminar separation under isothermal conditions. Flow visualization was by in-line holographic technique. Boundary layer stabilization, including elimination of laminar separation, was observed to take place on surface heating. Conversely, boundary layer destabilization was observed on surface cooling. These findings are consistent with the theoretical predictions of Wazzan et al. (1970).

Incremental Visualizer for Visible Objects

DEFF Research Database (Denmark)

Bukauskas, Linas; Bøhlen, Michael Hanspeter

This paper discusses the integration of database back-end and visualizer front-end into a one tightly coupled system. The main aim which we achieve is to reduce the data pipeline from database to visualization by using incremental data extraction of visible objects in a fly-through scenarios. We...... also argue that passing only relevant data from the database will substantially reduce the overall load of the visualization system. We propose the system Incremental Visualizer for Visible Objects (IVVO) which considers visible objects and enables incremental visualization along the observer movement...... path. IVVO is the novel solution which allows data to be visualized and loaded on the fly from the database and which regards visibilities of objects. We run a set of experiments to convince that IVVO is feasible in terms of I/O operations and CPU load. We consider the example of data which uses...

Is theta burst stimulation applied to visual cortex able to modulate peripheral visual acuity?

Directory of Open Access Journals (Sweden)

Sabrina Brückner

Full Text Available Repetitive transcranial magnetic stimulation is usually applied to visual cortex to explore the effects on cortical excitability. Most researchers therefore concentrate on changes of phosphene threshold, rarely on consequences for visual performance. Thus, we investigated peripheral visual acuity in the four quadrants of the visual field using Landolt C optotypes before and after repetitive stimulation of the visual cortex. We applied continuous and intermittend theta burst stimulation with various stimulation intensities (60%, 80%, 100%, 120% of individual phosphene threshold as well as monophasic and biphasic 1 Hz stimulation, respectively. As an important result, no serious adverse effects were observed. In particular, no seizure was induced, even with theta burst stimulation applied with 120% of individual phosphene threshold. In only one case stimulation was ceased because the subject reported intolerable pain. Baseline visual acuity decreased over sessions, indicating a continuous training effect. Unexpectedly, none of the applied transcranial magnetic stimulation protocols had an effect on performance: no change in visual acuity was found in any of the four quadrants of the visual field. Binocular viewing as well as the use of peripheral instead of foveal presentation of the stimuli might have contributed to this result. Furthermore, intraindividual variability could have masked the TMS- induced effects on visual acuity.

NASA's Global Imagery Browse Services - Technologies for Visualizing Earth Science Data

Science.gov (United States)

Cechini, M. F.; Boller, R. A.; Baynes, K.; Schmaltz, J. E.; Thompson, C. K.; Roberts, J. T.; Rodriguez, J.; Wong, M. M.; King, B. A.; King, J.; De Luca, A. P.; Pressley, N. N.

2017-12-01

For more than 20 years, the NASA Earth Observing System (EOS) has collected earth science data for thousands of scientific parameters now totaling nearly 15 Petabytes of data. In 2013, NASA's Global Imagery Browse Services (GIBS) formed its vision to "transform how end users interact and discover [EOS] data through visualizations." This vision included leveraging scientific and community best practices and standards to provide a scalable, compliant, and authoritative source for EOS earth science data visualizations. Since that time, GIBS has grown quickly and now services millions of daily requests for over 500 imagery layers representing hundreds of earth science parameters to a broad community of users. For many of these parameters, visualizations are available within hours of acquisition from the satellite. For others, visualizations are available for the entire mission of the satellite. The GIBS system is built upon the OnEarth and MRF open source software projects, which are provided by the GIBS team. This software facilitates standards-based access for compliance with existing GIS tools. The GIBS imagery layers are predominantly rasterized images represented in two-dimensional coordinate systems, though multiple projections are supported. The OnEarth software also supports the GIBS ingest pipeline to facilitate low latency updates to new or updated visualizations. This presentation will focus on the following topics: Overview of GIBS visualizations and user community Current benefits and limitations of the OnEarth and MRF software projects and related standards GIBS access methods and their in/compatibilities with existing GIS libraries and applications Considerations for visualization accuracy and understandability Future plans for more advanced visualization concepts including Vertical Profiles and Vector-Based Representations Future plans for Amazon Web Service support and deployments

New classification system-based visual outcome in Eales′ disease

Directory of Open Access Journals (Sweden)

Saxena Sandeep

2007-01-01

Full Text Available Purpose: A retrospective tertiary care center-based study was undertaken to evaluate the visual outcome in Eales′ disease, based on a new classification system, for the first time. Materials and Methods: One hundred and fifty-nine consecutive cases of Eales′ disease were included. All the eyes were staged according to the new classification: Stage 1: periphlebitis of small (1a and large (1b caliber vessels with superficial retinal hemorrhages; Stage 2a: capillary non-perfusion, 2b: neovascularization elsewhere/of the disc; Stage 3a: fibrovascular proliferation, 3b: vitreous hemorrhage; Stage 4a: traction/combined rhegmatogenous retinal detachment and 4b: rubeosis iridis, neovascular glaucoma, complicated cataract and optic atrophy. Visual acuity was graded as: Grade I 20/20 or better; Grade II 20/30 to 20/40; Grade III 20/60 to 20/120 and Grade IV 20/200 or worse. All the cases were managed by medical therapy, photocoagulation and/or vitreoretinal surgery. Visual acuity was converted into decimal scale, denoting 20/20=1 and 20/800=0.01. Paired t-test / Wilcoxon signed-rank tests were used for statistical analysis. Results: Vitreous hemorrhage was the commonest presenting feature (49.32%. Cases with Stages 1 to 3 and 4a and 4b achieved final visual acuity ranging from 20/15 to 20/40; 20/80 to 20/400 and 20/200 to 20/400, respectively. Statistically significant improvement in visual acuities was observed in all the stages of the disease except Stages 1a and 4b. Conclusion: Significant improvement in visual acuities was observed in the majority of stages of Eales′ disease following treatment. This study adds further to the little available evidences of treatment effects in literature and may have effect on patient care and health policy in Eales′ disease.

Visual sensations induced by relativistic pions

International Nuclear Information System (INIS)

McNulty, P.J.; Pease, V.P.; Bond, V.P.

1976-01-01

Visual sensations were experienced when bursts of high-energy pions passed through the dark-adapted right eyes of three human subjects. The threshold for a visual sensation was typically 1 to 3 μrad at the retina. Data are presented to show that the mechanism is Cerenkov radiation generated within the vitreous humor. Threshold measurements agree with published optical data. A comparison is made between our observations and the light flashes observed in deep space by Apollo astronauts

Visual communication with non-literates: a review of current knowledge including research in northern India.

Science.gov (United States)

Moynihan, M; Mukherjee, U

1981-01-01

In this article previous research on the perception of visual aids by non-literates in Kenya, Zambia, Ghana, Papua New Guinea, Mexico, as well as among immigrant groups in London and Paris, in Nepal and, by the authors in northern India, is reviewed. Recognition of pictures is affected by the particular culture of each group. In Africa, photos are better understood and liked: in the Indian subcontinent, line drawings are well recognized and appreciated. Recognition can be reduced by inaccurate detail, stylization and perspective. The authors found that overall size could be kept small if the pictures were simple. Complicated pictures, or a group of interrelated pictures, are not usually well recognized. Familiarity, realism and simplicity seem the most important components for a successful picture. Ways of attaching value ("good" or "bad", for example) have not in the past been very successful, but the authors found that a "vocabulary" of fourteen signs were, once explained, well understood. The values of colours in the culture must be understood and utilized. To be successful, visual materials for non-literates must start from the local culture and not come untested from behind a desk in the capital city.

Reconfigurable Auditory-Visual Display

Science.gov (United States)

Begault, Durand R. (Inventor); Anderson, Mark R. (Inventor); McClain, Bryan (Inventor); Miller, Joel D. (Inventor)

2008-01-01

System and method for visual and audible communication between a central operator and N mobile communicators (N greater than or equal to 2), including an operator transceiver and interface, configured to receive and display, for the operator, visually perceptible and audibly perceptible signals from each of the mobile communicators. The interface (1) presents an audible signal from each communicator as if the audible signal is received from a different location relative to the operator and (2) allows the operator to select, to assign priority to, and to display, the visual signals and the audible signals received from a specified communicator. Each communicator has an associated signal transmitter that is configured to transmit at least one of the visual signals and the audio signal associated with the communicator, where at least one of the signal transmitters includes at least one sensor that senses and transmits a sensor value representing a selected environmental or physiological parameter associated with the communicator.

Generating descriptive visual words and visual phrases for large-scale image applications.

Science.gov (United States)

Zhang, Shiliang; Tian, Qi; Hua, Gang; Huang, Qingming; Gao, Wen

2011-09-01

Bag-of-visual Words (BoWs) representation has been applied for various problems in the fields of multimedia and computer vision. The basic idea is to represent images as visual documents composed of repeatable and distinctive visual elements, which are comparable to the text words. Notwithstanding its great success and wide adoption, visual vocabulary created from single-image local descriptors is often shown to be not as effective as desired. In this paper, descriptive visual words (DVWs) and descriptive visual phrases (DVPs) are proposed as the visual correspondences to text words and phrases, where visual phrases refer to the frequently co-occurring visual word pairs. Since images are the carriers of visual objects and scenes, a descriptive visual element set can be composed by the visual words and their combinations which are effective in representing certain visual objects or scenes. Based on this idea, a general framework is proposed for generating DVWs and DVPs for image applications. In a large-scale image database containing 1506 object and scene categories, the visual words and visual word pairs descriptive to certain objects or scenes are identified and collected as the DVWs and DVPs. Experiments show that the DVWs and DVPs are informative and descriptive and, thus, are more comparable with the text words than the classic visual words. We apply the identified DVWs and DVPs in several applications including large-scale near-duplicated image retrieval, image search re-ranking, and object recognition. The combination of DVW and DVP performs better than the state of the art in large-scale near-duplicated image retrieval in terms of accuracy, efficiency and memory consumption. The proposed image search re-ranking algorithm: DWPRank outperforms the state-of-the-art algorithm by 12.4% in mean average precision and about 11 times faster in efficiency.

Visual Memory of Meaningless Shapes in Children and Adolescents with Autism Spectrum Disorders

Directory of Open Access Journals (Sweden)

Maryam Salmanian

2012-09-01

Full Text Available objective: Visual memory is an important cognitive ability, which has been studied in individuals with Autism Spectrum Disorders (ASDs. In such studies meaningful shapes were used more frequently. Since meaningless shapes provide a better assessment of short term visual memory, in this study we used them to evaluate visual memory in children and adolescents with ASDs compared to the normal group.Methods: Four visual memory tests of Cambridge Neuropsychological Test Automated Battery (CANTAB including Paired Associates Learning (PAL, Pattern Recognition Memory (PRM, Spatial Recognition Memory (SRM and Delayed Matching to Sample (DMS were administered to 15 children and adolescents with ASDs (high functioning autism and Asperger syndrome and to 15 normal participants aged 8 to 17,with IQ of above 70.Results: Individuals with ASDs performed worse than the normal group on visual memory tasks. After eliminating IQ as a covariate, no significant difference was observed between the two groups in terms of visual memory performance.Conclusion: It seems that deficits on visual memory tasks in youths with ASDs could be related to their general intellectual abilities.

Visual compatibility of defibrotide with selected drugs during simulated Y-site administration.

Science.gov (United States)

Correard, Florian; Savry, Amandine; Gauthier-Villano, Laurence; Pisano, Pascale; Pourroy, Bertrand

2014-08-01

The visual compatibility of a solution of defibrotide (the only drug recommended for treatment and prophylaxis of hepatic venoocclusive disease) with solutions of various drugs commonly administered in bone marrow transplant procedures was studied. Solutions of 43 drug products in concentrations typically used in clinical practice were evaluated in 1:1 mixtures with defibrotide solution in glass tubes kept at room temperature. The evaluated products included antiinfectious, corticoid, sedative, analgesic, and cardiovascular agents widely used for hematopoietic stem cell transplantation and other marrow transplant procedures; in most cases, test solutions were prepared via dilution in or reconstitution with sterile water, 0.9% sodium chloride injection, or 5% dextrose injection. The mixtures were visually observed immediately after manual mixing and at specified time points (60, 150, and 240 minutes). Visual compatibility was defined as the absence of color change, haze, fibers, particles, gas generation, and precipitate formation. The effect of mixing order on visual compatibility was ascertained. Of the 43 tested drug solutions, 36 were found to be visually compatible with the defibrotide solution over the entire four-hour study period. Solutions of 7 drugs (amikacin, furosemide, midazolam, mycophenolate mofetil, nicardipine, tobramycin, and vancomycin) were visually incompatible with defibrotide solution. In some cases, evidence of incompatibility was observed intermittently or was dependent on mixing order. Defibrotide solution was found to be visually compatible with solutions of 36 i.v. products that are likely to be coadministered with the drug in a bone marrow transplant unit. Seven drug solutions were visually incompatible with defibrotide solution. Copyright © 2014 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Gambling in the visual periphery: a conjoint-measurement analysis of human ability to judge visual uncertainty.

Directory of Open Access Journals (Sweden)

Hang Zhang

Full Text Available Recent work in motor control demonstrates that humans take their own motor uncertainty into account, adjusting the timing and goals of movement so as to maximize expected gain. Visual sensitivity varies dramatically with retinal location and target, and models of optimal visual search typically assume that the visual system takes retinal inhomogeneity into account in planning eye movements. Such models can then use the entire retina rather than just the fovea to speed search. Using a simple decision task, we evaluated human ability to compensate for retinal inhomogeneity. We first measured observers' sensitivity for targets, varying contrast and eccentricity. Observers then repeatedly chose between targets differing in eccentricity and contrast, selecting the one they would prefer to attempt: e.g., a low contrast target at 2° versus a high contrast target at 10°. Observers knew they would later attempt some of their chosen targets and receive rewards for correct classifications. We evaluated performance in three ways. Equivalence: Do observers' judgments agree with their actual performance? Do they correctly trade off eccentricity and contrast and select the more discriminable target in each pair? Transitivity: Are observers' choices self-consistent? Dominance: Do observers understand that increased contrast improves performance? Decreased eccentricity? All observers exhibited patterned failures of equivalence, and seven out of eight observers failed transitivity. There were significant but small failures of dominance. All these failures together reduced their winnings by 10%-18%.

A visual description of 2-component spinor calculus

International Nuclear Information System (INIS)

Hellsten, H.

1975-07-01

Spinors and algebraic operations on them are given a visual description. This structural interpretation of spinors is to be contrasted with the well known quadratic relation between spinors and visual objects (vectors,flagpoles). The interpretation in the present paper is founded on the observation that the product between two successive rotations half a turn along the legs of an angle will be a rotation through twice that angle. This observation makes it possible to explain visually the doubling of angles, which occurs when vectors are constructed out of spinors. It is seen that, using this explanation, spinor calculus can, in close analogy to 3-dimensional Euclidean vector calculus, be given a purely visual meaning. (Auth.)

A device for emergency cooling visualization

International Nuclear Information System (INIS)

Rezende, Hugo Cesar; Ladeira, Luiz Carlos Duarte

1995-01-01

A test facility for rewetting experiments, Emergency Cooling Visualization Device, has been erected at CDTN, with the objective of Emergency Cooling visualization device performing visual observations of basic phenomena that occur during the reflood phase of a Loss of Coolant Accident (LOCA), in a Pressurised Water Reactor (PWR), utilizing annular test sections. It permits to film or photograph the advance of a wetting front and the flow and heat transfer conditions. Then it is possible to observe the heat transfer regions and flow zones: steam convection, fog cooling, film boiling, nucleate boiling and fluid convection. Finally, this facility is the first test facility, in the Thermohydraulics Laboratory of CDTN, that uses a indirectly heated fuel rod simulator. (author). 3 refs, 5 figs

The T?lz Temporal Topography Study: Mapping the visual field across the life span. Part II: Cognitive factors shaping visual field maps

OpenAIRE

Poggel, Dorothe A.; Treutwein, Bernhard; Calmanti, Claudia; Strasburger, Hans

2012-01-01

Part I described the topography of visual performance over the life span. Performance decline was explained only partly by deterioration of the optical apparatus. Part II therefore examines the influence of higher visual and cognitive functions. Visual field maps for 95 healthy observers of static perimetry, double-pulse resolution (DPR), reaction times, and contrast thresholds, were correlated with measures of visual attention (alertness, divided attention, spatial cueing), visual search, an...

High-intensity erotic visual stimuli de-activate the primary visual cortex in women.

Science.gov (United States)

Huynh, Hieu K; Beers, Caroline; Willemsen, Antoon; Lont, Erna; Laan, Ellen; Dierckx, Rudi; Jansen, Monique; Sand, Michael; Weijmar Schultz, Willibrord; Holstege, Gert

2012-06-01

The primary visual cortex, Brodmann's area (BA 17), plays a vital role in basic survival mechanisms in humans. In most neuro-imaging studies in which the volunteers have to watch pictures or movies, the primary visual cortex is similarly activated independent of the content of the pictures or movies. However, in case the volunteers perform demanding non-visual tasks, the primary visual cortex becomes de-activated, although the amount of incoming visual sensory information is the same. Do low- and high-intensity erotic movies, compared to neutral movies, produce similar de-activation of the primary visual cortex? Brain activation/de-activation was studied by Positron Emission Tomography scanning of the brains of 12 healthy heterosexual premenopausal women, aged 18-47, who watched neutral, low- and high-intensity erotic film segments. We measured differences in regional cerebral blood flow (rCBF) in the primary visual cortex during watching neutral, low-intensity erotic, and high-intensity erotic film segments. Watching high-intensity erotic, but not low-intensity erotic movies, compared to neutral movies resulted in strong de-activation of the primary (BA 17) and adjoining parts of the secondary visual cortex. The strong de-activation during watching high-intensity erotic film might represent compensation for the increased blood supply in the brain regions involved in sexual arousal, also because high-intensity erotic movies do not require precise scanning of the visual field, because the impact is clear to the observer. © 2012 International Society for Sexual Medicine.

Observational constraint on the interacting dark energy models including the Sandage-Loeb test

Science.gov (United States)

Zhang, Ming-Jian; Liu, Wen-Biao

2014-05-01

Two types of interacting dark energy models are investigated using the type Ia supernova (SNIa), observational data (OHD), cosmic microwave background shift parameter, and the secular Sandage-Loeb (SL) test. In the investigation, we have used two sets of parameter priors including WMAP-9 and Planck 2013. They have shown some interesting differences. We find that the inclusion of SL test can obviously provide a more stringent constraint on the parameters in both models. For the constant coupling model, the interaction term has been improved to be only a half of the original scale on corresponding errors. Comparing with only SNIa and OHD, we find that the inclusion of the SL test almost reduces the best-fit interaction to zero, which indicates that the higher-redshift observation including the SL test is necessary to track the evolution of the interaction. For the varying coupling model, data with the inclusion of the SL test show that the parameter at C.L. in Planck priors is , where the constant is characteristic for the severity of the coincidence problem. This indicates that the coincidence problem will be less severe. We then reconstruct the interaction , and we find that the best-fit interaction is also negative, similar to the constant coupling model. However, for a high redshift, the interaction generally vanishes at infinity. We also find that the phantom-like dark energy with is favored over the CDM model.

Sensitivity to the visual field origin of natural image patches in human low-level visual cortex

Directory of Open Access Journals (Sweden)

Damien J. Mannion

2015-06-01

Full Text Available Asymmetries in the response to visual patterns in the upper and lower visual fields (above and below the centre of gaze have been associated with ecological factors relating to the structure of typical visual environments. Here, we investigated whether the content of the upper and lower visual field representations in low-level regions of human visual cortex are specialised for visual patterns that arise from the upper and lower visual fields in natural images. We presented image patches, drawn from above or below the centre of gaze of an observer navigating a natural environment, to either the upper or lower visual fields of human participants (n = 7 while we used functional magnetic resonance imaging (fMRI to measure the magnitude of evoked activity in the visual areas V1, V2, and V3. We found a significant interaction between the presentation location (upper or lower visual field and the image patch source location (above or below fixation; the responses to lower visual field presentation were significantly greater for image patches sourced from below than above fixation, while the responses in the upper visual field were not significantly different for image patches sourced from above and below fixation. This finding demonstrates an association between the representation of the lower visual field in human visual cortex and the structure of the visual input that is likely to be encountered below the centre of gaze.

Visual problems associated with traumatic brain injury.

Science.gov (United States)

Armstrong, Richard A

2018-02-28

Traumatic brain injury (TBI) and its associated concussion are major causes of disability and death. All ages can be affected but children, young adults and the elderly are particularly susceptible. A decline in mortality has resulted in many more individuals living with a disability caused by TBI including those affecting vision. This review describes: (1) the major clinical and pathological features of TBI; (2) the visual signs and symptoms associated with the disorder; and (3) discusses the assessment of quality of life and visual rehabilitation of the patient. Defects in primary vision such as visual acuity and visual fields, eye movement including vergence, saccadic and smooth pursuit movements, and in more complex aspects of vision involving visual perception, motion vision ('akinopsia'), and visuo-spatial function have all been reported in TBI. Eye movement dysfunction may be an early sign of TBI. Hence, TBI can result in a variety of visual problems, many patients exhibiting multiple visual defects in combination with a decline in overall health. Patients with chronic dysfunction following TBI may require occupational, vestibular, cognitive and other forms of physical therapy. Such patients may also benefit from visual rehabilitation, including reading-related oculomotor training and the prescribing of spectacles with a variety of tints and prism combinations. © 2018 Optometry Australia.

Does Differential Visual Exploration Contribute to Visual Memory Impairments in 22Q11.2 Microdeletion Syndrome?

Science.gov (United States)

Bostelmann, M.; Glaser, B.; Zaharia, A.; Eliez, S.; Schneider, M.

2017-01-01

Background: Chromosome 22q11.2 microdeletion syndrome (22q11.2DS) is a genetic syndrome characterised by a unique cognitive profile. Individuals with the syndrome present several non-verbal deficits, including visual memory impairments and atypical exploration of visual information. In this study, we seek to understand how visual attention may…

Observation and visualization: reflections on the relationship between science, visual arts, and the evolution of the scientific image.

Science.gov (United States)

Kolijn, Eveline

2013-10-01

The connections between biological sciences, art and printed images are of great interest to the author. She reflects on the historical relevance of visual representations for science. She argues that the connection between art and science seems to have diminished during the twentieth century. However, this connection is currently growing stronger again through digital media and new imaging methods. Scientific illustrations have fuelled art, while visual modeling tools have assisted scientific research. As a print media artist, she explores the relationship between art and science in her studio practice and will present this historical connection with examples related to evolution, microbiology and her own work. Art and science share a common source, which leads to scrutiny and enquiry. Science sets out to reveal and explain our reality, whereas art comments and makes connections that don't need to be tested by rigorous protocols. Art and science should each be evaluated on their own merit. Allowing room for both in the quest to understand our world will lead to an enriched experience.

Effects of auditory vection speed and directional congruence on perceptions of visual vection

Science.gov (United States)

Gagliano, Isabella Alexis

Spatial disorientation is a major contributor to aircraft mishaps. One potential contributing factor is vection, an illusion of self-motion. Although vection is commonly thought of as a visual illusion, it can also be produced through audition. The purpose of the current experiment was to explore interactions between conflicting visual and auditory vection cues, specifically with regard to the speed and direction of rotation. The ultimate goal was to explore the extent to which aural vection could diminish or enhance the perception of visual vection. The study used a 3 x 2 within-groups factorial design. Participants were exposed to three levels of aural rotation velocity (slower, matched, and faster, relative to visual rotation speed) and two levels of aural rotational congruence (congruent or incongruent rotation) including two control conditions (visual and aural-only). Dependent measures included vection onset time, vection direction judgements, subjective vection strength ratings, vection speed ratings, and horizontal nystagmus frequency. Subjective responses to motion were assessed pre and post treatment, and oculomotor responses were assessed before, during, and following exposure to circular vection. The results revealed a significant effect of stimulus condition on vection strength. Specifically, directionally-congruent aural-visual vection resulted in significantly stronger vection than visual and aural vection alone. Perceptions of directionally-congruent aural-visual vection were slightly stronger vection than directionally-incongruent aural-visual vection, but not significantly so. No significant effects of aural rotation velocity on vection strength were observed. The results suggest directionally-incongruent aural vection could be used as a countermeasure for visual vection and directionally-congruent aural vection could be used to improve vection in virtual environments, provided further research is done.

The Reappearance of Venus Observed 8 October 2015

Science.gov (United States)

Dunham, David W.; Dunham, Joan B.

2018-01-01

The reappearance of Venus on October 8, 2015 offered a unique opportunity to attempt observation of the ashen light of Venus as the unlit side of Venus emerged from behind the dark side of the Moon. The dark side of Venus would be offered to observers without interference from the bright side of Venus or of the Moon. Observations were made from Alice Springs, Australia visually with a 20-cm Schmidt-Cassegrain and with a low-light level surveillance camera on a 25-cm reflector. No evidence of the dark side was noted by the visual observer, the video shows little indication of Venus prior to the bright side reappearance. The conclusion reached is that the ashen light, as it was classically defined, is not observable visually or with small telescopes in the visual regime.The presentation describes the prediction, observation technique, and various analyses by the authors and others to draw conclusions from the data.To date, the authors have been unable to locate any reports of others attempting to observe this unique event. That is a pity since, not only was it interesting for an attempt to verify past observations of the ashen light, it was also a visually stunning event.

Temporal windows in visual processing: "prestimulus brain state" and "poststimulus phase reset" segregate visual transients on different temporal scales.

Science.gov (United States)

Wutz, Andreas; Weisz, Nathan; Braun, Christoph; Melcher, David

2014-01-22

Dynamic vision requires both stability of the current perceptual representation and sensitivity to the accumulation of sensory evidence over time. Here we study the electrophysiological signatures of this intricate balance between temporal segregation and integration in vision. Within a forward masking paradigm with short and long stimulus onset asynchronies (SOA), we manipulated the temporal overlap of the visual persistence of two successive transients. Human observers enumerated the items presented in the second target display as a measure of the informational capacity read-out from this partly temporally integrated visual percept. We observed higher β-power immediately before mask display onset in incorrect trials, in which enumeration failed due to stronger integration of mask and target visual information. This effect was timescale specific, distinguishing between segregation and integration of visual transients that were distant in time (long SOA). Conversely, for short SOA trials, mask onset evoked a stronger visual response when mask and targets were correctly segregated in time. Examination of the target-related response profile revealed the importance of an evoked α-phase reset for the segregation of those rapid visual transients. Investigating this precise mapping of the temporal relationships of visual signals onto electrophysiological responses highlights how the stream of visual information is carved up into discrete temporal windows that mediate between segregated and integrated percepts. Fragmenting the stream of visual information provides a means to stabilize perceptual events within one instant in time.

Visual search among items of different salience: removal of visual attention mimics a lesion in extrastriate area V4.

Science.gov (United States)

Braun, J

1994-02-01

In more than one respect, visual search for the most salient or the least salient item in a display are different kinds of visual tasks. The present work investigated whether this difference is primarily one of perceptual difficulty, or whether it is more fundamental and relates to visual attention. Display items of different salience were produced by varying either size, contrast, color saturation, or pattern. Perceptual masking was employed and, on average, mask onset was delayed longer in search for the least salient item than in search for the most salient item. As a result, the two types of visual search presented comparable perceptual difficulty, as judged by psychophysical measures of performance, effective stimulus contrast, and stability of decision criterion. To investigate the role of attention in the two types of search, observers attempted to carry out a letter discrimination and a search task concurrently. To discriminate the letters, observers had to direct visual attention at the center of the display and, thus, leave unattended the periphery, which contained target and distractors of the search task. In this situation, visual search for the least salient item was severely impaired while visual search for the most salient item was only moderately affected, demonstrating a fundamental difference with respect to visual attention. A qualitatively identical pattern of results was encountered by Schiller and Lee (1991), who used similar visual search tasks to assess the effect of a lesion in extrastriate area V4 of the macaque.

Visualization of ocean forecast in BYTHOS

Science.gov (United States)

Zhuk, E.; Zodiatis, G.; Nikolaidis, A.; Stylianou, S.; Karaolia, A.

2016-08-01

The Cyprus Oceanography Center has been constantly searching for new ideas for developing and implementing innovative methods and new developments concerning the use of Information Systems in Oceanography, to suit both the Center's monitoring and forecasting products. Within the frame of this scope two major online managing and visualizing data systems have been developed and utilized, those of CYCOFOS and BYTHOS. The Cyprus Coastal Ocean Forecasting and Observing System - CYCOFOS provides a variety of operational predictions such as ultra high, high and medium resolution ocean forecasts in the Levantine Basin, offshore and coastal sea state forecasts in the Mediterranean and Black Sea, tide forecasting in the Mediterranean, ocean remote sensing in the Eastern Mediterranean and coastal and offshore monitoring. As a rich internet application, BYTHOS enables scientists to search, visualize and download oceanographic data online and in real time. The recent improving of BYTHOS system is the extension with access and visualization of CYCOFOS data and overlay forecast fields and observing data. The CYCOFOS data are stored at OPENDAP Server in netCDF format. To search, process and visualize it the php and python scripts were developed. Data visualization is achieved through Mapserver. The BYTHOS forecast access interface allows to search necessary forecasting field by recognizing type, parameter, region, level and time. Also it provides opportunity to overlay different forecast and observing data that can be used for complex analyze of sea basin aspects.

Integration of auditory and visual speech information

NARCIS (Netherlands)

Hall, M.; Smeele, P.M.T.; Kuhl, P.K.

1998-01-01

The integration of auditory and visual speech is observed when modes specify different places of articulation. Influences of auditory variation on integration were examined using consonant identifi-cation, plus quality and similarity ratings. Auditory identification predicted auditory-visual

Synthetic Biology Open Language Visual (SBOL Visual) Version 2.0

KAUST Repository

Cox, Robert Sidney

2018-03-24

People who are engineering biological organisms often find it useful to communicate in diagrams, both about the structure of the nucleic acid sequences that they are engineering and about the functional relationships between sequence features and other molecular species. Some typical practices and conventions have begun to emerge for such diagrams. The Synthetic Biology Open Language Visual (SBOL Visual) has been developed as a standard for organizing and systematizing such conventions in order to produce a coherent language for expressing the structure and function of genetic designs. This document details version 2.0 of SBOL Visual, which builds on the prior SBOL Visual 1.0 standard by expanding diagram syntax to include functional interactions and molecular species, making the relationship between diagrams and the SBOL data model explicit, supporting families of symbol variants, clarifying a number of requirements and best practices, and significantly expanding the collection of diagram glyphs.

Immersive Visual Data Analysis For Geoscience Using Commodity VR Hardware

Science.gov (United States)

Kreylos, O.; Kellogg, L. H.

2017-12-01

Immersive visualization using virtual reality (VR) display technology offers tremendous benefits for the visual analysis of complex three-dimensional data like those commonly obtained from geophysical and geological observations and models. Unlike "traditional" visualization, which has to project 3D data onto a 2D screen for display, VR can side-step this projection and display 3D data directly, in a pseudo-holographic (head-tracked stereoscopic) form, and does therefore not suffer the distortions of relative positions, sizes, distances, and angles that are inherent in 2D projection. As a result, researchers can apply their spatial reasoning skills to virtual data in the same way they can to real objects or environments. The UC Davis W.M. Keck Center for Active Visualization in the Earth Sciences (KeckCAVES, http://keckcaves.org) has been developing VR methods for data analysis since 2005, but the high cost of VR displays has been preventing large-scale deployment and adoption of KeckCAVES technology. The recent emergence of high-quality commodity VR, spearheaded by the Oculus Rift and HTC Vive, has fundamentally changed the field. With KeckCAVES' foundational VR operating system, Vrui, now running natively on the HTC Vive, all KeckCAVES visualization software, including 3D Visualizer, LiDAR Viewer, Crusta, Nanotech Construction Kit, and ProtoShop, are now available to small labs, single researchers, and even home users. LiDAR Viewer and Crusta have been used for rapid response to geologic events including earthquakes and landslides, to visualize the impacts of sealevel rise, to investigate reconstructed paleooceanographic masses, and for exploration of the surface of Mars. The Nanotech Construction Kit is being used to explore the phases of carbon in Earth's deep interior, while ProtoShop can be used to construct and investigate protein structures.

Design for Visual Arts.

Science.gov (United States)

Skeries, Larry

Experiences suggested within this visual arts packet provide high school students with awareness of visual expression in graphic design, product design, architecture, and crafts. The unit may be used in whole or in part and includes information about art careers and art-related jobs found in major occupational fields. Specific lesson topics…

Learning Visual Basic NET

CERN Document Server

Liberty, Jesse

2009-01-01

Learning Visual Basic .NET is a complete introduction to VB.NET and object-oriented programming. By using hundreds of examples, this book demonstrates how to develop various kinds of applications--including those that work with databases--and web services. Learning Visual Basic .NET will help you build a solid foundation in .NET.

Visual disability rates in a ten-year cohort of patients with anterior visual pathway meningiomas.

Science.gov (United States)

Bor-Shavit, Elite; Hammel, Naama; Nahum, Yoav; Rappaport, Zvi Harry; Stiebel-Kalish, Hadas

2015-01-01

To examine the visual outcome of anterior visual pathway meningioma (AVPM) patients followed for at least one year. Data were collected on demographics, clinical course and management. Visual disability was classified at the first and last examination as follows: I--no visual disability; II--mild visual defect in one eye; III--mild visual defect in both eyes; IV--loss of driver's license; V--legally blind. Eight-one AVPM patients had their tumor originate in the clinoid process in 23 (28%), sphenoid-wing area in 18 (22%), cavernous sinus in 15 (19%), tuberculum sellae in 8 (10%), and mixed in 17 (21%). On last examination, 46 patients (57%) had good visual acuity in one or both eyes (Class I or II) and 17 (21%) were mildly affected in both eyes. The rate of Class IV disability was 16%, and Class V disability was 6%. Attention needs to be addressed to the considerable proportion of patients with AVPM (22% in this study) who may lose their driver's license or become legally blind. Occupational therapists should play an important role in the multidisciplinary management of those patients to help them adapt to their new physical and social situation. Anterior visual pathway meningiomas (AVPMs) are commonly not life-threatening but they can lead to profound visual disability, especially when the tumor originates in the tuberculum sellae and cavernous sinus. Particular attention should be paid to visual acuity and visual field deficits, as these can profoundly affect the patient's quality of life including ability to drive and activities of daily living. The interdisciplinary management of patients with AVPM should include the neurosurgeon, neuro-ophthalmologist and occupational therapist. Also, early intervention by the occupational therapist can help patients adapt to their current physical and social situation and return to everyday tasks more rapidly.

Do the Contents of Visual Working Memory Automatically Influence Attentional Selection During Visual Search?

OpenAIRE

Woodman, Geoffrey F.; Luck, Steven J.

2007-01-01

In many theories of cognition, researchers propose that working memory and perception operate interactively. For example, in previous studies researchers have suggested that sensory inputs matching the contents of working memory will have an automatic advantage in the competition for processing resources. The authors tested this hypothesis by requiring observers to perform a visual search task while concurrently maintaining object representations in visual working memory. The hypothesis that ...

Visual working memory contaminates perception.

Science.gov (United States)

Kang, Min-Suk; Hong, Sang Wook; Blake, Randolph; Woodman, Geoffrey F

2011-10-01

Indirect evidence suggests that the contents of visual working memory may be maintained within sensory areas early in the visual hierarchy. We tested this possibility using a well-studied motion repulsion phenomenon in which perception of one direction of motion is distorted when another direction of motion is viewed simultaneously. We found that observers misperceived the actual direction of motion of a single motion stimulus if, while viewing that stimulus, they were holding a different motion direction in visual working memory. Control experiments showed that none of a variety of alternative explanations could account for this repulsion effect induced by working memory. Our findings provide compelling evidence that visual working memory representations directly interact with the same neural mechanisms as those involved in processing basic sensory events.

The behavioral context of visual displays in common marmosets (Callithrix jacchus).

Science.gov (United States)

de Boer, Raïssa A; Overduin-de Vries, Anne M; Louwerse, Annet L; Sterck, Elisabeth H M

2013-11-01

Communication is important in social species, and may occur with the use of visual, olfactory or auditory signals. However, visual communication may be hampered in species that are arboreal have elaborate facial coloring and live in small groups. The common marmoset fits these criteria and may have limited visual communication. Nonetheless, some (contradictive) propositions concerning visual displays in the common marmoset have been made, yet quantitative data are lacking. The aim of this study was to assign a behavioral context to different visual displays using pre-post-event-analyses. Focal observations were conducted on 16 captive adult and sub-adult marmosets in three different family groups. Based on behavioral elements with an unambiguous meaning, four different behavioral contexts were distinguished: aggression, fear, affiliation, and play behavior. Visual displays concerned behavior that included facial expressions, body postures, and pilo-erection of the fur. Visual displays related to aggression, fear, and play/affiliation were consistent with the literature. We propose that the visual display "pilo-erection tip of tail" is related to fear. Individuals receiving these fear signals showed a higher rate of affiliative behavior. This study indicates that several visual displays may provide cues or signals of particular social contexts. Since the three displays of fear elicited an affiliative response, they may communicate a request of anxiety reduction or signal an external referent. Concluding, common marmosets, despite being arboreal and living in small groups, use several visual displays to communicate with conspecifics and their facial coloration may not hamper, but actually promote the visibility of visual displays. © 2013 Wiley Periodicals, Inc.

A Prospective Curriculum Using Visual Literacy.

Science.gov (United States)

Hortin, John A.

This report describes the uses of visual literacy programs in the schools and outlines four categories for incorporating training in visual thinking into school curriculums as part of the back to basics movement in education. The report recommends that curriculum writers include materials pertaining to: (1) reading visual language and…

Development of a Computerized Visual Search Test

Science.gov (United States)

Reid, Denise; Babani, Harsha; Jon, Eugenia

2009-01-01

Visual attention and visual search are the features of visual perception, essential for attending and scanning one's environment while engaging in daily occupations. This study describes the development of a novel web-based test of visual search. The development information including the format of the test will be described. The test was designed…

CRITICISM OF VISUAL EXPRESSIONS: THE META-COGNITIVE ...

African Journals Online (AJOL)

Dr. Mangiri

cannot be gathered simply from observing the work of art itself.” They conclude ... The theories of Visual Expression state how people should think and judge visual expressions. ... look like what they have seen in the real world. They consider ...

An imprecise Dirichlet model for Bayesian analysis of failure data including right-censored observations

International Nuclear Information System (INIS)

Coolen, F.P.A.

1997-01-01

This paper is intended to make researchers in reliability theory aware of a recently introduced Bayesian model with imprecise prior distributions for statistical inference on failure data, that can also be considered as a robust Bayesian model. The model consists of a multinomial distribution with Dirichlet priors, making the approach basically nonparametric. New results for the model are presented, related to right-censored observations, where estimation based on this model is closely related to the product-limit estimator, which is an important statistical method to deal with reliability or survival data including right-censored observations. As for the product-limit estimator, the model considered in this paper aims at not using any information other than that provided by observed data, but our model fits into the robust Bayesian context which has the advantage that all inferences can be based on probabilities or expectations, or bounds for probabilities or expectations. The model uses a finite partition of the time-axis, and as such it is also related to life-tables

Similarity relations in visual search predict rapid visual categorization

Science.gov (United States)

Mohan, Krithika; Arun, S. P.

2012-01-01

How do we perform rapid visual categorization?It is widely thought that categorization involves evaluating the similarity of an object to other category items, but the underlying features and similarity relations remain unknown. Here, we hypothesized that categorization performance is based on perceived similarity relations between items within and outside the category. To this end, we measured the categorization performance of human subjects on three diverse visual categories (animals, vehicles, and tools) and across three hierarchical levels (superordinate, basic, and subordinate levels among animals). For the same subjects, we measured their perceived pair-wise similarities between objects using a visual search task. Regardless of category and hierarchical level, we found that the time taken to categorize an object could be predicted using its similarity to members within and outside its category. We were able to account for several classic categorization phenomena, such as (a) the longer times required to reject category membership; (b) the longer times to categorize atypical objects; and (c) differences in performance across tasks and across hierarchical levels. These categorization times were also accounted for by a model that extracts coarse structure from an image. The striking agreement observed between categorization and visual search suggests that these two disparate tasks depend on a shared coarse object representation. PMID:23092947

Activation of serotonin 2A receptors underlies the psilocybin-induced effects on α oscillations, N170 visual-evoked potentials, and visual hallucinations.

Science.gov (United States)

Kometer, Michael; Schmidt, André; Jäncke, Lutz; Vollenweider, Franz X

2013-06-19

Visual illusions and hallucinations are hallmarks of serotonergic hallucinogen-induced altered states of consciousness. Although the serotonergic hallucinogen psilocybin activates multiple serotonin (5-HT) receptors, recent evidence suggests that activation of 5-HT2A receptors may lead to the formation of visual hallucinations by increasing cortical excitability and altering visual-evoked cortical responses. To address this hypothesis, we assessed the effects of psilocybin (215 μg/kg vs placebo) on both α oscillations that regulate cortical excitability and early visual-evoked P1 and N170 potentials in healthy human subjects. To further disentangle the specific contributions of 5-HT2A receptors, subjects were additionally pretreated with the preferential 5-HT2A receptor antagonist ketanserin (50 mg vs placebo). We found that psilocybin strongly decreased prestimulus parieto-occipital α power values, thus precluding a subsequent stimulus-induced α power decrease. Furthermore, psilocybin strongly decreased N170 potentials associated with the appearance of visual perceptual alterations, including visual hallucinations. All of these effects were blocked by pretreatment with the 5-HT2A antagonist ketanserin, indicating that activation of 5-HT2A receptors by psilocybin profoundly modulates the neurophysiological and phenomenological indices of visual processing. Specifically, activation of 5-HT2A receptors may induce a processing mode in which stimulus-driven cortical excitation is overwhelmed by spontaneous neuronal excitation through the modulation of α oscillations. Furthermore, the observed reduction of N170 visual-evoked potentials may be a key mechanism underlying 5-HT2A receptor-mediated visual hallucinations. This change in N170 potentials may be important not only for psilocybin-induced states but also for understanding acute hallucinatory states seen in psychiatric disorders, such as schizophrenia and Parkinson's disease.

Perceptual learning improves visual performance in juvenile amblyopia.

Science.gov (United States)

Li, Roger W; Young, Karen G; Hoenig, Pia; Levi, Dennis M

2005-09-01

To determine whether practicing a position-discrimination task improves visual performance in children with amblyopia and to determine the mechanism(s) of improvement. Five children (age range, 7-10 years) with amblyopia practiced a positional acuity task in which they had to judge which of three pairs of lines was misaligned. Positional noise was produced by distributing the individual patches of each line segment according to a Gaussian probability function. Observers were trained at three noise levels (including 0), with each observer performing between 3000 and 4000 responses in 7 to 10 sessions. Trial-by-trial feedback was provided. Four of the five observers showed significant improvement in positional acuity. In those four observers, on average, positional acuity with no noise improved by approximately 32% and with high noise by approximately 26%. A position-averaging model was used to parse the improvement into an increase in efficiency or a decrease in equivalent input noise. Two observers showed increased efficiency (51% and 117% improvements) with no significant change in equivalent input noise across sessions. The other two observers showed both a decrease in equivalent input noise (18% and 29%) and an increase in efficiency (17% and 71%). All five observers showed substantial improvement in Snellen acuity (approximately 26%) after practice. Perceptual learning can improve visual performance in amblyopic children. The improvement can be parsed into two important factors: decreased equivalent input noise and increased efficiency. Perceptual learning techniques may add an effective new method to the armamentarium of amblyopia treatments.

Does monocular visual space contain planes?

NARCIS (Netherlands)

Koenderink, J.J.; Albertazzi, L.; Doorn, A.J. van; Ee, R. van; Grind, W.A. van de; Kappers, A.M.L.; Lappin, J.S.; Norman, J.F.; Oomes, A.H.J.; Pas, S.F. te; Phillips, F.; Pont, S.C.; Richards, W.A.; Todd, J.T.; Verstraten, F.A.J.; Vries, S.C. de

2010-01-01

The issue of the existence of planes—understood as the carriers of a nexus of straight lines—in the monocular visual space of a stationary human observer has never been addressed. The most recent empirical data apply to binocular visual space and date from the 1960s (Foley, 1964). This appears to be

Does monocular visual space contain planes?

NARCIS (Netherlands)

Koenderink, Jan J.; Albertazzi, Liliana; van Doorn, Andrea J.; van Ee, Raymond; van de Grind, Wim A.; Kappers, Astrid M L; Lappin, Joe S.; Farley Norman, J.; (Stijn) Oomes, A. H J; te Pas, Susan P.; Phillips, Flip; Pont, Sylvia C.; Richards, Whitman A.; Todd, James T.; Verstraten, Frans A J; de Vries, Sjoerd

The issue of the existence of planes-understood as the carriers of a nexus of straight lines-in the monocular visual space of a stationary human observer has never been addressed. The most recent empirical data apply to binocular visual space and date from the 1960s (Foley, 1964). This appears to be

Software applications to three-dimensional visualization of forest landscapes -- A case study demontrating the use of visual nature studio (VNS) in visualizing fire spread in forest landscapes

Science.gov (United States)

Brian J. Williams; Bo Song; Chou Chiao-Ying; Thomas M. Williams; John Hom

2010-01-01

Three-dimensional (3D) visualization is a useful tool that depicts virtual forest landscapes on computer. Previous studies in visualization have required high end computer hardware and specialized technical skills. A virtual forest landscape can be used to show different effects of disturbances and management scenarios on a computer, which allows observation of forest...

Association between visual impairment and patient-reported visual disability at different stages of cataract surgery.

Science.gov (United States)

Acosta-Rojas, E Ruthy; Comas, Mercè; Sala, Maria; Castells, Xavier

2006-10-01

To evaluate the association between visual impairment (visual acuity, contrast sensitivity, stereopsis) and patient-reported visual disability at different stages of cataract surgery. A cohort of 104 patients aged 60 years and over with bilateral cataract was assessed preoperatively, after first-eye surgery (monocular pseudophakia) and after second-eye surgery (binocular pseudophakia). Partial correlation coefficients (PCC) and linear regression models were calculated. In patients with bilateral cataracts, visual disability was associated with visual acuity (PCC = -0.30) and, to a lesser extent, with contrast sensitivity (PCC = 0.16) and stereopsis (PCC = -0.09). In monocular and binocular pseudophakia, visual disability was more strongly associated with stereopsis (PCC = -0.26 monocular and -0.51 binocular) and contrast sensitivity (PCC = 0.18 monocular and 0.34 binocular) than with visual acuity (PCC = -0.18 monocular and -0.18 binocular). Visual acuity, contrast sensitivity and stereopsis accounted for between 17% and 42% of variance in visual disability. The association of visual impairment with patient-reported visual disability differed at each stage of cataract surgery. Measuring other forms of visual impairment independently from visual acuity, such as contrast sensitivity or stereopsis, could be important in evaluating both needs and outcomes in cataract surgery. More comprehensive assessment of the impact of cataract on patients should include measurement of both visual impairment and visual disability.

Supplementary Material for: A Geometric Approach to Visualization of Variability in Functional Data

KAUST Repository

Xie, Weiyi; Kurtek, Sebastian; Bharath, Karthik; Sun, Ying

2016-01-01

We propose a new method for the construction and visualization of boxplot-type displays for functional data. We use a recent functional data analysis framework, based on a representation of functions called square-root slope functions, to decompose observed variation in functional data into three main components: amplitude, phase, and vertical translation. We then construct separate displays for each component, using the geometry and metric of each representation space, based on a novel definition of the median, the two quartiles, and extreme observations. The outlyingness of functional data is a very complex concept. Thus, we propose to identify outliers based on any of the three main components after decomposition. We provide a variety of visualization tools for the proposed boxplot-type displays including surface plots. We evaluate the proposed method using extensive simulations and then focus our attention on three real data applications including exploratory data analysis of sea surface temperature functions, electrocardiogram functions and growth curves.

Comparison of shade matching by visual observation and an intraoral dental colorimeter.

Science.gov (United States)

Li, Q; Wang, Y N

2007-11-01

The purpose of this study was to compare the applicability of two shade-matching approaches: Vintage Halo shade guide (visual method) and Shofu ShadeEye NCC colorimeter (instrumental method). Twenty participants' maxillary left central incisors were evaluated. Corresponding metal ceramic crowns were fabricated with each shade-matching approach. The colour distributions (L*, a* and b*) of the middle third region of each tooth and corresponding metal ceramic crowns were spectrophotometrically assessed. The colour difference (DeltaE) and colour distributions (DeltaL*, Deltaa* and Deltab*) between the tooth and the corresponding crowns were calculated. We found that the colour differences of both groups fell within the clinical unacceptable range (DeltaE > 2.75). Regarding DeltaE and the three colour distributions, no significant difference was found, expect for a* (P colorimeter nor the visual approach. However, the colorimeter can achieve better results within easy matching cases.

Flow visualization IV; Proceedings of the Fourth International Symposium, Ecole Nationale Superieure de Techniques Avancees, Paris, France, Aug. 26-29, 1986

International Nuclear Information System (INIS)

Veret, C.

1987-01-01

Papers are presented on optical techniques, speckle techniques, observation methods, image processing, boundary layers and separated flows, stratified flows and the mixing layer, vortices and wakes, jets, supersonic and hypersonic flows, the velocity field, two-phase flows, heat transfer, and engines. Specific attention is paid to applications including shear layer stability in axisymmetric backstep flows, visualization of the pulsating flow past aortic prostheses, and flow visualization by dye and by optical interferometry. Other topics include photochromic flow visualization in liquid-liquid two-phase flow, shear flow patterns analyzed by video systems, the visualization of longitudinal vortices in stagnation flows, and the development of the Karman vortex due to buoyant force in opposing flow

Visual outcome in Japanese patients with Acanthamoeba keratitis.

Science.gov (United States)

Yamazoe, K; Yamamoto, Y; Shimazaki-Den, S; Shimazaki, J

2012-04-01

To identify prognostic factors affecting visual outcome in Acanthamoeba keratitis (AK) treated with topical chlorhexidine gluconate (CHG). A total of 35 eyes in 34 patients with AK were treated with 0.02% topical CHG. Patients were divided into two groups according to the final visual outcome: Group 1, final visual acuity (VA) of 20/25 or greater (22 eyes); Group 2, less than 20/25 (13 eyes). We compared these groups and evaluated the effectiveness of topical CHG compared with outcomes in previous reports. Ring infiltrate was observed more often in Group 2 (4.5% vs 61.5%, OR 33.6, 95% confidence interval (CI) 3.4-333.9, PAK was significantly longer (24.9 days vs 48.4 days, OR 1.03, 95% CI 1.00-1.06, P = 0.04) and VA at initial examination (log MAR) significantly lower (0.47 vs 1.59, OR 25.5, 95% CI 3.4-186.7, PAK. Topical CHG was comparably effective to other treatments, including polyhexamethyl biguanide and propamidine isethionate.

Vizic: A Jupyter-based interactive visualization tool for astronomical catalogs

Science.gov (United States)

Yu, W.; Carrasco Kind, M.; Brunner, R. J.

2017-07-01

The ever-growing datasets in observational astronomy have challenged scientists in many aspects, including an efficient and interactive data exploration and visualization. Many tools have been developed to confront this challenge. However, they usually focus on displaying the actual images or focus on visualizing patterns within catalogs in a predefined way. In this paper we introduce Vizic, a Python visualization library that builds the connection between images and catalogs through an interactive map of the sky region. Vizic visualizes catalog data over a custom background canvas using the shape, size and orientation of each object in the catalog. The displayed objects in the map are highly interactive and customizable comparing to those in the observation images. These objects can be filtered by or colored by their property values, such as redshift and magnitude. They also can be sub-selected using a lasso-like tool for further analysis using standard Python functions and everything is done from inside a Jupyter notebook. Furthermore, Vizic allows custom overlays to be appended dynamically on top of the sky map. We have initially implemented several overlays, namely, Voronoi, Delaunay, Minimum Spanning Tree and HEALPix grid layer, which are helpful for visualizing large-scale structure. All these overlays can be generated, added or removed interactively with just one line of code. The catalog data is stored in a non-relational database, and the interfaces have been developed in JavaScript and Python to work within Jupyter Notebook, which allows to create customizable widgets, user generated scripts to analyze and plot the data selected/displayed in the interactive map. This unique design makes Vizic a very powerful and flexible interactive analysis tool. Vizic can be adopted in variety of exercises, for example, data inspection, clustering analysis, galaxy alignment studies, outlier identification or just large scale visualizations.

Joint engagement in infants and its relationship to their visual impairment measurements.

Science.gov (United States)

Urqueta Alfaro, Andrea; Morash, Valerie S; Lei, Daisy; Orel-Bixler, Deborah

2018-02-01

Coordination of attention between a social partner and an external focus of shared interest, called joint engagement, is associated with positive developmental outcomes such as better language, socio-emotional, and theory of mind skills in sighted infants. Current measures of joint engagement rely on an infant's visual behaviors, making it difficult to study joint engagement in infants with low or no vision. In a naturalistic observational study, 20 infants with various levels of visual impairments - mean ages: 1.08 years (N=9) and 1.62 years (N=18), were videotaped during 30-min free play sessions with their caregivers. Seven infants were tested at both ages. Videos were coded to determine the percentage of time the dyads participated in joint engagement. Results showed that all visually impaired infants participated in joint engagement, with a significant increase between earlier and later ages. Infants' visual impairment levels were described in terms of visual acuity and contrast sensitivity as measured using both visual evoked potential and preferential looking techniques. Of the visual measurements, infants' reduction in contrast sensitivity measured with preferential looking, alone, predicted the infants' percentage of time in joint engagement across ages. Contrary to prior research that exclusively focused on visual acuity, this finding supports the need to include contrast sensitivity measurements in studies with visually impaired infants. Copyright © 2017 Elsevier Inc. All rights reserved.

Data Cube Visualization with Blender

Science.gov (United States)

Kent, Brian R.; Gárate, Matías

2017-06-01

With the increasing data acquisition rates from observational and computational astrophysics, new tools are needed to study and visualize data. We present a methodology for rendering 3D data cubes using the open-source 3D software Blender. By importing processed observations and numerical simulations through the Voxel Data format, we are able use the Blender interface and Python API to create high-resolution animated visualizations. We review the methods for data import, animation, and camera movement, and present examples of this methodology. The 3D rendering of data cubes gives scientists the ability to create appealing displays that can be used for both scientific presentations as well as public outreach.

Visual Complaints and Eye Problems in Orchestral Musicians.

Science.gov (United States)

Beckers, Henny Jm; van Kooten-Noordzij, Marina Aw; de Crom, Ronald Mpc; Schouten, Jan Sag; Webers, Carroll Ab

2016-09-01

To study visual complaints and eye diseases among professional and amateur orchestral musicians in the Netherlands. In this observational study, members from professional and amateur symphony or wind orchestras were asked to complete a questionnaire collecting demographic data, musical, medical, and family history, and data on present visual complaints and/or eye diseases. Questions about playing in the orchestra were also asked. Data from 70 professionals and 48 amateurs showed that most musicians needed glasses or contact lenses for playing in the orchestra (61% of the professionals, 63% of the amateurs). A majority (66% of professionals, 71% of amateurs) had visited an ophthalmologist at least once during their lifetime, and 10% of the professionals and 23% of the amateurs were currently under treatment of an ophthalmologist. Visual complaints while playing in the orchestra were quite common and included poor lighting conditions, problems with reading small notes, blurred vision, tired eyes, and itching or burning eyes. Professional musicians especially reported adverse effects of eye complaints encountered in the orchestra for daily life; 35% got tired earlier and 33% felt that they could not adequately perform their tasks in the orchestra. The results show that visual complaints and eye problems probably are quite common among orchestral musicians and therefore warrant further interest and research.

Reflective Reconstruction of Visual Products

DEFF Research Database (Denmark)

Otrel-Cass, Kathrin

2017-01-01

objects. The teacher used a range of visual materials including video clips, diagrams, student drawings, and student produced 3D models, each endowed with unique material and visual dimensions. The teacher activated those through talking, writing, drawing and working with artifacts and purposefully...

Advancements to Visualization Control System (VCS, part of UV-CDAT), a Visualization Package Designed for Climate Scientists

Science.gov (United States)

Lipsa, D.; Chaudhary, A.; Williams, D. N.; Doutriaux, C.; Jhaveri, S.

2017-12-01

Climate Data Analysis Tools (UV-CDAT, https://uvcdat.llnl.gov) is a data analysis and visualization software package developed at Lawrence Livermore National Laboratory and designed for climate scientists. Core components of UV-CDAT include: 1) Community Data Management System (CDMS) which provides I/O support and a data model for climate data;2) CDAT Utilities (GenUtil) that processes data using spatial and temporal averaging and statistic functions; and 3) Visualization Control System (VCS) for interactive visualization of the data. VCS is a Python visualization package primarily built for climate scientists, however, because of its generality and breadth of functionality, it can be a useful tool to other scientific applications. VCS provides 1D, 2D and 3D visualization functions such as scatter plot and line graphs for 1d data, boxfill, meshfill, isofill, isoline for 2d scalar data, vector glyphs and streamlines for 2d vector data and 3d_scalar and 3d_vector for 3d data. Specifically for climate data our plotting routines include projections, Skew-T plots and Taylor diagrams. While VCS provided a user-friendly API, the previous implementation of VCS relied on slow performing vector graphics (Cairo) backend which is suitable for smaller dataset and non-interactive graphics. LLNL and Kitware team has added a new backend to VCS that uses the Visualization Toolkit (VTK) as its visualization backend. VTK is one of the most popular open source, multi-platform scientific visualization library written in C++. Its use of OpenGL and pipeline processing architecture results in a high performant VCS library. Its multitude of available data formats and visualization algorithms results in easy adoption of new visualization methods and new data formats in VCS. In this presentation, we describe recent contributions to VCS that includes new visualization plots, continuous integration testing using Conda and CircleCI, tutorials and examples using Jupyter notebooks as well as

Visual cues for data mining

Science.gov (United States)

Rogowitz, Bernice E.; Rabenhorst, David A.; Gerth, John A.; Kalin, Edward B.

1996-04-01

This paper describes a set of visual techniques, based on principles of human perception and cognition, which can help users analyze and develop intuitions about tabular data. Collections of tabular data are widely available, including, for example, multivariate time series data, customer satisfaction data, stock market performance data, multivariate profiles of companies and individuals, and scientific measurements. In our approach, we show how visual cues can help users perform a number of data mining tasks, including identifying correlations and interaction effects, finding clusters and understanding the semantics of cluster membership, identifying anomalies and outliers, and discovering multivariate relationships among variables. These cues are derived from psychological studies on perceptual organization, visual search, perceptual scaling, and color perception. These visual techniques are presented as a complement to the statistical and algorithmic methods more commonly associated with these tasks, and provide an interactive interface for the human analyst.

Visual training paired with electrical stimulation of the basal forebrain improves orientation-selective visual acuity in the rat.

Science.gov (United States)

Kang, Jun Il; Groleau, Marianne; Dotigny, Florence; Giguère, Hugo; Vaucher, Elvire

2014-07-01

The cholinergic afferents from the basal forebrain to the primary visual cortex play a key role in visual attention and cortical plasticity. These afferent fibers modulate acute and long-term responses of visual neurons to specific stimuli. The present study evaluates whether this cholinergic modulation of visual neurons results in cortical activity and visual perception changes. Awake adult rats were exposed repeatedly for 2 weeks to an orientation-specific grating with or without coupling this visual stimulation to an electrical stimulation of the basal forebrain. The visual acuity, as measured using a visual water maze before and after the exposure to the orientation-specific grating, was increased in the group of trained rats with simultaneous basal forebrain/visual stimulation. The increase in visual acuity was not observed when visual training or basal forebrain stimulation was performed separately or when cholinergic fibers were selectively lesioned prior to the visual stimulation. The visual evoked potentials show a long-lasting increase in cortical reactivity of the primary visual cortex after coupled visual/cholinergic stimulation, as well as c-Fos immunoreactivity of both pyramidal and GABAergic interneuron. These findings demonstrate that when coupled with visual training, the cholinergic system improves visual performance for the trained orientation probably through enhancement of attentional processes and cortical plasticity in V1 related to the ratio of excitatory/inhibitory inputs. This study opens the possibility of establishing efficient rehabilitation strategies for facilitating visual capacity.

Visual loss at presentation in children with pseudotumor cerebri

Directory of Open Access Journals (Sweden)

Rana Al-Senawi

2008-01-01

Full Text Available Purpose: To describe visual loss at presentation in children with pseudotumor cerebri (PTC, and discuss mechanisms of visual loss and distinguishing features of pediatric PTC. Materials and Methods: Two children with papilledema and visual complaints were referred for ophthalmic evaluation. Both patients underwent a detailed ophthalmic work-up. Results: Patient 1, an 8-year-old girl, presented with a 2-week history of headache, vomiting, and visual impairment in both eyes. The child had no previous medical history. Patient 2, a 9-year-old boy, experienced sudden loss of vision in both eyes one week prior to presentation, along with severe headache and vomiting. He had undergone a renal transplantation one year back, and his current medications included cyclosporine A (CsA and oral prednisolone. Extensive disc swelling, lipid exudation and retinal thickening in the posterior pole were observed in both patients. Lumbar puncture in both showed elevated cerebrospinal fluid pressure. Both were treated with oral acetazolamide. Patient 1 additionally received intravenous methylprednisolone followed by an oral taper. CsA was stopped in patient 2. PTC and papilledema resolved with above measures in both patients, with partial recovery of visual function. Conclusions: PTC in children may have atypical manifestations. Visual acuity may be compromised acutely due to several factors. Patients with PTC and severe visual loss at presentation mandate an aggressive management approach. Use of intravenous steroids may be considered along with acetazolamide. Despite resolution of PTC, sequelae such as optic atrophy or macular scarring may impede eventual visual recovery. Physicians following patients on CsA need to be aware of the possible neuro-ophthalmic complications of the drug.

Visual evaluation of beef tenderness by using surface structural ...

African Journals Online (AJOL)

Very low negative correlations were observed between colour and shear force (r = −0.242). Therefore, although it may be possible to judge meat colour by visual analysis, it does not appear possible to predict tenderness by colour judgment. There is potential for an experienced eye to predict tenderness by observing visual ...

Phenotypes in defined genotypes including siblings with Usher syndrome.

Science.gov (United States)

Malm, Eva; Ponjavic, Vesna; Möller, Claes; Kimberling, William J; Andréasson, Sten

2011-06-01

To characterize visual function in defined genotypes including siblings with Usher syndrome. Thirteen patients with phenotypically different subtypes of Usher syndrome, including 3 families with affected siblings, were selected. Genetic analysis and ophthalmological examinations including visual fields, full-field electroretinography (ERG), multifocal electroretinography (mf ERG), and optical coherence tomography (OCT) were assessed. The patients' degree of visual handicap was evaluated by a questionnaire (ADL). Twelve of thirteen patients were genotyped as Usher 1B, 1D, 1F, 2A, 2C or 3A. In 12 of 13 patients examined with ERG the 30 Hz flickering light response revealed remaining cone function. In 3 of the patients with Usher type 1 mf ERG demonstrated a specific pattern, with a sharp distinction between the area with reduced function and the central area with remaining macular function and normal peak time. OCT demonstrated loss of foveal depression with distortion of the foveal architecture in the macula in all patients. The foveal thickness ranged from 159 to 384 µm and was not correlated to retinal function. Three siblings shared the same mutation for Usher 2C but in contrast to previous reports regarding this genotype, 1 of them diverged in phenotype with substantially normal visual fields, almost normal OCT and mf ERG findings, and only moderately reduced rod and cone function according to ERG. Evaluation of visual function comprising both the severity of the rod cone degeneration and the function in the macular region confirm phenotypical heterogeneity within siblings and between different genotypes of Usher syndrome.

Math for visualization, visualizing math

NARCIS (Netherlands)

Wijk, van J.J.; Hart, G.; Sarhangi, R.

2013-01-01

I present an overview of our work in visualization, and reflect on the role of mathematics therein. First, mathematics can be used as a tool to produce visualizations, which is illustrated with examples from information visualization, flow visualization, and cartography. Second, mathematics itself

Neural mechanisms underlying sound-induced visual motion perception: An fMRI study.

Science.gov (United States)

Hidaka, Souta; Higuchi, Satomi; Teramoto, Wataru; Sugita, Yoichi

2017-07-01

Studies of crossmodal interactions in motion perception have reported activation in several brain areas, including those related to motion processing and/or sensory association, in response to multimodal (e.g., visual and auditory) stimuli that were both in motion. Recent studies have demonstrated that sounds can trigger illusory visual apparent motion to static visual stimuli (sound-induced visual motion: SIVM): A visual stimulus blinking at a fixed location is perceived to be moving laterally when an alternating left-right sound is also present. Here, we investigated brain activity related to the perception of SIVM using a 7T functional magnetic resonance imaging technique. Specifically, we focused on the patterns of neural activities in SIVM and visually induced visual apparent motion (VIVM). We observed shared activations in the middle occipital area (V5/hMT), which is thought to be involved in visual motion processing, for SIVM and VIVM. Moreover, as compared to VIVM, SIVM resulted in greater activation in the superior temporal area and dominant functional connectivity between the V5/hMT area and the areas related to auditory and crossmodal motion processing. These findings indicate that similar but partially different neural mechanisms could be involved in auditory-induced and visually-induced motion perception, and neural signals in auditory, visual, and, crossmodal motion processing areas closely and directly interact in the perception of SIVM. Copyright © 2017 Elsevier B.V. All rights reserved.

The Ascendancy of the Visual and Issues of Gender: Equality versus Difference.

Science.gov (United States)

Damarin, Suzanne K.

1993-01-01

Discussion of visual literacy, visual cognition, visual thinking and learning, and visual knowledge focuses on women and gender differences. Topics addressed include educational equality and the visual, including equality versus difference; women and mass culture; difference and the design of visual instruction; and feminist education and the…

Uncertainty in Citizen Science observations: from measurement to user perception

Science.gov (United States)

Lahoz, William; Schneider, Philipp; Castell, Nuria

2016-04-01

Citizen Science activities concern general public engagement in scientific research activities when citizens actively contribute to science either with their intellectual effort or surrounding knowledge or with their tools and resources. The advent of technologies such as the Internet and smartphones, and the growth in their usage, has significantly increased the potential benefits from Citizen Science activities. Citizen Science observations from low-cost sensors, smartphones and Citizen Observatories, provide a novel and recent development in platforms for observing the Earth System, with the opportunity to extend the range of observational platforms available to society to spatio-temporal scales (10-100s m; 1 hr or less) highly relevant to citizen needs. The potential value of Citizen Science is high, with applications in science, education, social aspects, and policy aspects, but this potential, particularly for citizens and policymakers, remains largely untapped. Key areas where Citizen Science data start to have demonstrable benefits include GEOSS Societal Benefit Areas such as Health and Weather. Citizen Science observations have many challenges, including simulation of smaller spatial scales, noisy data, combination with traditional observational methods (satellite and in situ data), and assessment, representation and visualization of uncertainty. Within these challenges, that of the assessment and representation of uncertainty and its communication to users is fundamental, as it provides qualitative and/or quantitative information that influences the belief users will have in environmental information. This presentation will discuss the challenges in assessment and representation of uncertainty in Citizen Science observations, its communication to users, including the use of visualization, and the perception of this uncertainty information by users of Citizen Science observations.

Stable statistical representations facilitate visual search.

Science.gov (United States)

Corbett, Jennifer E; Melcher, David

2014-10-01

Observers represent the average properties of object ensembles even when they cannot identify individual elements. To investigate the functional role of ensemble statistics, we examined how modulating statistical stability affects visual search. We varied the mean and/or individual sizes of an array of Gabor patches while observers searched for a tilted target. In "stable" blocks, the mean and/or local sizes of the Gabors were constant over successive displays, whereas in "unstable" baseline blocks they changed from trial to trial. Although there was no relationship between the context and the spatial location of the target, observers found targets faster (as indexed by faster correct responses and fewer saccades) as the global mean size became stable over several displays. Building statistical stability also facilitated scanning the scene, as measured by larger saccadic amplitudes, faster saccadic reaction times, and shorter fixation durations. These findings suggest a central role for peripheral visual information, creating context to free resources for detailed processing of salient targets and maintaining the illusion of visual stability.

Visual Magnocellular Function in Perceptual Disorders

Directory of Open Access Journals (Sweden)

David P. Crewther

2011-05-01

Full Text Available Developmental disorders such as autism spectrum disorders (ASD, dyslexia, schizophrenia and dyscalculia have also been reported to show abnormal visual perception. Central to the four disorders are observations of altered global/local perception, motion sensation and grouping that are suggestive of a magnocellular abnormality(s. Such psychophysical observations do not easily yield neurophysiological mechanisms that can explain the altered perception/vision. Nonlinear visual evoked potentials have allowed the separation of magnocellular (M and parvocellular (P contributions to the VEP (Klistorner et al., 1997. Using these tools we compare the patterns of abnormality in groups with visual disorders. The second order kernel responses of the VEP in autistic tendency show interference between P and M nonlinearities at high contrast (Sutherland & Crewther, 2010 resulting in a delay of completion of firing. While afferent latencies of M and P cortical activation are not different in ASD, the delay in completion may allow a revision of the ideas surrounding the “magnocellular advantage” which relate to the alterations observed in global and local perception.

A visual tristimulus projection colorimeter.

Science.gov (United States)

Valberg, A

1971-01-01

Based on the optical principle of a slide projector, a visual tristimulus projection colorimeter has been developed. The calorimeter operates with easily interchangeable sets of primary color filters placed in a frame at the objective. The apparatus has proved to be fairly accurate. The reproduction of the color matches as measured by the standard deviation is equal to the visual sensitivity to color differences for each observer. Examples of deviations in the matches among individuals as well as deviations compared with the CIE 1931 Standard Observer are given. These deviations are demonstrated to be solely due to individual differences in the perception of metameric colors. Thus, taking advantage of an objective observation (allowing all adjustments to be judged by a group of impartial observers), the colorimeter provides an excellent aid in the study of discrimination, metamerism, and related effects which are of considerable interest in current research in colorimetry and in the study of color vision tests.

Optical radiation and visual health

International Nuclear Information System (INIS)

Waxler, M.; Hitchins, V.M.

1986-01-01

This book provides a focus on the parameters of ultraviolet light, visible, and infrared radiation s which could cause long-term visual health problems in humans. It reviews early research on radiation effects on the eye, and gives detailed attention to the hazardous effects of optical radiation on the retinal pigment epithelium and the photoreceptors. These data are further analyzed with regard to five potential long-term visual health problems; retinal degeneration, visual aging, disorder of visual development, ocular drug phototoxicity, and cataracts. Finally, epidemiologic principles for studying the relationships between optical radiation and long-term visual health problems are reviewed, concluding with the implications for future research and radiation protection. The contents include: historical perspectives; optical radiation and cataracts; the involvement of the retinal pigment epithelium (RPE); optical radiation damage to the ocular photoreceptors; possible role of optical radiation in retinal degenerations; optical radiation and the aged eye; optical radiation effects on aging and visual perception; optical radiation effects on visual development; and index

Structural reorganization of the early visual cortex following Braille training in sighted adults.

Science.gov (United States)

Bola, Łukasz; Siuda-Krzywicka, Katarzyna; Paplińska, Małgorzata; Sumera, Ewa; Zimmermann, Maria; Jednoróg, Katarzyna; Marchewka, Artur; Szwed, Marcin

2017-12-12

Training can induce cross-modal plasticity in the human cortex. A well-known example of this phenomenon is the recruitment of visual areas for tactile and auditory processing. It remains unclear to what extent such plasticity is associated with changes in anatomy. Here we enrolled 29 sighted adults into a nine-month tactile Braille-reading training, and used voxel-based morphometry and diffusion tensor imaging to describe the resulting anatomical changes. In addition, we collected resting-state fMRI data to relate these changes to functional connectivity between visual and somatosensory-motor cortices. Following Braille-training, we observed substantial grey and white matter reorganization in the anterior part of early visual cortex (peripheral visual field). Moreover, relative to its posterior, foveal part, the peripheral representation of early visual cortex had stronger functional connections to somatosensory and motor cortices even before the onset of training. Previous studies show that the early visual cortex can be functionally recruited for tactile discrimination, including recognition of Braille characters. Our results demonstrate that reorganization in this region induced by tactile training can also be anatomical. This change most likely reflects a strengthening of existing connectivity between the peripheral visual cortex and somatosensory cortices, which suggests a putative mechanism for cross-modal recruitment of visual areas.

A Bilateral Advantage for Storage in Visual Working Memory

Science.gov (United States)

Umemoto, Akina; Drew, Trafton; Ester, Edward F.; Awh, Edward

2010-01-01

Various studies have demonstrated enhanced visual processing when information is presented across both visual hemifields rather than in a single hemifield (the "bilateral advantage"). For example, Alvarez and Cavanagh (2005) reported that observers were able to track twice as many moving visual stimuli when the tracked items were presented…

Visualizing Data from EarthScope's USArray

Science.gov (United States)

Woodward, R.; Frassetto, A.; Adinolfi, A.

2012-12-01

The EarthScope USArray program has generated a large volume of data from across the North American continent. The Transportable Array (TA) component of USArray has deployed over 400 seismic stations in a grid with 70 km spacing between stations. The TA has rolled the array across the contiguous US states over a ten-year period, and will have occupied over 1600 distinct sites from the Pacific Ocean to the Atlantic Ocean by the end of 2013. All stations transmit multiple channels of 40 samples per second data continuously, in near real time. Each station records and transmits seismic, barometric pressure, and infrasound data, as well as various state-of-health data streams. All data are immediately open and unrestricted. The TA provides a unique tool for visualizing large-scale seismic wave phenomena. The power of this tool is particularly apparent when displaying simultaneous signals from all stations as a function of time, as well as rendering multiple channels of data from each station. In this situation it is challenging to convey the 3D motion at each station as well as the aggregate 3D motion across the entire set of 400 stations. Creating movies of the data becomes essential to illustrate the time dependence of the observations. Typically the rendering of such movies requires the use of programming language that is suitable for both data analysis and graphics, as it is essential to explore different data pre-processing strategies (often filtering, but also including other pre-processing steps). Different visualization strategies provide a means for dealing with the very large volume of data generated by the TA. Typical data review strategies include a survey mode to scan large volumes of data for signals of interest, or zooming in on fine features using combinations of specialized data processing and frame-by-frame time-steps, or going back and forth between the two modes. The data visualizations are continuously evolving to explore new ideas. The movie

Visualizing the Past: The Design of a Temporally Enabled Map for Presentation (TEMPO

Directory of Open Access Journals (Sweden)

Nathan Prestopnik

2012-01-01

Full Text Available We present a design case for a prototype visualization tool called the Temporally Enabled Map for Presentation (TEMPO. Designed for use in the lecture classroom, TEMPO is an interactive animated map that addressed a common problem in military history: the shortcomings of traditional static (non-interactive, non-animated maps. Static maps show spatial elements well, but cannot do more than approximate temporal events using multiple views, movement arrows, and the like. TEMPO provides a more complete view of past historical events by showing them from start to finish. In our design case we describe our development process, which included consultation with military history domain experts, classroom observations, application of techniques derived from visualization and Human-Computer Interaction (HCI literature and theory. Our design case shows how the design of an educational tool can motivate scholarly evaluation, and we describe how some theories were first embraced and then rejected as design circumstances required. Finally, we explore a future direction for TEMPO, tools to support creative interactions with visualizations where students or instructors can learn by visualizing historical events for themselves. A working version of the finished TEMPO artifact is included as an interactive element in this document.

Visual attention capacity after right hemisphere lesions

DEFF Research Database (Denmark)

Habekost, Thomas; Rostrup, Egill

2007-01-01

Recently there has been a growing interest in visual short-term memory (VSTM) including the neural basis of the function. Processing speed, another main aspect of visual attention capacity, has received less investigation. For both cognitive functions human lesion studies are sparse. We used...... a whole report experiment for estimation of these two parameters in 22 patients with right side stroke. Psychophysical performance was analyzed using Bundesen's [Bundesen, C. (1990). A theory of visual attention. Psychological Review, 97, 523-547] Theory of Visual Attention (TVA) and compared...... for both VSTM capacity and ipsilesional processing speed. The study also showed that lesions in a large region of the right hemisphere, including the putamen, insula, and inferior frontal cortex, do not lead to general deficits in the capacity of visual attention. Udgivelsesdato: 2007-Apr-8...

Ivor Horton's beginning visual C++ 2013

CERN Document Server

Horton, Ivor

2014-01-01

Learn C++ with the best tutorial on the market! Horton's unique tutorial approach and step-by-step guidance have helped over 100,000 novice programmers learn C++. In Ivor Horton's Beginning Visual C++ 2013, Horton not only guides you through the fundamentals of the standard C++ language, but also teaches you how C++ is used in the latest Visual Studio 2013 environment. Visual Studio 2013 includes major changes to the IDE and expanded options for C++ coding. Ivor Horton's Beginning Visual C++ 2013 will teach you the latest techniques to take your Visual C++ coding to an all-new level.C++ langua

Brain correlates of automatic visual change detection.

Science.gov (United States)

Cléry, H; Andersson, F; Fonlupt, P; Gomot, M

2013-07-15

A number of studies support the presence of visual automatic detection of change, but little is known about the brain generators involved in such processing and about the modulation of brain activity according to the salience of the stimulus. The study presented here was designed to locate the brain activity elicited by unattended visual deviant and novel stimuli using fMRI. Seventeen adult participants were presented with a passive visual oddball sequence while performing a concurrent visual task. Variations in BOLD signal were observed in the modality-specific sensory cortex, but also in non-specific areas involved in preattentional processing of changing events. A degree-of-deviance effect was observed, since novel stimuli elicited more activity in the sensory occipital regions and at the medial frontal site than small changes. These findings could be compared to those obtained in the auditory modality and might suggest a "general" change detection process operating in several sensory modalities. Copyright © 2013 Elsevier Inc. All rights reserved.

Diagnosing cerebral visual impairment in children with good visual acuity.

Science.gov (United States)

van Genderen, Maria; Dekker, Marjoke; Pilon, Florine; Bals, Irmgard

2012-06-01

To identify elements that could facilitate the diagnosis of cerebral visual impairment (CVI) in children with good visual acuity in the general ophthalmic clinic. We retrospectively investigated the clinical characteristics of 30 children with good visual acuity and CVI and compared them with those of 23 children who were referred with a suspicion of CVI, but proved to have a different diagnosis. Clinical characteristics included medical history, MRI findings, visual acuity, crowding ratio (CR), visual field assessment, and the results of ophthalmologic and orthoptic examination. We also evaluated the additional value of a short CVI questionnaire. Eighty-three percent of the children with an abnormal medical history (mainly prematurity and perinatal hypoxia) had CVI, in contrast with none of the children with a normal medical history. Cerebral palsy, visual field defects, and partial optic atrophy only occurred in the CVI group. 41% of the children with CVI had a CR ≥2.0, which may be related to dorsal stream dysfunction. All children with CVI, but also 91% of the children without CVI gave ≥3 affirmative answers on the CVI questionnaire. An abnormal pre- or perinatal medical history is the most important risk factor for CVI in children, and therefore in deciding which children should be referred for further multidisciplinary assessment. Additional symptoms of cerebral damage, i.e., cerebral palsy, visual field defects, partial optic atrophy, and a CR ≥2 may support the diagnosis. CVI questionnaires should not be used for screening purposes as they yield too many false positives.

Non-retinotopic motor-visual recalibration to temporal lag

Directory of Open Access Journals (Sweden)

Masaki eTsujita

2012-11-01

Full Text Available Temporal order judgment between the voluntary motor action and its perceptual feedback is important in distinguishing between a sensory feedback which is caused by observer’s own action and other stimulus, which are irrelevant to that action. Prolonged exposure to fixed temporal lag between motor action and visual feedback recalibrates motor-visual temporal relationship, and consequently shifts the point of subjective simultaneity (PSS. Previous studies on the audio-visual temporal recalibration without voluntary action revealed that both low and high level processing are involved. However, it is not clear how the low and high level processings affect the recalibration to constant temporal lag between voluntary action and visual feedback. This study examined retinotopic specificity of the motor-visual temporal recalibration. During the adaptation phase, observers repeatedly pressed a key, and visual stimulus was presented in left or right visual field with a fixed temporal lag (0 or 200 ms. In the test phase, observers performed a temporal order judgment for observer’s voluntary keypress and test stimulus, which was presented in the same as or opposite to the visual field in which the stimulus was presented in the adaptation phase. We found that the PSS was shifted toward the exposed lag in both visual fields. These results suggest that the low visual processing, which is retinotopically specific, has minor contribution to the multimodal adaptation, and that the adaptation to shift the PSS mainly depends upon the high level processing such as attention to specific properties of the stimulus.

Student preparation and the power of visual input in veterinary surgical education

DEFF Research Database (Denmark)

Langebæk, Rikke; Nielsen, Søren Saxmose; Koch, Bodil Cathrine

2016-01-01

In recent years, veterinary educational institutions have implemented alternative teaching methods, including video demonstrations of surgical procedures. However, the power of the dynamic visual input from videos in relation to recollection of a surgical procedure has never been evaluated. The aim...... a basic surgical skills course, 112 fourth-year veterinary students participated in the study by completing a questionnaire regarding method of recollection, influence of individual types of educational input, and homework preparation. Furthermore, we observed students performing an orchiectomy...... in a terminal pig lab. Preparation for the pig lab consisted of homework (textbook, online material, including videos), lecture, cadaver lab, and toy animal models in a skills lab. In the instructional video, a detail was used that was not described elsewhere. Results show that 60% of the students used a visual...

Human Vision and the Night Sky Hot to Improve Your Observing Skills

CERN Document Server

Borgia, Michael P

2006-01-01

This book is not for beginners. Nor is it for experts – instead it addresses the needs of practical amateur astronomers who want to make the jump to the new challenges of serious visual observing. Second Steps in Observational Astronomy begins by teaching you, as an amateur astronomer, to use the most important tool you have: your eyes. Visual observing is very definitely a skill that can be learned. Of course it is important to have your other optical equipment – telescope and accessories – set up and operating as perfectly as possible. This book describes how. After these vital preliminaries, subsequent chapters include a series of observing challenges that will entertain you and push your observing skills to continually higher levels of excellence for years to come. Take a tour of the solar-system as you never viewed it before, then beyond into the realm of deep space – using just your own eyes to reveal more detail than you ever thought possible.

Evidence for unlimited capacity processing of simple features in visual cortex.

Science.gov (United States)

White, Alex L; Runeson, Erik; Palmer, John; Ernst, Zachary R; Boynton, Geoffrey M

2017-06-01

Performance in many visual tasks is impaired when observers attempt to divide spatial attention across multiple visual field locations. Correspondingly, neuronal response magnitudes in visual cortex are often reduced during divided compared with focused spatial attention. This suggests that early visual cortex is the site of capacity limits, where finite processing resources must be divided among attended stimuli. However, behavioral research demonstrates that not all visual tasks suffer such capacity limits: The costs of divided attention are minimal when the task and stimulus are simple, such as when searching for a target defined by orientation or contrast. To date, however, every neuroimaging study of divided attention has used more complex tasks and found large reductions in response magnitude. We bridged that gap by using functional magnetic resonance imaging to measure responses in the human visual cortex during simple feature detection. The first experiment used a visual search task: Observers detected a low-contrast Gabor patch within one or four potentially relevant locations. The second experiment used a dual-task design, in which observers made independent judgments of Gabor presence in patches of dynamic noise at two locations. In both experiments, blood-oxygen level-dependent (BOLD) signals in the retinotopic cortex were significantly lower for ignored than attended stimuli. However, when observers divided attention between multiple stimuli, BOLD signals were not reliably reduced and behavioral performance was unimpaired. These results suggest that processing of simple features in early visual cortex has unlimited capacity.

The influence of assistive technology devices on the performance of activities by visually impaired

Directory of Open Access Journals (Sweden)

Suzana Rabello

2014-04-01

Full Text Available Objective: To establish the influence of assistive technology devices (ATDs on the performance of activities by visually impaired schoolchildren in the resource room. Methods: A qualitative study that comprised observation and an educational intervention in the resource room. The study population comprised six visually impaired schoolchildren aged 12 to 14 years old. The participants were subjected to an eye examination, prescribed ATDs comprising optical and non-optical devices, and provided an orientation on the use of computers. The participants were assessed based on eye/object distance, font size, and time to read a computer screen and printed text. Results: The ophthalmological conditions included corneal opacity, retinochoroiditis, retinopathy of prematurity, aniridia, and congenital cataracts. Far visual acuity varied from 20/200 to 20/800 and near visual acuity from 0.8 to 6 M. Telescopes, spherical lenses, and support magnifying glasses were prescribed. Three out of five participants with low vision after intervention could decrease the font size on the screen computer, and most participants (83.3% reduced their reading time at the second observation session. Relative to the printed text, all the participants with low vision were able to read text written in smaller font sizes and reduced their reading time at the second observation session. Conclusion: Reading skills improved after the use of ATDs, which allowed the participants to perform their school tasks equally to their classmates.

Visual art and visual perception

NARCIS (Netherlands)

Koenderink, Jan J.

2015-01-01

Visual art and visual perception ‘Visual art’ has become a minor cul-de-sac orthogonal to THE ART of the museum directors and billionaire collectors. THE ART is conceptual, instead of visual. Among its cherished items are the tins of artist’s shit (Piero Manzoni, 1961, Merda d’Artista) “worth their

Long-Term Visual Prognosis of Peripheral Multifocal Chorioretinitis

NARCIS (Netherlands)

Ossewaarde-van Norel, J; ten Dam-van Loon, NH; de Boer, JH; Rothova, A.

2015-01-01

Purpose To report on the clinical manifestations, complications, and long-term visual prognosis of patients with peripheral multifocal chorioretinitis and to search for predictors for a lower visual outcome. Design Retrospective consecutive observational case series. Methods setting: Institutional.

Peripheral vision of youths with low vision: motion perception, crowding, and visual search.

Science.gov (United States)

Tadin, Duje; Nyquist, Jeffrey B; Lusk, Kelly E; Corn, Anne L; Lappin, Joseph S

2012-08-24

Effects of low vision on peripheral visual function are poorly understood, especially in children whose visual skills are still developing. The aim of this study was to measure both central and peripheral visual functions in youths with typical and low vision. Of specific interest was the extent to which measures of foveal function predict performance of peripheral tasks. We assessed central and peripheral visual functions in youths with typical vision (n = 7, ages 10-17) and low vision (n = 24, ages 9-18). Experimental measures used both static and moving stimuli and included visual crowding, visual search, motion acuity, motion direction discrimination, and multitarget motion comparison. In most tasks, visual function was impaired in youths with low vision. Substantial differences, however, were found both between participant groups and, importantly, across different tasks within participant groups. Foveal visual acuity was a modest predictor of peripheral form vision and motion sensitivity in either the central or peripheral field. Despite exhibiting normal motion discriminations in fovea, motion sensitivity of youths with low vision deteriorated in the periphery. This contrasted with typically sighted participants, who showed improved motion sensitivity with increasing eccentricity. Visual search was greatly impaired in youths with low vision. Our results reveal a complex pattern of visual deficits in peripheral vision and indicate a significant role of attentional mechanisms in observed impairments. These deficits were not adequately captured by measures of foveal function, arguing for the importance of independently assessing peripheral visual function.

Creating visual explanations improves learning.

Science.gov (United States)

Bobek, Eliza; Tversky, Barbara

2016-01-01

Many topics in science are notoriously difficult for students to learn. Mechanisms and processes outside student experience present particular challenges. While instruction typically involves visualizations, students usually explain in words. Because visual explanations can show parts and processes of complex systems directly, creating them should have benefits beyond creating verbal explanations. We compared learning from creating visual or verbal explanations for two STEM domains, a mechanical system (bicycle pump) and a chemical system (bonding). Both kinds of explanations were analyzed for content and learning assess by a post-test. For the mechanical system, creating a visual explanation increased understanding particularly for participants of low spatial ability. For the chemical system, creating both visual and verbal explanations improved learning without new teaching. Creating a visual explanation was superior and benefitted participants of both high and low spatial ability. Visual explanations often included crucial yet invisible features. The greater effectiveness of visual explanations appears attributable to the checks they provide for completeness and coherence as well as to their roles as platforms for inference. The benefits should generalize to other domains like the social sciences, history, and archeology where important information can be visualized. Together, the findings provide support for the use of learner-generated visual explanations as a powerful learning tool.

Effects of visual attention on chromatic and achromatic detection sensitivities.

Science.gov (United States)

Uchikawa, Keiji; Sato, Masayuki; Kuwamura, Keiko

2014-05-01

Visual attention has a significant effect on various visual functions, such as response time, detection and discrimination sensitivity, and color appearance. It has been suggested that visual attention may affect visual functions in the early visual pathways. In this study we examined selective effects of visual attention on sensitivities of the chromatic and achromatic pathways to clarify whether visual attention modifies responses in the early visual system. We used a dual task paradigm in which the observer detected a peripheral test stimulus presented at 4 deg eccentricities while the observer concurrently carried out an attention task in the central visual field. In experiment 1, it was confirmed that peripheral spectral sensitivities were reduced more for short and long wavelengths than for middle wavelengths with the central attention task so that the spectral sensitivity function changed its shape by visual attention. This indicated that visual attention affected the chromatic response more strongly than the achromatic response. In experiment 2 it was obtained that the detection thresholds increased in greater degrees in the red-green and yellow-blue chromatic directions than in the white-black achromatic direction in the dual task condition. In experiment 3 we showed that the peripheral threshold elevations depended on the combination of color-directions of the central and peripheral stimuli. Since the chromatic and achromatic responses were separately processed in the early visual pathways, the present results provided additional evidence that visual attention affects responses in the early visual pathways.

NEW MASER EMISSION FROM NONMETASTABLE AMMONIA IN NGC 7538. II. GREEN BANK TELESCOPE OBSERVATIONS INCLUDING WATER MASERS

Energy Technology Data Exchange (ETDEWEB)

Hoffman, Ian M. [St. Paul' s School, Concord, NH 03301 (United States); Seojin Kim, Stella, E-mail: ihoffman@sps.edu [Current address: Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

2011-12-15

We present new maser emission from {sup 14}NH{sub 3} (9,6) in NGC 7538. Our observations include the known spectral features near v{sub LSR} = -60 km s{sup -1} and -57 km s{sup -1} and several more features extending to -46 km s{sup -1}. In three epochs of observation spanning two months we do not detect any variability in the ammonia masers, in contrast to the >10-fold variability observed in other {sup 14}NH{sub 3} (9,6) masers in the Galaxy over comparable timescales. We also present observations of water masers in all three epochs for which emission is observed over the velocity range -105 km s{sup -1} < v{sub LSR} < -4 km s{sup -1}, including the highest velocity water emission yet observed from NGC 7538. Of the remarkable number of maser species in IRS 1, H{sub 2}O and, now, {sup 14}NH{sub 3} are the only masers known to exhibit emission outside of the velocity range -62 km s{sup -1} < v{sub LSR} < -51 km s{sup -1}. However, we find no significant intensity or velocity correlations between the water emission and ammonia emission. We also present a non-detection in the most sensitive search to date toward any source for emission from the CC{sup 32}S and CC{sup 34}S molecules, indicating an age greater than Almost-Equal-To 10{sup 4} yr for IRS 1-3. We discuss these findings in the context of embedded stellar cores and recent models of the region.

Field visual perspective during autobiographical memory recall is less frequent among patients with schizophrenia.

Science.gov (United States)

Potheegadoo, Jevita; Berna, Fabrice; Cuervo-Lombard, Christine; Danion, Jean-Marie

2013-10-01

There is growing interest in clinical research regarding the visual perspective adopted during memory retrieval, because it reflects individuals' self-attitude towards their memories of past personal events. Several autobiographical memory deficits, including low specificity of personal memories, have been identified in schizophrenia, but visual perspective during autobiographical memory retrieval has not yet been investigated in patients. The aim of this study was therefore to investigate the visual perspective with which patients visualize themselves when recalling autobiographical memories and to assess the specificity of their memories which is a major determinant of visual perspective. Thirty patients with schizophrenia and 30 matched controls recalled personal events from 4 life periods. After each recall, they were asked to report their visual perspective (Field or Observer) associated with the event. The specificity of their memories was assessed by independent raters. Our results showed that patients reported significantly fewer Field perspectives than comparison participants. Patients' memories, whether recalled with Field or Observer perspectives, were less specific and less detailed. Our results indicate that patients with schizophrenia adopt Field perspectives less frequently than comparison participants, and that this may contribute to a weakened sense of the individual of being an actor of his past events, and hence to a reduced sense of self. They suggest that this may be related to low specificity of memories and that all the important aspects involved in re-experiencing autobiographical events are impaired in patients with schizophrenia. © 2013 Elsevier B.V. All rights reserved.

[Effect of acupuncture on pattern-visual evoked potential in rats with monocular visual deprivation].

Science.gov (United States)

Yan, Xing-Ke; Dong, Li-Li; Liu, An-Guo; Wang, Jun-Yan; Ma, Chong-Bing; Zhu, Tian-Tian

2013-08-01

To explore electrophysiology mechanism of acupuncture for treatment and prevention of visual deprivation effect. Eighteen healthy 15-day Evans rats were randomly divided into a normal group, a model group and an acupuncture group, 6 rats in each one. Deprivation amblyopia model was established by monocular eyelid suture in the model group and acupuncture group. Acupuncture was applied at "Jingming" (BL 1), "Chengqi" (ST 1), "Qiuhou" (EX-HN 7) and "Cuanzhu" (BL 2) in the acupuncture group. The bilateral acupoints were selected alternately, one side for a day, and totally 14 days were required. The effect of acupuncture on visual evoked potential in different spatial frequencies was observed. Under three different kinds of spatial frequencies of 2 X 2, 4 X 4 and 8 X 8, compared with normal group, there was obvious visual deprivation effect in the model group where P1 peak latency was delayed (P0.05). Under spatial frequency of 4 X 4, N1-P1 amplitude value was maximum in the normal group and acupuncture group. With this spatial frequency the rat's eye had best resolving ability, indicating it could be the best spatial frequency for rat visual system. The visual system has obvious electrophysiology plasticity in sensitive period. Acupuncture treatment could adjust visual deprivation-induced suppression and slow of visual response in order to antagonism deprivation effect.

Testing of Visual Field with Virtual Reality Goggles in Manual and Visual Grasp Modes

Directory of Open Access Journals (Sweden)

Dariusz Wroblewski

2014-01-01

Full Text Available Automated perimetry is used for the assessment of visual function in a variety of ophthalmic and neurologic diseases. We report development and clinical testing of a compact, head-mounted, and eye-tracking perimeter (VirtualEye that provides a more comfortable test environment than the standard instrumentation. VirtualEye performs the equivalent of a full threshold 24-2 visual field in two modes: (1 manual, with patient response registered with a mouse click, and (2 visual grasp, where the eye tracker senses change in gaze direction as evidence of target acquisition. 59 patients successfully completed the test in manual mode and 40 in visual grasp mode, with 59 undergoing the standard Humphrey field analyzer (HFA testing. Large visual field defects were reliably detected by VirtualEye. Point-by-point comparison between the results obtained with the different modalities indicates: (1 minimal systematic differences between measurements taken in visual grasp and manual modes, (2 the average standard deviation of the difference distributions of about 5 dB, and (3 a systematic shift (of 4–6 dB to lower sensitivities for VirtualEye device, observed mostly in high dB range. The usability survey suggested patients’ acceptance of the head-mounted device. The study appears to validate the concepts of a head-mounted perimeter and the visual grasp mode.

Testing of visual field with virtual reality goggles in manual and visual grasp modes.

Science.gov (United States)

Wroblewski, Dariusz; Francis, Brian A; Sadun, Alfredo; Vakili, Ghazal; Chopra, Vikas

2014-01-01

Automated perimetry is used for the assessment of visual function in a variety of ophthalmic and neurologic diseases. We report development and clinical testing of a compact, head-mounted, and eye-tracking perimeter (VirtualEye) that provides a more comfortable test environment than the standard instrumentation. VirtualEye performs the equivalent of a full threshold 24-2 visual field in two modes: (1) manual, with patient response registered with a mouse click, and (2) visual grasp, where the eye tracker senses change in gaze direction as evidence of target acquisition. 59 patients successfully completed the test in manual mode and 40 in visual grasp mode, with 59 undergoing the standard Humphrey field analyzer (HFA) testing. Large visual field defects were reliably detected by VirtualEye. Point-by-point comparison between the results obtained with the different modalities indicates: (1) minimal systematic differences between measurements taken in visual grasp and manual modes, (2) the average standard deviation of the difference distributions of about 5 dB, and (3) a systematic shift (of 4-6 dB) to lower sensitivities for VirtualEye device, observed mostly in high dB range. The usability survey suggested patients' acceptance of the head-mounted device. The study appears to validate the concepts of a head-mounted perimeter and the visual grasp mode.

VISUALIZATION OF REGISTERED SUBSURFACE ANATOMY

DEFF Research Database (Denmark)

2010-01-01

A system and method for visualization of subsurface anatomy includes obtaining a first image from a first camera and a second image from a second camera or a second channel of the first camera, where the first and second images contain shared anatomical structures. The second camera and the secon....... A visual interface displays the registered visualization of the first and second images. The system and method are particularly useful for imaging during minimally invasive surgery, such as robotic surgery....

Community screening for visual impairment in older people.

Science.gov (United States)

Clarke, Emily L; Evans, Jennifer R; Smeeth, Liam

2018-02-20

a brief health assessment including one question about vision (standard care). People given the detailed health assessment had a similar risk of visual impairment (visual acuity worse than 6/18 in either eye) at follow-up compared with people given the brief assessment (RR 1.07, 95% CI 0.84 to 1.36, 1807 participants, moderate-certainty evidence). The mean composite score of the VFQ-25 was 86.0 in the group that underwent visual acuity screening compared with 85.6 in the standard care group, a difference of 0.40 (95% CI -1.70 to 2.50, 1807 participants, high-certainty evidence). The evidence from RCTs undertaken to date does not support vision screening for older people living independently in a community setting, whether in isolation or as part of a multi-component screening package. This is true for screening programmes involving questions about visual problems, or direct measurements of visual acuity.The most likely reason for this negative review is that the populations within the trials often did not take up the offered intervention as a result of the vision screening and large proportions of those who did not have vision screening appeared to seek their own intervention. Also, trials that use questions about vision have a lower sensitivity and specificity than formal visual acuity testing. Given the importance of visual impairment among older people, further research into strategies to improve vision of older people is needed. The effectiveness of an optimised primary care-based screening intervention that overcomes possible factors contributing to the observed lack of benefit in trials to date warrants assessment; trials should consider including more dependent participants, rather than those living independently in the community.

Visualization rhetoric: framing effects in narrative visualization.

Science.gov (United States)

Hullman, Jessica; Diakopoulos, Nicholas

2011-12-01

Narrative visualizations combine conventions of communicative and exploratory information visualization to convey an intended story. We demonstrate visualization rhetoric as an analytical framework for understanding how design techniques that prioritize particular interpretations in visualizations that "tell a story" can significantly affect end-user interpretation. We draw a parallel between narrative visualization interpretation and evidence from framing studies in political messaging, decision-making, and literary studies. Devices for understanding the rhetorical nature of narrative information visualizations are presented, informed by the rigorous application of concepts from critical theory, semiotics, journalism, and political theory. We draw attention to how design tactics represent additions or omissions of information at various levels-the data, visual representation, textual annotations, and interactivity-and how visualizations denote and connote phenomena with reference to unstated viewing conventions and codes. Classes of rhetorical techniques identified via a systematic analysis of recent narrative visualizations are presented, and characterized according to their rhetorical contribution to the visualization. We describe how designers and researchers can benefit from the potentially positive aspects of visualization rhetoric in designing engaging, layered narrative visualizations and how our framework can shed light on how a visualization design prioritizes specific interpretations. We identify areas where future inquiry into visualization rhetoric can improve understanding of visualization interpretation. © 2011 IEEE

A New Visual Stimulation Program for Improving Visual Acuity in Children with Visual Impairment: A Pilot Study

Science.gov (United States)

Tsai, Li-Ting; Hsu, Jung-Lung; Wu, Chien-Te; Chen, Chia-Ching; Su, Yu-Chin

2016-01-01

The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS) program combining checkerboard pattern reversal (passive stimulation) with oddball stimuli (attentional modulation) for improving the visual acuity (VA) of visually impaired (VI) children and children with amblyopia and additional developmental problems. Six children (three females, three males; mean age = 3.9 ± 2.3 years) with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week) of at least eight sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards), visual evoked potential (VEP), and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ) were carried out before and after the VS program. Significant gains in VA were found after the VS training [VA = 1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z = –2.20, asymptotic significance (2-tailed) = 0.028]. No significant changes were observed in the FVQ assessment [92.8 ± 12.6 to 100.8 ±SD = 15.4, Z = –1.46, asymptotic significance (2-tailed) = 0.144]. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders. PMID:27148014

A New Visual Stimulation Program for Improving Visual Acuity in Children with Visual Impairment: A Pilot Study.

Science.gov (United States)

Tsai, Li-Ting; Hsu, Jung-Lung; Wu, Chien-Te; Chen, Chia-Ching; Su, Yu-Chin

2016-01-01

The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS) program combining checkerboard pattern reversal (passive stimulation) with oddball stimuli (attentional modulation) for improving the visual acuity (VA) of visually impaired (VI) children and children with amblyopia and additional developmental problems. Six children (three females, three males; mean age = 3.9 ± 2.3 years) with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week) of at least eight sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards), visual evoked potential (VEP), and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ) were carried out before and after the VS program. Significant gains in VA were found after the VS training [VA = 1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z = -2.20, asymptotic significance (2-tailed) = 0.028]. No significant changes were observed in the FVQ assessment [92.8 ± 12.6 to 100.8 ±SD = 15.4, Z = -1.46, asymptotic significance (2-tailed) = 0.144]. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders.

A new visual stimulation program for improving visual acuity in children with visual impairment: a pilot study

Directory of Open Access Journals (Sweden)

Li-Ting eTsai

2016-04-01

Full Text Available The purpose of this study was to investigate the effectiveness of visual rehabilitation of a computer-based visual stimulation (VS program combining checkerboard pattern reversal (passive stimulation with oddball stimuli (attentional modulation for improving the visual acuity (VA of visually impaired (VI children and children with amblyopia and additional developmental problems. Six children (3 females, 3 males; mean age = 3.9 ± 2.3 years with impaired VA caused by deficits along the anterior and/or posterior visual pathways were recruited. Participants received eight rounds of VS training (two rounds per week of at least 8 sessions per round. Each session consisted of stimulation with 200 or 300 pattern reversals. Assessments of VA (assessed with the Lea symbol VA test or Teller VA cards, visual evoked potential (VEP, and functional vision (assessed with the Chinese-version Functional Vision Questionnaire, FVQ were carried out before and after the VS program. Significant gains in VA were found after the VS training (VA=1.05 logMAR ± 0.80 to 0.61 logMAR ± 0.53, Z=-2.20, asymptotic significance (2-tailed =0.028. No significant changes were observed in the FVQ assessment (92.8 ± 12.6 to 100.8 ± SD=15.4, Z=-1.46, asymptotic significance (2-tailed = 0.144. VEP measurement showed improvement in P100 latency and amplitude or integration of the waveform in two participants. Our results indicate that a computer-based VS program with passive checkerboard stimulation, oddball stimulus design, and interesting auditory feedback could be considered as a potential intervention option to improve the VA of a wide age range of VI children and children with impaired VA combined with other neurological disorders.

Visual Equivalence and Amodal Completion in Cuttlefish

OpenAIRE

Lin, I-Rong; Chiao, Chuan-Chin

2017-01-01

Modern cephalopods are notably the most intelligent invertebrates and this is accompanied by keen vision. Despite extensive studies investigating the visual systems of cephalopods, little is known about their visual perception and object recognition. In the present study, we investigated the visual processing of the cuttlefish Sepia pharaonis, including visual equivalence and amodal completion. Cuttlefish were trained to discriminate images of shrimp and fish using the operant conditioning pa...

A Survey on Sensor Coverage and Visual Data Capturing/Processing/Transmission in Wireless Visual Sensor Networks

Directory of Open Access Journals (Sweden)

Florence G. H. Yap

2014-02-01

Full Text Available Wireless Visual Sensor Networks (WVSNs where camera-equipped sensor nodes can capture, process and transmit image/video information have become an important new research area. As compared to the traditional wireless sensor networks (WSNs that can only transmit scalar information (e.g., temperature, the visual data in WVSNs enable much wider applications, such as visual security surveillance and visual wildlife monitoring. However, as compared to the scalar data in WSNs, visual data is much bigger and more complicated so intelligent schemes are required to capture/process/ transmit visual data in limited resources (hardware capability and bandwidth WVSNs. WVSNs introduce new multi-disciplinary research opportunities of topics that include visual sensor hardware, image and multimedia capture and processing, wireless communication and networking. In this paper, we survey existing research efforts on the visual sensor hardware, visual sensor coverage/deployment, and visual data capture/ processing/transmission issues in WVSNs. We conclude that WVSN research is still in an early age and there are still many open issues that have not been fully addressed. More new novel multi-disciplinary, cross-layered, distributed and collaborative solutions should be devised to tackle these challenging issues in WVSNs.

R Aqr observing campaign

Science.gov (United States)

Waagen, Elizabeth O.

2016-01-01

Dr. George Wallerstein (University of Washington) has requested AAVSO coverage of the long period/symbiotic variable R Aquarii beginning immediately in support of high resolution spectroscopic observations planned for 2016 January 19 and 21. Several other astronomers, including Drs. Lee Anne Willson (Iowa State University), Ulisse Munari (INAF, Astronomical Observatory of Padua, Italy), and Fred Walter (Stony Brook University) are studying R Aqr closely and additional spectroscopic and other observations are planned for the near future. R Aqr is both a Mira (M) and a symbiotic (ZAND) - it is a close binary system consisting of a hot star and a late-type star (the Mira), both enveloped in nebulosity. As a result, the very interesting light curve shows not only the Mira pulsation but also complex eclipse behavior as the two stars interact. The period of Mira variation is 387.0 days; the eclipse period is 43.6-44 years. The cause of the eclipse is unknown; several theories h! ave been proposed, including a focused accretion stream, a disk or cloud around the secondary, and a triggered mass loss that produces an opaque cloud. Careful investigation of this upcoming event should help to resolve this question. The last eclipse of R Aqr was in 1978. The next eclipse is predicted for 2022, but may be early. The current behavior of R Aqr suggests that the eclipse, which lasts for several years, may either be beginning or its beginning may be imminent. R Aqr was at minimum in early December 2015 at magnitude V=11.4, and is currently at visual magnitude 11.0. During this phase of the approximately 44-year eclipse cycle, at maximum it may be as bright as V 6.0-6.5 but is not expected to become brighter. Beginning immediately, nightly BVRI CCD and DSLR photometry and visual observations are requested. As R Aqr brightens towards maximum and is in range, PEP observations are also requested. Ongoing spectroscopy over the next several years will be interesting to see as the system

Visual working memory contaminates perception

OpenAIRE

Kang, Min-Suk; Hong, Sang Wook; Blake, Randolph; Woodman, Geoffrey F.

2011-01-01

Indirect evidence suggests that the contents of visual working memory may be maintained within sensory areas early in the visual hierarchy. We tested this possibility using a well-studied motion repulsion phenomenon in which perception of one direction of motion is distorted when another direction of motion is viewed simultaneously. We found that observers misperceived the actual direction of motion of a single motion stimulus if, while viewing that stimulus, they were holding a different mot...

Observer's Mood Manipulates Level of Visual Processing: Evidence from Face and Nonface Stimuli

Directory of Open Access Journals (Sweden)

Setareh Mokhtari

2011-05-01

Full Text Available For investigating the effect of observer's mood on level of processing of visual stimuli, happy or sad mood was induced in two groups of participants through asking them to deliberate one of their sad or happy memories while listening to a congruent piece of music. This was followed by a computer-based task that required counting some features (arcs or lines of emotional schematic faces (with either sad or happy expressions for group 1, and counting same features of meaningless combined shapes for group 2. Reaction time analysis indicated there is a significant difference in RTs after listening to the sad music compared with happy music for group 1; participants with sad moods were significantly slower when they worked on local levels of schematic faces with sad expressions. Happy moods did not show any specific effect on reaction time of participants who were working on local details of emotionally expressive faces. Sad moods or happy moods had no significant effect on reaction time of working on parts of meaningless shapes. It seems that sad moods as a contextual factor elevate the ability of sad expression to grab the attention and block fast access to the local parts of the holistic meaningful shapes.

Visualizing conserved gene location across microbe genomes

Science.gov (United States)

Shaw, Chris D.

2009-01-01

This paper introduces an analysis-based zoomable visualization technique for displaying the location of genes across many related species of microbes. The purpose of this visualizatiuon is to enable a biologist to examine the layout of genes in the organism of interest with respect to the gene organization of related organisms. During the genomic annotation process, the ability to observe gene organization in common with previously annotated genomes can help a biologist better confirm the structure and function of newly analyzed microbe DNA sequences. We have developed a visualization and analysis tool that enables the biologist to observe and examine gene organization among genomes, in the context of the primary sequence of interest. This paper describes the visualization and analysis steps, and presents a case study using a number of Rickettsia genomes.

Visual observations of fuel disruption in in-pile LMFBR accident experiments

International Nuclear Information System (INIS)

Wright, S.A.; Mast, P.K.

1982-01-01

Sandia National Laboratories has been investigating initiation phase phenomena in a series of Fuel Disruption (FD) experiments since 1977. In this program high speed cinematography is used to observe fuel disruption in in-pile experiments that simulate loss of flow accidents. Thus, these experiments provide high resolution measurements of initial fuel and clad motion with prototypic materials and prototypic heating conditions. The main objective of the FD experiment is to determine the timing (relative to fuel temperature) and the mode of fuel disruption under LOF heating conditions. Observed modes of disruption include fuel swelling, solid state breakup, cracking, ejection of a molten fuel jet, slumping, and rapid expansion of small particles. Because the temperature and character of the fuel at disruption are known, disruption can be correlated with the mechanisms driving the disruption such as fuel vapor pressure, molten fuel expansion, fission gases, and impurity gases

Art-Science-Technology collaboration through immersive, interactive 3D visualization

Science.gov (United States)

Kellogg, L. H.

2014-12-01

At the W. M. Keck Center for Active Visualization in Earth Sciences (KeckCAVES), a group of geoscientists and computer scientists collaborate to develop and use of interactive, immersive, 3D visualization technology to view, manipulate, and interpret data for scientific research. The visual impact of immersion in a CAVE environment can be extremely compelling, and from the outset KeckCAVES scientists have collaborated with artists to bring this technology to creative works, including theater and dance performance, installations, and gamification. The first full-fledged collaboration designed and produced a performance called "Collapse: Suddenly falling down", choreographed by Della Davidson, which investigated the human and cultural response to natural and man-made disasters. Scientific data (lidar scans of disaster sites, such as landslides and mine collapses) were fully integrated into the performance by the Sideshow Physical Theatre. This presentation will discuss both the technological and creative characteristics of, and lessons learned from the collaboration. Many parallels between the artistic and scientific process emerged. We observed that both artists and scientists set out to investigate a topic, solve a problem, or answer a question. Refining that question or problem is an essential part of both the creative and scientific workflow. Both artists and scientists seek understanding (in this case understanding of natural disasters). Differences also emerged; the group noted that the scientists sought clarity (including but not limited to quantitative measurements) as a means to understanding, while the artists embraced ambiguity, also as a means to understanding. Subsequent art-science-technology collaborations have responded to evolving technology for visualization and include gamification as a means to explore data, and use of augmented reality for informal learning in museum settings.

Spectators & spectacles: nurses, midwives and visuality.

Science.gov (United States)

Barnard, Alan G; Sinclair, Marlene

2006-09-01

In this paper we reflect on how linear perspective vision influences the practice of nurses and midwives and to advance understanding of clinical practice in technologically intensive environments through examination of drawings by nurses and midwives and through critical analysis. There is increasing emphasis on vision in Western culture, and both nurses and midwives spend a great deal of time observing their clinical environment(s). Healthcare practitioners work increasingly in image-based realities and nurses rely on visual skills. Vision and visual representation are central to our practice and are important to examine because we look often at technology to assess people and care. The world in which we practise is one of meaning(s). Technological development is transformative in nature and produces changes that alter the way(s) we give care. Amongst all this change, it is unclear how we practise in environments characterized by increasing technology and it is unknown how nursing and midwifery practice alter as a result. Simple drawings included in this paper highlight an important and shared experience of clinical practice(s). They emphasize the importance and scope of the visual sense and expose practitioner behaviour that has enormous implications for current and future professional development and person-focussed care provision. Experiences described in this paper require further examination and highlight substantial changes to nurse-patient relationships, health care and the way we practise.

Object-based attention underlies the rehearsal of feature binding in visual working memory.

Science.gov (United States)

Shen, Mowei; Huang, Xiang; Gao, Zaifeng

2015-04-01

Feature binding is a core concept in many research fields, including the study of working memory (WM). Over the past decade, it has been debated whether keeping the feature binding in visual WM consumes more visual attention than the constituent single features. Previous studies have only explored the contribution of domain-general attention or space-based attention in the binding process; no study so far has explored the role of object-based attention in retaining binding in visual WM. We hypothesized that object-based attention underlay the mechanism of rehearsing feature binding in visual WM. Therefore, during the maintenance phase of a visual WM task, we inserted a secondary mental rotation (Experiments 1-3), transparent motion (Experiment 4), or an object-based feature report task (Experiment 5) to consume the object-based attention available for binding. In line with the prediction of the object-based attention hypothesis, Experiments 1-5 revealed a more significant impairment for binding than for constituent single features. However, this selective binding impairment was not observed when inserting a space-based visual search task (Experiment 6). We conclude that object-based attention underlies the rehearsal of binding representation in visual WM. (c) 2015 APA, all rights reserved.

Visualization in medicine and life sciences

International Nuclear Information System (INIS)

Linsen, L.; Hamann, B.

2008-01-01

Visualization technology is becoming increasingly important for medical and biomedical data processing and analysis. This technology complements traditional image processing methods as it allows scientists to visually interact with large, high-resolution three-dimensional image data, for example. Furthermore, an ever increasing number of new data acquisition methods are being used in medicine and the life sciences, in particular in genomics and proteomics. This book discusses some of the latest visualization techniques and systems for effective analysis of such diverse, large, complex, and multi-source data. Experts from all over the world were invited to participate in a workshop held in July 2006 on the island Ruegen in Germany. About 40 participants presented state-of-the-art research on the topic. Research and survey papers have been solicited and carefully refereed, resulting in this collection. The topics covered include Segmentation and Feature Detection, Surface Extraction, Volume Visualization, Graph and Network Visualization, Visual Data Exploration, Multivariate and Multidimensional Data Visualization, Large Data Visualization. (orig.)

Eye vergence responses during a visual memory task.

Science.gov (United States)

Solé Puig, Maria; Romeo, August; Cañete Crespillo, Jose; Supèr, Hans

2017-02-08

In a previous report it was shown that covertly attending visual stimuli produce small convergence of the eyes, and that visual stimuli can give rise to different modulations of the angle of eye vergence, depending on their power to capture attention. Working memory is highly dependent on attention. Therefore, in this study we assessed vergence responses in a memory task. Participants scanned a set of 8 or 12 images for 10 s, and thereafter were presented with a series of single images. One half were repeat images - that is, they belonged to the initial set - and the other half were novel images. Participants were asked to indicate whether or not the images were included in the initial image set. We observed that eyes converge during scanning the set of images and during the presentation of the single images. The convergence was stronger for remembered images compared with the vergence for nonremembered images. Modulation in pupil size did not correspond to behavioural responses. The correspondence between vergence and coding/retrieval processes of memory strengthen the idea of a role for vergence in attention processing of visual information.

A neural theory of visual attention

DEFF Research Database (Denmark)

Bundesen, Claus; Habekost, Thomas; Kyllingsbæk, Søren

2005-01-01

A neural theory of visual attention (NTVA) is presented. NTVA is a neural interpretation of C. Bundesen's (1990) theory of visual attention (TVA). In NTVA, visual processing capacity is distributed across stimuli by dynamic remapping of receptive fields of cortical cells such that more processing...... resources (cells) are devoted to behaviorally important objects than to less important ones. By use of the same basic equations used in TVA, NTVA accounts for a wide range of known attentional effects in human performance (reaction times and error rates) and a wide range of effects observed in firing rates...

Do Visually Impaired People Develop Superior Smell Ability?

Science.gov (United States)

Majchrzak, Dorota; Eberhard, Julia; Kalaus, Barbara; Wagner, Karl-Heinz

2017-10-01

It is well known that visually impaired people perform better in orientation by sound than sighted individuals, but it is not clear whether this enhanced awareness also extends to other senses. Therefore, the aim of this study was to observe whether visually impaired subjects develop superior abilities in olfactory perception to compensate for their lack of vision. We investigated the odor perception of visually impaired individuals aged 7 to 89 ( n = 99; 52 women, 47 men) and compared them with subjects of a control group aged 8 to 82 years ( n = 100; 45 women, 55 men) without any visual impairment. The participants were evaluated by Sniffin' Sticks odor identification and discrimination test. Identification ability was assessed for 16 common odors presented in felt-tip pens. In the odor discrimination task, subjects had to determine which of three pens in 16 triplets had a different odor. The median number of correctly identified odorant pens in both groups was the same, 13 of the offered 16. In the discrimination test, there was also no significant difference observed. Gender did not influence results. Age-related changes were observed in both groups with olfactory perception decreasing after the age of 51. We could not confirm that visually impaired people were better in smell identification and discrimination ability than sighted individuals.

Creating Effective Data Visualizations - Lecture 1

CERN Multimedia

CERN. Geneva

2017-01-01

In this course I aim to give an overview of data visualisation as a field, including many of the important theoretical groundings in data visualization. We will explore the different ways of representing visual information, and the strengths/weaknesses of those approaches. Using real-world case studies, I will demonstrate techniques and best practices for visualizing complex multi-dimensional data common to high energy physics and other fields.

Creating Effective Data Visualizations - Lecture 2

CERN Multimedia

CERN. Geneva

2017-01-01

In this course I aim to give an overview of data visualisation as a field, including many of the important theoretical groundings in data visualization. We will explore the different ways of representing visual information, and the strengths/weaknesses of those approaches. Using real-world case studies, I will demonstrate techniques and best practices for visualizing complex multi-dimensional data common to high energy physics and other fields.

The Visual Cultures of Showing ‘Nourishment’ in a Glass Case

DEFF Research Database (Denmark)

Buhl, Mie

2016-01-01

by placing it where you cannot touch it, eat it, smell it, taste it – in other words of turning it into an exhibition item? By removing the characteristics from food, it would in all probability be even more difficult to attain the purpose of exhibiting it: to sell it to students and staff. My discussion...... of the phenomenon of nourishment in glass cases draws on approaches developed and discussed as visual culture methodology. With a visual culture approach, visuals work as constructions of visual knowledge and as indicators of the relation between an observer's glance and the phenomenon observed. The implication...

Perceptual geometry of space and form: visual perception of natural scenes and their virtual representation

Science.gov (United States)

Assadi, Amir H.

2001-11-01

Perceptual geometry is an emerging field of interdisciplinary research whose objectives focus on study of geometry from the perspective of visual perception, and in turn, apply such geometric findings to the ecological study of vision. Perceptual geometry attempts to answer fundamental questions in perception of form and representation of space through synthesis of cognitive and biological theories of visual perception with geometric theories of the physical world. Perception of form and space are among fundamental problems in vision science. In recent cognitive and computational models of human perception, natural scenes are used systematically as preferred visual stimuli. Among key problems in perception of form and space, we have examined perception of geometry of natural surfaces and curves, e.g. as in the observer's environment. Besides a systematic mathematical foundation for a remarkably general framework, the advantages of the Gestalt theory of natural surfaces include a concrete computational approach to simulate or recreate images whose geometric invariants and quantities might be perceived and estimated by an observer. The latter is at the very foundation of understanding the nature of perception of space and form, and the (computer graphics) problem of rendering scenes to visually invoke virtual presence.

High resolution esophageal manometry--the switch from "intuitive" visual interpretation to Chicago classification.

Science.gov (United States)

Srinivas, M; Balakumaran, T A; Palaniappan, S; Srinivasan, Vijaya; Batcha, M; Venkataraman, Jayanthi

2014-03-01

High resolution esophageal manometry (HREM) has been interpreted all along by visual interpretation of color plots until the recent introduction of Chicago classification which categorises HREM using objective measurements. It compares HREM diagnosis of esophageal motor disorders by visual interpretation and Chicago classification. Using software Trace 1.2v, 77 consecutive tracings diagnosed by visual interpretation were re-analyzed by Chicago classification and findings compared for concordance between the two systems of interpretation. Kappa agreement rate between the two observations was determined. There were 57 males (74 %) and cohort median age was 41 years (range: 14-83 years). Majority of the referrals were for gastroesophageal reflux disease, dysphagia and achalasia. By "intuitive" visual interpretation, the tracing were reported as normal in 45 (58.4 %), achalasia 14 (18.2 %), ineffective esophageal motility 3 (3.9 %), nutcracker esophagus 11 (14.3 %) and nonspecific motility changes 4 (5.2 %). By Chicago classification, there was 100 % agreement (Kappa 1) for achalasia (type 1: 9; type 2: 5) and ineffective esophageal motility ("failed peristalsis" on visual interpretation). Normal esophageal motility, nutcracker esophagus and nonspecific motility disorder on visual interpretation were reclassified as rapid contraction and esophagogastric junction (EGJ) outflow obstruction by Chicago classification. Chicago classification identified distinct clinical phenotypes including EGJ outflow obstruction not identified by visual interpretation. A significant number of unclassified HREM by visual interpretation were also classified by it.

Three-dimensional Imaging, Visualization, and Display

CERN Document Server

Javidi, Bahram; Son, Jung-Young

2009-01-01

Three-Dimensional Imaging, Visualization, and Display describes recent developments, as well as the prospects and challenges facing 3D imaging, visualization, and display systems and devices. With the rapid advances in electronics, hardware, and software, 3D imaging techniques can now be implemented with commercially available components and can be used for many applications. This volume discusses the state-of-the-art in 3D display and visualization technologies, including binocular, multi-view, holographic, and image reproduction and capture techniques. It also covers 3D optical systems, 3D display instruments, 3D imaging applications, and details several attractive methods for producing 3D moving pictures. This book integrates the background material with new advances and applications in the field, and the available online supplement will include full color videos of 3D display systems. Three-Dimensional Imaging, Visualization, and Display is suitable for electrical engineers, computer scientists, optical e...

Visual exploration of images

Science.gov (United States)

Suaste-Gomez, Ernesto; Leybon, Jaime I.; Rodriguez, D.

1998-07-01

Visual scanpath has been an important work applied in neuro- ophthalmic and psychological studies. This is because it has been working like a tool to validate some pathologies such as visual perception in color or black/white images; color blindness; etc. On the other hand, this tool has reached a big field of applications such as marketing. The scanpath over a specific picture, shows the observer interest in color, shapes, letter size, etc.; even tough the picture be among a group of images, this tool has demonstrated to be helpful to catch people interest over a specific advertisement.

Peripheral Vision of Youths with Low Vision: Motion Perception, Crowding, and Visual Search

Science.gov (United States)

Tadin, Duje; Nyquist, Jeffrey B.; Lusk, Kelly E.; Corn, Anne L.; Lappin, Joseph S.

2012-01-01

Purpose. Effects of low vision on peripheral visual function are poorly understood, especially in children whose visual skills are still developing. The aim of this study was to measure both central and peripheral visual functions in youths with typical and low vision. Of specific interest was the extent to which measures of foveal function predict performance of peripheral tasks. Methods. We assessed central and peripheral visual functions in youths with typical vision (n = 7, ages 10–17) and low vision (n = 24, ages 9–18). Experimental measures used both static and moving stimuli and included visual crowding, visual search, motion acuity, motion direction discrimination, and multitarget motion comparison. Results. In most tasks, visual function was impaired in youths with low vision. Substantial differences, however, were found both between participant groups and, importantly, across different tasks within participant groups. Foveal visual acuity was a modest predictor of peripheral form vision and motion sensitivity in either the central or peripheral field. Despite exhibiting normal motion discriminations in fovea, motion sensitivity of youths with low vision deteriorated in the periphery. This contrasted with typically sighted participants, who showed improved motion sensitivity with increasing eccentricity. Visual search was greatly impaired in youths with low vision. Conclusions. Our results reveal a complex pattern of visual deficits in peripheral vision and indicate a significant role of attentional mechanisms in observed impairments. These deficits were not adequately captured by measures of foveal function, arguing for the importance of independently assessing peripheral visual function. PMID:22836766

Training on Movement Figure-Ground Discrimination Remediates Low-Level Visual Timing Deficits in the Dorsal Stream, Improving High-Level Cognitive Functioning, Including Attention, Reading Fluency, and Working Memory

Directory of Open Access Journals (Sweden)

Teri Lawton

2017-05-01

Full Text Available The purpose of this study was to determine whether neurotraining to discriminate a moving test pattern relative to a stationary background, figure-ground discrimination, improves vision and cognitive functioning in dyslexics, as well as typically-developing normal students. We predict that improving the speed and sensitivity of figure-ground movement discrimination (PATH to Reading neurotraining acts to remediate visual timing deficits in the dorsal stream, thereby improving processing speed, reading fluency, and the executive control functions of attention and working memory in both dyslexic and normal students who had PATH neurotraining more than in those students who had no neurotraining. This prediction was evaluated by measuring whether dyslexic and normal students improved on standardized tests of cognitive skills following neurotraining exercises, more than following computer-based guided reading (Raz-Kids (RK. The neurotraining used in this study was visually-based training designed to improve magnocellular function at both low and high levels in the dorsal stream: the input to the executive control networks coding working memory and attention. This approach represents a paradigm shift from the phonologically-based treatment for dyslexia, which concentrates on high-level speech and reading areas. This randomized controlled-validation study was conducted by training the entire second and third grade classrooms (42 students for 30 min twice a week before guided reading. Standardized tests were administered at the beginning and end of 12-weeks of intervention training to evaluate improvements in academic skills. Only movement-discrimination training remediated both low-level visual timing deficits and high-level cognitive functioning, including selective and sustained attention, reading fluency and working memory for both dyslexic and normal students. Remediating visual timing deficits in the dorsal stream revealed the causal role of visual

Training on Movement Figure-Ground Discrimination Remediates Low-Level Visual Timing Deficits in the Dorsal Stream, Improving High-Level Cognitive Functioning, Including Attention, Reading Fluency, and Working Memory.

Science.gov (United States)

Lawton, Teri; Shelley-Tremblay, John

2017-01-01

The purpose of this study was to determine whether neurotraining to discriminate a moving test pattern relative to a stationary background, figure-ground discrimination, improves vision and cognitive functioning in dyslexics, as well as typically-developing normal students. We predict that improving the speed and sensitivity of figure-ground movement discrimination ( PATH to Reading neurotraining) acts to remediate visual timing deficits in the dorsal stream, thereby improving processing speed, reading fluency, and the executive control functions of attention and working memory in both dyslexic and normal students who had PATH neurotraining more than in those students who had no neurotraining. This prediction was evaluated by measuring whether dyslexic and normal students improved on standardized tests of cognitive skills following neurotraining exercises, more than following computer-based guided reading ( Raz-Kids ( RK )). The neurotraining used in this study was visually-based training designed to improve magnocellular function at both low and high levels in the dorsal stream: the input to the executive control networks coding working memory and attention. This approach represents a paradigm shift from the phonologically-based treatment for dyslexia, which concentrates on high-level speech and reading areas. This randomized controlled-validation study was conducted by training the entire second and third grade classrooms (42 students) for 30 min twice a week before guided reading. Standardized tests were administered at the beginning and end of 12-weeks of intervention training to evaluate improvements in academic skills. Only movement-discrimination training remediated both low-level visual timing deficits and high-level cognitive functioning, including selective and sustained attention, reading fluency and working memory for both dyslexic and normal students. Remediating visual timing deficits in the dorsal stream revealed the causal role of visual movement

Training on Movement Figure-Ground Discrimination Remediates Low-Level Visual Timing Deficits in the Dorsal Stream, Improving High-Level Cognitive Functioning, Including Attention, Reading Fluency, and Working Memory

Science.gov (United States)

Lawton, Teri; Shelley-Tremblay, John

2017-01-01

The purpose of this study was to determine whether neurotraining to discriminate a moving test pattern relative to a stationary background, figure-ground discrimination, improves vision and cognitive functioning in dyslexics, as well as typically-developing normal students. We predict that improving the speed and sensitivity of figure-ground movement discrimination (PATH to Reading neurotraining) acts to remediate visual timing deficits in the dorsal stream, thereby improving processing speed, reading fluency, and the executive control functions of attention and working memory in both dyslexic and normal students who had PATH neurotraining more than in those students who had no neurotraining. This prediction was evaluated by measuring whether dyslexic and normal students improved on standardized tests of cognitive skills following neurotraining exercises, more than following computer-based guided reading (Raz-Kids (RK)). The neurotraining used in this study was visually-based training designed to improve magnocellular function at both low and high levels in the dorsal stream: the input to the executive control networks coding working memory and attention. This approach represents a paradigm shift from the phonologically-based treatment for dyslexia, which concentrates on high-level speech and reading areas. This randomized controlled-validation study was conducted by training the entire second and third grade classrooms (42 students) for 30 min twice a week before guided reading. Standardized tests were administered at the beginning and end of 12-weeks of intervention training to evaluate improvements in academic skills. Only movement-discrimination training remediated both low-level visual timing deficits and high-level cognitive functioning, including selective and sustained attention, reading fluency and working memory for both dyslexic and normal students. Remediating visual timing deficits in the dorsal stream revealed the causal role of visual movement

Cluster Oriented Spatio Temporal Multidimensional Data Visualization of Earthquakes in Indonesia

Directory of Open Access Journals (Sweden)

Mohammad Nur Shodiq

2016-03-01

Full Text Available Spatio temporal data clustering is challenge task. The result of clustering data are utilized to investigate the seismic parameters. Seismic parameters are used to describe the characteristics of earthquake behavior. One of the effective technique to study multidimensional spatio temporal data is visualization. But, visualization of multidimensional data is complicated problem. Because, this analysis consists of observed data cluster and seismic parameters. In this paper, we propose a visualization system, called as IES (Indonesia Earthquake System, for cluster analysis, spatio temporal analysis, and visualize the multidimensional data of seismic parameters. We analyze the cluster analysis by using automatic clustering, that consists of get optimal number of cluster and Hierarchical K-means clustering. We explore the visual cluster and multidimensional data in low dimensional space visualization. We made experiment with observed data, that consists of seismic data around Indonesian archipelago during 2004 to 2014. Keywords: Clustering, visualization, multidimensional data, seismic parameters.

Op art and visual perception.

Science.gov (United States)

Wade, N J

1978-01-01

An attempt is made to list the visual phenomena exploited in op art. These include moire frinlude moiré fringes, afterimages, Hermann grid effects, Gestalt grouping principles, blurring and movement due to astigmatic fluctuations in accommodation, scintillation and streaming possibly due to eye movements, and visual persistence. The historical origins of these phenomena are also noted.

Attentional Capture to a Singleton Distractor Degrades Visual Marking in Visual Search

Directory of Open Access Journals (Sweden)

Kenji Yamauchi

2017-05-01

Full Text Available Visual search is easier after observing some distractors in advance; it is as if the previewed distractors were excluded from the search. This effect is referred to as the preview benefit, and a memory template that visually marks the old locations of the distractors is thought to help in prioritizing the locations of newly presented items. One remaining question is whether the presence of a conspicuous item during the sequential shift of attention within the new items reduces this preview benefit. To address this issue, we combined the above preview search and a conventional visual search paradigm using a singleton distractor and examined whether the search performance was affected by the presence of the singleton. The results showed that the slope of reaction time as a function of set size became steeper in the presence of a singleton, indicating that the singleton distractor reduced the preview benefit. Furthermore, this degradation effect was positively correlated with the degree of conventional attentional capture to a singleton measured in a separate experiment with simultaneous search. These findings suggest that the mechanism of visual marking shares common attentional resources with the search process.

Visualization needs and techniques for astrophysical simulations

International Nuclear Information System (INIS)

Kapferer, W; Riser, T

2008-01-01

Numerical simulations have evolved continuously towards being an important field in astrophysics, equivalent to theory and observation. Due to the enormous developments in computer sciences, both hardware- and software-architecture, state-of-the-art simulations produce huge amounts of raw data with increasing complexity. In this paper some aspects of problems in the field of visualization in numerical astrophysics in combination with possible solutions are given. Commonly used visualization packages along with a newly developed approach to real-time visualization, incorporating shader programming to uncover the computational power of modern graphics cards, are presented. With these techniques at hand, real-time visualizations help scientists to understand the coherences in the results of their numerical simulations. Furthermore a fundamental problem in data analysis, i.e. coverage of metadata on how a visualization was created, is highlighted.

Improvement of visual acuity and VEP after optic nerve contusion by NGF and its safety analysis

Directory of Open Access Journals (Sweden)

Ming Zhao

2018-02-01

Full Text Available AIM:To investigate the effect of neuropathic factor(NGFon visual acuity and visual evoked potential(VEPin patients with optic nerve contusion. METHODS:Totally 78 patients(78 eyeswith optic nerve contusion were selected. From January 2013 to June 2016, 39 cases(39 eyeswere divided into observation group and control group respectively according to the random number table method. Prednisone, vitamins and mecobalamin tablets treatment were given to both groups, based on that, the observation group was given NGF treatment, continuous treatment of 2 courses(21d for a course of treatment. RESULTS: There was no significant difference in visual field defect and visual field sensitivity between the observation group and the control group before treatment(P>0.05. After treatment, the visual field defect degree of the observation group was smaller, the visual field sensitivity was better than that of the control group(PP>0.05. After treatment, the P100 wave latency of the observation group was significantly shorter than that of the control group(PPPCONCLUSION: NGF treatment for optic nerve contusion can significantly improve the patient's visual acuity, VEP indicators, reduce visual field defects, improve visual field sensitivity.

Evaluation of visual skills in sedentary and active work environments ...

African Journals Online (AJOL)

motor skills. Visual-motor skills encompass three essential ocular motor skills, namely focusing, eye-hand coordination and tracking. The aspects of the visual perceptual process include visual memory and visualization. This study aims to ...

Visualization Tools for Teaching Computer Security

Science.gov (United States)

Yuan, Xiaohong; Vega, Percy; Qadah, Yaseen; Archer, Ricky; Yu, Huiming; Xu, Jinsheng

2010-01-01

Using animated visualization tools has been an important teaching approach in computer science education. We have developed three visualization and animation tools that demonstrate various information security concepts and actively engage learners. The information security concepts illustrated include: packet sniffer and related computer network…

Infant visual attention and object recognition.

Science.gov (United States)

Reynolds, Greg D

2015-05-15

This paper explores the role visual attention plays in the recognition of objects in infancy. Research and theory on the development of infant attention and recognition memory are reviewed in three major sections. The first section reviews some of the major findings and theory emerging from a rich tradition of behavioral research utilizing preferential looking tasks to examine visual attention and recognition memory in infancy. The second section examines research utilizing neural measures of attention and object recognition in infancy as well as research on brain-behavior relations in the early development of attention and recognition memory. The third section addresses potential areas of the brain involved in infant object recognition and visual attention. An integrated synthesis of some of the existing models of the development of visual attention is presented which may account for the observed changes in behavioral and neural measures of visual attention and object recognition that occur across infancy. Copyright © 2015 Elsevier B.V. All rights reserved.

Glyph-Based Video Visualization for Semen Analysis

KAUST Repository

Duffy, Brian

2015-08-01

© 2013 IEEE. The existing efforts in computer assisted semen analysis have been focused on high speed imaging and automated image analysis of sperm motility. This results in a large amount of data, and it is extremely challenging for both clinical scientists and researchers to interpret, compare and correlate the multidimensional and time-varying measurements captured from video data. In this work, we use glyphs to encode a collection of numerical measurements taken at a regular interval and to summarize spatio-temporal motion characteristics using static visual representations. The design of the glyphs addresses the needs for (a) encoding some 20 variables using separable visual channels, (b) supporting scientific observation of the interrelationships between different measurements and comparison between different sperm cells and their flagella, and (c) facilitating the learning of the encoding scheme by making use of appropriate visual abstractions and metaphors. As a case study, we focus this work on video visualization for computer-aided semen analysis, which has a broad impact on both biological sciences and medical healthcare. We demonstrate that glyph-based visualization can serve as a means of external memorization of video data as well as an overview of a large set of spatiotemporal measurements. It enables domain scientists to make scientific observation in a cost-effective manner by reducing the burden of viewing videos repeatedly, while providing them with a new visual representation for conveying semen statistics.

VISUAL3D - An EIT network on visualization of geomodels

Science.gov (United States)

Bauer, Tobias

2017-04-01

When it comes to interpretation of data and understanding of deep geological structures and bodies at different scales then modelling tools and modelling experience is vital for deep exploration. Geomodelling provides a platform for integration of different types of data, including new kinds of information (e.g., new improved measuring methods). EIT Raw Materials, initiated by the EIT (European Institute of Innovation and Technology) and funded by the European Commission, is the largest and strongest consortium in the raw materials sector worldwide. The VISUAL3D network of infrastructure is an initiative by EIT Raw Materials and aims at bringing together partners with 3D-4D-visualisation infrastructure and 3D-4D-modelling experience. The recently formed network collaboration interlinks hardware, software and expert knowledge in modelling visualization and output. A special focus will be the linking of research, education and industry and integrating multi-disciplinary data and to visualize the data in three and four dimensions. By aiding network collaborations we aim at improving the combination of geomodels with differing file formats and data characteristics. This will create an increased competency in modelling visualization and the ability to interchange and communicate models more easily. By combining knowledge and experience in geomodelling with expertise in Virtual Reality visualization partners of EIT Raw Materials but also external parties will have the possibility to visualize, analyze and validate their geomodels in immersive VR-environments. The current network combines partners from universities, research institutes, geological surveys and industry with a strong background in geological 3D-modelling and 3D visualization and comprises: Luleå University of Technology, Geological Survey of Finland, Geological Survey of Denmark and Greenland, TUBA Freiberg, Uppsala University, Geological Survey of France, RWTH Aachen, DMT, KGHM Cuprum, Boliden, Montan

Visual function of cataract with high myopia

Directory of Open Access Journals (Sweden)

Jian-Tao Ren

2013-09-01

Full Text Available Cataract with high myopia is research priority associated with the large amount of high myopia patients. The unaided visual acuity and the best-corrected visual acuity are partial for the visual acuity of the patients with cataract. The mechanism and clinical significance of modern visual function measurements associated with cataract and high myopia, including accommodation and convergence, stereoscopic vision, contrast sensitivity, have been introduced. These measurements could be of great value in early diagnosis of cataract, assessment of surgical indication, customized intraocular lens(IOLselection and evaluation of visual performance after IOL implantation. They could also be helpful to the analysis of postoperative impaired visual function and its management. Having an adequate understanding of the contents and significance of visual function was helpful to the improvement of cataract surgery techniques and postoperative visual acuity.

Young children's coding and storage of visual and verbal material.

Science.gov (United States)

Perlmutter, M; Myers, N A

1975-03-01

36 preschool children (mean age 4.2 years) were each tested on 3 recognition memory lists differing in test mode (visual only, verbal only, combined visual-verbal). For one-third of the children, original list presentation was visual only, for another third, presentation was verbal only, and the final third received combined visual-verbal presentation. The subjects generally performed at a high level of correct responding. Verbal-only presentation resulted in less correct recognition than did either visual-only or combined visual-verbal presentation. However, because performances under both visual-only and combined visual-verbal presentation were statistically comparable, and a high level of spontaneous labeling was observed when items were presented only visually, a dual-processing conceptualization of memory in 4-year-olds was suggested.

Visually Evoked Visual-Auditory Changes Associated with Auditory Performance in Children with Cochlear Implants

Directory of Open Access Journals (Sweden)

Maojin Liang

2017-10-01

Full Text Available Activation of the auditory cortex by visual stimuli has been reported in deaf children. In cochlear implant (CI patients, a residual, more intense cortical activation in the frontotemporal areas in response to photo stimuli was found to be positively associated with poor auditory performance. Our study aimed to investigate the mechanism by which visual processing in CI users activates the auditory-associated cortex during the period after cochlear implantation as well as its relation to CI outcomes. Twenty prelingually deaf children with CI were recruited. Ten children were good CI performers (GCP and ten were poor (PCP. Ten age- and sex- matched normal-hearing children were recruited as controls, and visual evoked potentials (VEPs were recorded. The characteristics of the right frontotemporal N1 component were analyzed. In the prelingually deaf children, higher N1 amplitude was observed compared to normal controls. While the GCP group showed significant decreases in N1 amplitude, and source analysis showed the most significant decrease in brain activity was observed in the primary visual cortex (PVC, with a downward trend in the primary auditory cortex (PAC activity, but these did not occur in the PCP group. Meanwhile, higher PVC activation (comparing to controls before CI use (0M and a significant decrease in source energy after CI use were found to be related to good CI outcomes. In the GCP group, source energy decreased in the visual-auditory cortex with CI use. However, no significant cerebral hemispheric dominance was found. We supposed that intra- or cross-modal reorganization and higher PVC activation in prelingually deaf children may reflect a stronger potential ability of cortical plasticity. Brain activity evolution appears to be related to CI auditory outcomes.

Visually Evoked Visual-Auditory Changes Associated with Auditory Performance in Children with Cochlear Implants.

Science.gov (United States)

Liang, Maojin; Zhang, Junpeng; Liu, Jiahao; Chen, Yuebo; Cai, Yuexin; Wang, Xianjun; Wang, Junbo; Zhang, Xueyuan; Chen, Suijun; Li, Xianghui; Chen, Ling; Zheng, Yiqing

2017-01-01

Activation of the auditory cortex by visual stimuli has been reported in deaf children. In cochlear implant (CI) patients, a residual, more intense cortical activation in the frontotemporal areas in response to photo stimuli was found to be positively associated with poor auditory performance. Our study aimed to investigate the mechanism by which visual processing in CI users activates the auditory-associated cortex during the period after cochlear implantation as well as its relation to CI outcomes. Twenty prelingually deaf children with CI were recruited. Ten children were good CI performers (GCP) and ten were poor (PCP). Ten age- and sex- matched normal-hearing children were recruited as controls, and visual evoked potentials (VEPs) were recorded. The characteristics of the right frontotemporal N1 component were analyzed. In the prelingually deaf children, higher N1 amplitude was observed compared to normal controls. While the GCP group showed significant decreases in N1 amplitude, and source analysis showed the most significant decrease in brain activity was observed in the primary visual cortex (PVC), with a downward trend in the primary auditory cortex (PAC) activity, but these did not occur in the PCP group. Meanwhile, higher PVC activation (comparing to controls) before CI use (0M) and a significant decrease in source energy after CI use were found to be related to good CI outcomes. In the GCP group, source energy decreased in the visual-auditory cortex with CI use. However, no significant cerebral hemispheric dominance was found. We supposed that intra- or cross-modal reorganization and higher PVC activation in prelingually deaf children may reflect a stronger potential ability of cortical plasticity. Brain activity evolution appears to be related to CI auditory outcomes.

Neurophysiology of visual aura in migraine

International Nuclear Information System (INIS)

Shibata, Koichi

2007-01-01

Visual processing in migraine has been targeted because the visual symptoms that are commonly associated with attack, either in the form of aura or other more subtle symptoms, indicate that the visual pathways are involved in migrainous pathophysiology. The visual aura of the migraine attack has been explained by the cortical spreading depression (CSD) of Leao, neuroelectric event beginning in the occipital cortex and propagating into contiguous brain region. Clinical observations suggest that hyperexcitability occurs not only during the attack, typically in the form of photophobia, but also between attacks. Numerous human neuroimaging, neurophysiological and psychophysical studies have identified differences in cortical visual processing in migraine. The possibility of imaging the typical visual aura with BOLD functional MRI has revealed multiple neurovascular events in the occipital cortex within a single attack that closely resemble CSD. As transient synchronized neuronal excitation precedes CSD, changes in cortical excitability underlie the migraine attack. Independent evidence for altered neuronal excitability in migraineurs between attacks emerges from visual evoked potentials (VEPs) and transcranial magnetic stimulation (TMS), recordings of cortical potentials and psychophysics. Recently, both TMS and psychophysical studies measuring visual performance in migraineurs have used measures which presumably measure primary visual (V1) and visual association cortex. Our VEP and blink reflex study showed that migraine patients exhibiting allodynia might show central sensitization of braistem trigeminal neuron and had contrast modulation dysfunction during the cortical visual processing of V1 and visual association cortex in-between attacks. In pathophysiology of migraine, these neurophysiological and psychophysical studies indicate that abnormal visual and trigeminal hyperexcitability might persist between migraine attacks. The influence of migraine on cortical

Engineering visualization utilizing advanced animation

Science.gov (United States)

Sabionski, Gunter R.; Robinson, Thomas L., Jr.

1989-01-01

Engineering visualization is the use of computer graphics to depict engineering analysis and simulation in visual form from project planning through documentation. Graphics displays let engineers see data represented dynamically which permits the quick evaluation of results. The current state of graphics hardware and software generally allows the creation of two types of 3D graphics. The use of animated video as an engineering visualization tool is presented. The engineering, animation, and videography aspects of animated video production are each discussed. Specific issues include the integration of staffing expertise, hardware, software, and the various production processes. A detailed explanation of the animation process reveals the capabilities of this unique engineering visualization method. Automation of animation and video production processes are covered and future directions are proposed.

Astronomy, Visual Literacy, and Liberal Arts Education

Science.gov (United States)

Crider, Anthony

2016-01-01

With the exponentially growing amount of visual content that twenty-first century students will face throughout their lives, teaching them to respond to it with visual and information literacy skills should be a clear priority for liberal arts education. While visual literacy is more commonly covered within humanities curricula, I will argue that because astronomy is inherently a visual science, it is a fertile academic discipline for the teaching and learning of visual literacy. Astronomers, like many scientists, rely on three basic types of visuals to convey information: images, qualitative diagrams, and quantitative plots. In this talk, I will highlight classroom methods that can be used to teach students to "read" and "write" these three separate visuals. Examples of "reading" exercises include questioning the authorship and veracity of images, confronting the distorted scales of many diagrams published in astronomy textbooks, and extracting quantitative information from published plots. Examples of "writing" exercises include capturing astronomical images with smartphones, re-sketching textbook diagrams on whiteboards, and plotting data with Google Motion Charts or iPython notebooks. Students can be further pushed to synthesize these skills with end-of-semester slide presentations that incorporate relevant images, diagrams, and plots rather than relying solely on bulleted lists.

Frida Kahlo: Visual Articulations of Suffering and Loss.

Science.gov (United States)

Nixon, Lois LaCivita

1996-01-01

Illustrates the value of interdisciplinary approaches to patient care by exploring visual articulations of suffering as rendered by one artist. Makes general observations about the nature of humanities courses offered to medical students and depicts a visual portrayal of an illness story representing personal perspectives about patient suffering…

Scientific visualization uncertainty, multifield, biomedical, and scalable visualization

CERN Document Server

Chen, Min; Johnson, Christopher; Kaufman, Arie; Hagen, Hans

2014-01-01

Based on the seminar that took place in Dagstuhl, Germany in June 2011, this contributed volume studies the four important topics within the scientific visualization field: uncertainty visualization, multifield visualization, biomedical visualization and scalable visualization. • Uncertainty visualization deals with uncertain data from simulations or sampled data, uncertainty due to the mathematical processes operating on the data, and uncertainty in the visual representation, • Multifield visualization addresses the need to depict multiple data at individual locations and the combination of multiple datasets, • Biomedical is a vast field with select subtopics addressed from scanning methodologies to structural applications to biological applications, • Scalability in scientific visualization is critical as data grows and computational devices range from hand-held mobile devices to exascale computational platforms. Scientific Visualization will be useful to practitioners of scientific visualization, ...

A Dynamic Bayesian Observer Model Reveals Origins of Bias in Visual Path Integration.

Science.gov (United States)

Lakshminarasimhan, Kaushik J; Petsalis, Marina; Park, Hyeshin; DeAngelis, Gregory C; Pitkow, Xaq; Angelaki, Dora E

2018-06-20

Path integration is a strategy by which animals track their position by integrating their self-motion velocity. To identify the computational origins of bias in visual path integration, we asked human subjects to navigate in a virtual environment using optic flow and found that they generally traveled beyond the goal location. Such a behavior could stem from leaky integration of unbiased self-motion velocity estimates or from a prior expectation favoring slower speeds that causes velocity underestimation. Testing both alternatives using a probabilistic framework that maximizes expected reward, we found that subjects' biases were better explained by a slow-speed prior than imperfect integration. When subjects integrate paths over long periods, this framework intriguingly predicts a distance-dependent bias reversal due to buildup of uncertainty, which we also confirmed experimentally. These results suggest that visual path integration in noisy environments is limited largely by biases in processing optic flow rather than by leaky integration. Copyright © 2018 Elsevier Inc. All rights reserved.

DESAIN KOMUNIKASI VISUAL DAN PANGGILAN KRISTIANI

Directory of Open Access Journals (Sweden)

Herlianto

2003-01-01

Full Text Available Visual Communication Design is one of the arts movements. Being one aspect of the culture%2C it shows a holistic development and develops a great influence on human life including the way of thinking and attitude. To the Christian point of view%2C there are some visual media presentations that need special and precautious treatment. Abstract in Bahasa Indonesia : Disain Komunikasi Visual merupakan perkembangan yang makin maju dari seni sebagai aspek kebudayaan yang berkembang makin holistik dan punya daya pengaruh empat dimensional terhadap kehidupan manusia%2C yaitu pandangan dan pola perilaku dan kehidupan seseorang. Ditinjau dari Iman Kristiani%2C setidaknya ada berbagai bentuk pengaruh penyajian media visual yang perlu dihadapi dengan kewaspadaan. Visual Communication Design%2C Christian values.

First-person visualizations of the special and general theory of relativity

International Nuclear Information System (INIS)

Kraus, U

2008-01-01

Visualizations that adopt a first-person point of view allow observation and, in the case of interactive simulations, experimentation with relativistic scenes. This paper gives examples of three types of first-person visualizations: watching objects that move at nearly the speed of light, being a high-speed observer looking at a static environment and having a look-around near a compact object. I illustrate and explain the main aspects of the visual observations, outline their use in teaching relativity and report on teaching experiences. For teaching purposes, our visualization work is available on the website www.spacetimetravel.org and its German counterpart www.tempolimit-lichtgeschwindigkeit.de. This paper assumes some basic knowledge about relativity on the part of the reader. It addresses instructors of physics at the undergraduate and advanced secondary school level as well as their students

Communicating and visualizing data quality through Web Map Services

Science.gov (United States)

Roberts, Charles; Blower, Jon; Maso, Joan; Diaz, Daniel; Griffiths, Guy; Lewis, Jane

2014-05-01

The sharing and visualization of environmental data through OGC Web Map Services is becoming increasingly common. However, information about the quality of data is rarely presented. (In this presentation we consider mostly data uncertainty as a measure of quality, although we acknowledge that many other quality measures are relevant to the geoscience community.) In the context of the GeoViQua project (http://www.geoviqua.org) we have developed conventions and tools for using WMS to deliver data quality information. The "WMS-Q" convention describes how the WMS specification can be used to publish quality information at the level of datasets, variables and individual pixels (samples). WMS-Q requires no extensions to the WMS 1.3.0 specification, being entirely backward-compatible. (An earlier version of WMS-Q was published as OGC Engineering Report 12-160.) To complement the WMS-Q convention, we have also developed extensions to the OGC Symbology Encoding (SE) specification, enabling uncertain geoscience data to be portrayed using a variety of visualization techniques. These include contours, stippling, blackening, whitening, opacity, bivariate colour maps, confidence interval triangles and glyphs. There may also be more extensive applications of these methods beyond the visual representation of uncertainty. In this presentation we will briefly describe the scope of the WMS-Q and "extended SE" specifications and then demonstrate the innovations using open-source software based upon ncWMS (http://ncwms.sf.net). We apply the tools to a variety of datasets including Earth Observation data from the European Space Agency's Climate Change Initiative. The software allows uncertain raster data to be shared through Web Map Services, giving the user fine control over data visualization.

Impacts of soil moisture content on visual soil evaluation

Science.gov (United States)

Emmet-Booth, Jeremy; Forristal, Dermot; Fenton, Owen; Bondi, Giulia; Creamer, Rachel; Holden, Nick

2017-04-01

Visual Soil Examination and Evaluation (VSE) techniques offer tools for soil quality assessment. They involve the visual and tactile assessment of soil properties such as aggregate size and shape, porosity, redox morphology, soil colour and smell. An increasing body of research has demonstrated the reliability and utility of VSE techniques. However a number of limitations have been identified, including the potential impact of soil moisture variation during sampling. As part of a national survey of grassland soil quality in Ireland, an evaluation of the impact of soil moisture on two widely used VSE techniques was conducted. The techniques were Visual Evaluation of Soil Structure (VESS) (Guimarães et al., 2011) and Visual Soil Assessment (VSA) (Shepherd, 2009). Both generate summarising numeric scores that indicate soil structural quality, though employ different scoring mechanisms. The former requires the assessment of properties concurrently and the latter separately. Both methods were deployed on 20 sites across Ireland representing a range of soils. Additional samples were taken for soil volumetric water (θ) determination at 5-10 and 10-20 cm depth. No significant correlation was observed between θ 5-10 cm and either VSE technique. However, VESS scores were significantly related to θ 10-20 cm (rs = 0.40, sig = 0.02) while VSA scores were not (rs = -0.33, sig = 0.06). VESS and VSA scores can be grouped into quality classifications (good, moderate and poor). No significant mean difference was observed between θ 5-10 cm or θ 10-20 cm according to quality classification by either method. It was concluded that VESS scores may be affected by soil moisture variation while VSA appear unaffected. The different scoring mechanisms, where the separate assessment and scoring of individual properties employed by VSA, may limit soil moisture effects. However, moisture content appears not to affect overall structural quality classification by either method. References

Non-Destructive Approaches for the Validation of Visually Observed Spatial Patterns of Decay

Science.gov (United States)

Johnston, Brian; McKinley, Jennifer; Warke, Patricia; Ruffell, Alastair

2017-04-01

Historical structures are regarded as a built legacy that is passed down through the generations and as such the conservation and restoration of these buildings is of great importance to governmental, religious and charitable organisations. As these groups play the role of custodians of this built heritage, they are therefore keen that the approaches employed in these studies of stone condition are non-destructive in nature. Determining sections of facades requiring repair work is often achieved through a visual conditional inspection of the stonework by a specialist. However, these reports focus upon the need to identify blocks requiring restorative action rather than the determination of spatial trends that lead to the identification of causes. This fixation on decay occurring at the block scale results in the spatial distribution of weathering present at the larger 'wall' scale appearing to have developed chaotically. Recent work has shown the importance of adopting a geomorphological focus when undertaking visual inspection of the facades of historical buildings to overcome this issue. Once trends have been ascertained, they can be used to bolster remedial strategies that target the sources of decay rather than just undertaking an aesthetic treatment of symptoms. Visual inspection of the study site, Fitzroy Presbyterian Church in Belfast, using the geomorphologically driven approach revealed three features suggestive of decay extending beyond the block scale. Firstly, the influence of architectural features on the susceptibility of blocks to decay. Secondly, the impact of the fluctuation in groundwater rise over the seasons and the influence of aspect upon this process. And finally, the interconnectivity of blocks, due to deteriorating mortar and poor repointing, providing conduits for the passage of moisture. Once these patterns were identified, it has proven necessary to validate the outcome of the visual inspection using other techniques. In this study

Modeling the effect of selection history on pop-out visual search.

Directory of Open Access Journals (Sweden)

Yuan-Chi Tseng

Full Text Available While attentional effects in visual selection tasks have traditionally been assigned "top-down" or "bottom-up" origins, more recently it has been proposed that there are three major factors affecting visual selection: (1 physical salience, (2 current goals and (3 selection history. Here, we look further into selection history by investigating Priming of Pop-out (POP and the Distractor Preview Effect (DPE, two inter-trial effects that demonstrate the influence of recent history on visual search performance. Using the Ratcliff diffusion model, we model observed saccadic selections from an oddball search experiment that included a mix of both POP and DPE conditions. We find that the Ratcliff diffusion model can effectively model the manner in which selection history affects current attentional control in visual inter-trial effects. The model evidence shows that bias regarding the current trial's most likely target color is the most critical parameter underlying the effect of selection history. Our results are consistent with the view that the 3-item color-oddball task used for POP and DPE experiments is best understood as an attentional decision making task.

Stroke survivors' views and experiences on impact of visual impairment.

Science.gov (United States)

Rowe, Fiona J

2017-09-01

We sought to determine stroke survivors' views on impact of stroke-related visual impairment to quality of life. Stroke survivors with visual impairment, more than 1 year post stroke onset, were recruited. Semistructured biographical narrative interviews were audio-recorded and transcribed verbatim. A thematic approach to analysis of the qualitative data was adopted. Transcripts were systematically coded using NVivo10 software. Thirty-five stroke survivors were interviewed across the UK: 16 females, 19 males; aged 20-75 years at stroke onset. Five qualitative themes emerged: "Formal care," "Symptoms and self," "Adaptations," "Daily life," and "Information." Where visual problems existed, they were often not immediately recognized as part of the stroke syndrome and attributed to other causes such as migraine. Many participants did not receive early vision assessment or treatment for their visual problems. Visual problems included visual field loss, double vision, and perceptual problems. Impact of visual problems included loss in confidence, being a burden to others, increased collisions/accidents, and fear of falling. They made many self-identified adaptations to compensate for visual problems: magnifiers, large print, increased lighting, use of white sticks. There was a consistent lack of support and provision of information about visual problems. Poststroke visual impairment causes considerable impact to daily life which could be substantially improved by simple measures including early formal visual assessment, management and advice on adaptive strategies and self-management options. Improved education about poststroke visual impairment for the public and clinicians could aid earlier diagnosis of visual impairments.

Teacher-Made Tactile Science Materials with Critical and Creative Thinking Activities for Learners Including Those with Visual Impairments

Science.gov (United States)

Teske, Jolene K.; Gray, Phyllis; Kuhn, Mason A.; Clausen, Courtney K.; Smith, Latisha L.; Alsubia, Sukainah A.; Ghayoorad, Maryam; Rule, Audrey C.; Schneider, Jean Suchsland

2014-01-01

Gifted students with visual impairments are twice exceptional learners and may not evidence their advanced science aptitudes without appropriate accommodations for learning science. However, effective tactile science teaching materials may be easily made. Recent research has shown that when tactile materials are used with "all" students…

Visual dot interaction with short-term memory.

Science.gov (United States)

Etindele Sosso, Faustin Armel

2017-06-01

Many neurodegenerative diseases have a memory component. Brain structures related to memory are affected by environmental stimuli, and it is difficult to dissociate effects of all behavior of neurons. Here, visual cortex of mice was stimulated with gratings and dot, and an observation of neuronal activity before and after was made. Bandwidth, firing rate and orientation selectivity index were evaluated. A primary communication between primary visual cortex and short-term memory appeared to show an interesting path to train cognitive circuitry and investigate the basics mechanisms of the neuronal learning. The findings also suggested the interplay between primary visual cortex and short-term plasticity. The properties inside a visual target shape the perception and affect the basic encoding. Using visual cortex, it may be possible to train the memory and improve the recovery of people with cognitive disabilities or memory deficit.

Visualizing Structure and Dynamics of Disaccharide Simulations

Energy Technology Data Exchange (ETDEWEB)

Matthews, J. F.; Beckham, G. T.; Himmel, M. E.; Crowley, M. F.

2012-01-01

We examine the effect of several solvent models on the conformational properties and dynamics of disaccharides such as cellobiose and lactose. Significant variation in timescale for large scale conformational transformations are observed. Molecular dynamics simulation provides enough detail to enable insight through visualization of multidimensional data sets. We present a new way to visualize conformational space for disaccharides with Ramachandran plots.

Classifying web pages with visual features

NARCIS (Netherlands)

de Boer, V.; van Someren, M.; Lupascu, T.; Filipe, J.; Cordeiro, J.

2010-01-01

To automatically classify and process web pages, current systems use the textual content of those pages, including both the displayed content and the underlying (HTML) code. However, a very important feature of a web page is its visual appearance. In this paper, we show that using generic visual

Visualization of graphical information fusion results

Science.gov (United States)

Blasch, Erik; Levchuk, Georgiy; Staskevich, Gennady; Burke, Dustin; Aved, Alex

2014-06-01

Graphical fusion methods are popular to describe distributed sensor applications such as target tracking and pattern recognition. Additional graphical methods include network analysis for social, communications, and sensor management. With the growing availability of various data modalities, graphical fusion methods are widely used to combine data from multiple sensors and modalities. To better understand the usefulness of graph fusion approaches, we address visualization to increase user comprehension of multi-modal data. The paper demonstrates a use case that combines graphs from text reports and target tracks to associate events and activities of interest visualization for testing Measures of Performance (MOP) and Measures of Effectiveness (MOE). The analysis includes the presentation of the separate graphs and then graph-fusion visualization for linking network graphs for tracking and classification.

Experiment and analysis of basic phenomena of gas catching by liquid surface. Observation by visualizing vortex structure and gas catching process

International Nuclear Information System (INIS)

Kamemoto, Takashi; Nishiyama, Tadao

1995-01-01

Since gravity, viscous force, surface tension and so on are related simultaneously to the inertia force of flow, in gas catching phenomena, it is often difficult to grasp exactly its similarity. At the time of designing actual equipment, careful model test is required, and the validity of the evaluation by model test for applying it to actual machines sometimes becomes a problem. In this research, for the purpose of elucidating the essential mechanism of the gas-catching phenomena by vortices, and obtaining the knowledge useful for the probability of the method of evaluating the limit of gas catching, the knowledge obtained so far on the similarity law and model testing method related to the air catching by vortices was put in order, and vortex structure and basic gas-catching process were observed by water flow visualizing experiment, thus the noteworthy flow characteristics for clarifying the essential mechanism of the phenomena were obtained. The main knowledges on the air catching by vortices obtained so far, the experiment of visualizing vortices using water flow and the experimental results are reported. (K.I.)

Visual Biofeedback using trans-perineal ultrasound during the second stage of labor.

Science.gov (United States)

Gilboa, Yinon; Frenkel, Tahl I; Schlesinger, Yael; Rousseau, Sofie; Hamiel, Daniel; Achiron, Reuven; Perlman, Sharon

2017-11-20

to assess the obstetrical and psychological effect of visual biofeedback using trans-perineal ultrasound (TPU) during the second stage of labor. Visual biofeedback using TPU was performed prospectively during the second stage of labor in twenty-six low risk nulliparous women. Pushing efficacy was assessed by the angle of progression at rest and during pushing efforts before and after observing the ultrasound screen. Obstetrical outcomes included level of perineal tearing, mode of delivery and length of the second stage. Psychological outcomes were assessed via self-report measures during the postnatal hospital stay. These included measures of perceived control and maternal satisfaction with childbirth as well as level of maternal feelings of connectedness toward her newborn. Obstetrical and psychological results were compared to a control group (n=69) who received standard obstetrical coaching by midwifes. Pushing efficacy significantly increased following visual biofeedback by TPU (p = 0.01). A significant association was found between the visual biofeedback and an intact perineum following delivery (p = 0.03). No significant differences were found in regard to mode of delivery or the length of the second stage. Feelings of maternal connectedness towards the newborn were significantly higher in the visual biofeedback group relative to non-biofeedback controls (p = 0.003). The results of this pilot study implicate that TPU may serve as a complementary tool to coached maternal pushing during the second stage of labor with obstetrical as well as psychological benefits. Further studies are required to confirm our findings and define the exact timing for optimal results. This article is protected by copyright. All rights reserved.

Static Balance of Visually Impaired Athletes in Open and Closed Skill Sports

Directory of Open Access Journals (Sweden)

Bednarczuk Grzegorz

2017-03-01

Full Text Available Introduction. In elite sport, athletes are required to maintain appropriate body posture control despite a number of destabilising factors. The functions of body posture control are monitored by the central nervous system that constantly receives information from the vestibular and somatosensory systems as well as from the visual analyser. Visual impairment may contribute to a decrease in the level of motor abilities and skills; however, it does not prevent visually impaired individuals from taking up physical activity. Therefore, this study sought to assess the static balance of visually impaired goalball players and shooters. Material and methods. The study included 37 goalball players and 20 shooters. A force platform was used to assess static balance. The study participants performed tests: standing on both feet with eyes open (BFEO and closed (BFEC (30 s, single left- and right-leg stance with eyes open (SLEO and SREO as well as single left- and right-leg stance with eyes closed (SLEC and SREC. Statistical analyses were carried out using the following parameters: centre of pressure (CoP path length [cm], CoP velocity [m/s], and the surface area of the stabilogram [cm2]. Results. No significant differences were found between goalball players and shooters in static balance levels. However, such differences were observed after taking into account the number of athletes who were capable of performing particular tests. Conclusions. The findings indirectly confirm that there is a correlation between the type of physical activity and balance levels in visually impaired individuals. Further research ought to include tests performed on an unstable surface.

Measuring Visual Double Stars with Robotic Telescopes

Science.gov (United States)

Boyce, Pat; Boyce, Grady; Genet, Russell M.; Faisal Al-Zaben, Dewei Li, Yongyao Li, Aren Dennis, Zhixin Cao, Junyao Li, Steven Qu, Jeff Li, Michael Fene, Allen Priest, Stephen Priest, Rex Qiu, , and, Bill Riley

2016-06-01

The Astronomy Research Seminars introduce students to scientific research by carrying out the entire process: planning a scientific research project, writing a research proposal, gathering and analyzing observational data, drawing conclusions, and presenting the research results in a published paper and presentation.In 2015 Cuesta College and Russell Genet sponsored a new hybrid format for the seminar enabling distance learning. Boyce Research Initiatives and Education Foundation (BRIEF) conducted the course at The Army and Navy Academy (ANA) in Carlsbad, California, in the spring and fall of 2015.The course objective is to complete the research and publish the paper within one semester. Our program schedule called for observations to be performed within a two week period. Measurement of visual binary stars was chosen because sufficient observations could be made in just two evenings of good weather. We quickly learned that our location by the ocean did not provide reliable weather to use local telescopes.The iTelescope network of robotic telescopes located in Australia, Spain and the U.S. solved the problem. Reservations for these systems are booked online and include date, time, exposure and filters. The high quality telescopes range from 4" to 27" in size with excellent cameras. By watching the weather forecasts for the sites, we were able to schedule our observations within the two week time frame required.Timely and reliable data reduction was the next hurdle. The students were using widely varying equipment (PCs, MACs, tablets, smart phones) with incompatible software. After wasting time trying to be computer technicians, we settled a on standard set of software relying on Mirametrics' Mira Pro x64. We installed the software on an old laptop, downloaded the iTelescope data files, gave the students remote access using GoToMyPC.These efficiencies enabled us to meet the demanding one semester schedule and assure a better learning experience. We have been able to

1st Workshop on Eye Tracking and Visualization

CERN Document Server

Chuang, Lewis; Fisher, Brian; Schmidt, Albrecht; Weiskopf, Daniel

2017-01-01

This book discusses research, methods, and recent developments in the interdisciplinary field that spans research in visualization, eye tracking, human-computer interaction, and psychology. It presents extended versions of papers from the First Workshop on Eye Tracking and Visualization (ETVIS), which was organized as a workshop of the IEEE VIS Conference 2015. Topics include visualization and visual analytics of eye-tracking data, metrics and cognitive models, eye-tracking experiments in the context of visualization interfaces, and eye tracking in 3D and immersive environments. The extended ETVIS papers are complemented by a chapter offering an overview of visualization approaches for analyzing eye-tracking data and a chapter that discusses electrooculography (EOG) as an alternative of acquiring information about eye movements. Covering scientific visualization, information visualization, and visual analytics, this book is a valuable resource for eye-tracking researchers within the visualization community.

Attention and visual memory in visualization and computer graphics.

Science.gov (United States)

Healey, Christopher G; Enns, James T

2012-07-01

A fundamental goal of visualization is to produce images of data that support visual analysis, exploration, and discovery of novel insights. An important consideration during visualization design is the role of human visual perception. How we "see" details in an image can directly impact a viewer's efficiency and effectiveness. This paper surveys research on attention and visual perception, with a specific focus on results that have direct relevance to visualization and visual analytics. We discuss theories of low-level visual perception, then show how these findings form a foundation for more recent work on visual memory and visual attention. We conclude with a brief overview of how knowledge of visual attention and visual memory is being applied in visualization and graphics. We also discuss how challenges in visualization are motivating research in psychophysics.

A Brief Period of Postnatal Visual Deprivation Alters the Balance between Auditory and Visual Attention.

Science.gov (United States)

de Heering, Adélaïde; Dormal, Giulia; Pelland, Maxime; Lewis, Terri; Maurer, Daphne; Collignon, Olivier

2016-11-21

Is a short and transient period of visual deprivation early in life sufficient to induce lifelong changes in how we attend to, and integrate, simple visual and auditory information [1, 2]? This question is of crucial importance given the recent demonstration in both animals and humans that a period of blindness early in life permanently affects the brain networks dedicated to visual, auditory, and multisensory processing [1-16]. To address this issue, we compared a group of adults who had been treated for congenital bilateral cataracts during early infancy with a group of normally sighted controls on a task requiring simple detection of lateralized visual and auditory targets, presented alone or in combination. Redundancy gains obtained from the audiovisual conditions were similar between groups and surpassed the reaction time distribution predicted by Miller's race model. However, in comparison to controls, cataract-reversal patients were faster at processing simple auditory targets and showed differences in how they shifted attention across modalities. Specifically, they were faster at switching attention from visual to auditory inputs than in the reverse situation, while an opposite pattern was observed for controls. Overall, these results reveal that the absence of visual input during the first months of life does not prevent the development of audiovisual integration but enhances the salience of simple auditory inputs, leading to a different crossmodal distribution of attentional resources between auditory and visual stimuli. Copyright © 2016 Elsevier Ltd. All rights reserved.

Species identification and other data collected from visual observation and other data from AIRCRAFT in the Puget Sound from 23 May 1978 to 31 October 1978 (NODC Accession 7900174)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Species identification and other data were collected using visual observation and other instruments from AIRCRAFT in the Puget Sound. Data were collected from 23 May...

Individual animals and other data collected using visual observations and other instruments from AIRCRAFT in the Arctic Ocean from 02 August 1979 to 18 October 1982 (NODC Accession 8400149)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Individual animals and other data were collected using visual observations and other instruments in the Arctic Ocean by AIRCRAFT. Data were collected from 02 August...

Pareidolias: complex visual illusions in dementia with Lewy bodies.

Science.gov (United States)

Uchiyama, Makoto; Nishio, Yoshiyuki; Yokoi, Kayoko; Hirayama, Kazumi; Imamura, Toru; Shimomura, Tatsuo; Mori, Etsuro

2012-08-01

Patients rarely experience visual hallucinations while being observed by clinicians. Therefore, instruments to detect visual hallucinations directly from patients are needed. Pareidolias, which are complex visual illusions involving ambiguous forms that are perceived as meaningful objects, are analogous to visual hallucinations and have the potential to be a surrogate indicator of visual hallucinations. In this study, we explored the clinical utility of a newly developed instrument for evoking pareidolic illusions, the Pareidolia test, in patients with dementia with Lewy bodies-one of the most common causes of visual hallucinations in the elderly. Thirty-four patients with dementia with Lewy bodies, 34 patients with Alzheimer's disease and 26 healthy controls were given the Pareidolia test. Patients with dementia with Lewy bodies produced a much greater number of pareidolic illusions compared with those with Alzheimer's disease or controls. A receiver operating characteristic analysis demonstrated that the number of pareidolias differentiated dementia with Lewy bodies from Alzheimer's disease with a sensitivity of 100% and a specificity of 88%. Full-length figures and faces of people and animals accounted for >80% of the contents of pareidolias. Pareidolias were observed in patients with dementia with Lewy bodies who had visual hallucinations as well as those who did not have visual hallucinations, suggesting that pareidolias do not reflect visual hallucinations themselves but may reflect susceptibility to visual hallucinations. A sub-analysis of patients with dementia with Lewy bodies who were or were not treated with donepzil demonstrated that the numbers of pareidolias were correlated with visuoperceptual abilities in the former and with indices of hallucinations and delusional misidentifications in the latter. Arousal and attentional deficits mediated by abnormal cholinergic mechanisms and visuoperceptual dysfunctions are likely to contribute to the development

Visions of our Planet's Atmosphere, Land and Oceans: Spectacular Visualizations of our Blue Marble

Science.gov (United States)

Hasler, A. F.; Starr, David (Technical Monitor)

2002-01-01

The NASA/NOAA Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to South Africa, Cape Town and Johannesburg using NASA Terra/MODIS data, Landsat data and 1 m IKONOS 'Spy Satellite' data. Zoom in to any place South Africa using Earth Viewer 3D from Keyhole Inc. and Landsat data at 30 m resolution. Go back to the early weather satellite images from the 1960s and see them contrasted with the latest US and international global satellite weather movies including hurricanes and 'tornadoes'. See the latest visualizations of spectacular images from NASA/NOAA remote sensing missions like Terra, GOES, TRMM, SeaWiFS, Landsat 7 including 1 - min GOES rapid scan image sequences of Nov 9th 2001 Midwest tornadic thunderstorms and have them explained.

Study Of Visual Disorders In Egyptian Computer Operators

International Nuclear Information System (INIS)

Al-Awadi, M.Y.; Awad Allah, H.; Hegazy, M. T.; Naguib, N.; Akmal, M.

2012-01-01

The aim of the study was to evaluate the probable effects of exposure to electromagnetic waves radiated from visual display terminals on some of visual functions. 300 computer operators working in different institutes were selected randomly. They were asked to fill a pre-tested questionnaire (written in Arabic) after obtaining their verbal consent. Among them, one hundred fifty exposed to visual display terminals were selected for the clinical study (group I). The control group includes one hundred fifty participants (their age matched with group I) but working in a field that did not expose to visual display terminals (group II). All chosen individuals were not suffering from any apparent health problems or any apparent diseases that could affect their visual conditions. All exposed candidates were using a VDT of LCD type size 15 and 17 and larger. Data entry and analysis were done using the SPSS version 17.0 applying appropriate statistical methods. The results showed that among the 150 exposed studied subjects, high significant occurrence of dryness and high significant association between occurrence of asthenopia and background variables (working hours using computers) were observed. Exposed subjects showed that 92% complained of tired eyes and eye strain, 37.33% complained of dry or sore eyes, 68% complained of headache, 68% complained of blurred distant vision 45.33% complained of asthenopia and 89.33% complained of neck, shoulder and back aches. Meantime, the control group showed that 18% complained of tired eyes, 21.33% of dry eyes and 12.67% of neck, shoulder and back aches. It could be concluded that prevalence of computer vision syndrome was noted to be quite high among computer operators.

Audiovisual correspondence between musical timbre and visual shapes.

Directory of Open Access Journals (Sweden)

Mohammad eAdeli

2014-05-01

Full Text Available This article investigates the cross-modal correspondences between musical timbre and shapes. Previously, such features as pitch, loudness, light intensity, visual size, and color characteristics have mostly been used in studies of audio-visual correspondences. Moreover, in most studies, simple stimuli e.g. simple tones have been utilized. In this experiment, 23 musical sounds varying in fundamental frequency and timbre but fixed in loudness were used. Each sound was presented once against colored shapes and once against grayscale shapes. Subjects had to select the visual equivalent of a given sound i.e. its shape, color (or grayscale and vertical position. This scenario permitted studying the associations between normalized timbre and visual shapes as well as some of the previous findings for more complex stimuli. 119 subjects (31 females and 88 males participated in the online experiment. Subjects included 36 claimed professional musicians, 47 claimed amateur musicians and 36 claimed non-musicians. 31 subjects have also claimed to have synesthesia-like experiences. A strong association between timbre of envelope normalized sounds and visual shapes was observed. Subjects have strongly associated soft timbres with blue, green or light gray rounded shapes, harsh timbres with red, yellow or dark gray sharp angular shapes and timbres having elements of softness and harshness together with a mixture of the two previous shapes. Color or grayscale had no effect on timbre-shape associations. Fundamental frequency was not associated with height, grayscale or color. The significant correspondence between timbre and shape revealed by the present work allows designing substitution systems which might help the blind to perceive shapes through timbre.

[Functional results of cryosurgical procedures in rhegmatogenous retinal detachment including macula region - our experience].

Science.gov (United States)

Chrapek, O; Sín, M; Jirková, B; Jarkovský, J; Rehák, J

2013-10-01

Aim of this study is to evaluate retrospectively functional results of cryosurgical treatment of uncomplicated, idiopathic rhegmatogenous retinal detachment including macula region in phakic patients operated on at the Department of Ophthalmology, Faculty Hospital, Palacký University, Olomouc, Czech Republic, E.U., during the period 2002 -2013, and to evaluate the significance of the macula detachment duration for the final visual acuity. In the study group were included 56 eyes of 56 patients operated in the years 2003 - 2012 at the Department of Ophthalmology, Faculty Hospital, Palacký University, Olomouc. All patients were phakic and in all of them, the retinal detachment including the macula region was diagnosed. The mean follow-up period of the patients was 8,75 months. The initial and final visual acuity testing were performed. Comparing the initial and final visual acuity we rated the level of the visual acuity change. The result was stated as improved, if the visual acuity improved by 1 or more lines on the ETDRS chart. The result was rated as stabilized, if the visual acuity remained the same or it changed by 1 line of the ETDRS chart only. The result was evaluated as worsened, if the visual acuity decreased by 1 or more lines of the ETDRS chart. In the followed-up group, the authors compared visual acuity levels in patients with the macula detachment duration 10 days and 11 days. For the statistical evaluation of achieved results, the Mann - Whitney U test was used. The visual acuity improved in 49 (87 %), did not changed in 5 (9 %) and worsened in 2 (4 %) patients. The patients with macula detachment duration 10 days achieved statistically significant better visual acuity than patients with macula detachment duration 11 days. Patients with macula detachment duration 10 days have better prognosis for functional result than patients with macula detachment duration 11 days.

Visual-Spatial Attention Aids the Maintenance of Object Representations in Visual Working Memory

Science.gov (United States)

Williams, Melonie; Pouget, Pierre; Boucher, Leanne; Woodman, Geoffrey F.

2013-01-01

Theories have proposed that the maintenance of object representations in visual working memory is aided by a spatial rehearsal mechanism. In this study, we used two different approaches to test the hypothesis that overt and covert visual-spatial attention mechanisms contribute to the maintenance of object representations in visual working memory. First, we tracked observers’ eye movements while remembering a variable number of objects during change-detection tasks. We observed that during the blank retention interval, participants spontaneously shifted gaze to the locations that the objects had occupied in the memory array. Next, we hypothesized that if attention mechanisms contribute to the maintenance of object representations, then drawing attention away from the object locations during the retention interval would impair object memory during these change-detection tasks. Supporting this prediction, we found that attending to the fixation point in anticipation of a brief probe stimulus during the retention interval reduced change-detection accuracy even on the trials in which no probe occurred. These findings support models of working memory in which visual-spatial selection mechanisms contribute to the maintenance of object representations. PMID:23371773

Enhanced alpha-oscillations in visual cortex during anticipation of self-generated visual stimulation.

Science.gov (United States)

Stenner, Max-Philipp; Bauer, Markus; Haggard, Patrick; Heinze, Hans-Jochen; Dolan, Ray

2014-11-01

The perceived intensity of sensory stimuli is reduced when these stimuli are caused by the observer's actions. This phenomenon is traditionally explained by forward models of sensory action-outcome, which arise from motor processing. Although these forward models critically predict anticipatory modulation of sensory neural processing, neurophysiological evidence for anticipatory modulation is sparse and has not been linked to perceptual data showing sensory attenuation. By combining a psychophysical task involving contrast discrimination with source-level time-frequency analysis of MEG data, we demonstrate that the amplitude of alpha-oscillations in visual cortex is enhanced before the onset of a visual stimulus when the identity and onset of the stimulus are controlled by participants' motor actions. Critically, this prestimulus enhancement of alpha-amplitude is paralleled by psychophysical judgments of a reduced contrast for this stimulus. We suggest that alpha-oscillations in visual cortex preceding self-generated visual stimulation are a likely neurophysiological signature of motor-induced sensory anticipation and mediate sensory attenuation. We discuss our results in relation to proposals that attribute generic inhibitory functions to alpha-oscillations in prioritizing and gating sensory information via top-down control.

The picture superiority effect in categorization: visual or semantic?

Science.gov (United States)

Job, R; Rumiati, R; Lotto, L

1992-09-01

Two experiments are reported whose aim was to replicate and generalize the results presented by Snodgrass and McCullough (1986) on the effect of visual similarity in the categorization process. For pictures, Snodgrass and McCullough's results were replicated because Ss took longer to discriminate elements from 2 categories when they were visually similar than when they were visually dissimilar. However, unlike Snodgrass and McCullough, an analogous increase was also observed for word stimuli. The pattern of results obtained here can be explained most parsimoniously with reference to the effect of semantic similarity, or semantic and visual relatedness, rather than to visual similarity alone.

Visualizing guided tours

DEFF Research Database (Denmark)

Poulsen, Signe Herbers; Fjord-Larsen, Mads; Hansen, Frank Allan

This paper identifies several problems with navigating and visualizing guided tours in traditional hypermedia systems. We discuss solutions to these problems, including the representation of guided tours as 3D metro maps with content preview. Issues regarding navigation and disorientation...

How accurate are interpretations of curriculum-based measurement progress monitoring data? Visual analysis versus decision rules.

Science.gov (United States)

Van Norman, Ethan R; Christ, Theodore J

2016-10-01

Curriculum based measurement of oral reading (CBM-R) is used to monitor the effects of academic interventions for individual students. Decisions to continue, modify, or terminate these interventions are made by interpreting time series CBM-R data. Such interpretation is founded upon visual analysis or the application of decision rules. The purpose of this study was to compare the accuracy of visual analysis and decision rules. Visual analysts interpreted 108 CBM-R progress monitoring graphs one of three ways: (a) without graphic aids, (b) with a goal line, or (c) with a goal line and a trend line. Graphs differed along three dimensions, including trend magnitude, variability of observations, and duration of data collection. Automated trend line and data point decision rules were also applied to each graph. Inferential analyses permitted the estimation of the probability of a correct decision (i.e., the student is improving - continue the intervention, or the student is not improving - discontinue the intervention) for each evaluation method as a function of trend magnitude, variability of observations, and duration of data collection. All evaluation methods performed better when students made adequate progress. Visual analysis and decision rules performed similarly when observations were less variable. Results suggest that educators should collect data for more than six weeks, take steps to control measurement error, and visually analyze graphs when data are variable. Implications for practice and research are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Visual Literacy and Visual Culture.

Science.gov (United States)

Messaris, Paul

Familiarity with specific images or sets of images plays a role in a culture's visual heritage. Two questions can be asked about this type of visual literacy: Is this a type of knowledge that is worth building into the formal educational curriculum of our schools? What are the educational implications of visual literacy? There is a three-part…

Laminar pattern of cholinergic and adrenergic receptors in rat visual cortex using quantitative receptor autoradiography

International Nuclear Information System (INIS)

Schliebs, R.; Walch, C.

1989-01-01

The laminar distribution of muscarinic acetylcholine receptors, including the M1-receptor subtype, of beta-adrenergic receptors, and noradrenaline uptake sites, was studied in the adult rat visual, frontal, somatosensory and motor cortex, using quantitative receptor autoradiography. In the visual cortex, the highest density of muscarinic acetylcholine receptors was found in layer I. From layer II/III to layer V binding decreases continueously reaching a constant binding level in layers V and VI. This laminar pattern of muscarinic receptor density differs somewhat from that observed in the non-visual cortical regions examined: layer II/III contained the highest receptor density followed by layer I and IV: lowest density was found in layer V and VI. The binding profile of the muscarinic cholinergic M1-subtype through the visual cortex shows a peak in cortical layer II and in the upper part of layer VI, whereas in the non-visual cortical regions cited the binding level was high in layer II/III, moderate in layer I and IV, and low in layer VI. Layers I to IV of the visual cortex contained the highest beta-adrenergic receptor densities, whereas only low binding levels were observed in the deeper layers. A similar laminar distribution was found also in the frontal, somatosensory and motor cortex. The density of noradrenaline uptake sites was high in all layers of the cortical regions studied, but with noradrenaline uptake sites somewhat more concentrated in the superficial layers than in deeper ones. The distinct laminar pattern of cholinergic and noradrenergic receptor sites indicates a different role for acetylcholine and noradrenaline in the functional anatomy of the cerebral cortex, and in particular, the visual cortex. (author)

Laminar pattern of cholinergic and adrenergic receptors in rat visual cortex using quantitative receptor autoradiography

Energy Technology Data Exchange (ETDEWEB)

Schliebs, R; Walch, C [Leipzig Univ. (German Democratic Republic). Bereich Medizin; Stewart, M G [Open Univ., Milton Keynes (UK)

1989-01-01

The laminar distribution of muscarinic acetylcholine receptors, including the M1-receptor subtype, of beta-adrenergic receptors, and noradrenaline uptake sites, was studied in the adult rat visual, frontal, somatosensory and motor cortex, using quantitative receptor autoradiography. In the visual cortex, the highest density of muscarinic acetylcholine receptors was found in layer I. From layer II/III to layer V binding decreases continueously reaching a constant binding level in layers V and VI. This laminar pattern of muscarinic receptor density differs somewhat from that observed in the non-visual cortical regions examined: layer II/III contained the highest receptor density followed by layer I and IV: lowest density was found in layer V and VI. The binding profile of the muscarinic cholinergic M1-subtype through the visual cortex shows a peak in cortical layer II and in the upper part of layer VI, whereas in the non-visual cortical regions cited the binding level was high in layer II/III, moderate in layer I and IV, and low in layer VI. Layers I to IV of the visual cortex contained the highest beta-adrenergic receptor densities, whereas only low binding levels were observed in the deeper layers. A similar laminar distribution was found also in the frontal, somatosensory and motor cortex. The density of noradrenaline uptake sites was high in all layers of the cortical regions studied, but with noradrenaline uptake sites somewhat more concentrated in the superficial layers than in deeper ones. The distinct laminar pattern of cholinergic and noradrenergic receptor sites indicates a different role for acetylcholine and noradrenaline in the functional anatomy of the cerebral cortex, and in particular, the visual cortex. (author).

Interactive data visualization foundations, techniques, and applications

CERN Document Server

Ward, Matthew; Keim, Daniel

2010-01-01

Visualization is the process of representing data, information, and knowledge in a visual form to support the tasks of exploration, confirmation, presentation, and understanding. This book is designed as a textbook for students, researchers, analysts, professionals, and designers of visualization techniques, tools, and systems. It covers the full spectrum of the field, including mathematical and analytical aspects, ranging from its foundations to human visual perception; from coded algorithms for different types of data, information and tasks to the design and evaluation of new visualization techniques. Sample programs are provided as starting points for building one's own visualization tools. Numerous data sets have been made available that highlight different application areas and allow readers to evaluate the strengths and weaknesses of different visualization methods. Exercises, programming projects, and related readings are given for each chapter. The book concludes with an examination of several existin...

Interactive Visualization and Analysis of Geospatial Data Sets - TrikeND-iGlobe

Science.gov (United States)

Rosebrock, Uwe; Hogan, Patrick; Chandola, Varun

2013-04-01

The visualization of scientific datasets is becoming an ever-increasing challenge as advances in computing technologies have enabled scientists to build high resolution climate models that have produced petabytes of climate data. To interrogate and analyze these large datasets in real-time is a task that pushes the boundaries of computing hardware and software. But integration of climate datasets with geospatial data requires considerable amount of effort and close familiarity of various data formats and projection systems, which has prevented widespread utilization outside of climate community. TrikeND-iGlobe is a sophisticated software tool that bridges this gap, allows easy integration of climate datasets with geospatial datasets and provides sophisticated visualization and analysis capabilities. The objective for TrikeND-iGlobe is the continued building of an open source 4D virtual globe application using NASA World Wind technology that integrates analysis of climate model outputs with remote sensing observations as well as demographic and environmental data sets. This will facilitate a better understanding of global and regional phenomenon, and the impact analysis of climate extreme events. The critical aim is real-time interactive interrogation. At the data centric level the primary aim is to enable the user to interact with the data in real-time for the purpose of analysis - locally or remotely. TrikeND-iGlobe provides the basis for the incorporation of modular tools that provide extended interactions with the data, including sub-setting, aggregation, re-shaping, time series analysis methods and animation to produce publication-quality imagery. TrikeND-iGlobe may be run locally or can be accessed via a web interface supported by high-performance visualization compute nodes placed close to the data. It supports visualizing heterogeneous data formats: traditional geospatial datasets along with scientific data sets with geographic coordinates (NetCDF, HDF, etc

Understanding Visual Novel As Artwork of Visual Communication Design

Directory of Open Access Journals (Sweden)

Dendi Pratama

2017-10-01

Full Text Available Visual Novel is a kind of audiovisual game that offers visual strength through the narrative and visual characters. The developer community of Visual Novel (VN Project Indonesia indicated a limited local game developer that produces Visual Novel of Indonesia. In addition, Indonesian Visual Novel production was also more influenced by the style of anime or manga from Japan. Actually, Visual Novel is part of the potential of  creative industries products. The study is to formulate the problem, how to understand Visual Novel as artwork of visual communication design, especially among students? This research is a case study conducted on visual communication design student at the University Indraprasta PGRI Jakarta. The results showed low levels of knowledge, understanding, and experience of  the Visual Novel game, which is below 50%. Qualitative and quantitative methods combined with structural semiotic approach is used to describe the elements of the design and the signs structure at the Visual Novel. This research can be a scientific reference for further introduce and encourage an understanding of Visual Novel as artwork of Visual Communication Design. In addition, the results may add to the knowledge of  society, and encourage the development of Visual Novel artwork that  reflect the culture of Indonesia. Visual Novel adalah sejenis permainan audiovisual yang menawarkan kekuatan visual melalui narasi dan karakter visual. Data dari komunitas pengembang Visual Novel (VN Project Indonesia menunjukkan masih terbatasnya pengembang game lokal yang memproduksi Visual Novel Indonesia. Selain itu, produksi Visual Novel Indonesia juga lebih banyak dipengaruhi oleh gaya anime dan manga dari Jepang. Padahal Visual Novel adalah bagian dari produk industri kreatif yang potensial. Studi ini merumuskan masalah, bagaimana memahami Visual Novel sebagai karya seni desain komunikasi visual, khususnya di kalangan mahasiswa? Penelitian ini merupakan studi kasus

Vividness of Visual Imagery Depends on the Neural Overlap with Perception in Visual Areas.

Science.gov (United States)

Dijkstra, Nadine; Bosch, Sander E; van Gerven, Marcel A J

2017-02-01

Research into the neural correlates of individual differences in imagery vividness point to an important role of the early visual cortex. However, there is also great fluctuation of vividness within individuals, such that only looking at differences between people necessarily obscures the picture. In this study, we show that variation in moment-to-moment experienced vividness of visual imagery, within human subjects, depends on the activity of a large network of brain areas, including frontal, parietal, and visual areas. Furthermore, using a novel multivariate analysis technique, we show that the neural overlap between imagery and perception in the entire visual system correlates with experienced imagery vividness. This shows that the neural basis of imagery vividness is much more complicated than studies of individual differences seemed to suggest. Visual imagery is the ability to visualize objects that are not in our direct line of sight: something that is important for memory, spatial reasoning, and many other tasks. It is known that the better people are at visual imagery, the better they can perform these tasks. However, the neural correlates of moment-to-moment variation in visual imagery remain unclear. In this study, we show that the more the neural response during imagery is similar to the neural response during perception, the more vivid or perception-like the imagery experience is. Copyright © 2017 the authors 0270-6474/17/371367-07$15.00/0.