Science.gov

Sample records for adult visual system

  1. Effect of acute and chronic bilateral visual deafferentation on c-Fos immunoreactivity in the visual system of adult rats.

    PubMed

    Wiedmann, Rhea; Rosahl, Steffen K; Brinker, Thomas; Samii, Madjid; Nakamura, Makoto

    2013-09-01

    In our study we examined acute and chronic changes in c-Fos expression patterns in the visual system of the rat after complete visual deafferentation. In 20 male Lewis rats, the retro-bulbar part of the optic nerve was sectioned bilaterally. Ten animals underwent c-Fos immunohistochemistry after 3 days and 10 animals after 3 weeks examining time-dependent changes. The control group consisted of 10 animals, which did not undergo any surgical manipulation. c-Fos expression in the rat visual system experienced significant changes after acute and chronic bilateral complete visual deafferentation. Acute decrease in c-Fos level was observed in the ventral lateral geniculate nucleus, intergeniculate leaflet, superficial gray layer of the superior colliculus and layers IV and V of the primary visual cortex. After chronic deafferentation, c-Fos expression was also found to be decreased in the optic and deep layers of the superior colliculus and layer VI of the primary visual cortex. No change in c-Fos expression was observed in the dorsal lateral geniculate nucleus and layers I, II and III of the primary visual cortex. This work shows that secondary complete blindness does not lead to uniform decrease in c-Fos levels in all subcortical and cortical brain regions related to vision. These findings provide important information concerning expression of the immediate-early gene product c-Fos in secondary blind rodent models. It may further serve as a relevant baseline finding when electrical stimulation of the visual system is performed, aiding the assessment of visual neuroprosthesis using c-Fos as a functional mapping tool when evaluating different stimulus parameters in blind rodent models.

  2. Retinal lesions induce fast intrinsic cortical plasticity in adult mouse visual system.

    PubMed

    Smolders, Katrien; Vreysen, Samme; Laramée, Marie-Eve; Cuyvers, Annemie; Hu, Tjing-Tjing; Van Brussel, Leen; Eysel, Ulf T; Nys, Julie; Arckens, Lutgarde

    2016-09-01

    Neuronal activity plays an important role in the development and structural-functional maintenance of the brain as well as in its life-long plastic response to changes in sensory stimulation. We characterized the impact of unilateral 15° laser lesions in the temporal lower visual field of the retina, on visually driven neuronal activity in the afferent visual pathway of adult mice using in situ hybridization for the activity reporter gene zif268. In the first days post-lesion, we detected a discrete zone of reduced zif268 expression in the contralateral hemisphere, spanning the border between the monocular segment of the primary visual cortex (V1) with extrastriate visual area V2M. We could not detect a clear lesion projection zone (LPZ) in areas lateral to V1 whereas medial to V2M, agranular and granular retrosplenial cortex showed decreased zif268 levels over their full extent. All affected areas displayed a return to normal zif268 levels, and this was faster in higher order visual areas than in V1. The lesion did, however, induce a permanent LPZ in the retinorecipient layers of the superior colliculus. We identified a retinotopy-based intrinsic capacity of adult mouse visual cortex to recover from restricted vision loss, with recovery speed reflecting the areal cortical magnification factor. Our observations predict incomplete visual field representations for areas lateral to V1 vs. lack of retinotopic organization for areas medial to V2M. The validation of this mouse model paves the way for future interrogations of cortical region- and cell-type-specific contributions to functional recovery, up to microcircuit level.

  3. Functional visualization of the excretory system of adult Schistosoma mansoni by the fluorescent marker resorufin.

    PubMed

    Sato, H; Kusel, J R; Thornhill, J

    2002-12-01

    Excretion of metabolic wastes as well as xenobiotics is a major concern of all living organisms, and the Platyhelminthes including Schistosoma mansoni possess the protonephridial excretory system for their survival. Except for some ultra-structural and biochemical information, little is known about the protonephridium of platyhelminths due to a lack of established techniques for exploring the excretory activity. This study describes a new technique to assess the excretory activity of S. mansoni by use of the fluorescent marker resorufin, which is a potential substrate of the drug efflux pump, P-glycoprotein. After simple diffusion into the schistosome body, fluorescent resorufin was concentrated in the excretory tubules by an energy-dependent mechanism and excreted via the nephridiopore. The present technique of labelling functionally the excretory system was applicable to adult worms, but not schistosomula or cercariae. A variety of modulators known to interfere with mammalian P-glycoprotein function perturbed resorufin excretion from male adult schistosomes, including cyclosporin A, Ro11-2933, verapamil, or nifedipine. This technique of labelling the excretory system with fluorescent resorufin has enabled us to study aspects of the physiological function, hitherto unknown, of the protonephridial system of S. mansoni.

  4. Brain system size and adult-adult play in primates: a comparative analysis of the roles of the non-visual neocortex and the amygdala.

    PubMed

    Pellis, Sergio M; Iwaniuk, Andrew N

    2002-08-21

    Recent studies have shown that contrary to expectation, larger-brained species within mammalian orders are not more likely to engage in play. This is true for juvenile rodents, juvenile marsupials and adult primates. Neither does the relative size of the neocortex predict the prevalence of play in species of marsupials and primates. Two methodological limitations may account for the lack of such relationships. Firstly, play may only vary systematically with specific brain areas, not overall size increases in brain tissue. Secondly, the play indices used to measure the variation in play across species may be insufficiently sensitive to the effects of changes in brain size. In this study, we attempt to deal with the first methodological problem. The adult-adult play fighting among species of primates was correlated with the relative size of the non-visual cortex and the amygdala. The statistical analyses used took into account the problems of scaling and corrected for degree of phylogenetic relatedness among the species. The size of the non-visual cortex failed to predict the prevalence of play fighting occurring in either sexual or non-sexual contexts. In contrast, the size of the amygdala significantly predicted the prevalence of sexual play, but not non-sexual play. That is, species with larger sized amygdala are more likely to engage in sexual play. These findings provide new insights into the role of different brain systems in the regulation of play behavior.

  5. Educator Perceptions of Visual Support Systems and Social Skills for Young Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Miller, David James

    2016-01-01

    Young adults with Autism Spectrum Disorder (ASD) face unique social skills challenges as they transition into independent living environments and seek fulfilling relationships within their communities. Research has focused on social education and interventions for children with autism, while transitioning young adults with ASD have received…

  6. Visualization of adult stem cells within their niches using the Drosophila germline as a model system.

    PubMed

    König, Annekatrin; Shcherbata, Halyna R

    2013-01-01

    The germaria of the fruit fly Drosophila melanogaster present an excellent model to study germline stem cell-niche interactions. Two to three adult stem cells are surrounded by a number of somatic cells that form the niche. Here we describe how Drosophilae germaria can be dissected and specifically immuno-stained to allow for identification and analysis of both the adult stem cells and their somatic niche cells.

  7. Ontogenetic improvement of visual function in the medaka Oryzias latipes based on an optomotor testing system for larval and adult fish

    USGS Publications Warehouse

    Carvalho, Paulo S. M.; Noltie, Douglas B.; Tillitt, D.E.

    2002-01-01

    We developed a system for evaluation of visual function in larval and adult fish. Both optomotor (swimming) and optokinetic (eye movement) responses were monitored and recorded using a system of rotating stripes. The system allowed manipulation of factors such as width of the stripes used, rotation speed of the striped drum, and light illuminance levels within both the scotopic and photopic ranges. Precise control of these factors allowed quantitative measurements of visual acuity and motion detection. Using this apparatus, we tested the hypothesis that significant posthatch ontogenetic improvements in visual function occur in the medaka Oryzias latipes, and also that this species shows significant in ovo neuronal development. Significant improvements in the acuity angle alpha (ability to discriminate detail) were observed from approximately 5 degrees at hatch to 1 degree in the oldest adult stages. In addition, we measured a significant improvement in flicker fusion thresholds (motion detection skills) between larval and adult life stages within both the scotopic and photopic ranges of light illuminance. Ranges of flicker fusion thresholds (X?? ?? SD) at log I=1.96 (photopic) varied from 37.2 ?? 1.6 cycles/s in young adults to 18.6 ?? 1.6 cycles/s in young larvae 10 days posthatch. At log I= - 2.54 (scotopic), flicker fusion thresholds varied from 5.8 ?? 0.7 cycles/s in young adults to 1.7 ?? 0.4 cycles/s in young larvae 10 days posthatch. Light sensitivity increased approximately 2.9 log units from early hatched larval stages to adults. The demonstrated ontogenetic improvements in visual function probably enable the fish to explore new resources, thereby enlarging their fundamental niche. ?? 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.

  8. Visual Alert System

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A visual alert system resulted from circuitry developed by Applied Cybernetics Systems for Langley as part of a space related telemetry system. James Campman, Applied Cybernetics president, left the company and founded Grace Industries, Inc. to manufacture security devices based on the Langley technology. His visual alert system combines visual and audible alerts for hearing impaired people. The company also manufactures an arson detection device called the electronic nose, and is currently researching additional applications of the NASA technology.

  9. Visual Function and Visual Acuity in an Urban Adult Population.

    ERIC Educational Resources Information Center

    Katz, J.; Tielsch, J. M.

    1996-01-01

    A survey of 6,850 adults age 40 or over concerning the effects of poor vision found that difficulties with reading or other near-vision activities were the most common complaint. One-fourth reported limitations in activities because of poor vision. Factors associated with loss of visual function were general health status, educational level, and…

  10. Conducting research with visually impaired older adults.

    PubMed

    Moore, Linda Weaver

    2002-04-01

    Due to the frequency of eye disorders among older adults, qualitative researchers who involve older individuals in their work must be sensitive to the multiple ways in which visual deficits can influence the research process. The author addresses some of the difficulties encountered, insights gained, and strategies developed while conducting a phenomenological study in which all the participants were severely visually impaired. The author's insights, drawn from personal experiences, reflections, and log entries kept throughout the study, are shared to help other researchers design and implement studies in which the voices of individuals with severe visual impairments can be skillfully tapped.

  11. Services for Visually Impaired Adults in Canada.

    ERIC Educational Resources Information Center

    Magarrell, G.

    1990-01-01

    The article examines the partnership between the Canadian government and nonprofit organizations in delivering rehabilitation services to blind/visually impaired adults. Discussed are legislation, concessions to blind persons, services of the Canadian National Institute for the Blind, special equipment, dog guide schools, consumer groups, and the…

  12. The Visual System

    MedlinePlus

    ... NEI for Kids > The Visual System All About Vision About the Eye Ask a Scientist Video Series ... Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun ...

  13. An Evaluation of a Visual Biofeedback Intervention in Dyslexic Adults

    ERIC Educational Resources Information Center

    Liddle, Elizabeth; Jackson, Georgina; Jackson, Stephen

    2005-01-01

    A prototype of a biofeedback system designed to treat dyslexia by improving heart-rate variability was evaluated in a single blind study of dyslexic adults. Treatment consisted of four 15 minute exposures to a visual display synchronized with either the participant's own cardiac cycle (intervention condition), or of a synthesized cardiac cycle…

  14. Solar System Visualizations

    NASA Technical Reports Server (NTRS)

    Brown, Alison M.

    2005-01-01

    Solar System Visualization products enable scientists to compare models and measurements in new ways that enhance the scientific discovery process, enhance the information content and understanding of the science results for both science colleagues and the public, and create.visually appealing and intellectually stimulating visualization products. Missions supported include MER, MRO, and Cassini. Image products produced include pan and zoom animations of large mosaics to reveal the details of surface features and topography, animations into registered multi-resolution mosaics to provide context for microscopic images, 3D anaglyphs from left and right stereo pairs, and screen captures from video footage. Specific products include a three-part context animation of the Cassini Enceladus encounter highlighting images from 350 to 4 meter per pixel resolution; Mars Reconnaissance Orbiter screen captures illustrating various instruments during assembly and testing at the Payload Hazardous Servicing Facility at Kennedy Space Center; and an animation of Mars Exploration Rover Opportunity's 'Rub al Khali' panorama where the rover was stuck in the deep fine sand for more than a month. This task creates new visualization products that enable new science results and enhance the public's understanding of the Solar System and NASA's missions of exploration.

  15. Exogenous Modulation of Retinoic Acid Signaling Affects Adult RGC Survival in the Frog Visual System after Optic Nerve Injury

    PubMed Central

    Duprey-Díaz, Mildred V.; Blagburn, Jonathan M.; Blanco, Rosa E.

    2016-01-01

    After lesions to the mammalian optic nerve, the great majority of retinal ganglion cells (RGCs) die before their axons have even had a chance to regenerate. Frog RGCs, on the other hand, suffer only an approximately 50% cell loss, and we have previously investigated the mechanisms by which the application of growth factors can increase their survival rate. Retinoic acid (RA) is a vitamin A-derived lipophilic molecule that plays major roles during development of the nervous system. The RA signaling pathway is also present in parts of the adult nervous system, and components of it are upregulated after injury in peripheral nerves but not in the CNS. Here we investigate whether RA signaling affects long-term RGC survival at 6 weeks after axotomy. Intraocular injection of all-trans retinoic acid (ATRA), the retinoic acid receptor (RAR) type-α agonist AM80, the RARβ agonist CD2314, or the RARγ agonist CD1530, returned axotomized RGC numbers to almost normal levels. On the other hand, inhibition of RA synthesis with disulfiram, or of RAR receptors with the pan-RAR antagonist Ro-41-5253, or the RARβ antagonist LE135E, greatly reduced the survival of the axotomized neurons. Axotomy elicited a strong activation of the MAPK, STAT3 and AKT pathways; this activation was prevented by disulfiram or by RAR antagonists. Finally, addition of exogenous ATRA stimulated the activation of the first two of these pathways. Future experiments will investigate whether these strong survival-promoting effects of RA are mediated via the upregulation of neurotrophins. PMID:27611191

  16. Adult Visual Experience Promotes Recovery of Primary Visual Cortex from Long-Term Monocular Deprivation

    ERIC Educational Resources Information Center

    Fischer, Quentin S.; Aleem, Salman; Zhou, Hongyi; Pham, Tony A.

    2007-01-01

    Prolonged visual deprivation from early childhood to maturity is believed to cause permanent visual impairment. However, there have been case reports of substantial improvement of binocular vision in human adults following lifelong visual impairment or deprivation. These observations, together with recent findings of adult ocular dominance…

  17. Peripheral Visual Reaction Time Is Faster in Deaf Adults and British Sign Language Interpreters than in Hearing Adults.

    PubMed

    Codina, Charlotte J; Pascalis, Olivier; Baseler, Heidi A; Levine, Alexandra T; Buckley, David

    2017-01-01

    Following auditory deprivation, the remaining sense of vision has shown selective enhancement in visual cognition, especially in the area of near peripheral vision. Visual acuity is poor in the far periphery and may be an area where sound confers the greatest advantage in hearing persons. Experience with a visuospatial language such as British Sign Language (BSL) makes additional demands on the visual system. To test the different and separable effects of deafness and use of a visuo-spatial language on far peripheral visual processing, we investigated visual reaction times (RTs) and response accuracy to visual stimuli, between 30° and 85° along the four cardinal and four inter-cardinal meridians. We used three luminances of static, briefly illuminated stimuli in visually normal adults. The cohort tested included profoundly congenitally deaf adults (N = 17), hearing fluent BSL users (N = 8) and hearing non-signing adults (N = 18). All participants were tested using a peripheral forced choice paradigm designed previously to test deaf and hearing children (Codina et al., 2011a). Deaf adults demonstrated significantly faster RTs to all far peripheral stimuli and exceeded the abilities of both signing and non-signing hearing adults. Deaf adults were significantly faster than BSL interpreters, who in turn were significantly faster than hearing non-signing adults. The differences in RT demonstrated between groups were consistent across all visual field meridians and were not localized to any one region of the visual field. There were no differences found between any groups in accuracy of detecting these static stimuli at any retinal location. Early onset auditory deprivation appears to lead to a response time visual advantage in far peripheral responses to briefly presented, static LED stimuli, especially in the right visual field. Fluency in BSL facilitates faster visuo-motor responses in the peripheral visual field, but to a lesser extent than congenital, profound

  18. Peripheral Visual Reaction Time Is Faster in Deaf Adults and British Sign Language Interpreters than in Hearing Adults

    PubMed Central

    Codina, Charlotte J.; Pascalis, Olivier; Baseler, Heidi A.; Levine, Alexandra T.; Buckley, David

    2017-01-01

    Following auditory deprivation, the remaining sense of vision has shown selective enhancement in visual cognition, especially in the area of near peripheral vision. Visual acuity is poor in the far periphery and may be an area where sound confers the greatest advantage in hearing persons. Experience with a visuospatial language such as British Sign Language (BSL) makes additional demands on the visual system. To test the different and separable effects of deafness and use of a visuo-spatial language on far peripheral visual processing, we investigated visual reaction times (RTs) and response accuracy to visual stimuli, between 30° and 85° along the four cardinal and four inter-cardinal meridians. We used three luminances of static, briefly illuminated stimuli in visually normal adults. The cohort tested included profoundly congenitally deaf adults (N = 17), hearing fluent BSL users (N = 8) and hearing non-signing adults (N = 18). All participants were tested using a peripheral forced choice paradigm designed previously to test deaf and hearing children (Codina et al., 2011a). Deaf adults demonstrated significantly faster RTs to all far peripheral stimuli and exceeded the abilities of both signing and non-signing hearing adults. Deaf adults were significantly faster than BSL interpreters, who in turn were significantly faster than hearing non-signing adults. The differences in RT demonstrated between groups were consistent across all visual field meridians and were not localized to any one region of the visual field. There were no differences found between any groups in accuracy of detecting these static stimuli at any retinal location. Early onset auditory deprivation appears to lead to a response time visual advantage in far peripheral responses to briefly presented, static LED stimuli, especially in the right visual field. Fluency in BSL facilitates faster visuo-motor responses in the peripheral visual field, but to a lesser extent than congenital, profound

  19. Grief and Needs of Adults with Acquired Visual Impairments

    ERIC Educational Resources Information Center

    Murray, Shirley A.; McKay, Robert C.; Nieuwoudt, Johan M.

    2010-01-01

    This report aims to illuminate the complex phenomenon of grief and the needs experienced throughout the time course of their impairments by adults with acquired visual impairments. The study applied a phenomenological research strategy using 10 case studies of South African adults, visually impaired within and beyond six years. Qualitative…

  20. GVS - GENERAL VISUALIZATION SYSTEM

    NASA Technical Reports Server (NTRS)

    Keith, S. R.

    1994-01-01

    The primary purpose of GVS (General Visualization System) is to support scientific visualization of data output by the panel method PMARC_12 (inventory number ARC-13362) on the Silicon Graphics Iris computer. GVS allows the user to view PMARC geometries and wakes as wire frames or as light shaded objects. Additionally, geometries can be color shaded according to phenomena such as pressure coefficient or velocity. Screen objects can be interactively translated and/or rotated to permit easy viewing. Keyframe animation is also available for studying unsteady cases. The purpose of scientific visualization is to allow the investigator to gain insight into the phenomena they are examining, therefore GVS emphasizes analysis, not artistic quality. GVS uses existing IRIX 4.0 image processing tools to allow for conversion of SGI RGB files to other formats. GVS is a self-contained program which contains all the necessary interfaces to control interaction with PMARC data. This includes 1) the GVS Tool Box, which supports color histogram analysis, lighting control, rendering control, animation, and positioning, 2) GVS on-line help, which allows the user to access control elements and get information about each control simultaneously, and 3) a limited set of basic GVS data conversion filters, which allows for the display of data requiring simpler data formats. Specialized controls for handling PMARC data include animation and wakes, and visualization of off-body scan volumes. GVS is written in C-language for use on SGI Iris series computers running IRIX. It requires 28Mb of RAM for execution. Two separate hardcopy documents are available for GVS. The basic document price for ARC-13361 includes only the GVS User's Manual, which outlines major features of the program and provides a tutorial on using GVS with PMARC_12 data. Programmers interested in modifying GVS for use with data in formats other than PMARC_12 format may purchase a copy of the draft GVS 3.1 Software Maintenance

  1. Complex Digital Visual Systems

    ERIC Educational Resources Information Center

    Sweeny, Robert W.

    2013-01-01

    This article identifies possibilities for data visualization as art educational research practice. The author presents an analysis of the relationship between works of art and digital visual culture, employing aspects of network analysis drawn from the work of Barabási, Newman, and Watts (2006) and Castells (1994). Describing complex network…

  2. Helicopter Visual Aid System

    NASA Technical Reports Server (NTRS)

    Baisley, R. L.

    1973-01-01

    The results of an evaluation of police helicopter effectiveness revealed a need for improved visual capability. A JPL program developed a method that would enhance visual observation capability for both day and night usage and demonstrated the feasibility of the adopted approach. This approach made use of remote pointable optics, a display screen, a slaved covert searchlight, and a coupled camera. The approach was proved feasible through field testing and by judgement against evaluation criteria.

  3. Visual recognition training of older adults with speech spectrograms.

    PubMed

    Drummond, S S; Dancer, J; Casey, B E; O'Sullivan, P

    1996-04-01

    10 adults' performances on visual training through recognition of speech spectrograms were examined. All subjects completed the training within eight 1-hr. sessions. Success and retention of training were also evident in the subjects' performances on two posttests.

  4. Visual learning in the hyperacuity range in adults.

    PubMed

    Fahle, M

    1993-04-01

    We investigated the amount, speed, and specificity of the learning of new visual tasks in adult humans using stereoscopic depth perception and vernier discrimination as the sensitive probes for learning. The results of psychophysical experiments in untrained adult observers indicate two phases of highly specific perceptual learning in humans: a fast phase and a slower one. Both types of learning might take place relatively "early" during pattern recognition in the visual cortex, since learning was very specific, without transfer between different stimulus orientations.

  5. Impaired Visual Motor Coordination in Obese Adults

    PubMed Central

    O'Shea, Donal

    2016-01-01

    Objective. To investigate whether obesity alters the sensory motor integration process and movement outcome during a visual rhythmic coordination task. Methods. 88 participants (44 obese and 44 matched control) sat on a chair equipped with a wrist pendulum oscillating in the sagittal plane. The task was to swing the pendulum in synchrony with a moving visual stimulus displayed on a screen. Results. Obese participants demonstrated significantly (p < 0.01) higher values for continuous relative phase (CRP) indicating poorer level of coordination, increased movement variability (p < 0.05), and a larger amplitude (p < 0.05) than their healthy weight counterparts. Conclusion. These results highlight the existence of visual sensory integration deficiencies for obese participants. The obese group have greater difficulty in synchronizing their movement with a visual stimulus. Considering that visual motor coordination is an essential component of many activities of daily living, any impairment could significantly affect quality of life. PMID:27994885

  6. Impaired Visual Motor Coordination in Obese Adults.

    PubMed

    Gaul, David; Mat, Arimin; O'Shea, Donal; Issartel, Johann

    2016-01-01

    Objective. To investigate whether obesity alters the sensory motor integration process and movement outcome during a visual rhythmic coordination task. Methods. 88 participants (44 obese and 44 matched control) sat on a chair equipped with a wrist pendulum oscillating in the sagittal plane. The task was to swing the pendulum in synchrony with a moving visual stimulus displayed on a screen. Results. Obese participants demonstrated significantly (p < 0.01) higher values for continuous relative phase (CRP) indicating poorer level of coordination, increased movement variability (p < 0.05), and a larger amplitude (p < 0.05) than their healthy weight counterparts. Conclusion. These results highlight the existence of visual sensory integration deficiencies for obese participants. The obese group have greater difficulty in synchronizing their movement with a visual stimulus. Considering that visual motor coordination is an essential component of many activities of daily living, any impairment could significantly affect quality of life.

  7. Visual Arts in Counselling Adults with Depressive Disorders

    ERIC Educational Resources Information Center

    Lee, Khai Ling; Mustaffa, M. S.; Tan, S. Y.

    2017-01-01

    This study provides a better understanding of using visual arts in counselling adults with depressive disorders. Three in-depth case studies were conducted in the counselling unit of a mental health hospital in Malaysia. Both qualitative and quantitative research methods were applied to explore three adult participants' counselling experiences.…

  8. Clinical Assessment of Functional Movement in Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Ray, Christopher T.; Horvat, Michael; Williams, Michael; Blasch, Bruce B.

    2007-01-01

    Adults with visual impairments have significantly more health risks than do sighted adults because of a number of factors, including the lower mineral density of their femoral neck bones, which is indicative of reduced weight-bearing exercise; their lesser maximal strength; and their higher rates of stroke, osteoporosis, depression, hypertension,…

  9. Science information systems: Visualization

    NASA Technical Reports Server (NTRS)

    Wall, Ray J.

    1991-01-01

    Future programs in earth science, planetary science, and astrophysics will involve complex instruments that produce data at unprecedented rates and volumes. Current methods for data display, exploration, and discovery are inadequate. Visualization technology offers a means for the user to comprehend, explore, and examine complex data sets. The goal of this program is to increase the effectiveness and efficiency of scientists in extracting scientific information from large volumes of instrument data.

  10. Nogo-A deletion increases the plasticity of the optokinetic response and changes retinal projection organization in the adult mouse visual system.

    PubMed

    Guzik-Kornacka, Anna; van der Bourg, Alexander; Vajda, Flora; Joly, Sandrine; Christ, Franziska; Schwab, Martin E; Pernet, Vincent

    2016-01-01

    The inhibitory action of Nogo-A on axonal growth has been well described. However, much less is known about the effects that Nogo-A could exert on the plasticity of neuronal circuits under physiological conditions. We investigated the effects of Nogo-A knock-out (KO) on visual function of adult mice using the optokinetic response (OKR) and the monocular deprivation (MD)-induced OKR plasticity and analyzed the anatomical organization of the eye-specific retinal projections. The spatial frequency sensitivity was higher in intact Nogo-A KO than in wild-type (WT) mice. After MD, Nogo-A KO mice reached a significantly higher spatial frequency and contrast sensitivity. Bilateral ablation of the visual cortex did not affect the OKR sensitivity before MD but reduced the MD-induced enhancement of OKR by approximately 50% in Nogo-A KO and WT mice. These results suggest that cortical and subcortical brain structures contribute to the OKR plasticity. The tracing of retinal projections to the dorsal lateral geniculate nucleus (dLGN) revealed that the segregation of eye-specific terminals was decreased in the adult Nogo-A KO dLGN compared with WT mice. Strikingly, MD of the right eye led to additional desegregation of retinal projections in the left dLGN of Nogo-A KO but not in WT mice. In particular, MD promoted ectopic varicosity formation in Nogo-A KO dLGN axons. The present data show that Nogo-A restricts visual experience-driven plasticity of the OKR and plays a role in the segregation and maintenance of retinal projections to the brain.

  11. Evaluating the Establishment and Maintenance of Visual-Visual and Gustatory-Visual Equivalence Relations in Adults With Developmental Disabilities

    ERIC Educational Resources Information Center

    Rehfeldt, Ruth Anne; Dixon, Mark R.

    2005-01-01

    Four adults with developmental disabilities were taught to make conditional discriminations between either pictures and their corresponding printed English and Spanish words, or tastes and their corresponding printed English and Spanish words. Participants required more training trials to master the visual-visual conditional discriminations than…

  12. Visualizing Parallel Computer System Performance

    NASA Technical Reports Server (NTRS)

    Malony, Allen D.; Reed, Daniel A.

    1988-01-01

    Parallel computer systems are among the most complex of man's creations, making satisfactory performance characterization difficult. Despite this complexity, there are strong, indeed, almost irresistible, incentives to quantify parallel system performance using a single metric. The fallacy lies in succumbing to such temptations. A complete performance characterization requires not only an analysis of the system's constituent levels, it also requires both static and dynamic characterizations. Static or average behavior analysis may mask transients that dramatically alter system performance. Although the human visual system is remarkedly adept at interpreting and identifying anomalies in false color data, the importance of dynamic, visual scientific data presentation has only recently been recognized Large, complex parallel system pose equally vexing performance interpretation problems. Data from hardware and software performance monitors must be presented in ways that emphasize important events while eluding irrelevant details. Design approaches and tools for performance visualization are the subject of this paper.

  13. Adult Word Recognition and Visual Sequential Memory

    ERIC Educational Resources Information Center

    Holmes, V. M.

    2012-01-01

    Two experiments were conducted investigating the role of visual sequential memory skill in the word recognition efficiency of undergraduate university students. Word recognition was assessed in a lexical decision task using regularly and strangely spelt words, and nonwords that were either standard orthographically legal strings or items made from…

  14. Community Service by Visually Impaired Older Adults.

    ERIC Educational Resources Information Center

    Berkman, Susan C. J.

    1984-01-01

    The Braille Institute's Community Outreach Program provides adventitiously blinded older adults with opportunities to volunteer in local community agencies, schools, and hospitals upon completion of the institute's special education program. Students use new independence skills in a functional social environment, thereby increasing their…

  15. Immersive Visual Programming System

    DTIC Science & Technology

    1995-03-16

    improved virtual programming system. 20 It is another object to provide a virtual programming system that optimally increases a user’s comprehensibility...of program structures. NAVY CASE NO. 75554 It is still another object to provide a virtual programming system that is useful for defining the high...level flow control and data pathways within a program. It is yet another object to provide a virtual programming system that allows for dynamic

  16. VISUAL ALARM SYSTEM

    DOEpatents

    Morris, J.M.

    1958-11-01

    A vlsual alarm system, particularly a system incorporating a gas-fllled diode glow bulb, for indicating a minor alarm and also a major alarm is presented. In operation, the disclosed system responds to a signal indlcative of a caution condition by applying a d-c voltage across the glow bulb to induce a glow at one electrode. If a signal indicative of a critlcal condition is received, the system applies an a-c voltage across tbe glow bulb to produce a glow discharge at each electrode.

  17. Solar System Visualization (SSV) Project

    NASA Technical Reports Server (NTRS)

    Todd, Jessida L.

    2005-01-01

    The Solar System Visualization (SSV) project aims at enhancing scientific and public understanding through visual representations and modeling procedures. The SSV project's objectives are to (1) create new visualization technologies, (2) organize science observations and models, and (3) visualize science results and mission Plans. The SSV project currently supports the Mars Exploration Rovers (MER) mission, the Mars Reconnaissance Orbiter (MRO), and Cassini. In support of the these missions, the SSV team has produced pan and zoom animations of large mosaics to reveal details of surface features and topography, created 3D animations of science instruments and procedures, formed 3-D anaglyphs from left and right stereo pairs, and animated registered multi-resolution mosaics to provide context for microscopic images.

  18. Visual speech gestures modulate efferent auditory system.

    PubMed

    Namasivayam, Aravind Kumar; Wong, Wing Yiu Stephanie; Sharma, Dinaay; van Lieshout, Pascal

    2015-03-01

    Visual and auditory systems interact at both cortical and subcortical levels. Studies suggest a highly context-specific cross-modal modulation of the auditory system by the visual system. The present study builds on this work by sampling data from 17 young healthy adults to test whether visual speech stimuli evoke different responses in the auditory efferent system compared to visual non-speech stimuli. The descending cortical influences on medial olivocochlear (MOC) activity were indirectly assessed by examining the effects of contralateral suppression of transient-evoked otoacoustic emissions (TEOAEs) at 1, 2, 3 and 4 kHz under three conditions: (a) in the absence of any contralateral noise (Baseline), (b) contralateral noise + observing facial speech gestures related to productions of vowels /a/ and /u/ and (c) contralateral noise + observing facial non-speech gestures related to smiling and frowning. The results are based on 7 individuals whose data met strict recording criteria and indicated a significant difference in TEOAE suppression between observing speech gestures relative to the non-speech gestures, but only at the 1 kHz frequency. These results suggest that observing a speech gesture compared to a non-speech gesture may trigger a difference in MOC activity, possibly to enhance peripheral neural encoding. If such findings can be reproduced in future research, sensory perception models and theories positing the downstream convergence of unisensory streams of information in the cortex may need to be revised.

  19. The Visualization Management System Approach To Visualization In Scientific Computing

    NASA Astrophysics Data System (ADS)

    Butler, David M.; Pendley, Michael H.

    1989-09-01

    We introduce the visualization management system (ViMS), a new approach to the development of software for visualization in scientific computing (ViSC). The conceptual foundation for a ViMS is an abstract visualization model which specifies a class of geometric objects, the graphic representations of the objects and the operations on both. A ViMS provides a modular implementation of its visualization model. We describe ViMS requirements and a model-independent ViMS architecture. We briefly describe the vector bundle visualization model and the visualization taxonomy it generates. We conclude by summarizing the benefits of the ViMS approach.

  20. Component-Based Visualization System

    NASA Technical Reports Server (NTRS)

    Delgado, Francisco

    2005-01-01

    A software system has been developed that gives engineers and operations personnel with no "formal" programming expertise, but who are familiar with the Microsoft Windows operating system, the ability to create visualization displays to monitor the health and performance of aircraft/spacecraft. This software system is currently supporting the X38 V201 spacecraft component/system testing and is intended to give users the ability to create, test, deploy, and certify their subsystem displays in a fraction of the time that it would take to do so using previous software and programming methods. Within the visualization system there are three major components: the developer, the deployer, and the widget set. The developer is a blank canvas with widget menu items that give users the ability to easily create displays. The deployer is an application that allows for the deployment of the displays created using the developer application. The deployer has additional functionality that the developer does not have, such as printing of displays, screen captures to files, windowing of displays, and also serves as the interface into the documentation archive and help system. The third major component is the widget set. The widgets are the visual representation of the items that will make up the display (i.e., meters, dials, buttons, numerical indicators, string indicators, and the like). This software was developed using Visual C++ and uses COTS (commercial off-the-shelf) software where possible.

  1. SUBSURFACE VISUAL ALARM SYSTEM ANALYSIS

    SciTech Connect

    D.W. Markman

    2001-08-06

    The ''Subsurface Fire Hazard Analysis'' (CRWMS M&O 1998, page 61), and the document, ''Title III Evaluation Report for the Surface and Subsurface Communication System'', (CRWMS M&O 1999a, pages 21 and 23), both indicate the installed communication system is adequate to support Exploratory Studies Facility (ESF) activities with the exception of the mine phone system for emergency notification purposes. They recommend the installation of a visual alarm system to supplement the page/party phone system The purpose of this analysis is to identify data communication highway design approaches, and provide justification for the selected or recommended alternatives for the data communication of the subsurface visual alarm system. This analysis is being prepared to document a basis for the design selection of the data communication method. This analysis will briefly describe existing data or voice communication or monitoring systems within the ESF, and look at how these may be revised or adapted to support the needed data highway of the subsurface visual alarm. system. The existing PLC communication system installed in subsurface is providing data communication for alcove No.5 ventilation fans, south portal ventilation fans, bulkhead doors and generator monitoring system. It is given that the data communication of the subsurface visual alarm system will be a digital based system. It is also given that it is most feasible to take advantage of existing systems and equipment and not consider an entirely new data communication system design and installation. The scope and primary objectives of this analysis are to: (1) Briefly review and describe existing available data communication highways or systems within the ESF. (2) Examine technical characteristics of an existing system to disqualify a design alternative is paramount in minimizing the number of and depth of a system review. (3) Apply general engineering design practices or criteria such as relative cost, and degree of

  2. Assertiveness by Older Adults with Visual Impairment: Context Matters

    ERIC Educational Resources Information Center

    Ryan, Ellen Bouchard; Anas, Ann P.; Mays, Heather

    2008-01-01

    Within a communication predicament of aging and disability framework, this study examined the impact of two types of contextual variation on perceptions of older adult assertiveness within problematic service encounters. Young (N = 66) and older (N = 66) participants evaluated conversational scenarios in which a visually-impaired older woman…

  3. Visual Object Pattern Separation Deficits in Nondemented Older Adults

    ERIC Educational Resources Information Center

    Toner, Chelsea K.; Pirogovsky, Eva; Kirwan, C. Brock; Gilbert, Paul E.

    2009-01-01

    Young and nondemented older adults were tested on a continuous recognition memory task requiring visual pattern separation. During the task, some objects were repeated across trials and some objects, referred to as lures, were presented that were similar to previously presented objects. The lures resulted in increased interference and an increased…

  4. Visual Object Pattern Separation Varies in Older Adults

    ERIC Educational Resources Information Center

    Holden, Heather M.; Toner, Chelsea; Pirogovsky, Eva; Kirwan, C. Brock; Gilbert, Paul E.

    2013-01-01

    Young and nondemented older adults completed a visual object continuous recognition memory task in which some stimuli (lures) were similar but not identical to previously presented objects. The lures were hypothesized to result in increased interference and increased pattern separation demand. To examine variability in object pattern separation…

  5. Visual Arts and Older Adult Learners in Retirement

    ERIC Educational Resources Information Center

    Hunt, Irma

    2012-01-01

    The purpose of this study was to explore the role of visual arts and its impact on successful aging and older adult learners in retirement. Retirement is one of the most important economic, psychological, and social transitions in most people's lives. Longevity has increased in the last sixty years such that in 2010, the average person can…

  6. Visual Performance of Adults with Prelingual Auditory Impairment

    ERIC Educational Resources Information Center

    Rietveld, S.; Spiering, M.; Rotteveel, M.; van Beest, I.

    2004-01-01

    Reaction times and picture evaluations by 18 adults with hearing loss were compared with those of 18 matched controls during two visual priming tasks. In Task 1, participants reacted to sexual and plant target pictures (while influenced by similar preceding pictures) by pressing "sex" or "plant" buttons. In Task 2, they evaluated target Japanese…

  7. Visual function affects prosocial behaviors in older adults.

    PubMed

    Teoli, Dac A; Smith, Merideth D; Leys, Monique J; Jain, Priyanka; Odom, J Vernon

    2016-02-01

    Eye-related pathological conditions such as glaucoma, diabetic retinopathy, and age-related macular degeneration commonly lead to decreased peripheral/central field, decreased visual acuity, and increased functional disability. We sought to answer if relationships exist between measures of visual function and reported prosocial behaviors in an older adult population with eye-related diagnoses. The sample consisted of adults, aged ≥ 60 years old, at an academic hospital's eye institute. Vision ranged from normal to severe impairment. Medical charts determined the visual acuities, ocular disease, duration of disease (DD), and visual fields (VF). Measures of giving help were via validated questionnaires on giving formal support (GFS) and giving informal support; measures of help received were perceived support (PS) and informal support received (ISR). ISR had subscales: tangible support (ISR-T), emotional support (ISR-E), and composite (ISR-C). Visual acuities of the better and worse seeing eyes were converted to LogMAR values. VF information converted to a 4-point rating scale of binocular field loss severity. DD was in years. Among 96 participants (mean age 73.28; range 60-94), stepwise regression indicated a relationship of visual variables to GFS (p < 0.05; Multiple R (2) = 0.1679 with acuity-better eye, VF rating, and DD), PS (p < 0.05; Multiple R (2) = 0.2254 with acuity-better eye), ISR-C (p < 0.05; Multiple R (2) = 0.041 with acuity-better eye), and ISR-T (p < 0.05; Multiple R (2) = 0.1421 with acuity-better eye). The findings suggest eye-related conditions can impact levels and perceptions of support exchanges. Our data reinforces the importance of visual function as an influence on prosocial behavior in older adults.

  8. Fluoxetine increases plasticity and modulates the proteomic profile in the adult mouse visual cortex

    PubMed Central

    Ruiz-Perera, L.; Muniz, M.; Vierci, G.; Bornia, N.; Baroncelli, L.; Sale, A.; Rossi, F.M.

    2015-01-01

    The scarce functional recovery of the adult CNS following injuries or diseases is largely due to its reduced potential for plasticity, the ability to reorganize neural connections as a function of experience. Recently, some new strategies restoring high levels of plasticity in the adult brain have been identified, especially in the paradigmatic model of the visual system. A chronic treatment with the anti-depressant fluoxetine reinstates plasticity in the adult rat primary visual cortex, inducing recovery of vision in amblyopic animals. The molecular mechanisms underlying this effect remain largely unknown. Here, we explored fluoxetine effects on mouse visual cortical plasticity, and exploited a proteomic approach to identify possible candidates mediating the outcome of the antidepressant treatment on adult cortical plasticity. We showed that fluoxetine restores ocular dominance plasticity in the adult mouse visual cortex, and identified 31 differentially expressed protein spots in fluoxetine-treated animals vs. controls. MALDITOF/TOF mass spectrometry identification followed by bioinformatics analysis revealed that these proteins are involved in the control of cytoskeleton organization, endocytosis, molecular transport, intracellular signaling, redox cellular state, metabolism and protein degradation. Altogether, these results indicate a complex effect of fluoxetine on neuronal signaling mechanisms potentially involved in restoring plasticity in the adult brain. PMID:26205348

  9. Effect of visual perception, visual function, cognition, and personality on power wheelchair use in adults.

    PubMed

    Massengale, Samantha; Folden, Donna; McConnell, Pima; Stratton, Laurie; Whitehead, Victoria

    2005-01-01

    The purpose of this study was to determine to what extent visual perception, visual function, cognition, and personality traits affect power wheelchair use in adults. It also proposes to establish baseline information to help clinicians determine or predict power wheelchair driving performance and to develop service plans to address those driving skills that need improvement or compensation. Sixty-two adult power wheelchair users were recruited. Standardized instruments were used to evaluate visual perceptual skills, visual function, cognitive skills, and personality traits. The results of these evaluations were then correlated with participants' scores on a power wheelchair performance test. Strong correlations were found between power wheelchair driving performance and visual perception (p = .000), ocular motor function (p = .000 and p < or = .001), stereodepth perception (p < or = .001), and alertness to the environment (p < or = .001). No significant correlations were found between personality traits and power wheelchair driving performance. These results indicate that good visual perceptual skills, visual function, and various aspects of cognition are necessary for proficient power wheelchair use. These data will assist clinicians in identifying significant factors to consider when evaluating and training clients for power wheelchair use.

  10. Effects of combining a cryptochrome mutation with other visual-system variants on entrainment of locomotor and adult-emergence rhythms in Drosophila.

    PubMed

    Mealey-Ferrara, Marion L; Montalvo, Alexandra G; Hall, Jeffrey C

    2003-01-01

    "For every behavioral observation, there is an equal and opposite observation." S. Benzer Photoreception is an important component of rhythm systems and is involved in adjusting circadian clocks to photic features of daily cycles. In Drosophila, it has been suggested that there are three light input pathways to the clock that underlie rhythms of adult behavior: One involves the eyes; the other two extraocular photoreception through a structure called the Hofbauer-Buchner (H-B) eyelet and light reception carried out by pacemaker neurons themselves, mediated by a substance called cryptochrome. All photoreceptor cells including the H-B eyelet have been surmised to be removed by glass-null mutations. Mutations in the no-receptor-potential-A (norpA) gene cause the compound eyes and ocelli to be non-functional and may also affect the eyelet's function. The one cryptochrome mutant known (cryb) harbors an amino-acid substitution in the blue-light absorbing protein encoded by this gene. With regard to adult locomotor rhythms, all single mutants (gl60j, norpAP41, and cryb) re-entrained to altered light:dark (LD) cycles in which the L phase involved relatively intense light. Dropping light levels ca. 10 or ca. 30-fold permitted small percentages of doubly-mutant gl60j cryb flies clearly to re-synchronize their behavior. The marginal re-entrainability in the lowest-light situation nevertheless involved superior responsiveness of the gl60j cryb type, compared with that observed previously using a different re-entrainment protocol. Furthermore, transgenic types in which rhodopsin-expressing cells within the H-B eyelet were ablated or suffered from the effects of tetanus-toxin also entrained with behavior similar or superior to that of gl60j cryb at a low light level. Light inputs that are necessary to synchronize periodic adult emergence can be inferred (from previous studies) to involve a cry-dependent pathway and perhaps also a norpA-dependent one, so that combining mutations

  11. Social support and depression of adults with visual impairments.

    PubMed

    Papadopoulos, Konstantinos; Papakonstantinou, Doxa; Montgomery, Anthony; Solomou, Argyro

    2014-07-01

    Relatively little research exists with regard to the relationship between social support and depression among adults with visual impairments. Such a gap is noteworthy when one considers that individuals become more dependent on others as they enter middle and late adulthood. The present research will examine the association between social networks, social support and depression among adults with visual impairments. Seventy-seven adults with visual impairments participated in the study. Depression, social network and emotional/practical social support were measured with self-report measures. Additionally, the degree to which emotional/practical social support received were positive or negative and the ability of respondents to self-manage their daily living were assessed. Less than a third of respondents scored above the threshold for depressive symptoms. Depressive symptoms were not related to gender or vision status. Depression was correlated with age, educational level, less positive practical support, more negative practical support and more negative emotional support, with lower perceptions of self-management representing the most robust predictor of depression. Age moderated the relationship between depression and self-management, and between depression and negative emotional support. Lower perceptions of self-management and negative emotional support were significantly associated with depressive symptoms.

  12. The role of visual spatial attention in adult developmental dyslexia.

    PubMed

    Collis, Nathan L; Kohnen, Saskia; Kinoshita, Sachiko

    2013-01-01

    The present study investigated the nature of visual spatial attention deficits in adults with developmental dyslexia, using a partial report task with five-letter, digit, and symbol strings. Participants responded by a manual key press to one of nine alternatives, which included other characters in the string, allowing an assessment of position errors as well as intrusion errors. The results showed that the dyslexic adults performed significantly worse than age-matched controls with letter and digit strings but not with symbol strings. Both groups produced W-shaped serial position functions with letter and digit strings. The dyslexics' deficits with letter string stimuli were limited to position errors, specifically at the string-interior positions 2 and 4. These errors correlated with letter transposition reading errors (e.g., reading slat as "salt"), but not with the Rapid Automatized Naming (RAN) task. Overall, these results suggest that the dyslexic adults have a visual spatial attention deficit; however, the deficit does not reflect a reduced span in visual-spatial attention, but a deficit in processing a string of letters in parallel, probably due to difficulty in the coding of letter position.

  13. Prevalence and causes of visual impairment among Saudi adults

    PubMed Central

    Parrey, Mujeeb Ur Rehman; Alswelmi, Farhan Khashim

    2017-01-01

    Objective: To evaluate the prevalence and causes of visual impairment (VI) among Saudi adults in Arar City, the capital of Northern Border Region of Saudi Arabia. Methods: This population-based cross-sectional study was conducted on 705 Saudi adults aged 18 years and older. All participants underwent ophthalmic examination including visual acuity (VA) testing, auto refraction, intraocular pressure (IOP) measurement and fundus examination. Results: In the present study 166 cases (23.5%) were found to have VI, while only 12 cases (1.7%) were considered as blind following the WHO definitions. Cataract was found to be the main cause of VI [51 cases (30.7%)] followed by refractive error (RE) [41 cases (24.7%)] and diabetic retinopathy (DR) [22 cases (13.2%)]. Seventy one cases of the studied subjects (10.07 %) had shown unilateral VI, while 13 cases (1.8%) had shown unilateral blindness with the other eye normal (VA ≥ 20/20). Conclusion: Visual impairment is highly prevalent among Saudi adults in Arar city. Cataract, refractive error and diabetic retinopathy are the main 3 leading causes. Better plans for diagnosis and treatment should be considered to decrease the magnitude of the problem. PMID:28367193

  14. Visual performance of adults with prelingual auditory impairment.

    PubMed

    Rietveld, Simon; Spiering, Mark; Rotteveel, Mark; van Beest, Ilja

    Reaction times and picture evaluations by 18 adults with hearing loss were compared with those of 18 matched controls during two visual priming tasks. In Task 1, participants reacted to sexual and plant target pictures (while influenced by similar preceding pictures) by pressing "sex" or "plant" buttons. In Task 2, they evaluated target Japanese ideographs (while influenced by preceding positive or negative facial expressions as prime pictures) by pressing "positive" or "negative" buttons. In Task 1, the controls had the faster responses. In Task 2, they showed the usual congruent priming effect during very short prime presentations. Participants with hearing loss showed this effect only during short and long prime presentation times; thus, they were not superior to the controls in picture recognition, instead showing (a) impaired processing of visual information or (b) impaired perceptual-motor skills regarding quick responses to visual information (or both).

  15. Auditory-visual speech perception in an adult with aphasia.

    PubMed

    Youse, Kathleen M; Cienkowski, Kathleen M; Coelho, Carl A

    2004-08-01

    The evaluation of auditory-visual speech perception is not typically undertaken in the assessment of aphasia; however, treatment approaches utilise bimodal presentations. Research demonstrates that auditory and visual information are integrated for speech perception. The strongest evidence of this cross-modal integration is the McGurk effect. This indirect measure of integration shows that presentation of conflicting tokens may change perception (e.g. auditory /bi/ + visual /gi/ = /di/). The purpose of this study was to investigate the ability of a person with mild aphasia to identify tokens presented in auditory-only, visual-only and auditory-visual conditions. It was hypothesized that performance would be best in the bimodal condition and that presence of the McGurk effect would demonstrate integration of speech information. Findings did not support the hypotheses. It is suspected that successful integration of AV speech information was limited by a perseverative response pattern. This case study suggests the use of bisensory speech information may be impaired in adults with aphasia.

  16. The effects of visual stimuli on EEG mu rhythms in healthy adults.

    PubMed

    Kim, JiYoung; Kim, SeongYoel

    2016-06-01

    [Purpose] Several action observation/imagery training studies have been conducted in patients with limited physical activity showing improvements in motor function. However, most studies compared effects of action observation and imagery, so little is known about the changes caused by subsequent observation of target objects. Moreover, few studies analyzed brain wave changes in the EEG mu rhythm. [Subjects and Methods] Eighteen healthy female adults participated in this study, and were divided into two groups: 'Visual Stimuli' and 'Non-Visual Stimuli'. EEG amplitude in the 8-13 Hz frequency band over the sensorimotor cortex was evaluated. [Results] Significant mu suppression was obtained in the action observation trials. Mu power showed a main effect of visual stimuli, with decreased power during action observation, and increased power post-observation in both conditions. Comparing the 'Visual Stimuli' and 'Non-Visual Stimuli' conditions during the post-observation period, mu power demonstrated a greater increase in the 'Non-Visual Stimuli' condition. Furthermore, mu power was lower post-observation than pre-observation. [Conclusion] These results show the effects of visual input between maintaining target objects and no visual input, and their relevance to modulations of the mirror neuron system. It also suggests that greater visual input may be more effective for cognitive rehabilitation.

  17. Relating Standardized Visual Perception Measures to Simulator Visual System Performance

    NASA Technical Reports Server (NTRS)

    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).

  18. Multiple Roles for Nogo Receptor 1 in Visual System Plasticity.

    PubMed

    Stephany, Céleste-Élise; Frantz, Michael G; McGee, Aaron W

    2016-12-01

    During the developmental critical period for visual plasticity, discordant vision alters the responsiveness of neurons in visual cortex. The subsequent closure of the critical period not only consolidates neural function but also limits recovery of acuity from preceding abnormal visual experience. Despite species-specific differences in circuitry of the visual system, these characteristics are conserved. The nogo-66 receptor 1 (ngr1) is one of only a small number of genes identified thus far that is essential to closing the critical period. Mice lacking a functional ngr1 gene retain developmental visual plasticity as adults and their visual acuity spontaneously improves after prolonged visual deprivation. Experiments employing conditional mouse genetics have revealed that ngr1 restricts plasticity within distinct circuits for ocular dominance and visual acuity. However, the mechanisms by which NgR1 limits plasticity have not been elucidated, in part because the subcellular localization and signal transduction of the protein are only partially understood. Here we explore potential mechanisms for NgR1 function in relation to manipulations that reactivate visual plasticity in adults and propose lines of investigation to address relevant gaps in knowledge.

  19. Conditions affecting beliefs about visual perception among children and adults.

    PubMed

    Winer, G A; Cottrell, J E; Karefilaki, K D; Chronister, M

    1996-03-01

    Children and adults were tested on their beliefs about whether visual processes involved intromissions (visual input) or extramissions (visual output) across a variety of situations. The idea that extramissions are part of the process of vision was first expressed by ancient philosophers, including Plato, Euclid, and Ptolemy and has been shown to be evident in children and in some adults. The present research showed that when questions about vision referred to luminous as opposed to non-luminous objects, under certain conditions there was some increase in intromission beliefs, but almost no corresponding decline in extramission beliefs, and no evidence of transfer of intromission responses to questions referring to nonluminous objects. A separate study showed that college students, but not children, increased their extramission responses to questions providing a positive emotional context. The results are inconsistent with the idea that simple experiences increase or reinforce a coherent theory of vision. The results also have implications for understanding the nature of beliefs about scientific processes and for education.

  20. Space shuttle visual simulation system design study

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The current and near-future state-of-the-art in visual simulation equipment technology is related to the requirements of the space shuttle visual system. Image source, image sensing, and displays are analyzed on a subsystem basis, and the principal conclusions are used in the formulation of a recommended baseline visual system. Perceptibility and visibility are also analyzed.

  1. Effective learner-centered strategies for teaching adults: using visual media to engage the adult learner.

    PubMed

    Myers, Dennis R; Sykes, Catherine; Myers, Scott

    2008-01-01

    This article offers practical guidance for educators as they prepare specialists to enhance the lives and communities of older persons through the strategic use of visual media in age-related courses. Advantages and disadvantages of this learning innovation are provided as well as seven approaches for enriching instruction. Resources are included for locating effective visual media, matching course content with video resources, determining fair use of copyrighted media, and inserting video clips into PowerPoint presentations. Strategies for accessing assistive services for implementing visual media in the classroom are also addressed. This article promotes the use of visual media for the purpose of enriching gerontological and geriatrics instruction for the adult learner.

  2. A Comparison of the Visual Attention Patterns of People with Aphasia and Adults without Neurological Conditions for Camera-Engaged and Task-Engaged Visual Scenes

    ERIC Educational Resources Information Center

    Thiessen, Amber; Beukelman, David; Hux, Karen; Longenecker, Maria

    2016-01-01

    Purpose: The purpose of the study was to compare the visual attention patterns of adults with aphasia and adults without neurological conditions when viewing visual scenes with 2 types of engagement. Method: Eye-tracking technology was used to measure the visual attention patterns of 10 adults with aphasia and 10 adults without neurological…

  3. Audio-Visual and Meaningful Semantic Context Enhancements in Older and Younger Adults

    PubMed Central

    Smayda, Kirsten E.; Van Engen, Kristin J.; Maddox, W. Todd; Chandrasekaran, Bharath

    2016-01-01

    Speech perception is critical to everyday life. Oftentimes noise can degrade a speech signal; however, because of the cues available to the listener, such as visual and semantic cues, noise rarely prevents conversations from continuing. The interaction of visual and semantic cues in aiding speech perception has been studied in young adults, but the extent to which these two cues interact for older adults has not been studied. To investigate the effect of visual and semantic cues on speech perception in older and younger adults, we recruited forty-five young adults (ages 18–35) and thirty-three older adults (ages 60–90) to participate in a speech perception task. Participants were presented with semantically meaningful and anomalous sentences in audio-only and audio-visual conditions. We hypothesized that young adults would outperform older adults across SNRs, modalities, and semantic contexts. In addition, we hypothesized that both young and older adults would receive a greater benefit from a semantically meaningful context in the audio-visual relative to audio-only modality. We predicted that young adults would receive greater visual benefit in semantically meaningful contexts relative to anomalous contexts. However, we predicted that older adults could receive a greater visual benefit in either semantically meaningful or anomalous contexts. Results suggested that in the most supportive context, that is, semantically meaningful sentences presented in the audiovisual modality, older adults performed similarly to young adults. In addition, both groups received the same amount of visual and meaningful benefit. Lastly, across groups, a semantically meaningful context provided more benefit in the audio-visual modality relative to the audio-only modality, and the presence of visual cues provided more benefit in semantically meaningful contexts relative to anomalous contexts. These results suggest that older adults can perceive speech as well as younger adults when

  4. Infant and adult visual attention during an imitation demonstration

    PubMed Central

    Taylor, Gemma; Herbert, Jane S

    2014-01-01

    Deferred imitation tasks have shown that manipulations at encoding can enhance infant learning and memory performance within an age, suggesting that brain maturation alone cannot fully account for all developmental changes in early memory abilities. The present study investigated whether changes in the focus of attention during learning might contribute to improving memory abilities during infancy. Infants aged 6, 9, and 12 months, and an adult comparison group, watched a video of a puppet imitation demonstration while visual behavior was recorded on an eye tracker. Overall, infants spent less time attending to the video than adults, and distributed their gaze more equally across the demonstrator and puppet stimulus. In contrast, adults directed their gaze primarily to the puppet. When infants were tested for their behavioral recall of the target actions, “imitators” were shown to have increased attention to the person and decreased attention to the background compared to “non-imitators.” These results suggest that attention during learning is related to memory outcome and that changes in attention may be one mechanism by which manipulations to the learning event may enhance infant recall memory. © 2013 The Authors. Developmental Psychobiology published by Wiley Periodicals, Inc. PMID:24037972

  5. Visual system manifestations of Alzheimer's disease.

    PubMed

    Kusne, Yael; Wolf, Andrew B; Townley, Kate; Conway, Mandi; Peyman, Gholam A

    2016-11-19

    Alzheimer's disease (AD) is an increasingly common disease with massive personal and economic costs. While it has long been known that AD impacts the visual system, there has recently been an increased focus on understanding both pathophysiological mechanisms that may be shared between the eye and brain and how related biomarkers could be useful for AD diagnosis. Here, were review pertinent cellular and molecular mechanisms of AD pathophysiology, the presence of AD pathology in the visual system, associated functional changes, and potential development of diagnostic tools based on the visual system. Additionally, we discuss links between AD and visual disorders, including possible pathophysiological mechanisms and their relevance for improving our understanding of AD.

  6. Influence of aging on visual perception and visual motor integration in Korean adults.

    PubMed

    Kim, Eunhwi; Park, Young-Kyung; Byun, Yong-Hyun; Park, Mi-Sook; Kim, Hong

    2014-08-01

    This study investigated age-related changes of cognitive function in Korean adults using the Korean-Developmental Test of Visual Perception-2 (K-DTVP-2) and the Visual Motor Integration-3rd Revision (VMI-3R) test, and determined the main factors influencing VP and VMI in older adults. For this research, 139 adults for the K-DTVP-2 and 192 adults for the VMI-3R, from a total of 283 participants, were randomly and separately recruited in province, Korea. The present study showed that the mean score of the K-DTVP-2 and VMI-3R in 10-yr age increments significantly decreased as age increased (K-DTVP-2, F= 41.120, P< 0.001; VMI-3R, F= 16.583, P< 0.001). The mean score of the VMI-3R and K-DTVP-2 were significantly decreased in participants in their 50s compared to those in their 20s (P< 0.05). Age (t= -9.130, P< 0.001), gender (t= 3.029, P= 0.003), and the presence of diseases (t= -2.504, P= 0.013) were the significant factors affecting K-DTVP-2 score. On the other hand, age (t= -6.300, P< 0.001) was the only significant factor affecting VMI-3R score. K-DTVP-2 score (Standardized β= -0.611) decreased more sensitively with aging than VMI-3R (Standardized β= -0.467). The two measurements had a significant positive correlation (r = 0.855, P< 0.001). In conclusion, it can be suggested that VP and VMI should be regularly checked from an individual's 50s, which is a critical period for detecting cognitive decline by aging. Both the K-DTVP-2 and VMI-3R could be used for determining the level of cognitive deficit by aging.

  7. Cortical responses from adults and infants to complex visual stimuli.

    PubMed

    Schulman-Galambos, C; Galambos, R

    1978-10-01

    Event-related potentials (ERPs) time-locked to the onset of visual stimuli were extracted from the EEG of normal adult (N = 16) and infant (N = 23) subjects. Subjects were not required to make any response. Stimuli delivered to the adults were 150 msec exposures of 2 sets of colored slides projected in 4 blocks, 2 in focus and 2 out of focus. Infants received 2-sec exposures of slides showing people, colored drawings or scenes from Disneyland, as well as 2-sec illuminations of the experimenter as she played a game or of a TV screen the baby was watching. The adult ERPs showed 6 waves (N1 through P4) in the 140--600-msec range; this included a positive wave at around 350 msec that was large when the stimuli were focused and smaller when they were not. The waves in the 150--200-msec range, by contrast, steadily dropped in amplitude as the experiment progressed. The infant ERPs differed greatly from the adult ones in morphology, usually showing a positive (latency about 200 msec)--negative(5--600msec)--positive(1000msec) sequence. This ERP appeared in all the stimulus conditions; its presence or absence, furthermore, was correlated with whether or not the baby seemed interested in the stimuli. Four infants failed to produce these ERPs; an independent measure of attention to the stimuli, heart rate deceleration, was demonstrated in two of them. An electrode placed beneath the eye to monitor eye movements yielded ERPs closely resembling those derived from the scalp in most subjects; reasons are given for assigning this response to activity in the brain, probably at the frontal pole. This study appears to be one of the first to search for cognitive 'late waves' in a no-task situation. The results suggest that further work with such task-free paradigms may yield additional useful techniques for studying the ERP.

  8. Art, Illusion and the Visual System.

    ERIC Educational Resources Information Center

    Livingstone, Margaret S.

    1988-01-01

    Describes the three part system of human vision. Explores the anatomical arrangement of the vision system from the eyes to the brain. Traces the path of various visual signals to their interpretations by the brain. Discusses human visual perception and its implications in art and design. (CW)

  9. Why do pictures, but not visual words, reduce older adults' false memories?

    PubMed

    Smith, Rebekah E; Hunt, R Reed; Dunlap, Kathryn R

    2015-09-01

    Prior work shows that false memories resulting from the study of associatively related lists are reduced for both young and older adults when the auditory presentation of study list words is accompanied by related pictures relative to when auditory word presentation is combined with visual presentation of the word. In contrast, young adults, but not older adults, show a reduction in false memories when presented with the visual word along with the auditory word relative to hearing the word only. In both cases of pictures relative to visual words and visual words relative to auditory words alone, the benefit of picture and visual words in reducing false memories has been explained in terms of monitoring for perceptual information. In our first experiment, we provide the first simultaneous comparison of all 3 study presentation modalities (auditory only, auditory plus visual word, and auditory plus picture). Young and older adults show a reduction in false memories in the auditory plus picture condition, but only young adults show a reduction in the visual word condition relative to the auditory only condition. A second experiment investigates whether older adults fail to show a reduction in false memory in the visual word condition because they do not encode perceptual information in the visual word condition. In addition, the second experiment provides evidence that the failure of older adults to show the benefits of visual word presentation is related to reduced cognitive resources. (PsycINFO Database Record

  10. Improving the legibility of prescription medication labels for older adults and adults with visual impairment

    PubMed Central

    Leat, Susan J.; Krishnamoorthy, Abinaya; Carbonara, Antonio; Gold, Deborah; Rojas-Fernandez, Carlos

    2016-01-01

    Objectives: Most current prescription labels fail to meet print guidelines, especially in print size. We therefore compared the legibility of current prescription medication labels against the legibility of prototype labels, based on current guidelines for legibility. Method: Sample medication labels were obtained from pharmacies, and prototype medication labels were developed according to legibility guidelines from nongovernmental organizations and pharmacy organizations. Three groups of participants, consisting of older adults with normal vision, older adults with visual impairment and younger adults with visual impairment (total N = 71) took part. Participants were asked to read and rank the labels. Reading speed and accuracy were determined. Results: Accuracies were high (75%–100%), and there were no significant differences between samples or prototypes or between groups. Prototypes, however, were read faster than samples (p < 0.001). Subjectively, participants preferred the largest print option (p < 0.001) and instructions with the numbers written in highlighted uppercase words (p < 0.001). Discussion: The results indicate that improvements to the label would include larger print size, a consistent layout with left justification and using upper case with highlighting for emphasis of the numbers in the instructions. PMID:27212968

  11. Physical Activity, Body Composition, and Perceived Quality of Life of Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Holbrook, Elizabeth A.; Caputo, Jennifer L.; Perry, Tara L.; Fuller, Dana K.; Morgan, Don W.

    2009-01-01

    Relatively little is known about the health and fitness of adults with visual impairments. This article documents the physical activity levels and body-composition profiles of young and middle-aged adults with visual impairments and addresses the concomitant effects of these factors on perceived quality of life. (Contains 2 tables.)

  12. Sexual Activity of Young Adults Who Are Visually Impaired and the Need for Effective Sex Education

    ERIC Educational Resources Information Center

    Kelly, Stacy M.; Kapperman, Gaylen

    2012-01-01

    Introduction: Little research has been reported on all aspects of sexuality as it pertains to individuals with visual impairments. This article analyzes data on the sexual experiences of young adults who are visually impaired and young adults without disabilities. Methods: The authors conducted a secondary analysis of the National Longitudinal…

  13. Change in Quality of Life after Rehabilitation: Prognostic Factors for Visually Impaired Adults

    ERIC Educational Resources Information Center

    Langelaan, Maaike; de Boer, Michiel R.; van Nispen, Ruth M. A.; Wouters, Bill; Moll, Annette C.; van Rens, Ger H. M. B.

    2009-01-01

    The overall aim of rehabilitation for visually impaired adults is to improve the quality of life and (societal) participation. The objectives of this study were to obtain the short-term and long-term outcome of a comprehensive rehabilitation programme on quality of life for visually impaired adults, and prognostic baseline factors responsible for…

  14. Consumers' Perspectives on Effective Orientation and Mobility Services for Diabetic Adults Who Are Visually Impaired

    ERIC Educational Resources Information Center

    Griffin-Shirley, Nora; Kelley, Pat; Matlock, Dwayne; Page, Anita

    2006-01-01

    The authors interviewed and videotaped diabetic adults with visual impairments about their perceptions of orientation and mobility (O&M) services that they had received. The visual impairments of these middle-aged adults ranged from totally blind to low vision. The interview questions focused on demographic information about the interviewees, the…

  15. Designing a visualization system for hydrological data

    NASA Astrophysics Data System (ADS)

    Fuhrmann, Sven

    2000-02-01

    The field of hydrology is, as any other scientific field, strongly affected by a massive technological evolution. The spread of modern information and communication technology within the last three decades has led to an increased collection, availability and use of spatial and temporal digital hydrological data. In a two-year research period a working group in Muenster applied and developed methods for the visualization of digital hydrological data and the documentation of hydrological models. A low-cost multimedial, hydrological visualization system (HydroVIS) for the Weser river catchment was developed. The research group designed HydroVIS under freeware constraints and tried to show what kind of multimedia visualization techniques can be effectively used with a nonprofit hydrological visualization system. The system's visual components include features such as electronic maps, temporal and nontemporal cartographic animations, the display of geologic profiles, interactive diagrams and hypertext, including photographs and tables.

  16. Characteristics of flight simulator visual systems

    NASA Technical Reports Server (NTRS)

    Statler, I. C. (Editor)

    1981-01-01

    The physical parameters of the flight simulator visual system that characterize the system and determine its fidelity are identified and defined. The characteristics of visual simulation systems are discussed in terms of the basic categories of spatial, energy, and temporal properties corresponding to the three fundamental quantities of length, mass, and time. Each of these parameters are further addressed in relation to its effect, its appropriate units or descriptors, methods of measurement, and its use or importance to image quality.

  17. Project DyAdd: Visual Attention in Adult Dyslexia and ADHD

    ERIC Educational Resources Information Center

    Laasonen, Marja; Salomaa, Jonna; Cousineau, Denis; Leppamaki, Sami; Tani, Pekka; Hokkanen, Laura; Dye, Matthew

    2012-01-01

    In this study of the project DyAdd, three aspects of visual attention were investigated in adults (18-55 years) with dyslexia (n = 35) or attention deficit/hyperactivity disorder (ADHD, n = 22), and in healthy controls (n = 35). Temporal characteristics of visual attention were assessed with Attentional Blink (AB), capacity of visual attention…

  18. Visual acuity measured with luminance-modulated and contrast-modulated noise letter stimuli in young adults and adults above 50 years old

    PubMed Central

    Woi, Pui Juan; Kaur, Sharanjeet; Waugh, Sarah J.; Hairol, Mohd Izzuddin

    2016-01-01

    The human visual system is sensitive in detecting objects that have different luminance level from their background, known as first-order or luminance-modulated (LM) stimuli. We are also able to detect objects that have the same mean luminance as their background, only differing in contrast (or other attributes). Such objects are known as second-order or contrast-modulated (CM), stimuli. CM stimuli are thought to be processed in higher visual areas compared to LM stimuli, and may be more susceptible to ageing. We compared visual acuities (VA) of five healthy older adults (54.0±1.83 years old) and five healthy younger adults (25.4±1.29 years old) with LM and CM letters under monocular and binocular viewing. For monocular viewing, age had no effect on VA [F(1, 8)= 2.50, p> 0.05]. However, there was a significant main effect of age on VA under binocular viewing [F(1, 8)= 5.67, p< 0.05].  Binocular VA with CM letters in younger adults was approximately two lines better than that in older adults. For LM, binocular summation ratios were similar for older (1.16±0.21) and younger (1.15±0.06) adults. For CM, younger adults had higher binocular summation ratio (1.39±0.08) compared to older adults (1.12±0.09). Binocular viewing improved VA with LM letters for both groups similarly. However, in older adults, binocular viewing did not improve VA with CM letters as much as in younger adults. This could reflect a decline of higher visual areas due to ageing process, most likely higher than V1, which may be missed if measured with luminance-based stimuli alone. PMID:28184281

  19. Visual acuity measured with luminance-modulated and contrast-modulated noise letter stimuli in young adults and adults above 50 years old.

    PubMed

    Woi, Pui Juan; Kaur, Sharanjeet; Waugh, Sarah J; Hairol, Mohd Izzuddin

    2016-01-01

    The human visual system is sensitive in detecting objects that have different luminance level from their background, known as first-order or luminance-modulated (LM) stimuli. We are also able to detect objects that have the same mean luminance as their background, only differing in contrast (or other attributes). Such objects are known as second-order or contrast-modulated (CM), stimuli. CM stimuli are thought to be processed in higher visual areas compared to LM stimuli, and may be more susceptible to ageing. We compared visual acuities (VA) of five healthy older adults (54.0±1.83 years old) and five healthy younger adults (25.4±1.29 years old) with LM and CM letters under monocular and binocular viewing. For monocular viewing, age had no effect on VA [F(1, 8)= 2.50, p> 0.05]. However, there was a significant main effect of age on VA under binocular viewing [F(1, 8)= 5.67, p< 0.05].  Binocular VA with CM letters in younger adults was approximately two lines better than that in older adults. For LM, binocular summation ratios were similar for older (1.16±0.21) and younger (1.15±0.06) adults. For CM, younger adults had higher binocular summation ratio (1.39±0.08) compared to older adults (1.12±0.09). Binocular viewing improved VA with LM letters for both groups similarly. However, in older adults, binocular viewing did not improve VA with CM letters as much as in younger adults. This could reflect a decline of higher visual areas due to ageing process, most likely higher than V1, which may be missed if measured with luminance-based stimuli alone.

  20. An interpersonal multimedia visualization system

    SciTech Connect

    Phillips, R.L.

    1990-01-01

    Media View is a computer program that provides a generic infrastructure for authoring and interacting with multimedia documents. Among its many applications is the ability to furnish a user with a comprehensive environment for analysis and visualization. With MediaView the user produces a document'' that contains mathematics, datasets and associated visualizations. From the dataset or embedded mathematics animated sequences can be produced in situ. The mathematical content of the document'' can be explored through manipulation with Mathematica {trademark}. Since the document'' is all digital, it can be shared with a co-worker on a local network or mailed electronically to a colleague at a distant site. Animations and any other substructure of the document'' persist through the mailing process and can be awakened at the destination by the recipient. 5 refs., 4 figs.

  1. A Semi-Persistent Adult Ocular Dominance Plasticity in Visual Cortex Is Stabilized by Activated CREB

    ERIC Educational Resources Information Center

    Barco, Angel; Kandel, Eric R.; Gordon, Barbara; Lickey, Marvin E.; Suzuki, Seigo; Pham, Tony A.; Graham, Sarah J.

    2004-01-01

    The adult cerebral cortex can adapt to environmental change. Using monocular deprivation as a paradigm, we find that rapid experience-dependent plasticity exists even in the mature primary visual cortex. However, adult cortical plasticity differs from developmental plasticity in two important ways. First, the effect of adult, but not juvenile…

  2. Interaction between the oculomotor and postural systems during a dual-task: Compensatory reductions in head sway following visually-induced postural perturbations promote the production of accurate double-step saccades in standing human adults.

    PubMed

    Boulanger, Mathieu; Giraudet, Guillaume; Faubert, Jocelyn

    2017-01-01

    Humans routinely scan their environment for useful information using saccadic eye movements and/or coordinated movements of the eyes and other body segments such the head and the torso. Most previous eye movement studies were conducted with seated subject and showed that single saccades and sequences of saccades (e.g. double-step saccades) made to briefly flashed stimuli were equally accurate and precise. As one can easily appreciate, most gaze shifts performed daily by a given person are not produced from a seated position, but rather from a standing position either as subjects perform an action from an upright stance or as they walk from one place to another. In the experiments presented here, we developed a new dual-task paradigm in order to study the interaction between the gaze control system and the postural system. Healthy adults (n = 12) were required to both maintain balance and produce accurate single-step and double-step eye saccades from a standing position. Visually-induced changes in head sway were evoked using wide-field background stimuli that either moved in the mediolateral direction or in the anteroposterior direction. We found that, as in the seated condition, single- and double-step saccades were very precise and accurate when made from a standing position, but that a tighter control of head sway was necessary in the more complex double-step saccades condition for equivalent results to be obtained. Our perturbation results support the "common goal" hypothesis that state that if necessary, as was the case during the more complex oculomotor task, context-dependent modulations of the postural system can be triggered to reduced instability and therefore support the accomplishment of a suprapostural goal.

  3. Interaction between the oculomotor and postural systems during a dual-task: Compensatory reductions in head sway following visually-induced postural perturbations promote the production of accurate double-step saccades in standing human adults

    PubMed Central

    Giraudet, Guillaume; Faubert, Jocelyn

    2017-01-01

    Humans routinely scan their environment for useful information using saccadic eye movements and/or coordinated movements of the eyes and other body segments such the head and the torso. Most previous eye movement studies were conducted with seated subject and showed that single saccades and sequences of saccades (e.g. double-step saccades) made to briefly flashed stimuli were equally accurate and precise. As one can easily appreciate, most gaze shifts performed daily by a given person are not produced from a seated position, but rather from a standing position either as subjects perform an action from an upright stance or as they walk from one place to another. In the experiments presented here, we developed a new dual-task paradigm in order to study the interaction between the gaze control system and the postural system. Healthy adults (n = 12) were required to both maintain balance and produce accurate single-step and double-step eye saccades from a standing position. Visually-induced changes in head sway were evoked using wide-field background stimuli that either moved in the mediolateral direction or in the anteroposterior direction. We found that, as in the seated condition, single- and double-step saccades were very precise and accurate when made from a standing position, but that a tighter control of head sway was necessary in the more complex double-step saccades condition for equivalent results to be obtained. Our perturbation results support the “common goal” hypothesis that state that if necessary, as was the case during the more complex oculomotor task, context-dependent modulations of the postural system can be triggered to reduced instability and therefore support the accomplishment of a suprapostural goal. PMID:28296958

  4. Using Visualization in Cockpit Decision Support Systems

    SciTech Connect

    Aragon, Cecilia R.

    2005-07-01

    In order to safely operate their aircraft, pilots must makerapid decisions based on integrating and processing large amounts ofheterogeneous information. Visual displays are often the most efficientmethod of presenting safety-critical data to pilots in real time.However, care must be taken to ensure the pilot is provided with theappropriate amount of information to make effective decisions and notbecome cognitively overloaded. The results of two usability studies of aprototype airflow hazard visualization cockpit decision support systemare summarized. The studies demonstrate that such a system significantlyimproves the performance of helicopter pilots landing under turbulentconditions. Based on these results, design principles and implicationsfor cockpit decision support systems using visualization arepresented.

  5. Visualizing Mobility of Public Transportation System.

    PubMed

    Zeng, Wei; Fu, Chi-Wing; Arisona, Stefan Müller; Erath, Alexander; Qu, Huamin

    2014-12-01

    Public transportation systems (PTSs) play an important role in modern cities, providing shared/massive transportation services that are essential for the general public. However, due to their increasing complexity, designing effective methods to visualize and explore PTS is highly challenging. Most existing techniques employ network visualization methods and focus on showing the network topology across stops while ignoring various mobility-related factors such as riding time, transfer time, waiting time, and round-the-clock patterns. This work aims to visualize and explore passenger mobility in a PTS with a family of analytical tasks based on inputs from transportation researchers. After exploring different design alternatives, we come up with an integrated solution with three visualization modules: isochrone map view for geographical information, isotime flow map view for effective temporal information comparison and manipulation, and OD-pair journey view for detailed visual analysis of mobility factors along routes between specific origin-destination pairs. The isotime flow map linearizes a flow map into a parallel isoline representation, maximizing the visualization of mobility information along the horizontal time axis while presenting clear and smooth pathways from origin to destinations. Moreover, we devise several interactive visual query methods for users to easily explore the dynamics of PTS mobility over space and time. Lastly, we also construct a PTS mobility model from millions of real passenger trajectories, and evaluate our visualization techniques with assorted case studies with the transportation researchers.

  6. Multiplane binocular visual display system

    NASA Technical Reports Server (NTRS)

    Chase, W. D.

    1976-01-01

    Electro-optic system is interfaced with digital computer in flight simulator to generate simultaneous multiple-image planes in real time. System may have applications with other display and remote-control systems.

  7. Visual computing model for immune system and medical system.

    PubMed

    Gong, Tao; Cao, Xinxue; Xiong, Qin

    2015-01-01

    Natural immune system is an intelligent self-organizing and adaptive system, which has a variety of immune cells with different types of immune mechanisms. The mutual cooperation between the immune cells shows the intelligence of this immune system, and modeling this immune system has an important significance in medical science and engineering. In order to build a comprehensible model of this immune system for better understanding with the visualization method than the traditional mathematic model, a visual computing model of this immune system was proposed and also used to design a medical system with the immune system, in this paper. Some visual simulations of the immune system were made to test the visual effect. The experimental results of the simulations show that the visual modeling approach can provide a more effective way for analyzing this immune system than only the traditional mathematic equations.

  8. The visual system of the guitar fish (Rhinobatos productus).

    PubMed

    Ebbesson, S O; Meyer, D L

    1980-01-01

    The retinal projections in adult and juvenile guitar fish (Rhinobatos productus) were determined with the aid of the Nauta-Fink-Heimer techniques. The visual system was found to be more extensive and more differentiated than in any other elasmobranch studied to date. Massive projections exist to the dorsal and ventral thalamus, tectum and pretectum, in addition to the usual weak contributions to the hypothalamus and the ventral mesencephalic tegmentum. The projection to the lateral tectum is significantly less distinct than that to the medial part of this structure, suggesting that the ventral visual field has a smaller input, perhaps due to the fact that this visual field is normally aimed at the body of this flat fish.

  9. Earth orbital teleoperator visual system evaluation program

    NASA Technical Reports Server (NTRS)

    Shields, N. L., Jr.; Kirkpatrick, M., III; Frederick, P. N.; Malone, T. B.

    1975-01-01

    Empirical tests of range estimation accuracy and resolution, via television, under monoptic and steroptic viewing conditions are discussed. Test data are used to derive man machine interface requirements and make design decisions for an orbital remote manipulator system. Remote manipulator system visual tasks are given and the effects of system parameters of these tasks are evaluated.

  10. Relationships between global motion and global form processing, practice, cognitive and visual processing in adults with dyslexia or visual discomfort.

    PubMed

    Conlon, Elizabeth G; Sanders, Mary A; Wright, Craig M

    2009-02-01

    The aim of the first of two experiments was to investigate the effect of practice on sensitivity to global motion and global form in a group of adults with dyslexia, a group of normal readers with visual discomfort, a group with dyslexia and visual discomfort, and a control group. In comparison to the control group, and regardless of the effect of practice, the group with dyslexia was significantly less sensitive to global motion. No differences in global motion sensitivity were found when individuals with dyslexia, with or without visual discomfort, were compared. The normal reading group with visual discomfort was less sensitive to global motion than the control group at baseline, but not when a second estimate of motion sensitivity was obtained. About 30% of the group with dyslexia had a global motion deficit on each threshold estimate. In contrast, there were no significant effects of practice or group on sensitivity to global form. In Experiment 2, performance on a number of cognitive and visual processing tasks was measured in four groups: two with dyslexia; one with and one without a global motion deficit, a normal reading group with visual discomfort, and a control group. The group with visual discomfort had reduced visual processing speed only. Regardless of whether a global motion processing deficit was present or absent in individuals with dyslexia, reduced accuracy was found on the language and visual processing measures, and on a rapid temporal sequencing task. Individuals with dyslexia and a global motion deficit had poorer accuracy than individuals with dyslexia and no motion deficit on the phonological processing and verbal short term memory tasks. We concluded that some adults with dyslexia have a persistent deficit when processing global motion but not global form. This is consistent with reports of a magnocellular pathway deficit in this group. Individuals with visual discomfort do not have a magnocellular processing deficit, but have perceptual

  11. Sex differences in the human visual system.

    PubMed

    Vanston, John E; Strother, Lars

    2017-01-02

    This Mini-Review summarizes a wide range of sex differences in the human visual system, with a primary focus on sex differences in visual perception and its neural basis. We highlight sex differences in both basic and high-level visual processing, with evidence from behavioral, neurophysiological, and neuroimaging studies. We argue that sex differences in human visual processing, no matter how small or subtle, support the view that females and males truly see the world differently. We acknowledge some of the controversy regarding sex differences in human vision and propose that such controversy should be interpreted as a source of motivation for continued efforts to assess the validity and reliability of published sex differences and for continued research on sex differences in human vision and the nervous system in general. © 2016 Wiley Periodicals, Inc.

  12. The Components of the Visual System of a Dragonfly

    PubMed Central

    Ruck, Philip

    1965-01-01

    In this study of the electroretinograms of dragonflies (adults and nymphs) the objectives were to determine the number of classes of photoreceptors present in the visual system and to allocate these to particular morphological regions. There are probably five classes of photoreceptors present with peak sensitivities near 550, 530, 518, 420, and < 380 mµ. The dorsal ocelli contain two classes (518 mµ and < 380 mµ). The ventral (anterior) ommatidia of the adult compound eye contain at least two classes (near 518 mµ and < 380 mµ) and probably a third class (near 550 mµ). The dorsal ommatidia of the adult compound eye contain one class (420 mµ) and possibly another class (< 380 mµ). The compound eye of the nymph contains one class (530 mµ) and possibly another class (420 mµ). PMID:19873565

  13. Visual system for waste tank cleanup

    SciTech Connect

    Millsap, W.J. ); Shimamoto, M.S.; Spain, E.H.; Smith, D.C. ); Evans, M.S. )

    1991-09-01

    The single-shell underground radioactive waste storage tanks at the US Department of Energy's Hanford Site are briefly described and their physical complexities discussed. The attributes of a remote visual system needed to work productively in this environment are reviewed. The vision subsystem of the Naval Ocean Systems Center's TeleOperator/telePresence System, which closely approaches the required attributes, is briefly described. The possibility and usefulness of overlaying the visual image of the tank and its contents with a virtual model are discussed.

  14. Visual system for waste tank cleanup

    SciTech Connect

    Millsap, W.J.; Shimamoto, M.S.; Spain, E.H.; Smith, D.C.; Evans, M.S.

    1991-09-01

    The single-shell underground radioactive waste storage tanks at the US Department of Energy`s Hanford Site are briefly described and their physical complexities discussed. The attributes of a remote visual system needed to work productively in this environment are reviewed. The vision subsystem of the Naval Ocean Systems Center`s TeleOperator/telePresence System, which closely approaches the required attributes, is briefly described. The possibility and usefulness of overlaying the visual image of the tank and its contents with a virtual model are discussed.

  15. The visual system of male scale insects.

    PubMed

    Buschbeck, Elke K; Hauser, Martin

    2009-03-01

    Animal eyes generally fall into two categories: (1) their photoreceptive array is convex, as is typical for camera eyes, including the human eye, or (2) their photoreceptive array is concave, as is typical for the compound eye of insects. There are a few rare examples of the latter eye type having secondarily evolved into the former one. When viewed in a phylogenetic framework, the head morphology of a variety of male scale insects suggests that this group could be one such example. In the Margarodidae (Hemiptera, Coccoidea), males have been described as having compound eyes, while males of some more derived groups only have two single-chamber eyes on each side of the head. Those eyes are situated in the place occupied by the compound eye of other insects. Since male scale insects tend to be rare, little is known about how their visual systems are organized, and what anatomical traits are associated with this evolutionary transition. In adult male Margarodidae, one single-chamber eye (stemmateran ocellus) is present in addition to a compound eye-like region. Our histological investigation reveals that the stemmateran ocellus has an extended retina which is formed by concrete clusters of receptor cells that connect to its own first-order neuropil. In addition, we find that the ommatidia of the compound eyes also share several anatomical characteristics with simple camera eyes. These include shallow units with extended retinas, each of which is connected by its own small nerve to the lamina. These anatomical changes suggest that the margarodid compound eye represents a transitional form to the giant unicornal eyes that have been described in more derived species.

  16. The visual system of male scale insects

    NASA Astrophysics Data System (ADS)

    Buschbeck, Elke K.; Hauser, Martin

    2009-03-01

    Animal eyes generally fall into two categories: (1) their photoreceptive array is convex, as is typical for camera eyes, including the human eye, or (2) their photoreceptive array is concave, as is typical for the compound eye of insects. There are a few rare examples of the latter eye type having secondarily evolved into the former one. When viewed in a phylogenetic framework, the head morphology of a variety of male scale insects suggests that this group could be one such example. In the Margarodidae (Hemiptera, Coccoidea), males have been described as having compound eyes, while males of some more derived groups only have two single-chamber eyes on each side of the head. Those eyes are situated in the place occupied by the compound eye of other insects. Since male scale insects tend to be rare, little is known about how their visual systems are organized, and what anatomical traits are associated with this evolutionary transition. In adult male Margarodidae, one single-chamber eye (stemmateran ocellus) is present in addition to a compound eye-like region. Our histological investigation reveals that the stemmateran ocellus has an extended retina which is formed by concrete clusters of receptor cells that connect to its own first-order neuropil. In addition, we find that the ommatidia of the compound eyes also share several anatomical characteristics with simple camera eyes. These include shallow units with extended retinas, each of which is connected by its own small nerve to the lamina. These anatomical changes suggest that the margarodid compound eye represents a transitional form to the giant unicornal eyes that have been described in more derived species.

  17. Thematic World Wide Web Visualization System

    SciTech Connect

    1996-10-10

    WebTheme is a system designed to facilitate world wide web information access and retrieval through visualization. It consists of two principal pieces, a WebTheme Server which allows users to enter in a query and automatocally harvest and process information of interest, and a WebTheme browser, which allows users to work with both Galaxies and Themescape visualizations of their data within a JAVA capable world wide web browser. WebTheme is an Internet solution, meaning that access to the server and the resulting visualizations can all be performed through the use of a WWW browser. This allows users to access and interact with SPIRE (Spatial Paradigm for Information Retrieval and Exploration) based visualizations through a web browser regardless of what computer platforms they are running on. WebTheme is specifically designed to create databases by harvesting and processing WWW home pages available on the Internet.

  18. Earth orbital teleoperator visual system evaluation program

    NASA Technical Reports Server (NTRS)

    Frederick, P. N.; Shields, N. L., Jr.; Kirkpatrick, M., III

    1977-01-01

    Visual system parameters and stereoptic television component geometries were evaluated for optimum viewing. The accuracy of operator range estimation using a Fresnell stereo television system with a three dimensional cursor was examined. An operator's ability to align three dimensional targets using vidicon tube and solid state television cameras as part of a Fresnell stereoptic system was evaluated. An operator's ability to discriminate between varied color samples viewed with a color television system was determined.

  19. Using Visualization in Cockpit Decision Support Systems

    NASA Technical Reports Server (NTRS)

    Aragon, Cecilia R.

    2005-01-01

    In order to safely operate their aircraft, pilots must make rapid decisions based on integrating and processing large amounts of heterogeneous information. Visual displays are often the most efficient method of presenting safety-critical data to pilots in real time. However, care must be taken to ensure the pilot is provided with the appropriate amount of information to make effective decisions and not become cognitively overloaded. The results of two usability studies of a prototype airflow hazard visualization cockpit decision support system are summarized. The studies demonstrate that such a system significantly improves the performance of helicopter pilots landing under turbulent conditions. Based on these results, design principles and implications for cockpit decision support systems using visualization are presented.

  20. Processing of visual information compromises the ability of older adults to control novel fine motor tasks.

    PubMed

    Baweja, Harsimran S; Kwon, MinHyuk; Onushko, Tanya; Wright, David L; Corcos, Daniel M; Christou, Evangelos A

    2015-12-01

    We performed two experiments to determine whether amplified motor output variability and compromised processing of visual information in older adults impair short-term adaptations when learning novel fine motor tasks. In Experiment 1, 12 young and 12 older adults underwent training to learn how to accurately trace a sinusoidal position target with abduction-adduction of their index finger. They performed 48 trials, which included 8 blocks of 6 trials (the last trial of each block was performed without visual feedback). Afterward, subjects received an interference task (watched a movie) for 60 min. We tested retention by asking subjects to perform the sinusoidal task (5 trials) with and without visual feedback. In Experiment 2, 12 young and 10 older adults traced the same sinusoidal position target with their index finger and ankle at three distinct visual angles (0.25°, 1° and 5.4°). In Experiment 1, the movement error and variability were greater for older adults during the visual feedback trials when compared with young adults. In contrast, during the no-vision trials, age-associated differences in movement error and variability were ameliorated. Short-term adaptations in learning the sinusoidal task were similar for young and older adults. In Experiment 2, lower amount of visual feedback minimized the age-associated differences in movement variability for both the index finger and ankle movements. We demonstrate that although short-term adaptations are similar for young and older adults, older adults do not process visual information as well as young adults and that compromises their ability to control novel fine motor tasks during acquisition, which could influence long-term retention and transfer.

  1. The impact of visual distraction on episodic retrieval in older adults.

    PubMed

    Wais, Peter E; Martin, Grant M; Gazzaley, Adam

    2012-01-09

    Impairment in long-term memory is one of the most salient alterations in cognitive aging. Findings of age-related deficits in source monitoring and recollection have revealed a selective decline in memory for detailed information. The underlying mechanism of this phenomenon is not well understood. We hypothesized that the influence of task-irrelevant visual stimuli present in our environment interferes with retrieval of detailed memories more for older than younger adults. We compared memory performance on a recall test for visual details when older adult participants' eyes were closed versus performance when their eyes were open and irrelevant visual stimuli were presented. The results showed that the presence of irrelevant visual information diminished long-term memory performance based on an objective measure of recollection for visual details. Comparison of the current results to findings from our earlier study using the same experimental paradigm with younger adults revealed that visual distraction disrupted recollection of relevant details to a greater degree in older than younger adults. This result suggests that visual distraction overwhelms older adults' declining cognitive control resources that are instrumental in the retrieval and selection of mnemonic details. More generally, these findings explicate a mechanistic basis for selective impairment of recollection in normal aging.

  2. Auditory-Visual Speech Integration by Adults with and without Language-Learning Disabilities

    ERIC Educational Resources Information Center

    Norrix, Linda W.; Plante, Elena; Vance, Rebecca

    2006-01-01

    Auditory and auditory-visual (AV) speech perception skills were examined in adults with and without language-learning disabilities (LLD). The AV stimuli consisted of congruent consonant-vowel syllables (auditory and visual syllables matched in terms of syllable being produced) and incongruent McGurk syllables (auditory syllable differed from…

  3. Performing Movement Sequences with Knowledge of Results under Different Visual Conditions in Adults with Down Syndrome.

    ERIC Educational Resources Information Center

    Virji-Babul, Naznin; Lloyd, Jennifer E. V.; Van Gyn, Geraldine

    2003-01-01

    This study examined the learning of movement sequences in 10 adults with Down syndrome (DS) under two visual information conditions. Although DS individuals were significantly slower than neurologically typical participants, mean reaction and movement times were not affected by the visual information condition in either group. DS individuals…

  4. Mechanisms of recovery of visual function in adult amblyopia through a tailored action video game

    PubMed Central

    Vedamurthy, Indu; Nahum, Mor; Bavelier, Daphne; Levi, Dennis M.

    2015-01-01

    Amblyopia is a deficit in vision that arises from abnormal visual experience early in life. It was long thought to develop into a permanent deficit, unless properly treated before the end of the sensitive period for visual recovery. However, a number of studies now suggest that adults with long-standing amblyopia may at least partially recover visual acuity and stereopsis following perceptual training. Eliminating or reducing interocular suppression has been hypothesized to be at the root of these changes. Here we show that playing a novel dichoptic video game indeed results in reduced suppression, improved visual acuity and, in some cases, improved stereopsis. Our relatively large cohort of adults with amblyopia, allowed us, for the first time, to assess the link between visual function recovery and reduction in suppression. Surprisingly, no significant correlation was found between decreased suppression and improved visual function. This finding challenges the prevailing view and suggests that while dichoptic training improves visual acuity and stereopsis in adult amblyopia, reduced suppression is unlikely to be at the root of visual recovery. These results are discussed in the context of their implication on recovery of amblyopia in adults. PMID:25719537

  5. SAVS: A Space Analysis and Visualization System

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, Edward P.; Mankofsky, Alan; Goodrich, Charles C.

    1993-01-01

    We propose to develop, test, demonstrate, and deliver to NASA a powerful and versatile data acquisition, manipulation, analysis and visualization system which will enhance scientific capabilities in the display and interpretation of diverse and distributed data within an integrated user-friendly environment. Our approach exploits existing technologies and combines three major elements into an easy-to-use interactive package: (1) innovative visualization software; (2) advanced database techniques; and (3) a rich set of mathematical and image processing tools. Visualization capabilities will include one-, two-, and three-dimensinal displays, along with animation, compression, warping and slicing functions. Analysis tools will include generic mathematical and statistical techniques along with the ability to use large scale models for interactive interpretation of large volume data sets. Our system will be implemented on Sun and EC UNIX workstations and on the Stardent Graphics Supercomputer. Our final deliverable will include complete documentation and a NASA/NSF-CDAW/SUNDIAL campaign demonstration.

  6. SAVS: A Space Analysis and Visualization System

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, Edward P.; Mankofsky, Alan; Goodrich, Charles C.

    1992-01-01

    We propose to develop, test, demonstrate, and deliver to NASA a powerful and versatile data acquisition, manipulation, analysis and visualization system which will enhance scientific capabilities in the display and interpretation of diverse and distributed data within an integrated user-friendly environment. Our approach exploits existing technologies and combines three major elements into an easy-to-use interactive package: (1) innovative visualization software; (2) advanced database techniques; and (3) a rich set of mathematical and image processing tools. Visualization capabilities will include one-, two-, and three-dimensional displays, along with animation, compression, warping and slicing functions. Analysis tools will include generic mathematical and statistical techniques along with the ability to use large scale models for interactive interpretation of large volume data sets. Our system will be implemented on Sun and DEC UNIX workstations and on the Stardent Graphics Super computer. Our final deliverable will include complete documentation and a NASA/NSF-CDAW/SUNDIAL campaign demonstration.

  7. A new approach to visual system testing

    NASA Astrophysics Data System (ADS)

    Drozd, Maciej; Nowakowski, Antoni

    2005-09-01

    The experimental system was constructed for development and evaluation of visual brain potentials detection algorithm. Our experimental system consists of the developed, spherical, LED based perimeter head, a portable EEG recorder and a PC as a multitask unit. The computer enables full control of perimeter stimulation as well as acquisition and analysis of recorded EEG signals, using for visual response detection the newly developed VEPDA algorithm. Application of the VEPDA algorithm, based on Independent Component Analysis, allows much faster detection of visual evoked potentials comparing to traditional trial averaging routines. Main outcomes of this new approach are high reliability, considerable shortening of the examination time as well as possibility of objective examination - even patients not able to respond consciously, as very young children or elderly and intellectually handicapped patients.

  8. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible…

  9. Through Their Eyes: Are Characters with Visual Impairment Portrayed Realistically in Young Adult Literature?

    ERIC Educational Resources Information Center

    Carroll, Pamela S.; Rosenblum, L. Penny

    2000-01-01

    Defines a range of visual impairments that affect some adolescents. Examines the currently available young adult literature with characters who have vision disabilities. Provides a list of questions and criteria for evaluating and selecting young adult books that feature such characters, and includes a 13-item annotated bibliography of such books.…

  10. Integrated voice and visual systems research topics

    NASA Technical Reports Server (NTRS)

    Williams, Douglas H.; Simpson, Carol A.

    1986-01-01

    A series of studies was performed to investigate factors of helicopter speech and visual system design and measure the effects of these factors on human performance, both for pilots and non-pilots. The findings and conclusions of these studies were applied by the U.S. Army to the design of the Army's next generation threat warning system for helicopters and to the linguistic functional requirements for a joint Army/NASA flightworthy, experimental speech generation and recognition system.

  11. An atmospheric visual analysis and exploration system.

    PubMed

    Song, Yuyan; Ye, Jing; Svakhine, Nikolai; Lasher-Trapp, Sonia; Baldwin, Mike; Ebert, David S

    2006-01-01

    Meteorological research involves the analysis of multi-field, multi-scale, and multi-source data sets. In order to better understand these data sets, models and measurements at different resolutions must be analyzed. Unfortunately, traditional atmospheric visualization systems only provide tools to view a limited number of variables and small segments of the data. These tools are often restricted to two-dimensional contour or vector plots or three-dimensional isosurfaces. The meteorologist must mentally synthesize the data from multiple plots to glean the information needed to produce a coherent picture of the weather phenomenon of interest. In order to provide better tools to meteorologists and reduce system limitations, we have designed an integrated atmospheric visual analysis and exploration system for interactive analysis of weather data sets. Our system allows for the integrated visualization of 1D, 2D, and 3D atmospheric data sets in common meteorological grid structures and utilizes a variety of rendering techniques. These tools provide meteorologists with new abilities to analyze their data and answer questions on regions of interest, ranging from physics-based atmospheric rendering to illustrative rendering containing particles and glyphs. In this paper, we will discuss the use and performance of our visual analysis for two important meteorological applications. The first application is warm rain formation in small cumulus clouds. Here, our three-dimensional, interactive visualization of modeled drop trajectories within spatially correlated fields from a cloud simulation has provided researchers with new insight. Our second application is improving and validating severe storm models, specifically the Weather Research and Forecasting (WRF) model. This is done through correlative visualization of WRF model and experimental Doppler storm data.

  12. Pyridostigmine protects the soman challenged visual system

    SciTech Connect

    Kirby, A.W.; Townsend, A.T.; Evans, G.; Clarke, T.; Pope, C.

    1993-05-13

    The studies described here were designed to evaluate the protective action of pyridostigmine (pyrido) on visual processing following a soman challenge to fully anesthetized adult cats. The visual evoked response (VER) was used as our response measure, and all drugs were given i.v. Following soman, VERs in the adult cat show a preferential loss in low spatial frequency information which is dose dependent, and can be reversed with atropine. In our preparation, a single dose of 4 ug/kg soman given i.v. results in about 80% inhibition of blood cholinesterase (ChE) and 80-90% reduction in the VER. There is no spontaneous recovery of either parameter over the next 24 hours. Pretreatment with pyrido greatly alters the effect of 4 ug/kg soman. Enough pyrido to inhibit 60% blood ChE caused no change in the VER. After soman, ChE activity recovered to about 60% (40% inhibition) within several hours. Over the same period of time, VER reduction recovered to about 30% inhibition rather than 80% without pyrido.

  13. Selecting The ' Best ' Visual System: A Guide For Managers

    NASA Astrophysics Data System (ADS)

    Clapp, R. E.

    1985-05-01

    Choice of the "best" visual system for a given set of simulation training tasks is considered by many as a black magic process. Considerable confusion, misunderstanding and misapplication of visual requirements exists within the simulation community. Several elementary mistakes are frequently made, so that the simulation visual system is unsatisfactory for the simulation user. This paper presents management methodology for selection of the optimum visual system for a given set of simulation training tasks. Discussion of several current "pitfalls" in visual system use is given to increase confidence in choice methodology. Comparison tables are developed for current state-of-the-art visual systems to provide understanding of visual systems strengths and weaknesses.

  14. Visualizing Terrestrial and Aquatic Systems in 3D

    EPA Science Inventory

    The need for better visualization tools for environmental science is well documented, and the Visualization for Terrestrial and Aquatic Systems project (VISTAS) aims to both help scientists produce effective environmental science visualizations and to determine which visualizatio...

  15. Automated Visual Control System For Gob Feeders

    NASA Astrophysics Data System (ADS)

    Molesworth, Hugh; Vann, Tony

    1983-08-01

    The usable throughput and hence profitability of an automated glass bottle production line depends, amongst other factors, on the weight of glass in each bottle. Present techniques often rely on manual weighing of bottles on a sample basis with manual control of the feeder which forms the gobs from which the bottles are produced. Currently available automated weighing systems provide improved control although the weight measurement is still done only on a sample basis. All such weight measurement systems produce an undesirable delay before the bottle is safely available for weighing. This paper describes an automated visual gob weight control system which overcomes both of the above major limitations of existing control systems. The weight of every gob is calculated by visual scanning in free fall before the bottle is formed, allowing a fast and accurate closed-loop control system to be implemented.

  16. Visual and Auditory Morphological Priming in Adults with Developmental Dyslexia

    ERIC Educational Resources Information Center

    Raveh, Michal; Schiff, Rachel

    2008-01-01

    The quality of implicit morphological knowledge in adult Hebrew readers with developmental dyslexia was investigated. The priming paradigm was used to examine whether these adults extract and represent morphemic units similarly to normal readers during online word recognition. The group with dyslexia as a whole did not exhibit priming with visual…

  17. Age-related sensitive periods influence visual language discrimination in adults

    PubMed Central

    Weikum, Whitney M.; Vouloumanos, Athena; Navarra, Jordi; Soto-Faraco, Salvador; Sebastián-Gallés, Núria; Werker, Janet F.

    2013-01-01

    Adults as well as infants have the capacity to discriminate languages based on visual speech alone. Here, we investigated whether adults' ability to discriminate languages based on visual speech cues is influenced by the age of language acquisition. Adult participants who had all learned English (as a first or second language) but did not speak French were shown faces of bilingual (French/English) speakers silently reciting sentences in either language. Using only visual speech information, adults who had learned English from birth or as a second language before the age of 6 could discriminate between French and English significantly better than chance. However, adults who had learned English as a second language after age 6 failed to discriminate these two languages, suggesting that early childhood exposure is crucial for using relevant visual speech information to separate languages visually. These findings raise the possibility that lowered sensitivity to non-native visual speech cues may contribute to the difficulties encountered when learning a new language in adulthood. PMID:24312020

  18. Age-related sensitive periods influence visual language discrimination in adults.

    PubMed

    Weikum, Whitney M; Vouloumanos, Athena; Navarra, Jordi; Soto-Faraco, Salvador; Sebastián-Gallés, Núria; Werker, Janet F

    2013-01-01

    Adults as well as infants have the capacity to discriminate languages based on visual speech alone. Here, we investigated whether adults' ability to discriminate languages based on visual speech cues is influenced by the age of language acquisition. Adult participants who had all learned English (as a first or second language) but did not speak French were shown faces of bilingual (French/English) speakers silently reciting sentences in either language. Using only visual speech information, adults who had learned English from birth or as a second language before the age of 6 could discriminate between French and English significantly better than chance. However, adults who had learned English as a second language after age 6 failed to discriminate these two languages, suggesting that early childhood exposure is crucial for using relevant visual speech information to separate languages visually. These findings raise the possibility that lowered sensitivity to non-native visual speech cues may contribute to the difficulties encountered when learning a new language in adulthood.

  19. Visually Guided Navigation: Head-Mounted Eye-Tracking of Natural Locomotion in Children and Adults

    PubMed Central

    Franchak, John M.; Adolph, Karen E.

    2010-01-01

    The current study showed that visual fixation of obstacles is not required for rapid and adaptive navigation of obstacles. Children and adults wore a wireless, head-mounted eye-tracker during a visual search task in a room cluttered with obstacles. They spontaneously walked, jumped, and ran through the room, stepping up, down, and over obstacles. Both children and adults navigated adaptively without fixating obstacles, however, adults fixated less often than children. We discuss several possibilities for why obstacle navigation may shift from foveal to peripheral control over development. PMID:20932993

  20. A Behavioral Treatment for Traumatic Brain Injury-associated Visual Dysfunction Based on Adult Cortical Plasticity

    DTIC Science & Technology

    2011-10-01

    in amblyopic adults (Polat, 2008, Polat, Ma‐ Naim , Belkin & Sagi, 2004). We were  the first to show plasticity in adults with a visual deficit that...visual functions. Vision Res,   13    Polat, U., Ma‐ Naim , T., Belkin, M., & Sagi, D. (2004). Improving vision in adult amblyopia by  perceptual learning

  1. Visually guided navigation: head-mounted eye-tracking of natural locomotion in children and adults.

    PubMed

    Franchak, John M; Adolph, Karen E

    2010-12-01

    The current study showed that visual fixation of obstacles is not required for rapid and adaptive navigation of obstacles. Children and adults wore a wireless, head-mounted eye-tracker during a visual search task in a room cluttered with obstacles. They spontaneously walked, jumped, and ran through the room, stepping up, down, and over obstacles. Both children and adults navigated adaptively without fixating obstacles, however, adults fixated less often than children. We discuss several possibilities for why obstacle navigation may shift from foveal to peripheral control over development.

  2. Teaching Visually Impaired Adults with a Neuromuscular Disorder.

    ERIC Educational Resources Information Center

    Williams, Susan

    1983-01-01

    The effects of four neuromuscular disorders (stroke, Parkinson's disease, Huntington's disease, and Lou Gehrig's disease) on concommitant visual impairments are considered. Rehabilitation approaches and equipment that help clients cope with the condition are described. (CL)

  3. Visualization of complex hydrocarbon reaction systems

    SciTech Connect

    Shinn, J.H.

    1996-10-01

    Many hydrocarbon reactions of interest involve either poorly characterized reactants and products and/or large numbers of simultaneous reactions. An important step in understanding the behavior of such systems is to develop quantitative pictures of the feeds and products and the transformations which connect them. The processes for constructing these reaction visualizations is illustrated by examining the construction of a molecular model for coal liquefaction and subsequent conversion to distillate products, and the construction of a video simulation of catalytic petroleum naphtha reforming. New techniques which are permitting advances in these visualizations are discussed.

  4. Visualization of complex hydrocarbon reaction systems

    SciTech Connect

    Shinn, J.H.

    1996-12-31

    Many hydrocarbon reactions of interest involve either poorly characterized reactants and products and/or large numbers of simultaneous reactions. An important step in understanding the behavior of such systems is to develop quantitative pictures of the feeds and products and the transformations which connect them. The processes for constructing these reaction visualizations is illustrated by examining the construction of a molecular model for coal liquefaction and subsequent conversion to distillate products, and the construction of a video simulation of catalytic petroleum naphtha reforming. New technique which are permitting advances in these visualizations are discussed.

  5. Weakened Immune System and Adult Vaccination

    MedlinePlus

    ... for Healthcare Professionals Weakened Immune System and Adult Vaccination Recommend on Facebook Tweet Share Compartir Vaccines are ... up to age 26 years Learn about adult vaccination and other health conditions Asplenia Diabetes Type 1 ...

  6. Audiovisual Integration Delayed by Stimulus Onset Asynchrony Between Auditory and Visual Stimuli in Older Adults.

    PubMed

    Ren, Yanna; Yang, Weiping; Nakahashi, Kohei; Takahashi, Satoshi; Wu, Jinglong

    2017-02-01

    Although neuronal studies have shown that audiovisual integration is regulated by temporal factors, there is still little knowledge about the impact of temporal factors on audiovisual integration in older adults. To clarify how stimulus onset asynchrony (SOA) between auditory and visual stimuli modulates age-related audiovisual integration, 20 younger adults (21-24 years) and 20 older adults (61-80 years) were instructed to perform an auditory or visual stimuli discrimination experiment. The results showed that in younger adults, audiovisual integration was altered from an enhancement (AV, A ± 50 V) to a depression (A ± 150 V). In older adults, the alterative pattern was similar to that for younger adults with the expansion of SOA; however, older adults showed significantly delayed onset for the time-window-of-integration and peak latency in all conditions, which further demonstrated that audiovisual integration was delayed more severely with the expansion of SOA, especially in the peak latency for V-preceded-A conditions in older adults. Our study suggested that audiovisual facilitative integration occurs only within a certain SOA range (e.g., -50 to 50 ms) in both younger and older adults. Moreover, our results confirm that the response for older adults was slowed and provided empirical evidence that integration ability is much more sensitive to the temporal alignment of audiovisual stimuli in older adults.

  7. Visual navigation system for autonomous indoor blimps

    NASA Astrophysics Data System (ADS)

    Campos, Mario F.; de Souza Coelho, Lucio

    1999-07-01

    Autonomous dirigibles - aerial robots that are a blimp controlled by computer based on information gathered by sensors - are a new and promising research field in Robotics, offering several original work opportunities. One of them is the study of visual navigation of UAVs. In the work described in this paper, a Computer Vision and Control system was developed to perform automatically very simple navigation task for a small indoor blimp. The vision system is able to track artificial visual beacons - objects with known geometrical properties - and from them a geometrical methodology can extract information about orientation of the blimp. The tracking of natural landmarks is also a possibility for the vision technique developed. The control system uses that data to keep the dirigible on a programmed orientation. Experimental results showing the correct and efficient functioning of the system are shown and have your implications and future possibilities discussed.

  8. Visual function and color vision in adults with Attention-Deficit/Hyperactivity Disorder

    PubMed Central

    Kim, Soyeon; Chen, Samantha; Tannock, Rosemary

    2013-01-01

    Purpose Color vision and self-reported visual function in everyday life in young adults with Attention-Deficit/Hyperactivity Disorder (ADHD) were investigated. Method Participants were 30 young adults with ADHD and 30 controls matched for age and gender. They were tested individually and completed the Visual Activities Questionnaire (VAQ), Farnsworth-Munsell 100 Hue Test (FMT) and A Quick Test of Cognitive Speed (AQT). Results The ADHD group reported significantly more problems in 4 of 8 areas on the VAQ: depth perception, peripheral vision, visual search and visual processing speed. Further analyses of VAQ items revealed that the ADHD group endorsed more visual problems associated with driving than controls. Color perception difficulties on the FMT were restricted to the blue spectrum in the ADHD group. FMT and AQT results revealed slower processing of visual stimuli in the ADHD group. Conclusion A comprehensive investigation of mechanisms underlying visual function and color vision in adults with ADHD is warranted, along with the potential impact of these visual problems on driving performance. PMID:24646898

  9. The Auditory-Visual Speech Benefit on Working Memory in Older Adults with Hearing Impairment

    PubMed Central

    Frtusova, Jana B.; Phillips, Natalie A.

    2016-01-01

    This study examined the effect of auditory-visual (AV) speech stimuli on working memory in older adults with poorer-hearing (PH) in comparison to age- and education-matched older adults with better hearing (BH). Participants completed a working memory n-back task (0- to 2-back) in which sequences of digits were presented in visual-only (i.e., speech-reading), auditory-only (A-only), and AV conditions. Auditory event-related potentials (ERP) were collected to assess the relationship between perceptual and working memory processing. The behavioral results showed that both groups were faster in the AV condition in comparison to the unisensory conditions. The ERP data showed perceptual facilitation in the AV condition, in the form of reduced amplitudes and latencies of the auditory N1 and/or P1 components, in the PH group. Furthermore, a working memory ERP component, the P3, peaked earlier for both groups in the AV condition compared to the A-only condition. In general, the PH group showed a more robust AV benefit; however, the BH group showed a dose-response relationship between perceptual facilitation and working memory improvement, especially for facilitation of processing speed. Two measures, reaction time and P3 amplitude, suggested that the presence of visual speech cues may have helped the PH group to counteract the demanding auditory processing, to the level that no group differences were evident during the AV modality despite lower performance during the A-only condition. Overall, this study provides support for the theory of an integrated perceptual-cognitive system. The practical significance of these findings is also discussed. PMID:27148106

  10. Dependency visualization for complex system understanding

    SciTech Connect

    Smart, J. Allison Cory

    1994-09-01

    With the volume of software in production use dramatically increasing, the importance of software maintenance has become strikingly apparent. Techniques now sought and developed for reverse engineering and design extraction and recovery. At present, numerous commercial products and research tools exist which are capable of visualizing a variety of programming languages and software constructs. The list of new tools and services continues to grow rapidly. Although the scope of the existing commercial and academic product set is quite broad, these tools still share a common underlying problem. The ability of each tool to visually organize object representations is increasingly impaired as the number of components and component dependencies within systems increases. Regardless of how objects are defined, complex ``spaghetti`` networks result in nearly all large system cases. While this problem is immediately apparent in modem systems analysis involving large software implementations, it is not new. As will be discussed in Chapter 2, related problems involving the theory of graphs were identified long ago. This important theoretical foundation provides a useful vehicle for representing and analyzing complex system structures. While the utility of directed graph based concepts in software tool design has been demonstrated in literature, these tools still lack the capabilities necessary for large system comprehension. This foundation must therefore be expanded with new organizational and visualization constructs necessary to meet this challenge. This dissertation addresses this need by constructing a conceptual model and a set of methods for interactively exploring, organizing, and understanding the structure of complex software systems.

  11. Mobile visual examination and repackaging (MOVER) system

    SciTech Connect

    Los Alamos National Laboratory

    2001-01-01

    Process engineering and waste technology teams at LOS Alamos National Laboratory delivered a prototype Mobile Visual Examination and Repackaging (MOVER) system to the Waste Isolation Pilot Plant (WIPP) outside of Carlsbad, NM in October, 2000. This system was developed in response to compliance issues with legacy waste that was packaged in 55 gallons drums prior to release of WIPP's waste acceptance criteria (WAC). A statistical percentage of these 55 gallon drums will be opened and visually examined (VE) as part of re-characterization using Non-destructive examination (NDE) procedures. VE is an intrusive technique since the drum is opened, and as a result, there are more risks in spreading contamination. Hence, VE is performed in a glovebox to protect the workers and the environment. During VE, waste is pulled out of one drum, visually examined, the amount of plutonium measured if necessary, and the waste repackaged into one or more drums. MOVER can perform all these operations, along with having the capability to house the glovebox operations and all support equipment in a 40-foot-long container that can be transported to a site on a semi-trailer. This container is divided into three rooms, providing the level of safety and containment of a fixed facility. A key asset of mobile systems is the inherent need for modular design that reduces infrastructure costs and overhead. A mobile system like MOVER represents a technology base aimed at meeting DOE schedules to accelerate decommissioning of many sites.

  12. Resilience in Parents of Young Adults with Visual Impairments

    ERIC Educational Resources Information Center

    de Klerk, Heidi; Greeff, Abraham P.

    2011-01-01

    This article reports on a study of the adaptation of parents with children with visual impairment in South Africa. The results showed that familial values (such as attitude toward the disability, religious faith, and familial closeness) permit a process of inclusion (through the use of resources and acceptance of help) and the development of a…

  13. Effects of Distraction on Visual Enumeration in Children and Adults

    ERIC Educational Resources Information Center

    Maylor, Elizabeth A.; Watson, Derrick G.; Hartley, Emma L.

    2011-01-01

    Speeded enumeration of visual stimuli typically produces a bilinear function, with a shallow subitizing rate (less than 100 ms/item) up to 3-4 items (subitizing span) and a steeper counting rate ([image omitted]300 ms/item) thereafter. FINST theory (L. M. Trick & Z. W. Pylyshyn, 1993, 1994) suggests that subitizing of targets is possible in…

  14. Centre Computer Base for Visually Handicapped Children, Students and Adults.

    ERIC Educational Resources Information Center

    Spencer, S.; And Others

    1987-01-01

    The Centre Computer Base is a list of hardware which can effectively operate the software of the Research Centre for the Education of the Visually Handicapped. Essential hardware contained on the list is described, along with a variety of "add-on" devices such as joysticks, touch-screens, speech synthesizers, braille embossers, etc.…

  15. Infant's visual preferences for facial traits associated with adult attractiveness judgements: data from eye-tracking.

    PubMed

    Griffey, Jack A F; Little, Anthony C

    2014-08-01

    Human preferences for facial attractiveness appear to emerge at an early stage during infant development. A number of studies have demonstrated that infants display a robust preference for facial attractiveness, preferring to look at physically attractive faces versus less attractive faces as judged by adults. However, to-date, relatively little is known about which traits of the face infants use to base these preferences upon. In contrast, a large number of studies conducted with human adults have identified that preference for attractive faces can be attributed to a number of specific facial traits. The purpose of the experiments here was to measure and assess infant's visual preference via eye-tracker technology for faces manipulated for one of three traits known to effect attractiveness judgments in adult preference tests: symmetry, averageness, and sexually dimorphic traits. Sixty-four infants (28 female and 36 male) aged between 12 and 24 months old each completed a visual paired comparison (VPC) task for one of the three facial dimensions investigated. Data indicated that infants displayed a significant visual preference for facial symmetry analogous to those preferences displayed by adults. Infants also displayed a significant visual preference for feminine versions of faces, in line with some studies of adult preferences. Visual preferences for facial non-averageness, or distinctiveness were also seen, a pattern opposite to that seen in adults. These findings demonstrate that infant's appreciation for facial attractiveness in adult images between the ages of 12 and 24 months of age is based on some, but not all, traits that adults find attractive.

  16. Sensory experience during locomotion promotes recovery of function in adult visual cortex.

    PubMed

    Kaneko, Megumi; Stryker, Michael P

    2014-06-26

    Recovery from sensory deprivation is slow and incomplete in adult visual cortex. In this study, we show that visual stimulation during locomotion, which increases the gain of visual responses in primary visual cortex, dramatically enhances recovery in the mouse. Excitatory neurons regained normal levels of response, while narrow-spiking (inhibitory) neurons remained less active. Visual stimulation or locomotion alone did not enhance recovery. Responses to the particular visual stimuli viewed by the animal during locomotion recovered, while those to another normally effective stimulus did not, suggesting that locomotion promotes the recovery only of the neural circuits that are activated concurrent with the locomotion. These findings may provide an avenue for improving recovery from amblyopia in humans.DOI: http://dx.doi.org/10.7554/eLife.02798.001.

  17. Visually Exploring Worldwide Incidents Tracking System Data

    SciTech Connect

    Chhatwal, Shree D.; Rose, Stuart J.

    2008-01-27

    This paper presents refinements of an existing analytic tool, Juxter, which was developed for the visualization of multi-dimensional categorical data, and explores its application to support exploration and interaction with open source Worldwide Incidents Tracking System (WITS) data. The volume and complexity of data available on terrorism makes it hard to analyze. Information systems that can efficiently and effectively collect, access, analyze, and report terrorist incidents can help in further studies focused on preventing, detecting, and responding to terrorist attacks. Existing interfaces to the WITS data support advanced search capabilities, and geolocation but lack functionality for identifying patterns and trends. To better support efficient browsing we have refined Juxter’s existing capabilities for filtering, selecting, and sorting elements and categories within the visualization.

  18. A Space and Atmospheric Visualization Science System

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, E. P.; Blanchard, P.; Mankofsky, A.; Goodrich, C.; Kamins, D.; Kulkarni, R.; Mcnabb, D.; Moroh, M.

    1994-01-01

    SAVS (a Space and Atmospheric Visualization Science system) is an integrated system with user-friendly functionality that employs a 'push-button' software environment that mimics the logical scientific processes in data acquisition, reduction, analysis, and visualization. All of this is accomplished without requiring a detailed understanding of the methods, networks, and modules that link the tools and effectively execute the functions. This report describes SAVS and its components, followed by several applications based on generic research interests in interplanetary and magnetospheric physics (IMP/ISTP), active experiments in space (CRRES), and mission planning focused on the earth's thermospheric, ionospheric, and mesospheric domains (TIMED). The final chapters provide a user-oriented description of interface functionalities, hands-on operations, and customized modules, with details of the primary modules presented in the appendices. The overall intent of the report is to reflect the accomplishments of the three-year development effort and to introduce potential users to the power and utility of the integrated data acquisition, analysis, and visualization system.

  19. Visual Awareness Is Limited by the Representational Architecture of the Visual System.

    PubMed

    Cohen, Michael A; Nakayama, Ken; Konkle, Talia; Stantić, Mirta; Alvarez, George A

    2015-11-01

    Visual perception and awareness have strict limitations. We suggest that one source of these limitations is the representational architecture of the visual system. Under this view, the extent to which items activate the same neural channels constrains the amount of information that can be processed by the visual system and ultimately reach awareness. Here, we measured how well stimuli from different categories (e.g., faces and cars) blocked one another from reaching awareness using two distinct paradigms that render stimuli invisible: visual masking and continuous flash suppression. Next, we used fMRI to measure the similarity of the neural responses elicited by these categories across the entire visual hierarchy. Overall, we found strong brain-behavior correlations within the ventral pathway, weaker correlations in the dorsal pathway, and no correlations in early visual cortex (V1-V3). These results suggest that the organization of higher level visual cortex constrains visual awareness and the overall processing capacity of visual cognition.

  20. Project DyAdd: visual attention in adult dyslexia and ADHD.

    PubMed

    Laasonen, Marja; Salomaa, Jonna; Cousineau, Denis; Leppämäki, Sami; Tani, Pekka; Hokkanen, Laura; Dye, Matthew

    2012-12-01

    In this study of the project DyAdd, three aspects of visual attention were investigated in adults (18-55years) with dyslexia (n=35) or attention deficit/hyperactivity disorder (ADHD, n=22), and in healthy controls (n=35). Temporal characteristics of visual attention were assessed with Attentional Blink (AB), capacity of visual attention with Multiple Object Tracking (MOT), and spatial aspects of visual attention with Useful Field of View (UFOV) task. Results showed that adults with dyslexia had difficulties performing the AB and UFOV tasks, which were explained by an impaired ability to process dual targets, longer AB recovery time, and deficits in processing rapidly changing visual displays. The ADHD group did not have difficulties in any of the tasks. Further, performance in the visual attention tasks predicted variation in measures of phonological processing and reading when all of the participants were considered together. Thus, difficulties in tasks of visual attention were related to dyslexia and variation of visual attention had a role in the reading ability of the general population.

  1. Reading speed in the peripheral visual field of older adults: Does it benefit from perceptual learning?

    PubMed

    Yu, Deyue; Cheung, Sing-Hang; Legge, Gordon E; Chung, Susana T L

    2010-04-21

    Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults (Chung, Legge, & Cheung, 2004). Here we ask whether the same happens in older adults in an age range more typical of the onset of AMD. Eighteen normally-sighted subjects, aged 55-76years, were randomly assigned to training or control groups. Visual-span profiles (plots of letter-recognition accuracy as a function of horizontal letter position) and RSVP reading speeds were measured at 10 degrees above and below fixation during pre- and post-tests for all subjects. Training consisted of repeated measurements of visual-span profiles at 10 degrees below fixation, in four daily sessions. The control subjects did not receive any training. Perceptual learning enlarged the visual spans in both trained (lower) and untrained (upper) visual fields. Reading speed improved in the trained field by 60% when the trained print size was used. The training benefits for these older subjects were weaker than the training benefits for young adults found by Chung et al. Despite the weaker training benefits, perceptual learning remains a potential option for low-vision reading rehabilitation among older adults.

  2. Visual attention in adults with developmental dyslexia: evidence from manual reaction time and saccade latency.

    PubMed

    Judge, Jeannie; Caravolas, Markéta; Knox, Paul C

    2007-05-01

    Two studies were conducted to investigate visual attention deficits in dyslexia. In Experiment 1, adults with dyslexia and age- and IQ-matched controls completed a simple cueing task; participants responded to briefly presented (20 ms) eccentric targets (3 degrees , 6 degrees , or 9 degrees ) with a key press. In Experiment 2, the same participants completed a saccade version of the task, and saccade amplitude, accuracy, and latency were measured. The results revealed comparable performance between the groups on the manual reaction time task. The groups also performed similarly in saccade accuracy and latency. Moreover, neither group showed a visual field asymmetry in their performance, with the exception that adults with dyslexia showed longer saccade latency for 9 degrees targets presented to their left visual field than did controls. However, on the latter measure, the majority (78%) of those with dyslexia performed within the range of the control group. Correlational analyses revealed associations between reading and phoneme awareness in both groups, but phoneme awareness was not associated with visual attention in adult dyslexics. Together, the results are not compatible with a visual attention deficit in adult dyslexia, while they provide support for the phonological deficit hypothesis.

  3. Reading Speed in the peripheral visual field of older adults: Does it benefit from perceptual learning?

    PubMed Central

    Yu, Deyue; Cheung, Sing-Hang; Legge, Gordon E.; Chung, Susana T. L.

    2010-01-01

    Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults (Chung, Legge & Cheung, 2004). Here we ask whether the same happens in older adults in an age range more typical of the onset of AMD. Eighteen normally-sighted subjects, aged 55 to 76 years, were randomly assigned to training or control groups. Visual-span profiles (plots of letter-recognition accuracy as a function of horizontal letter position) and RSVP reading speeds were measured at 10° above and below fixation during pre- and post-tests for all subjects. Training consisted of repeated measurements of visual-span profiles at 10° below fixation, in 4 daily sessions. The control subjects did not receive any training. Perceptual learning enlarged the visual spans in both trained (lower) and untrained (upper) visual fields. Reading speed improved in the trained field by 60% when the trained print size was used. The training benefits for these older subjects were weaker than the training benefits for young adults found by Chung et al. Despite the weaker training benefits, perceptual learning remains a potential option for low-vision reading rehabilitation among older adults. PMID:20156473

  4. Evaluation of vestibular and dynamic visual acuity in adults with congenital deafness.

    PubMed

    Nakajima, Yukinori; Kaga, Kimitaka; Takekoshi, Hideki; Sakuraba, Keisyoku

    2012-10-01

    This study compared vestibular and dynamic visual acuity in 19 adult athletes with deafness participating in Deaflympics to those of 25 young adults with normal hearing. Balance capability was evaluated using a one-leg standing test with eyes open and stabilometry. Caloric tests and vestibular evoked myogenic potential tests were conducted to test vestibular function. Visual function was evaluated using a dynamic visual acuity test. No significant difference was found between results of the one-leg standing test with eyes open and stabilometry with eyes open. Athletes with deafness performed better than normal hearing young adults with eyes closed. The caloric test indicated hypofunction of the lateral semicircular canal function in 5 of the 19 athletes with deafness. Balance-function tests showed normal results for both groups. The results for athletes with deafness on visual acuity were better than those of controls. Young Deaflympics athletes with deafness can adjust their balance function as well as or better than normal hearing young adults using dynamic visual acuity.

  5. Investigating visual-tactile interactions over time and space in adults with autism.

    PubMed

    Poole, Daniel; Gowen, Emma; Warren, Paul A; Poliakoff, Ellen

    2015-10-01

    It has been suggested that the sensory symptoms which affect many people with autism spectrum conditions (ASC) may be related to alterations in multisensory processing. Typically, the likelihood of interactions between the senses increases when information is temporally and spatially coincident. We explored visual-tactile interactions in adults with ASC for the first time in two experiments using low-level stimuli. Both participants with ASC and matched neurotypical controls only produced crossmodal interactions to near simultaneous stimuli, suggesting that temporal modulation is unaffected in the adult population. We also provide preliminary evidence that visual-tactile interactions may occur over greater spatial distances in participants with ASC, which merits further exploration.

  6. Diabetes reduces the cognitive function with the decrease of the visual perception and visual motor integration in male older adults.

    PubMed

    Yun, Hyo-Soon; Kim, Eunhwi; Suh, Soon-Rim; Kim, Mi-Han; Kim, Hong

    2013-01-01

    This study investigated the influence of diabetes on cognitive decline between the diabetes and non- diabetes patients and identified the associations between diabetes and cognitive function, visual perception (VP), and visual motor integration (VMI). Sixty elderly men (67.10± 1.65 yr) with and without diabetes (n= 30 in each group) who were surveyed by interview and questionnaire in South Korea were enrolled in this study. The score of Mini-Mental State Examination of Korean version (MMSE-KC), Motor-free Visual Perception Test-Vertical Format (MVPT-V), and Visual-Motor Integration 3rd Revision (VMI-3R) were assessed in all of the participants to evaluate cognitive function, VP, and VMI in each. The score of MMSE-KC in the diabetic group was significantly lower than that of the non-diabetes group (P< 0.01). Participants in the diabetes group also had lower MVPT-V and VMI-3R scores than those in the non-diabetes group (P< 0.01, respectively). Especially, the scores of figure-ground and visual memory among the subcategories of MVPT-V were significantly lower in the diabetes group than in the non-diabetes group (P< 0.01). These findings indicate that the decline in cognitive function in individuals with diabetes may be greater than that in non-diabetics. In addition, the cognitive decline in older adults with diabetes might be associated with the decrease of VP and VMI. In conclusion, we propose that VP and VMI will be helpful to monitor the change of cognitive function in older adults with diabetes as part of the routine management of diabetes-induced cognitive declines.

  7. Effects of visual fatigue caused by smartphones on balance function in healthy adults

    PubMed Central

    Park, Young-Hyun; An, Chang-Man; Moon, Sung-Jun

    2017-01-01

    [Purpose] The purpose of this study was to determine the effects of visual fatigue caused by smartphone use on balance function. [Subjects and Methods] The participants consisted of 22 healthy male and female adults. Their postural stability, limit of stability, and limit of stability running time were evaluated using a computerized posturography apparatus before and after inducing visual fatigue. Postural stability and the limit of stability were divided into static and dynamic conditions. [Results] There were significant differences between the dynamic postural stability, the static and dynamic limit of stability, and both the static and dynamic limit of stability running times after the induction of visual fatigue. [Conclusion] The results showed that visual fatigue caused by smartphone use has a negative effect on balance function. Therefore, reducing visual fatigue through proper rest is necessary. PMID:28265143

  8. Locomotion Induces Stimulus-Specific Response Enhancement in Adult Visual Cortex.

    PubMed

    Kaneko, Megumi; Fu, Yu; Stryker, Michael P

    2017-03-29

    The responses of neurons in the visual cortex (V1) of adult mammals have long been thought to be stable over long periods. Here, we investigated whether repeated exposure to specific stimuli would enhance V1 visual responses in mice using intrinsic signal imaging through the intact skull and two-photon imaging of calcium signals in single neurons. Mice ran on Styrofoam balls floating on air while viewing one of three different, high-contrast visual stimuli. V1 responses to the stimuli that were viewed by the animal were specifically enhanced, while responses to other stimuli were unaffected. Similar exposure in stationary mice or in mice in which NMDA receptors were partially blocked did not significantly enhance responses. These findings indicate that stimulus-specific plasticity in the adult visual cortex depends on concurrent locomotion, presumably as a result of the high-gain state of the visual cortex induced by locomotion.SIGNIFICANCE STATEMENT We report a rapid and persistent increase in visual cortical responses to visual stimuli presented during locomotion in intact mice. We first used a method that is completely noninvasive to image intrinsic signals through the intact skull. We then measured the same effects on single neurons using two-photon calcium imaging and found that the increase in response to a particular stimulus produced by locomotion depends on how well the neuron is initially driven by the stimulus. To our knowledge, this is the first time such enhancement has been described in single neurons or using noninvasive measurements.

  9. Holodeck: Telepresence Dome Visualization System Simulations

    NASA Technical Reports Server (NTRS)

    Hite, Nicolas

    2012-01-01

    This paper explores the simulation and consideration of different image-projection strategies for the Holodeck, a dome that will be used for highly immersive telepresence operations in future endeavors of the National Aeronautics and Space Administration (NASA). Its visualization system will include a full 360 degree projection onto the dome's interior walls in order to display video streams from both simulations and recorded video. Because humans innately trust their vision to precisely report their surroundings, the Holodeck's visualization system is crucial to its realism. This system will be rigged with an integrated hardware and software infrastructure-namely, a system of projectors that will relay with a Graphics Processing Unit (GPU) and computer to both project images onto the dome and correct warping in those projections in real-time. Using both Computer-Aided Design (CAD) and ray-tracing software, virtual models of various dome/projector geometries were created and simulated via tracking and analysis of virtual light sources, leading to the selection of two possible configurations for installation. Research into image warping and the generation of dome-ready video content was also conducted, including generation of fisheye images, distortion correction, and the generation of a reliable content-generation pipeline.

  10. Effects of Fluoxetine and Visual Experience on Glutamatergic and GABAergic Synaptic Proteins in Adult Rat Visual Cortex123

    PubMed Central

    Beshara, Simon; Beston, Brett R.; Pinto, Joshua G. A.

    2015-01-01

    Abstract Fluoxetine has emerged as a novel treatment for persistent amblyopia because in adult animals it reinstates critical period-like ocular dominance plasticity and promotes recovery of visual acuity. Translation of these results from animal models to the clinic, however, has been challenging because of the lack of understanding of how this selective serotonin reuptake inhibitor affects glutamatergic and GABAergic synaptic mechanisms that are essential for experience-dependent plasticity. An appealing hypothesis is that fluoxetine recreates a critical period (CP)-like state by shifting synaptic mechanisms to be more juvenile. To test this we studied the effect of fluoxetine treatment in adult rats, alone or in combination with visual deprivation [monocular deprivation (MD)], on a set of highly conserved presynaptic and postsynaptic proteins (synapsin, synaptophysin, VGLUT1, VGAT, PSD-95, gephyrin, GluN1, GluA2, GluN2B, GluN2A, GABAAα1, GABAAα3). We did not find evidence that fluoxetine shifted the protein amounts or balances to a CP-like state. Instead, it drove the balances in favor of the more mature subunits (GluN2A, GABAAα1). In addition, when fluoxetine was paired with MD it created a neuroprotective-like environment by normalizing the glutamatergic gain found in adult MDs. Together, our results suggest that fluoxetine treatment creates a novel synaptic environment dominated by GluN2A- and GABAAα1-dependent plasticity. PMID:26730408

  11. Effects of Fluoxetine and Visual Experience on Glutamatergic and GABAergic Synaptic Proteins in Adult Rat Visual Cortex.

    PubMed

    Beshara, Simon; Beston, Brett R; Pinto, Joshua G A; Murphy, Kathryn M

    2015-01-01

    Fluoxetine has emerged as a novel treatment for persistent amblyopia because in adult animals it reinstates critical period-like ocular dominance plasticity and promotes recovery of visual acuity. Translation of these results from animal models to the clinic, however, has been challenging because of the lack of understanding of how this selective serotonin reuptake inhibitor affects glutamatergic and GABAergic synaptic mechanisms that are essential for experience-dependent plasticity. An appealing hypothesis is that fluoxetine recreates a critical period (CP)-like state by shifting synaptic mechanisms to be more juvenile. To test this we studied the effect of fluoxetine treatment in adult rats, alone or in combination with visual deprivation [monocular deprivation (MD)], on a set of highly conserved presynaptic and postsynaptic proteins (synapsin, synaptophysin, VGLUT1, VGAT, PSD-95, gephyrin, GluN1, GluA2, GluN2B, GluN2A, GABAAα1, GABAAα3). We did not find evidence that fluoxetine shifted the protein amounts or balances to a CP-like state. Instead, it drove the balances in favor of the more mature subunits (GluN2A, GABAAα1). In addition, when fluoxetine was paired with MD it created a neuroprotective-like environment by normalizing the glutamatergic gain found in adult MDs. Together, our results suggest that fluoxetine treatment creates a novel synaptic environment dominated by GluN2A- and GABAAα1-dependent plasticity.

  12. A Behavioral Treatment for Traumatic Brain Injury-Associated Visual Dysfunction Based on Adult Cortical Plasticity

    DTIC Science & Technology

    2012-10-01

    amblyopic adults (Polat, 2008, Polat, Ma‐ Naim , Belkin & Sagi, 2004). We were  the first to show plasticity in adults with a visual deficit that was...Ma‐ Naim , T., Belkin, M., & Sagi, D. (2004). Improving vision in adult amblyopia by  perceptual learning. Proc Natl Acad Sci U S A, 101 (17), 6692

  13. Exploring Childhood Memories with Adult Survivors of Sexual Abuse: Concrete Reconstruction and Visualization Techniques.

    ERIC Educational Resources Information Center

    Roland, Catherine B.

    1993-01-01

    Describes two memory-enhancing techniques, visualization and concrete reconstruction, that have been successful in counseling adult survivors of sexual abuse. Includes suggested implementations, case examples, and implications for incorporating memory techniques into counseling process. Describes various risk factors involved in using these…

  14. Optimization of Visual Training for Full Recovery from Severe Amblyopia in Adults

    ERIC Educational Resources Information Center

    Eaton, Nicolette C.; Sheehan, Hanna Marie; Quinlan, Elizabeth M.

    2016-01-01

    The severe amblyopia induced by chronic monocular deprivation is highly resistant to reversal in adulthood. Here we use a rodent model to show that recovery from deprivation amblyopia can be achieved in adults by a two-step sequence, involving enhancement of synaptic plasticity in the visual cortex by dark exposure followed immediately by visual…

  15. The Relationship of Perceived Social Support with Well-Being in Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Guerette, Amy R.; Smedema, Susan Miller

    2011-01-01

    The relationship between perceived social support and multiple indicators of well-being in adults with visual impairments was investigated. The results included significant correlation of social support and depressive symptoms, satisfaction with life, as well as with physical, psychological, economic, family, and social well-being. Implications…

  16. Resting state neural networks for visual Chinese word processing in Chinese adults and children.

    PubMed

    Li, Ling; Liu, Jiangang; Chen, Feiyan; Feng, Lu; Li, Hong; Tian, Jie; Lee, Kang

    2013-07-01

    This study examined the resting state neural networks for visual Chinese word processing in Chinese children and adults. Both the functional connectivity (FC) and amplitude of low frequency fluctuation (ALFF) approaches were used to analyze the fMRI data collected when Chinese participants were not engaged in any specific explicit tasks. We correlated time series extracted from the visual word form area (VWFA) with those in other regions in the brain. We also performed ALFF analysis in the resting state FC networks. The FC results revealed that, regarding the functionally connected brain regions, there exist similar intrinsically organized resting state networks for visual Chinese word processing in adults and children, suggesting that such networks may already be functional after 3-4 years of informal exposure to reading plus 3-4 years formal schooling. The ALFF results revealed that children appear to recruit more neural resources than adults in generally reading-irrelevant brain regions. Differences between child and adult ALFF results suggest that children's intrinsic word processing network during the resting state, though similar in functional connectivity, is still undergoing development. Further exposure to visual words and experience with reading are needed for children to develop a mature intrinsic network for word processing. The developmental course of the intrinsically organized word processing network may parallel that of the explicit word processing network.

  17. Shaping with Visual Feedback and Token Reinforcement: Effects on Voice Volume Changes in Mentally Retarded Adults.

    ERIC Educational Resources Information Center

    Bieber, Carrie; Gurski, John C.

    In an attempt to confirm earlier results with a group of mentally retarded females, 12 mentally retarded institutionalized adults (8 male, 4 female) were trained to either reduce (Loud group) or increase (Soft group) their voice volumes with a combination of visual feedback and token reinforcement. The feedback unit provided a binary light on-off…

  18. The Shared Signal Hypothesis: Effects of Emotion-Gaze Congruency in Infant and Adult Visual Preferences

    ERIC Educational Resources Information Center

    Rigato, Silvia; Menon, Enrica; Farroni, Teresa; Johnson, Mark H.

    2013-01-01

    In this study, 4-month-old infants' and adults' spontaneous preferences for emotional and neutral displays with direct and averted gaze are investigated using visual preference paradigms. Specifically, by presenting two approach-oriented emotions (happiness and anger) and two avoidance-oriented emotions (fear and sadness), we asked whether the…

  19. Atypical Visual Orienting to Gaze- and Arrow-Cues in Adults with High Functioning Autism

    ERIC Educational Resources Information Center

    Vlamings, Petra H. J. M.; Stauder, Johannes E. A.; van Son, Ilona A. M.; Mottron, Laurent

    2005-01-01

    The present study investigates visual orienting to directional cues (arrow or eyes) in adults with high functioning autism (n = 19) and age matched controls (n = 19). A choice reaction time paradigm is used in which eye-or arrow direction correctly (congruent) or incorrectly (incongruent) cues target location. In typically developing participants,…

  20. Adults with Dyslexia Show Deficits on Spatial Frequency Doubling and Visual Attention Tasks

    ERIC Educational Resources Information Center

    Buchholz, Judy; McKone, Elinor

    2004-01-01

    We examine the visual processing of high-functioning adults with developmental dyslexia (mean Performance IQ=126.5) and current phonological problems. In comparison to an age- and IQ-matched control group, the group with dyslexia showed deficits in two tasks associated with magnocellular/dorsal pathway function. For the "frequency doubling"…

  1. Impaired Visual Expertise for Print in French Adults with Dyslexia as Shown by N170 Tuning

    ERIC Educational Resources Information Center

    Mahe, Gwendoline; Bonnefond, Anne; Gavens, Nathalie; Dufour, Andre; Doignon-Camus, Nadege

    2012-01-01

    Efficient reading relies on expertise in the visual word form area, with abnormalities in the functional specialization of this area observed in individuals with developmental dyslexia. We have investigated event related potentials in print tuning in adults with dyslexia, based on their N170 response at 135-255 ms. Control and dyslexic adults…

  2. Visual-Attentional Span and Lexical ­Decision in Skilled Adult Readers

    ERIC Educational Resources Information Center

    Holmes, Virginia M.; Dawson, Georgia

    2014-01-01

    The goal of the study was to examine the association between visual-attentional span and lexical decision in skilled adult readers. In the span tasks, an array of letters was presented briefly and recognition or production of a single cued letter (partial span) or production of all letters (whole span) was required. Independently of letter…

  3. Visual field bias in hearing and deaf adults during judgments of facial expression and identity

    PubMed Central

    Letourneau, Susan M.; Mitchell, Teresa V.

    2013-01-01

    The dominance of the right hemisphere during face perception is associated with more accurate judgments of faces presented in the left rather than the right visual field (RVF). Previous research suggests that the left visual field (LVF) bias typically observed during face perception tasks is reduced in deaf adults who use sign language, for whom facial expressions convey important linguistic information. The current study examined whether visual field biases were altered in deaf adults whenever they viewed expressive faces, or only when attention was explicitly directed to expression. Twelve hearing adults and 12 deaf signers were trained to recognize a set of novel faces posing various emotional expressions. They then judged the familiarity or emotion of faces presented in the left or RVF, or both visual fields simultaneously. The same familiar and unfamiliar faces posing neutral and happy expressions were presented in the two tasks. Both groups were most accurate when faces were presented in both visual fields. Across tasks, the hearing group demonstrated a bias toward the LVF. In contrast, the deaf group showed a bias toward the LVF during identity judgments that shifted marginally toward the RVF during emotion judgments. Two secondary conditions tested whether these effects generalized to angry faces and famous faces and similar effects were observed. These results suggest that attention to facial expression, not merely the presence of emotional expression, reduces a typical LVF bias for face processing in deaf signers. PMID:23761774

  4. Desktop chaotic systems: Intuition and visualization

    NASA Technical Reports Server (NTRS)

    Bright, Michelle M.; Melcher, Kevin J.; Qammar, Helen K.; Hartley, Tom T.

    1993-01-01

    This paper presents a dynamic study of the Wildwood Pendulum, a commercially available desktop system which exhibits a strange attractor. The purpose of studying this chaotic pendulum is twofold: to gain insight in the paradigmatic approach of modeling, simulating, and determining chaos in nonlinear systems; and to provide a desktop model of chaos as a visual tool. For this study, the nonlinear behavior of this chaotic pendulum is modeled, a computer simulation is performed, and an experimental performance is measured. An assessment of the pendulum in the phase plane shows the strange attractor. Through the use of a box-assisted correlation dimension methodology, the attractor dimension is determined for both the model and the experimental pendulum systems. Correlation dimension results indicate that the pendulum and the model are chaotic and their fractal dimensions are similar.

  5. Visual Support System for Report Distinctiveness Evaluation

    NASA Astrophysics Data System (ADS)

    Sunayama, Wataru; Kawaguchi, Toshiaki

    In recent years, as the Internet has grown, electronic reports have come to be used in educational organizations such as universities. Though reports written by hand must be evaluated by hand except for stereotype descriptions or numerical answers, electronic reports can be rated by computer. There are two major criteria in rating reports, correctness and distinctiveness. Correctness is rated by absolute criteria and distinctiveness is rated by relative criteria. Relative evaluation is difficult because raters should memorize all contents of submitted reports to provide objective rates. In addition, electronic data are easily copied or exchanged by students. This paper presents a report evaluation support system with which raters can compare each report and give objective rates for distinctiveness. This system evaluates each report by objective similarity criteria and visualizes them in a two-dimensional interface as the calculated distinctiveness order. Experimental results show the system is valid and effective for estimating associations between reports.

  6. 30 CFR 77.309 - Visual check of system equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Visual check of system equipment. 77.309 Section 77.309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Thermal Dryers § 77.309 Visual check of system equipment. Frequent visual checks shall...

  7. The lived experience of visual creative expression for young adult cancer survivors.

    PubMed

    Green, A R; Young, R A

    2015-09-01

    Engaging in visual creative expression individually and in a therapeutic setting can be a beneficial experience for cancer survivors; however, most research in this field has been conducted with older adults. The current study aimed to address this gap by utilising van Manen's hermeneutic phenomenology to answer the following question: 'What is the lived experience and meaning of visual creative expression for young adult cancer survivors?' Seven young adults, diagnosed with cancer between the ages of 18 and 35, were interviewed about creative expression experiences, which they engaged in individually and/or in a therapeutic setting. Data analysis included a thematic reflection, guided existential reflection, and a process of writing and rewriting. Two superordinate themes were identified: increased self-understanding and a healing experience. Seven subthemes were also identified and included the following: being in the flow, allowing the body to express itself, renegotiating control, changing one's environment, being seen, respect for art as a separate entity and giving back. Findings suggest that visual creative expression can be a meaningful experience for young adult cancer survivors, and that this experience espouses both similarities and differences from experiences of older adult survivors. Recommendations are made for future research, in addition to implications for practitioners.

  8. Rapid detection of visually provocative animals by preschool children and adults.

    PubMed

    Penkunas, Michael J; Coss, Richard G

    2013-04-01

    The ability to detect dangerous animals rapidly in complex landscapes has been historically important during human evolution. Previous research has shown that snake images are more readily detected than images of benign animals. To provide a stringent test of superior snake detection in preschool children and adults, Experiment 1 consisted of two parts using a touch-screen visual search task. Reaction times to detect different target snakes embedded in matrices of lizards were compared with reaction times to detect target lizards embedded in matrices of snakes. Experiment 2 compared the visual salience of lions with that of similarly colored antelopes. This experiment tested the prediction that historically dangerous felid predators would also engender rapid detection. Results from the two experiments revealed that both preschool children and adults located snakes and lions more quickly than their nonthreatening counterparts. Experiment 3 examined the ability of children and adults to distinguish between similar appearing cows and horses. Preschool children and adult men exhibited no reliable differences in detecting the two animal types. Adult women located horses reliably faster than cows, suggesting that visual biases for some animals can be acquired after childhood.

  9. Neuroanatomical affiliation visualization-interface system.

    PubMed

    Palombi, Olivier; Shin, Jae-Won; Watson, Charles; Paxinos, George

    2006-01-01

    A number of knowledge management systems have been developed to allow users to have access to large quantity of neuroanatomical data. The advent of three-dimensional (3D) visualization techniques allows users to interact with complex 3D object. In order to better understand the structural and functional organization of the brain, we present Neuroanatomical Affiliations Visualization-Interface System (NAVIS) as the original software to see brain structures and neuroanatomical affiliations in 3D. This version of NAVIS has made use of the fifth edition of "The Rat Brain in Stereotaxic coordinates" (Paxinos and Watson, 2005). The NAVIS development environment was based on the scripting language name Python, using visualization toolkit (VTK) as 3D-library and wxPython for the graphic user interface. The following manuscript is focused on the nucleus of the solitary tract (Sol) and the set of affiliated structures in the brain to illustrate the functionality of NAVIS. The nucleus of the Sol is the primary relay center of visceral and taste information, and consists of 14 distinct subnuclei that differ in cytoarchitecture, chemoarchitecture, connections, and function. In the present study, neuroanatomical projection data of the rat Sol were collected from selected literature in PubMed since 1975. Forty-nine identified projection data of Sol were inserted in NAVIS. The standard XML format used as an input for affiliation data allows NAVIS to update data online and/or allows users to manually change or update affiliation data. NAVIS can be extended to nuclei other than Sol.

  10. Intensive video gaming improves encoding speed to visual short-term memory in young male adults.

    PubMed

    Wilms, Inge L; Petersen, Anders; Vangkilde, Signe

    2013-01-01

    The purpose of this study was to measure the effect of action video gaming on central elements of visual attention using Bundesen's (1990) Theory of Visual Attention. To examine the cognitive impact of action video gaming, we tested basic functions of visual attention in 42 young male adults. Participants were divided into three groups depending on the amount of time spent playing action video games: non-players (<2h/month, N=12), casual players (4-8h/month, N=10), and experienced players (>15h/month, N=20). All participants were tested in three tasks which tap central functions of visual attention and short-term memory: a test based on the Theory of Visual Attention (TVA), an enumeration test and finally the Attentional Network Test (ANT). The results show that action video gaming does not seem to impact the capacity of visual short-term memory. However, playing action video games does seem to improve the encoding speed of visual information into visual short-term memory and the improvement does seem to depend on the time devoted to gaming. This suggests that intense action video gaming improves basic attentional functioning and that this improvement generalizes into other activities. The implications of these findings for cognitive rehabilitation training are discussed.

  11. Altered neuronal architecture and plasticity in the visual cortex of adult MMP-3-deficient mice.

    PubMed

    Aerts, Jeroen; Nys, Julie; Moons, Lieve; Hu, Tjing-Tjing; Arckens, Lutgarde

    2015-09-01

    Matrix metalloproteinases (MMPs) are Zn(2+)-dependent endopeptidases considered to be essential for normal brain development and neuroplasticity by modulating extracellular matrix proteins, receptors, adhesion molecules, growth factors and cytoskeletal proteins. Specifically, MMP-3 has recently been implicated in synaptic plasticity, hippocampus-dependent learning and neuronal development and migration in the cerebellum. However, the function(s) of this enzyme in the neocortex is understudied. Therefore, we explored the phenotypical characteristics of the neuronal architecture and the capacity for experience-dependent cortical plasticity in the visual cortex of adult MMP-3-deficient (MMP-3(-/-)) mice. Golgi-Cox stainings revealed a significant reduction in apical dendritic length and an increased number of apical obliques for layer V pyramidal neurons in the visual cortex of adult MMP-3(-/-) mice compared to wild-type (WT) animals. In addition, a significant upregulation of both phosphorylated and non-phosphorylated neurofilament protein (NF)-high, phosphorylated NF-medium, NF-low and α-internexin was detected in the visual cortex of MMP-3(-/-) mice. To assess the effect of MMP-3 deficiency on cortical plasticity, we monocularly enucleated adult MMP-3(-/-) mice and analyzed the reactivation of the contralateral visual cortex 7 weeks post-enucleation. In contrast to previous results in C57Bl/6J adult mice, activity remained confined to the binocular zone and did not expand into the monocular regions indicative for an aberrant open-eye potentiation. Permanent hypoactivity in the monocular cortex lateral and medial to V1 also indicated a lack of cross-modal plasticity. These observations demonstrate that genetic inactivation of MMP-3 has profound effects on the structural integrity and plasticity response of the visual cortex of adult mice.

  12. Visualization for understanding of neurodynamical systems.

    PubMed

    Duch, Włodzisław; Dobosz, Krzysztof

    2011-06-01

    Complex neurodynamical systems are quite difficult to analyze and understand. New type of plots are introduced to help in visualization of high-dimensional trajectories and show global picture of the phase space, including relations between basins of attractors. Color recurrence plots (RPs) display distances from each point on the trajectory to all other points in a two-dimensional matrix. Fuzzy Symbolic Dynamics (FSD) plots enhance this information mapping the whole trajectory to two or three dimensions. Each coordinate is defined by the value of a fuzzy localized membership function, optimized to visualize interesting features of the dynamics, showing to which degree a point on the trajectory belongs to some neighborhood. The variance of the trajectory within the attraction basin plotted against the variance of the synaptic noise provides information about sizes and shapes of these basins. Plots that use color to show the distance between each trajectory point and a larger number of selected reference points (for example centers of attractor basins) are also introduced. Activity of 140 neurons in the semantic layer of dyslexia model implemented in the Emergent neural simulator is analyzed in details showing different aspects of neurodynamics that may be understood in this way. Influence of connectivity and various neural properties on network dynamics is illustrated using visualization techniques. A number of interesting conclusions about cognitive neurodynamics of lexical concept activations are drawn. Changing neural accommodation parameters has very strong influence on the dwell time of the trajectories. This may be linked to attention deficits disorders observed in autism in case of strong enslavement, and to ADHD-like behavior in case of weak enslavement.

  13. A neurochemical signature of visual recovery after extrastriate cortical damage in the adult cat.

    PubMed

    Huxlin, Krystel R; Williams, Jennifer M; Price, Tracy

    2008-05-01

    In adult cats, damage to the extrastriate visual cortex on the banks of the lateral suprasylvian (LS) sulcus causes severe deficits in motion perception that can recover as a result of intensive direction discrimination training. The fact that recovery is restricted to trained visual field locations suggests that the neural circuitry of early visual cortical areas, with their tighter retinotopy, may play an important role in attaining perceptual improvements after damage to higher level visual cortex. The present study tests this hypothesis by comparing the manner in which excitatory and inhibitory components of the supragranular circuitry in an early visual cortical area (area 18) are affected by LS lesions and postlesion training. First, the proportion of LS-projecting pyramidal cells as well as calbindin- and parvalbumin-positive interneurons expressing each of the four AMPA receptor subunits was estimated in layers II and III of area 18 in intact animals. The degree to which LS lesions and visual retraining altered these expression patterns was then assessed. Both LS-projecting pyramidal cells and inhibitory interneurons exhibited long-term, differential reductions in the expression of glutamate receptor (GluR)1, -2, -2/3, and -4 following LS lesions. Intensive visual training post lesion restored normal AMPAR subunit expression in all three cell-types examined. Furthermore, for LS-projecting and calbindin-positive neurons, this restoration occurred only in portions of the ipsi-lesional area 18 representing trained visual field locations. This supports our hypothesis that stimulation of early visual cortical areas-in this case, area 18-by training is an important factor in restoring visual perception after permanent damage to LS cortex.

  14. Visual Turing test for computer vision systems

    PubMed Central

    Geman, Donald; Geman, Stuart; Hallonquist, Neil; Younes, Laurent

    2015-01-01

    Today, computer vision systems are tested by their accuracy in detecting and localizing instances of objects. As an alternative, and motivated by the ability of humans to provide far richer descriptions and even tell a story about an image, we construct a “visual Turing test”: an operator-assisted device that produces a stochastic sequence of binary questions from a given test image. The query engine proposes a question; the operator either provides the correct answer or rejects the question as ambiguous; the engine proposes the next question (“just-in-time truthing”). The test is then administered to the computer-vision system, one question at a time. After the system’s answer is recorded, the system is provided the correct answer and the next question. Parsing is trivial and deterministic; the system being tested requires no natural language processing. The query engine employs statistical constraints, learned from a training set, to produce questions with essentially unpredictable answers—the answer to a question, given the history of questions and their correct answers, is nearly equally likely to be positive or negative. In this sense, the test is only about vision. The system is designed to produce streams of questions that follow natural story lines, from the instantiation of a unique object, through an exploration of its properties, and on to its relationships with other uniquely instantiated objects. PMID:25755262

  15. The emotional blink: adult age differences in visual attention to emotional information.

    PubMed

    Langley, Linda K; Rokke, Paul D; Stark, Atiana C; Saville, Alyson L; Allen, Jaryn L; Bagne, Angela G

    2008-12-01

    To assess age differences in attention-emotion interactions, the authors asked young adults (ages 18-33 years) and older adults (ages 60-80 years) to identify target words in a rapid serial visual presentation (RSVP) task. The second of two target words was neutral or emotional in content (positive in Experiment 1, negative in Experiment 2). In general, the ability to identify targets from a word stream declined with age. Age differences specific to the attentional blink were greatly reduced when baseline detection accuracy was equated between groups. With regard to emotion effects, older adults showed enhanced identification of both positive and negative words relative to neutral words, whereas young adults showed enhanced identification of positive words and reduced identification of negative words. Together these findings suggest that the nature of attention-emotion interactions changes with age, but there was little support for a motivational shift consistent with emotional regulation goals at an early stage of cognitive processing.

  16. The Emotional Blink: Adult Age Differences in Visual Attention to Emotional Information

    PubMed Central

    Langley, Linda K.; Rokke, Paul D.; Stark, Atiana C.; Saville, Alyson L.; Allen, Jaryn L.; Bagne, Angela G.

    2008-01-01

    To assess age differences in attention-emotion interactions, younger adults (ages 18–33 yrs) and older adults (ages 60–80 yrs) identified target words in a rapid serial visual presentation (RSVP) task. The second of two target words was neutral or emotional in content (positive in Experiment 1, negative in Experiment 2). In general, the ability to identify targets from a word stream declined with age. Age differences specific to the attentional blink were greatly reduced when baseline detection accuracy was equated between groups. With regard to emotion effects, older adults showed enhanced identification of both positive and negative words relative to neutral words, whereas younger adults showed enhanced identification of positive words and reduced identification of negative words. Together these findings suggest that the nature of attention-emotion interactions changes with age, but there was little support for a motivational shift consistent with emotional regulation goals at an early stage of cognitive processing. PMID:19140657

  17. Sodern visualization system (SVS) in command rooms

    NASA Astrophysics Data System (ADS)

    Doittau, F.-X.; Huriet, J. R.; Tissot, M.

    The enhancement of the Sodern Visualization System, originally designed for live TV display in motion picture theaters, to make it suitable for command rooms, is described. At the request of the French Military Administration and the U.S. Air Force, resolution and speed have been significantly improved to enable simulation of air combat. To display 90 characters per line, and then extend this to 120 characters per line, required experimental study leading to the design of reshaped characters. Optimizing color contrast by providing a dark blue background improved readability still more. Finally, the use of a Titus light valve which includes a solid -state crystal target permits very comfortable viewing due to the absence of flicker and line structure.

  18. A Small Motor Cortex Lesion Abolished Ocular Dominance Plasticity in the Adult Mouse Primary Visual Cortex and Impaired Experience-Dependent Visual Improvements.

    PubMed

    Pielecka-Fortuna, Justyna; Kalogeraki, Evgenia; Greifzu, Franziska; Löwel, Siegrid

    2015-01-01

    It was previously shown that a small lesion in the primary somatosensory cortex (S1) prevented both cortical plasticity and sensory learning in the adult mouse visual system: While 3-month-old control mice continued to show ocular dominance (OD) plasticity in their primary visual cortex (V1) after monocular deprivation (MD), age-matched mice with a small photothrombotically induced (PT) stroke lesion in S1, positioned at least 1 mm anterior to the anterior border of V1, no longer expressed OD-plasticity. In addition, in the S1-lesioned mice, neither the experience-dependent increase of the spatial frequency threshold ("visual acuity") nor of the contrast threshold ("contrast sensitivity") of the optomotor reflex through the open eye was present. To assess whether these plasticity impairments can also occur if a lesion is placed more distant from V1, we tested the effect of a PT-lesion in the secondary motor cortex (M2). We observed that mice with a small M2-lesion restricted to the superficial cortical layers no longer expressed an OD-shift towards the open eye after 7 days of MD in V1 of the lesioned hemisphere. Consistent with previous findings about the consequences of an S1-lesion, OD-plasticity in V1 of the nonlesioned hemisphere of the M2-lesioned mice was still present. In addition, the experience-dependent improvements of both visual acuity and contrast sensitivity of the open eye were severely reduced. In contrast, sham-lesioned mice displayed both an OD-shift and improvements of visual capabilities of their open eye. To summarize, our data indicate that even a very small lesion restricted to the superficial cortical layers and more than 3mm anterior to the anterior border of V1 compromised V1-plasticity and impaired learning-induced visual improvements in adult mice. Thus both plasticity phenomena cannot only depend on modality-specific and local nerve cell networks but are clearly influenced by long-range interactions even from distant brain regions.

  19. A Small Motor Cortex Lesion Abolished Ocular Dominance Plasticity in the Adult Mouse Primary Visual Cortex and Impaired Experience-Dependent Visual Improvements

    PubMed Central

    Pielecka-Fortuna, Justyna; Kalogeraki, Evgenia; Greifzu, Franziska; Löwel, Siegrid

    2015-01-01

    It was previously shown that a small lesion in the primary somatosensory cortex (S1) prevented both cortical plasticity and sensory learning in the adult mouse visual system: While 3-month-old control mice continued to show ocular dominance (OD) plasticity in their primary visual cortex (V1) after monocular deprivation (MD), age-matched mice with a small photothrombotically induced (PT) stroke lesion in S1, positioned at least 1 mm anterior to the anterior border of V1, no longer expressed OD-plasticity. In addition, in the S1-lesioned mice, neither the experience-dependent increase of the spatial frequency threshold (“visual acuity”) nor of the contrast threshold (“contrast sensitivity”) of the optomotor reflex through the open eye was present. To assess whether these plasticity impairments can also occur if a lesion is placed more distant from V1, we tested the effect of a PT-lesion in the secondary motor cortex (M2). We observed that mice with a small M2-lesion restricted to the superficial cortical layers no longer expressed an OD-shift towards the open eye after 7 days of MD in V1 of the lesioned hemisphere. Consistent with previous findings about the consequences of an S1-lesion, OD-plasticity in V1 of the nonlesioned hemisphere of the M2-lesioned mice was still present. In addition, the experience-dependent improvements of both visual acuity and contrast sensitivity of the open eye were severely reduced. In contrast, sham-lesioned mice displayed both an OD-shift and improvements of visual capabilities of their open eye. To summarize, our data indicate that even a very small lesion restricted to the superficial cortical layers and more than 3mm anterior to the anterior border of V1 compromised V1-plasticity and impaired learning-induced visual improvements in adult mice. Thus both plasticity phenomena cannot only depend on modality-specific and local nerve cell networks but are clearly influenced by long-range interactions even from distant brain

  20. Effective Learner-Centered Strategies for Teaching Adults: Using Visual Media to Engage the Adult Learner

    ERIC Educational Resources Information Center

    Myers, Dennis R.; Sykes, Catherine; Myers, Scott

    2008-01-01

    This article offers practical guidance for educators as they prepare specialists to enhance the lives and communities of older persons through the strategic use of visual media in age-related courses. Advantages and disadvantages of this learning innovation are provided as well as seven approaches for enriching instruction. Resources are included…

  1. Regulating critical period plasticity: insight from the visual system to fear circuitry for therapeutic interventions.

    PubMed

    Nabel, Elisa M; Morishita, Hirofumi

    2013-01-01

    Early temporary windows of heightened brain plasticity called critical periods developmentally sculpt neural circuits and contribute to adult behavior. Regulatory mechanisms of visual cortex development - the preeminent model of experience-dependent critical period plasticity-actively limit adult plasticity and have proved fruitful therapeutic targets to reopen plasticity and rewire faulty visual system connections later in life. Interestingly, these molecular mechanisms have been implicated in the regulation of plasticity in other functions beyond vision. Applying mechanistic understandings of critical period plasticity in the visual cortex to fear circuitry may provide a conceptual framework for developing novel therapeutic tools to mitigate aberrant fear responses in post traumatic stress disorder. In this review, we turn to the model of experience-dependent visual plasticity to provide novel insights for the mechanisms regulating plasticity in the fear system. Fear circuitry, particularly fear memory erasure, also undergoes age-related changes in experience-dependent plasticity. We consider the contributions of molecular brakes that halt visual critical period plasticity to circuitry underlying fear memory erasure. A major molecular brake in the visual cortex, perineuronal net formation, recently has been identified in the development of fear systems that are resilient to fear memory erasure. The roles of other molecular brakes, myelin-related Nogo receptor signaling and Lynx family proteins - endogenous inhibitors for nicotinic acetylcholine receptor, are explored in the context of fear memory plasticity. Such fear plasticity regulators, including epigenetic effects, provide promising targets for therapeutic interventions.

  2. Visual stimulation enhances auditory processing in 3-month-old infants and adults.

    PubMed

    Hyde, Daniel C; Jones, Blake L; Porter, Chris L; Flom, Ross

    2010-03-01

    Behavioral work demonstrates human infants are sensitive to a host of intersensory properties and this sensitivity promotes early learning and memory. However, little is known regarding the neural basis of this ability in infants. Using event-related potentials (ERPs) with infants and adults, we show that during passive viewing auditory evoked brain responses are increased with the presence of simultaneous visual stimulation. Results converge with previous adult neuroimaging studies, single-cell recordings in nonhuman animals, and behavioral studies with human infants to provide evidence for an elevated status of multisensory stimulation in infancy. Furthermore, these results may provide a neural marker of multisensory audio-visual processing in infants that can be used to test developmental theories of how information is integrated across the senses to form a unitary perception of the world.

  3. Visual-Somatosensory Integration is Linked to Physical Activity Level in Older Adults.

    PubMed

    Mahoney, Jeannette R; Dumas, Kristina; Holtzer, Roee

    2015-01-01

    Studies examining multisensory integration (MSI) in aging consistently demonstrate greater reaction time (RT) facilitation in old compared to young adults, but often fail to determine the utility of MSI. The aim of the current experiment was to further elucidate the utility of MSI in aging by determining its relationship to physical activity level. 147 non-demented older adults (mean age 77 years; 57% female) participated. Participants were instructed to make speeded responses to visual, somatosensory, and visual-somatosensory (VS) stimuli. Depending on the magnitude of the individuals' RT facilitation, participants were classified into a MSI or NO MSI group. Physical activity was assessed using a validated physical activity scale. As predicted, RTs to VS stimuli were significantly shorter than those elicited to constituent unisensory conditions. Multisensory RT facilitation was a significant predictor of total number of physical activity days per month, with individuals in the NO MSI group reporting greater engagement in physical activities compared to those requiring greater RT facilitation.

  4. A Visualization System for Interactive Exploration of the Cardiac Anatomy.

    PubMed

    Zhang, Lei; Wang, Kuanquan; Yang, Fei; Lu, Wenjing; Wang, Kechao; Zhang, Yue; Liang, Xiaoqing; Han, Dongchen; Zhu, Ying Julie

    2016-06-01

    Because of the complex and fine structure, visualization of the heart still remains a challenging task, which makes it an active research topic. In this paper, we present a visualization system for medical data, which takes advantage of the recent graphics processing unit (GPU) and can provide real-time cardiac visualization. This work focuses on investigating the anatomical structure visualization of the human heart, which is fundamental to the cardiac visualization, medical training and diagnosis assistance. Several state-of-the-art cardiac visualization methods are integrated into the proposed system and a task specified visualization method is proposed. In addition, auxiliary tools are provided to generate user specified visualization results. The contributions of our work lie in two-fold: for doctors and medical staff, the system can provide task specified visualization with interactive visualization tools; for researchers, the proposed platform can serve as a baseline for comparing different rendering methods and can easily incorporate new rendering methods. Experimental results show that the proposed system can provide favorable cardiac visualization results in terms of both effectiveness and efficiency.

  5. Preserving visual saliency in image to sound substitution systems

    NASA Astrophysics Data System (ADS)

    Ancuti, Codruta O.; Ancuti, Cosmin; Bekaert, Philippe

    2009-02-01

    Color plays a significant role in the scene interpretation in terms of visual perception. Numerous visual substitution systems deal with grayscale images disregarding this information from original image. Visually percept color-based details often fade due to the grayscale conversion and that can mislead the overall comprehension of the considered scene. We present a decolorization method that considers color contrast and preserve color saliency after transformation. We exploit this model to enhance the perception of visually disable persons over the interpreted images by the substitution system. The results demonstrate that our enhance system is capable to improves the overall scene interpretation in comparison with similar substitution system.

  6. Neurogenesis in the adult peripheral nervous system.

    PubMed

    Czaja, Krzysztof; Fornaro, Michele; Geuna, Stefano

    2012-05-15

    Most researchers believe that neurogenesis in mature mammals is restricted only to the subgranular zone of the dentate gyrus and the subventricular zone of the lateral ventricle in the central nervous system. In the peripheral nervous system, neurogenesis is thought to be active only during prenatal development, with the exception of the olfactory neuroepithelium. However, sensory ganglia in the adult peripheral nervous system have been reported to contain precursor cells that can proliferate in vitro and be induced to differentiate into neurons. The occurrence of insult-induced neurogenesis, which has been reported by several investigators in the brain, is limited to a few recent reports for the peripheral nervous system. These reports suggest that damage to the adult nervous system induces mechanisms similar to those that control the generation of new neurons during prenatal development. Understanding conditions under which neurogenesis can be induced in physiologically non-neurogenic regions in adults is one of the major challenges for developing therapeutic strategies to repair neurological damage. However, the induced neurogenesis in the peripheral nervous system is still largely unexplored. This review presents the history of research on adult neurogenesis in the peripheral nervous system, which dates back more than 100 years and reveals the evidence on the under estimated potential for generation of new neurons in the adult peripheral nervous system.

  7. The reliability of two visual motor integration tests used with healthy adults.

    PubMed

    Brown, Ted; Chinner, Alexandra; Stagnitti, Karen

    2010-10-01

    ABSTRACT Occupational therapists often assess the visual motor integration (VMI) skills of children, adults, and the elderly, which are parts of the Body Functions and Structures of the International Classification of Functioning, Disability and Health. Objective. As it is imperative that therapists use tests and measures with strong psychometric properties, this study aims to examine the reliability of two VMI tests used with adults. Method. Sixty-one healthy adults, 18 males and 43 females, with an average age of 31.82 years, completed the Developmental Test of Visual Motor Integration (DTVMI) and the Full Range Test of Visual Motor Integration (FRTVMI). The Cronbach's alpha coefficient was used to examine the tests' internal consistency, while the Spearman's rho correlation was used to evaluate the test-retest reliability, intrarater reliability, and interrater reliability of the two VMI tests. Results. The Cronbach's alpha coefficient for the DTVMI and FRTVMI was 0.66 and 0.80, respectively. The test-retest reliability coefficient was 0.77 (p < .001) for the DTVMI and 0.61 (p < .001) for the FRTVMI. The interrater reliability correlation was significant for both DTVMI at 0.79 (p < .001) and FRTVMI at 0.80 (p < .001). The DTVMI intrarater reliability correlation result was 0.95 (p < .001) and the FRTVMI at 0.87 (p < .001). Conclusion. Overall, the DTVMI and the FRTVMI exhibited moderate to high levels of reliability when used with a sample of healthy adults. Both VMI tests appear to exhibit reasonable levels of reliability and are recommended for use with adults and the elderly.

  8. Integration of audio-visual information for spatial decisions in children and adults.

    PubMed

    Nardini, Marko; Bales, Jennifer; Mareschal, Denis

    2016-09-01

    In adults, decisions based on multisensory information can be faster and/or more accurate than those relying on a single sense. However, this finding varies significantly across development. Here we studied speeded responding to audio-visual targets, a key multisensory function whose development remains unclear. We found that when judging the locations of targets, children aged 4 to 12 years and adults had faster and less variable response times given auditory and visual information together compared with either alone. Comparison of response time distributions with model predictions indicated that children at all ages were integrating (pooling) sensory information to make decisions but that both the overall speed and the efficiency of sensory integration improved with age. The evidence for pooling comes from comparison with the predictions of Miller's seminal 'race model', as well as with a major recent extension of this model and a comparable 'pooling' (coactivation) model. The findings and analyses can reconcile results from previous audio-visual studies, in which infants showed speed gains exceeding race model predictions in a spatial orienting task (Neil et al., 2006) but children below 7 years did not in speeded reaction time tasks (e.g. Barutchu et al., 2009). Our results provide new evidence for early and sustained abilities to integrate visual and auditory signals for spatial localization from a young age.

  9. A survey of visualization systems for network security.

    PubMed

    Shiravi, Hadi; Shiravi, Ali; Ghorbani, Ali A

    2012-08-01

    Security Visualization is a very young term. It expresses the idea that common visualization techniques have been designed for use cases that are not supportive of security-related data, demanding novel techniques fine tuned for the purpose of thorough analysis. Significant amount of work has been published in this area, but little work has been done to study this emerging visualization discipline. We offer a comprehensive review of network security visualization and provide a taxonomy in the form of five use-case classes encompassing nearly all recent works in this area. We outline the incorporated visualization techniques and data sources and provide an informative table to display our findings. From the analysis of these systems, we examine issues and concerns regarding network security visualization and provide guidelines and directions for future researchers and visual system developers.

  10. Cascaded Effects of Spatial Adaptation in the Early Visual System

    PubMed Central

    Dhruv, Neel T.; Carandini, Matteo

    2014-01-01

    Summary Virtually all stages of the visual system exhibit adaptation: neurons adjust their responses based on the recent stimulus history. While some of these adjustments occur at specific stages, others may be inherited from earlier stages. How do adaptation effects cascade along the visual system? We measured spatially selective adaptation at two successive stages in the mouse visual system: visual thalamus (LGN) and primary visual cortex (V1). This form of adaptation affected both stages but in drastically different ways: in LGN it only changed response gain, while in V1 it also shifted spatial tuning away from the adaptor. These effects, however, are reconciled by a simple model whereby V1 neurons summate LGN inputs with a fixed, unadaptable weighting profile. These results indicate that adaptation effects cascade through the visual system, that this cascading can shape selectivity, and that the rules of integration from one stage to the next are not themselves adaptable. PMID:24507190

  11. Latitudinal variation in light levels drives human visual system size.

    PubMed

    Pearce, Eiluned; Dunbar, Robin

    2012-02-23

    Ambient light levels influence visual system size in birds and primates. Here, we argue that the same is true for humans. Light levels, in terms of both the amount of light hitting the Earth's surface and day length, decrease with increasing latitude. We demonstrate a significant positive relationship between absolute latitude and human orbital volume, an index of eyeball size. Owing to tight scaling between visual system components, this will translate into enlarged visual cortices at higher latitudes. We also show that visual acuity measured under full-daylight conditions is constant across latitudes, indicating that selection for larger visual systems has mitigated the effect of reduced ambient light levels. This provides, to our knowledge, the first support that light levels drive intraspecific variation in visual system size in the human population.

  12. Cascaded effects of spatial adaptation in the early visual system.

    PubMed

    Dhruv, Neel T; Carandini, Matteo

    2014-02-05

    Virtually all stages of the visual system exhibit adaptation: neurons adjust their responses based on the recent stimulus history. While some of these adjustments occur at specific stages, others may be inherited from earlier stages. How do adaptation effects cascade along the visual system? We measured spatially selective adaptation at two successive stages in the mouse visual system: visual thalamus (LGN) and primary visual cortex (V1). This form of adaptation affected both stages but in drastically different ways: in LGN it only changed response gain, while in V1 it also shifted spatial tuning away from the adaptor. These effects, however, are reconciled by a simple model whereby V1 neurons summate LGN inputs with a fixed, unadaptable weighting profile. These results indicate that adaptation effects cascade through the visual system, that this cascading can shape selectivity, and that the rules of integration from one stage to the next are not themselves adaptable.

  13. Computer systems and methods for visualizing data

    DOEpatents

    Stolte, Chris; Hanrahan, Patrick

    2010-07-13

    A method for forming a visual plot using a hierarchical structure of a dataset. The dataset comprises a measure and a dimension. The dimension consists of a plurality of levels. The plurality of levels form a dimension hierarchy. The visual plot is constructed based on a specification. A first level from the plurality of levels is represented by a first component of the visual plot. A second level from the plurality of levels is represented by a second component of the visual plot. The dataset is queried to retrieve data in accordance with the specification. The data includes all or a portion of the dimension and all or a portion of the measure. The visual plot is populated with the retrieved data in accordance with the specification.

  14. Computer systems and methods for visualizing data

    DOEpatents

    Stolte, Chris; Hanrahan, Patrick

    2013-01-29

    A method for forming a visual plot using a hierarchical structure of a dataset. The dataset comprises a measure and a dimension. The dimension consists of a plurality of levels. The plurality of levels form a dimension hierarchy. The visual plot is constructed based on a specification. A first level from the plurality of levels is represented by a first component of the visual plot. A second level from the plurality of levels is represented by a second component of the visual plot. The dataset is queried to retrieve data in accordance with the specification. The data includes all or a portion of the dimension and all or a portion of the measure. The visual plot is populated with the retrieved data in accordance with the specification.

  15. Potentiation of the early visual response to learned danger signals in adults and adolescents

    PubMed Central

    Howsley, Philippa; Jordan, Jeff; Johnston, Pat

    2015-01-01

    The reinforcing effects of aversive outcomes on avoidance behaviour are well established. However, their influence on perceptual processes is less well explored, especially during the transition from adolescence to adulthood. Using electroencephalography, we examined whether learning to actively or passively avoid harm can modulate early visual responses in adolescents and adults. The task included two avoidance conditions, active and passive, where two different warning stimuli predicted the imminent, but avoidable, presentation of an aversive tone. To avoid the aversive outcome, participants had to learn to emit an action (active avoidance) for one of the warning stimuli and omit an action for the other (passive avoidance). Both adults and adolescents performed the task with a high degree of accuracy. For both adolescents and adults, increased N170 event-related potential amplitudes were found for both the active and the passive warning stimuli compared with control conditions. Moreover, the potentiation of the N170 to the warning stimuli was stable and long lasting. Developmental differences were also observed; adolescents showed greater potentiation of the N170 component to danger signals. These findings demonstrate, for the first time, that learned danger signals in an instrumental avoidance task can influence early visual sensory processes in both adults and adolescents. PMID:24652856

  16. Visual and Spatial Mental Imagery: Dissociable Systems of Representation.

    DTIC Science & Technology

    1987-08-07

    between vistiql and spatial representations of visual stimuli in perception. The concept of "two cortical visual systems." Ungeleider and Mishkin (1982...Pohl. 1973: Iwai & Mishkin . 1968: Brody & Pribram. 197Rp hq,,, observed a marked contrast between the effects of parietal and temporal lesions in vlculI...between different forms, patterns and objects. Ungeleider and Mishkin called the system that represents visual appearance. located in the temporal

  17. Video game training to improve selective visual attention in older adults.

    PubMed

    Belchior, Patrícia; Marsiske, Michael; Sisco, Shannon M; Yam, Anna; Bavelier, Daphne; Ball, Karlene; Mann, William C

    2013-07-01

    The current study investigated the effect of video game training on older adult's useful field of view performance (the UFOV® test). Fifty-eight older adult participants were randomized to receive practice with the target action game (Medal of Honor), a placebo control arcade game (Tetris), a clinically validated UFOV training program, or into a no contact control group. Examining pretest-posttest change in selective visual attention, the UFOV improved significantly more than the game groups; all three intervention groups improved significantly more than no-contact controls. There was a lack of difference between the two game conditions, differing from findings with younger adults. Discussion considers whether games posing less challenge might still be effective interventions for elders, and whether optimal training dosages should be higher.

  18. A knowledge based system for scientific data visualization

    NASA Technical Reports Server (NTRS)

    Senay, Hikmet; Ignatius, Eve

    1992-01-01

    A knowledge-based system, called visualization tool assistant (VISTA), which was developed to assist scientists in the design of scientific data visualization techniques, is described. The system derives its knowledge from several sources which provide information about data characteristics, visualization primitives, and effective visual perception. The design methodology employed by the system is based on a sequence of transformations which decomposes a data set into a set of data partitions, maps this set of partitions to visualization primitives, and combines these primitives into a composite visualization technique design. Although the primary function of the system is to generate an effective visualization technique design for a given data set by using principles of visual perception the system also allows users to interactively modify the design, and renders the resulting image using a variety of rendering algorithms. The current version of the system primarily supports visualization techniques having applicability in earth and space sciences, although it may easily be extended to include other techniques useful in other disciplines such as computational fluid dynamics, finite-element analysis and medical imaging.

  19. Web Enabled Collaborative Climate Visualization in the Earth System Grid

    SciTech Connect

    Kendall, Wesley; Glatter, Markus; Huang, Jian; Hoffman, Forrest M; Bernholdt, David E

    2008-01-01

    The recent advances in high performance computing, storage and networking technologies have enabled fundamental changes in current climate research. While sharing datasets and results is already common practice in climate modeling, direct sharing of the analysis and visualization process is also becoming feasible. We report our efforts to develop a capability, coupled with the Earth System Grid (ESG), for sharing an entire executable workspace of visualization among collaborators. Evolutionary history of visualizations of research findings can also be captured and shared. The data intensive nature of the visualization system requires using several advanced techniques of visualization and parallel computing. With visualization clients implemented through standard web browsers, however, the ensuing complexity is made transparent to end-users. We demonstrate the efficacy of our system using cutting edge climate datasets.

  20. 40 CFR 202.22 - Visual exhaust system inspection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Visual exhaust system inspection. 202.22 Section 202.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE... Standards § 202.22 Visual exhaust system inspection. No motor carrier subject to these regulations...

  1. Real-Time Visualization System for Computational Offloading

    DTIC Science & Technology

    2015-01-01

    Real- Time Visualization System for Computational Offloading by Bryan Dawson and David L Doria ARL-TN-0655 January 2015... Time Visualization System for Computational Offloading Bryan Dawson Oak Ridge Institute for Science and Education David L Doria Computational...hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and

  2. Development of the Visual System and Implications for Early Intervention.

    ERIC Educational Resources Information Center

    Glass, Penny

    2002-01-01

    This article summarizes the early development of the visual system within the context of the other sensory systems and preterm birth and relates this information to early intervention. Retinopathy of prematurely, ocular defects, cortical visual impairment and potential impact of the neonatal intensive care unit environment are discussed. (Contains…

  3. TOPICAL REVIEW: Prosthetic interfaces with the visual system: biological issues

    NASA Astrophysics Data System (ADS)

    Cohen, Ethan D.

    2007-06-01

    The design of effective visual prostheses for the blind represents a challenge for biomedical engineers and neuroscientists. Significant progress has been made in the miniaturization and processing power of prosthesis electronics; however development lags in the design and construction of effective machine brain interfaces with visual system neurons. This review summarizes what has been learned about stimulating neurons in the human and primate retina, lateral geniculate nucleus and visual cortex. Each level of the visual system presents unique challenges for neural interface design. Blind patients with the retinal degenerative disease retinitis pigmentosa (RP) are a common population in clinical trials of visual prostheses. The visual performance abilities of normals and RP patients are compared. To generate pattern vision in blind patients, the visual prosthetic interface must effectively stimulate the retinotopically organized neurons in the central visual field to elicit patterned visual percepts. The development of more biologically compatible methods of stimulating visual system neurons is critical to the development of finer spatial percepts. Prosthesis electrode arrays need to adapt to different optimal stimulus locations, stimulus patterns, and patient disease states.

  4. The Contribution of Visual and Vestibular Information to Spatial Orientation by 6- to 14-Month-Old Infants and Adults

    ERIC Educational Resources Information Center

    Bremner, J. Gavin; Hatton, Fran; Foster, Kirsty A.; Mason, Uschi

    2011-01-01

    Although there is much research on infants' ability to orient in space, little is known regarding the information they use to do so. This research uses a rotating room to evaluate the relative contribution of visual and vestibular information to location of a target following bodily rotation. Adults responded precisely on the basis of visual flow…

  5. Visualization System Requirements for Data Processing Pipeline Design and Optimization.

    PubMed

    von Landesberger, Tatiana; Fellner, Dieter; Ruddle, Roy

    2016-08-25

    The rising quantity and complexity of data creates a need to design and optimize data processing pipelines - the set of data processing steps, parameters and algorithms that perform operations on the data. Visualization can support this process but, although there are many examples of systems for visual parameter analysis, there remains a need to systematically assess users' requirements and match those requirements to exemplar visualization methods. This article presents a new characterization of the requirements for pipeline design and optimization. This characterization is based on both a review of the literature and first-hand assessment of eight application case studies. We also match these requirements with exemplar functionality provided by existing visualization tools. Thus, we provide end-users and visualization developers with a way of identifying functionality that addresses data processing problems in an application. We also identify seven future challenges for visualization research that are not met by the capabilities of today's systems.

  6. Spontaneous Strategy Use Protects Against Visual Working Memory Deficits in Older Adults Infected with HIV

    PubMed Central

    Woods, Steven Paul; Weber, Erica; Cameron, Marizela V.; Dawson, Matthew S.; Delano-Wood, Lisa; Bondi, Mark W.; Grant, Igor

    2010-01-01

    Recent studies suggest that older human immunodeficiency virus (HIV)-infected adults are at particular risk for HIV-associated neurocognitive disorders (HAND), including dementia. Deficits in attention/working memory are posited to play a central role in the development of HAND among older adults. The aim of the present study was to examine the possible protective benefits of spontaneous strategy use during a visual working memory task in 46 older and 42 younger adults infected with HIV. Results revealed a significant interaction between age and strategy use, with older adults who used a meta-cognitive strategy demonstrating superior working memory performance versus non-strategy users. This effect was not observed in the younger HIV-infected sample and was not better explained by possible confounding factors, such as education, comorbid medical conditions, or HIV disease severity. Within the older group, strategy use was associated with better executive functions and higher estimated verbal intelligence. Findings from this study suggest that working memory declines in older HIV-infected adults are moderated by the use of higher-level mnemonic strategies and may inform cognitive neurorehabilitation efforts to improve cognitive and everyday functioning outcomes in older persons living with HIV infection. PMID:20876195

  7. Spontaneous strategy use protects against visual working memory deficits in older adults infected with HIV.

    PubMed

    Woods, Steven Paul; Weber, Erica; Cameron, Marizela V; Dawson, Matthew S; Delano-Wood, Lisa; Bondi, Mark W; Grant, Igor

    2010-12-01

    Recent studies suggest that older human immunodeficiency virus (HIV)-infected adults are at particular risk for HIV-associated neurocognitive disorders (HAND), including dementia. Deficits in attention/working memory are posited to play a central role in the development of HAND among older adults. The aim of the present study was to examine the possible protective benefits of spontaneous strategy use during a visual working memory task in 46 older and 42 younger adults infected with HIV. Results revealed a significant interaction between age and strategy use, with older adults who used a meta-cognitive strategy demonstrating superior working memory performance versus non-strategy users. This effect was not observed in the younger HIV-infected sample and was not better explained by possible confounding factors, such as education, comorbid medical conditions, or HIV disease severity. Within the older group, strategy use was associated with better executive functions and higher estimated verbal intelligence. Findings from this study suggest that working memory declines in older HIV-infected adults are moderated by the use of higher-level mnemonic strategies and may inform cognitive neurorehabilitation efforts to improve cognitive and everyday functioning outcomes in older persons living with HIV infection.

  8. Test report, earth orbiter teleoperator visual system evaluation program

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, M.; Shields, N. L., Jr.; Malone, T. B.

    1974-01-01

    Work carried out to identify human performance requirements for remotely manned system is reported. Specifically, an evaluation was made of the human visual system. Data cover distance estimation 4, solid target alignment 2, motion detection 1, and motion detection 2.

  9. Socio-cognitive profiles for visual learning in young and older adults

    PubMed Central

    Christian, Julie; Goldstone, Aimee; Kuai, Shu-Guang; Chin, Wynne; Abrams, Dominic; Kourtzi, Zoe

    2015-01-01

    It is common wisdom that practice makes perfect; but why do some adults learn better than others? Here, we investigate individuals’ cognitive and social profiles to test which variables account for variability in learning ability across the lifespan. In particular, we focused on visual learning using tasks that test the ability to inhibit distractors and select task-relevant features. We tested the ability of young and older adults to improve through training in the discrimination of visual global forms embedded in a cluttered background. Further, we used a battery of cognitive tasks and psycho-social measures to examine which of these variables predict training-induced improvement in perceptual tasks and may account for individual variability in learning ability. Using partial least squares regression modeling, we show that visual learning is influenced by cognitive (i.e., cognitive inhibition, attention) and social (strategic and deep learning) factors rather than an individual’s age alone. Further, our results show that independent of age, strong learners rely on cognitive factors such as attention, while weaker learners use more general cognitive strategies. Our findings suggest an important role for higher-cognitive circuits involving executive functions that contribute to our ability to improve in perceptual tasks after training across the lifespan. PMID:26113820

  10. Visual ability and searching behavior of adult Laricobius nigrinus, a hemlock woolly adelgid predator.

    PubMed

    Mausel, D L; Salom, S M; Kok, L T

    2011-01-01

    Very little is known about the searching behavior and sensory cues that Laricobius spp. (Coleoptera: Derodontidae) predators use to locate suitable habitats and prey, which limits our ability to collect and monitor them for classical biological control of adelgids (Hemiptera: Adelgidae). The aim of this study was to examine the visual ability and the searching behavior of newly emerged L. nigrinus Fender, a host-specific predator of the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Phylloxeroidea: Adelgidae). In a laboratory bioassay, individual adults attempting to locate an uninfested eastern hemlock seedling under either light or dark conditions were observed in an arena. In another bioassay, individual adults searching for prey on hemlock seedlings (infested or uninfested) were continuously video-recorded. Beetles located and began climbing the seedling stem in light significantly more than in dark, indicating that vision is an important sensory modality. Our primary finding was that searching behavior of L. nigrinus, as in most species, was related to food abundance. Beetles did not fly in the presence of high A. tsugae densities and flew when A. tsugae was absent, which agrees with observed aggregations of beetles on heavily infested trees in the field. At close range of prey, slow crawling and frequent turning suggest the use of non-visual cues such as olfaction and contact chemoreception. Based on the beetles' visual ability to locate tree stems and their climbing behavior, a bole trap may be an effective collection and monitoring tool.

  11. Contrasting roles for parvalbumin-expressing inhibitory neurons in two forms of adult visual cortical plasticity

    PubMed Central

    Kaplan, Eitan S; Cooke, Sam F; Komorowski, Robert W; Chubykin, Alexander A; Thomazeau, Aurore; Khibnik, Lena A; Gavornik, Jeffrey P; Bear, Mark F

    2016-01-01

    The roles played by cortical inhibitory neurons in experience-dependent plasticity are not well understood. Here we evaluate the participation of parvalbumin-expressing (PV+) GABAergic neurons in two forms of experience-dependent modification of primary visual cortex (V1) in adult mice: ocular dominance (OD) plasticity resulting from monocular deprivation and stimulus-selective response potentiation (SRP) resulting from enriched visual experience. These two forms of plasticity are triggered by different events but lead to a similar increase in visual cortical response. Both also require the NMDA class of glutamate receptor (NMDAR). However, we find that PV+ inhibitory neurons in V1 play a critical role in the expression of SRP and its behavioral correlate of familiarity recognition, but not in the expression of OD plasticity. Furthermore, NMDARs expressed within PV+ cells, reversibly inhibited by the psychotomimetic drug ketamine, play a critical role in SRP, but not in the induction or expression of adult OD plasticity. DOI: http://dx.doi.org/10.7554/eLife.11450.001 PMID:26943618

  12. The research on projective visual system of night vision goggles

    NASA Astrophysics Data System (ADS)

    Zhao, Shun-long

    2009-07-01

    Driven by the need for lightweight night vision goggles with good performance, we apply the projective lens into night vision goggles to act as visual system. A 40-deg FOV projection lens is provided. The useful diameter of the image intensifier is 16mm, and the Resolutions at Center and edge are both 60-lp/mm. The projection lens has a 28mm diameter and 20g weight. The maximum distortion of the system is less than 0.15%. The MTF maintained more than 0.6 at a 60-lp/mm resolution across the FOV. So the lens meets the requirements of the visual system. Besides, two types of projective visual system of night vision goggles are presented: the Direct-view projective visual system and the Seethrough projective visual system. And the See-through projective visual system enables us to observe the object with our eyes directly, without other action, when the environment becomes bright in a sudden. Finally we have reached a conclusion: The projective system has advantages over traditional eyepiece in night vision goggles. It is very useful to minish the volume, lighten the neck supports, and improve the imaging quality. It provides a new idea and concept for visual system design in night vision goggles.

  13. Normative shifts of cortical mechanisms of encoding contribute to adult age differences in visual-spatial working memory.

    PubMed

    Störmer, Viola S; Li, Shu-Chen; Heekeren, Hauke R; Lindenberger, Ulman

    2013-06-01

    The capacity of visual-spatial working memory (WM) declines from early to late adulthood. Recent attempts at identifying neural correlates of WM capacity decline have focused on the maintenance phase of WM. Here, we investigate neural mechanisms during the encoding phase as another potential mechanism contributing to adult age differences in WM capacity. We used electroencephalography to track neural activity during encoding and maintenance on a millisecond timescale in 35 younger and 35 older adults performing a visual-spatial WM task. As predicted, we observed pronounced age differences in ERP indicators of WM encoding: Younger adults showed attentional selection during item encoding (N2pc component), but this selection mechanism was greatly attenuated in older adults. Conversely, older adults showed more pronounced signs of early perceptual stimulus processing (N1 component) than younger adults. The amplitude modulation of the N1 component predicted WM capacity in older adults, whereas the attentional amplitude modulation of the N2pc component predicted WM capacity in younger adults. Our findings suggest that adult age differences in mechanisms of WM encoding contribute to adult age differences in limits of visual-spatial WM capacity.

  14. Larval vision contributes to gregarious settlement in barnacles: adult red fluorescence as a possible visual signal.

    PubMed

    Matsumura, Kiyotaka; Qian, Pei-Yuan

    2014-03-01

    Gregarious settlement, an essential behavior for many barnacle species that can only reproduce by mating with a nearby barnacle, has long been thought to rely on larval ability to recognize chemical signals from conspecifics during settlement. However, the cyprid, the settlement stage larva in barnacles, has one pair of compound eyes that appear only at the late nauplius VI and cyprid stages, but the function(s) of these eyes remains unknown. Here we show that cyprids of the intertidal barnacle Balanus (=Amphibalanus) amphitrite can locate adult barnacles even in the absence of chemical cues, and prefer to settle around them probably via larval sense of vision. We also show that the cyprids can discriminate color and preferred to settle on red surfaces. Moreover, we found that shells of adult B. amphitrite emit red auto-fluorescence and the adult extracts with the fluorescence as a visual signal attracted cyprid larvae to settle around it. We propose that the perception of specific visual signals can be involved in behavior of zooplankton including marine invertebrate larvae, and that barnacle auto-fluorescence may be a specific signal involved in gregarious larval settlement.

  15. Impaired visual expertise for print in French adults with dyslexia as shown by N170 tuning.

    PubMed

    Mahé, Gwendoline; Bonnefond, Anne; Gavens, Nathalie; Dufour, André; Doignon-Camus, Nadège

    2012-12-01

    Efficient reading relies on expertise in the visual word form area, with abnormalities in the functional specialization of this area observed in individuals with developmental dyslexia. We have investigated event related potentials in print tuning in adults with dyslexia, based on their N170 response at 135-255 ms. Control and dyslexic adults performed a lexical decision task with symbol strings and four sets of word-like stimuli (consonant strings, pseudowords, low frequency words and high frequency words). N170 tuning was observed in the control group, with larger left occipito-temporal negativities for word-like stimuli than for symbol strings. In contrast, N170 specialization was lacking in dyslexics, suggesting no visual expertise for print. Moreover, behavioral data indicated that adults with dyslexia had longer latencies and more errors for pseudowords than for other stimuli, suggesting a persistent phonological deficit in these individuals. These findings suggest that altered decoding abilities may disrupt perceptual expertise for print. The results are discussed in the context of the phonological mapping deficit theory.

  16. Visual search and contextual cueing: differential effects in 10-year-old children and adults.

    PubMed

    Couperus, Jane W; Hunt, Ruskin H; Nelson, Charles A; Thomas, Kathleen M

    2011-02-01

    The development of contextual cueing specifically in relation to attention was examined in two experiments. Adult and 10-year-old participants completed a context cueing visual search task (Jiang & Chun, The Quarterly Journal of Experimental Psychology, 54A(4), 1105-1124, 2001) containing stimuli presented in an attended (e.g., red) and unattended (e.g., green) color. When the spatial configuration of stimuli in the attended and unattended color was invariant and consistently paired with the target location, adult reaction times improved, demonstrating learning. Learning also occurred if only the attended stimuli's configuration remained fixed. In contrast, while 10 year olds, like adults, showed incrementally slower reaction times as the number of attended stimuli increased, they did not show learning in the standard paradigm. However, they did show learning when the ratio of attended to unattended stimuli was high, irrespective of the total number of attended stimuli. Findings suggest children show efficient attentional guidance by color in visual search but differences in contextual cueing.

  17. What Visual Information Do Children and Adults Consider while Switching between Tasks? Eye-Tracking Investigation of Cognitive Flexibility Development

    ERIC Educational Resources Information Center

    Chevalier, Nicolas; Blaye, Agnes; Dufau, Stephane; Lucenet, Joanna

    2010-01-01

    This study investigated the visual information that children and adults consider while switching or maintaining object-matching rules. Eye movements of 5- and 6-year-old children and adults were collected with two versions of the Advanced Dimensional Change Card Sort, which requires switching between shape- and color-matching rules. In addition to…

  18. The Effect of Karate Practice on Self-Esteem in Young Adults with Visual Impairment: A Case Study

    ERIC Educational Resources Information Center

    Qasim, Samir; Ravenscroft, John; Sproule, John

    2014-01-01

    Previous research has not examined the potential relationship between physical activity interventions and psychological domains of young adults with visual impairment (VI). This study aimed to investigate whether karate practice improves the self-esteem of young adults with VI. A secondary aim of this study was to explore the exercise and…

  19. Self-Control and Impulsiveness in Nondieting Adult Human Females: Effects of Visual Food Cues and Food Deprivation

    ERIC Educational Resources Information Center

    Forzano, Lori-Ann B.; Chelonis, John J.; Casey, Caitlin; Forward, Marion; Stachowiak, Jacqueline A.; Wood, Jennifer

    2010-01-01

    Self-control can be defined as the choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer, and impulsiveness as the opposite. Previous research suggests that exposure to visual food cues affects adult humans' self-control. Previous research also suggests that food deprivation decreases adult humans' self-control. The…

  20. An annotation system for 3D fluid flow visualization

    NASA Technical Reports Server (NTRS)

    Loughlin, Maria M.; Hughes, John F.

    1995-01-01

    Annotation is a key activity of data analysis. However, current systems for data analysis focus almost exclusively on visualization. We propose a system which integrates annotations into a visualization system. Annotations are embedded in 3D data space, using the Post-it metaphor. This embedding allows contextual-based information storage and retrieval, and facilitates information sharing in collaborative environments. We provide a traditional database filter and a Magic Lens filter to create specialized views of the data. The system has been customized for fluid flow applications, with features which allow users to store parameters of visualization tools and sketch 3D volumes.

  1. History of visual systems in the Systems Engineering Simulator

    NASA Technical Reports Server (NTRS)

    Christianson, David C.

    1989-01-01

    The Systems Engineering Simulator (SES) houses a variety of real-time computer generated visual systems. The earliest machine dates from the mid-1960's and is one of the first real-time graphics systems in the world. The latest acquisition is the state-of-the-art Evans and Sutherland CT6. Between the span of time from the mid-1960's to the late 1980's, tremendous strides have been made in the real-time graphics world. These strides include advances in both software and hardware engineering. The purpose is to explore the history of the development of these real-time computer generated image systems from the first machine to the present. Hardware advances as well as software algorithm changes are presented. This history is not only quite interesting but also provides us with a perspective with which we can look backward and forward.

  2. Attuning one's steps to visual targets reduces comfortable walking speed in both young and older adults.

    PubMed

    Peper, C Lieke E; de Dreu, Miek J; Roerdink, Melvyn

    2015-03-01

    Comfortable walking speed (CWS) is indicative of clinically relevant factors in the elderly, such as fall risk and mortality. Standard CWS tests involve walking on a straight, unobstructed surface, while in reality surfaces are uneven and cluttered and so walkers rely on visually guided adaptations to avoid trips or slips. Hence, the predictive value of CWS may be expected to increase when assessed for walking in more realistic (visually guided) conditions. We examined CWS in young (n=18) and older (n=18) adults for both overground and treadmill walking. Overground CWS was assessed using the 10-meter walk test with and without visual stepping targets. For treadmill walking, four conditions were examined: (i) uncued walking, and (ii-iv) cued walking with visual stepping targets where the inter-stepping target distance varied by 0%, 20%, or 40%. Pre-experimental measures were taken so that the average inter-stepping target distance could be adjusted for each belt speed based on each participant's self-selected gait characteristics. Results showed that CWS was significantly slower when stepping targets were present in both overground (p<.001) and treadmill walking (p<.001). Thus, attuning steps to visual targets significantly affected CWS, even when the patterning of these targets matched the participant's own gait pattern (viz. 0%-treadmill-walking condition). Results from the treadmill-walking task showed that the amount of variation in inter-stepping target distance did not differentially affect CWS. Our results suggest that it may be worthwhile in clinical assessments to not only determine walking speed using standard conditions but also in situations that require visually guided stepping.

  3. mRNAs coding for neurotransmitter receptors and voltage-gated sodium channels in the adult rabbit visual cortex after monocular deafferentiation

    PubMed Central

    Nguyen, Quoc-Thang; Matute, Carlos; Miledi, Ricardo

    1998-01-01

    It has been postulated that, in the adult visual cortex, visual inputs modulate levels of mRNAs coding for neurotransmitter receptors in an activity-dependent manner. To investigate this possibility, we performed a monocular enucleation in adult rabbits and, 15 days later, collected their left and right visual cortices. Levels of mRNAs coding for voltage-activated sodium channels, and for receptors for kainate/α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), N-methyl-d-aspartate (NMDA), γ-aminobutyric acid (GABA), and glycine were semiquantitatively estimated in the visual cortices ipsilateral and contralateral to the lesion by the Xenopus oocyte/voltage-clamp expression system. This technique also allowed us to study some of the pharmacological and physiological properties of the channels and receptors expressed in the oocytes. In cells injected with mRNA from left or right cortices of monocularly enucleated and control animals, the amplitudes of currents elicited by kainate or AMPA, which reflect the abundance of mRNAs coding for kainate and AMPA receptors, were similar. There was no difference in the sensitivity to kainate and in the voltage dependence of the kainate response. Responses mediated by NMDA, GABA, and glycine were unaffected by monocular enucleation. Sodium channel peak currents, activation, steady-state inactivation, and sensitivity to tetrodotoxin also remained unchanged after the enucleation. Our data show that mRNAs for major neurotransmitter receptors and ion channels in the adult rabbit visual cortex are not obviously modified by monocular deafferentiation. Thus, our results do not support the idea of a widespread dynamic modulation of mRNAs coding for receptors and ion channels by visual activity in the rabbit visual system. PMID:9501250

  4. Falcon: A Temporal Visual Analysis System

    SciTech Connect

    Steed, Chad A.

    2016-09-05

    Flexible visible exploration of long, high-resolution time series from multiple sensor streams is a challenge in several domains. Falcon is a visual analytics approach that helps researchers acquire a deep understanding of patterns in log and imagery data. Falcon allows users to interactively explore large, time-oriented data sets from multiple linked perspectives. Falcon provides overviews, detailed views, and unique segmented time series visualizations with multiple levels of detail. These capabilities are applicable to the analysis of any quantitative time series.

  5. Framework for an Information Visualization System

    SciTech Connect

    Risch, John; Dowson, Scott; Hatley, Wes

    2006-08-11

    The Program is a suite of Windows-based software applications and services for ingesting, storing, and analyzing large quantities of disparate inforamtion. The software supports the ingestion and storage of any information that can be represented in eXtensible Markup Language (XML) format. Stored information can be subsequently retrieved via search operations, then "visualized" in multiple ways using a client application that supports a variety of analytical functions. Visualization capabilities include tools for depicting a variety of relationships that may be present in the information, including geospatial, temporal, topical, categorical, and network relationships.

  6. Trail Making Test performance contributes to subjective judgment of visual efficiency in older adults

    PubMed Central

    Loughman, James; Savva, George M.; Kenny, RoseAnne

    2015-01-01

    Introduction. The determinant factors that influence self-reported quality of vision have yet to be fully elucidated. This study evaluated a range of contextual information, established psychophysical tests, and in particular, a series of cognitive tests as potentially novel determinant factors. Materials & Methods. Community dwelling adults (aged 50+) recruited to Wave 1 of The Irish Longitudinal Study on Ageing, excluding those registered blind, participated in this study (N = 5,021). Self-reports of vision were analysed in relation to visual acuity and contrast sensitivity, ocular pathology, visual (Choice Response Time task; Trail Making Test) and global cognition. Contextual factors such as having visited an optometrist and wearing glasses were also considered. Ordinal logistic regression was used to determine univariate and multivariate associations. Results and Discussion. Poor Trail Making Test performance (Odds ratio, OR = 1.36), visual acuity (OR = 1.72) and ocular pathology (OR = 2.25) were determinant factors for poor versus excellent vision in self-reports. Education, wealth, age, depressive symptoms and general cognitive fitness also contributed to determining self-reported vision. Conclusions. Trail Making Test contribution to self-reports may capture higher level visual processing and should be considered when using self-reports to assess vision and its role in cognitive and functional health. PMID:26664798

  7. Methylphenidate (MPH) promotes visual cortical activation in healthy adults in a cued visuomotor task.

    PubMed

    Hodzhev, Yordan; Yordanova, Juliana; Diruf, Martin; Kratz, Oliver; Moll, Gunter H; Kolev, Vasil; Heinrich, Hartmut

    2012-11-01

    Seeking for the mechanisms by which methylphenidate (MPH) improves behavior has demonstrated that MPH modulates excitability in the primary motor cortex. However, little is known about the influence of MPH on top-down controlled mechanisms in the sensory domain. The present study explored the effects of MPH on the activation of visual cortices in healthy adults who performed a cued visuo-motor task in a double-blind placebo-controlled crossover design. Two distinct measures, posterior alpha power and occipital slow cortical potentials (SCPs), were used to reflect raise in excitability and attention-based activation of visual cortical areas. According to the results, performance parameters (reaction time, response variance and error rate) were not affected by MPH. At the neurophysiologic level reflected by reduced alpha power, MPH increased the overall excitability of the occipital cortex, but not the parietal cortex. Before the cued response, MPH reduced alpha power and increased SCPs only before right hand responses, mostly at the right occipital location. It can be concluded that in visuo-motor tasks, MPH has the potency of adjusting the background excitation/inhibition balance of visual areas. Additionally, MPH may raise the attention controlled activation of visual cortical regions, especially during increased response control.

  8. The two-visual-systems hypothesis and the perspectival features of visual experience.

    PubMed

    Foley, Robert T; Whitwell, Robert L; Goodale, Melvyn A

    2015-09-01

    Some critics of the two-visual-systems hypothesis (TVSH) argue that it is incompatible with the fundamentally egocentric nature of visual experience (what we call the 'perspectival account'). The TVSH proposes that the ventral stream, which delivers up our visual experience of the world, works in an allocentric frame of reference, whereas the dorsal stream, which mediates the visual control of action, uses egocentric frames of reference. Given that the TVSH is also committed to the claim that dorsal-stream processing does not contribute to the contents of visual experience, it has been argued that the TVSH cannot account for the egocentric features of our visual experience. This argument, however, rests on a misunderstanding about how the operations mediating action and the operations mediating perception are specified in the TVSH. In this article, we emphasize the importance of the 'outputs' of the two-systems to the specification of their respective operations. We argue that once this point is appreciated, it becomes evident that the TVSH is entirely compatible with a perspectival account of visual experience.

  9. Brain activation during visual working memory correlates with behavioral mobility performance in older adults.

    PubMed

    Kawagoe, Toshikazu; Suzuki, Maki; Nishiguchi, Shu; Abe, Nobuhito; Otsuka, Yuki; Nakai, Ryusuke; Yamada, Minoru; Yoshikawa, Sakiko; Sekiyama, Kaoru

    2015-01-01

    Functional mobility and cognitive function often decline with age. We previously found that functional mobility as measured by the Timed Up and Go Test (TUG) was associated with cognitive performance for visually-encoded (i.e., for location and face) working memory (WM) in older adults. This suggests a common neural basis between TUG and visual WM. To elucidate this relationship further, the present study aimed to examine the neural basis for the WM-mobility association. In accordance with the well-known neural compensation model in aging, we hypothesized that "attentional" brain activation for easy WM would increase in participants with lower mobility. The data from 32 healthy older adults were analyzed, including brain activation during easy WM tasks via functional Magnetic Resonance Imaging (fMRI) and mobility performance via both TUG and a simple walking test. WM performance was significantly correlated with TUG but not with simple walking. Some prefrontal brain activations during WM were negatively correlated with TUG performance, while positive correlations were found in subcortical structures including the thalamus, putamen and cerebellum. Moreover, activation of the subcortical regions was significantly correlated with WM performance, with less activation for lower WM performers. These results indicate that older adults with lower mobility used more cortical (frontal) and fewer subcortical resources for easy WM tasks. To date, the frontal compensation has been proposed separately in the motor and cognitive domains, which have been assumed to compensate for dysfunction of the other brain areas; however, such dysfunction was less clear in previous studies. The present study observed such dysfunction as degraded activation associated with lower performance, which was found in the subcortical regions. We conclude that a common dysfunction-compensation activation pattern is likely the neural basis for the association between visual WM and functional mobility.

  10. Brain activation during visual working memory correlates with behavioral mobility performance in older adults

    PubMed Central

    Kawagoe, Toshikazu; Suzuki, Maki; Nishiguchi, Shu; Abe, Nobuhito; Otsuka, Yuki; Nakai, Ryusuke; Yamada, Minoru; Yoshikawa, Sakiko; Sekiyama, Kaoru

    2015-01-01

    Functional mobility and cognitive function often decline with age. We previously found that functional mobility as measured by the Timed Up and Go Test (TUG) was associated with cognitive performance for visually-encoded (i.e., for location and face) working memory (WM) in older adults. This suggests a common neural basis between TUG and visual WM. To elucidate this relationship further, the present study aimed to examine the neural basis for the WM-mobility association. In accordance with the well-known neural compensation model in aging, we hypothesized that “attentional” brain activation for easy WM would increase in participants with lower mobility. The data from 32 healthy older adults were analyzed, including brain activation during easy WM tasks via functional Magnetic Resonance Imaging (fMRI) and mobility performance via both TUG and a simple walking test. WM performance was significantly correlated with TUG but not with simple walking. Some prefrontal brain activations during WM were negatively correlated with TUG performance, while positive correlations were found in subcortical structures including the thalamus, putamen and cerebellum. Moreover, activation of the subcortical regions was significantly correlated with WM performance, with less activation for lower WM performers. These results indicate that older adults with lower mobility used more cortical (frontal) and fewer subcortical resources for easy WM tasks. To date, the frontal compensation has been proposed separately in the motor and cognitive domains, which have been assumed to compensate for dysfunction of the other brain areas; however, such dysfunction was less clear in previous studies. The present study observed such dysfunction as degraded activation associated with lower performance, which was found in the subcortical regions. We conclude that a common dysfunction—compensation activation pattern is likely the neural basis for the association between visual WM and functional

  11. Visualizing Terrestrial and Aquatic Systems in 3-D

    EPA Science Inventory

    The environmental modeling community has a long-standing need for affordable, easy-to-use tools that support 3-D visualization of complex spatial and temporal model output. The Visualization of Terrestrial and Aquatic Systems project (VISTAS) aims to help scientists produce effe...

  12. A phrase-driven grammar system for interactive data visualization

    NASA Astrophysics Data System (ADS)

    Lee, Sang Yun; Neumann, Ulrich

    2008-01-01

    A Phrase-Driven Grammar System (PDGS) is a novel GUI for facilitating the visualization of data. The PDGS integrates data source applications and external visualization tools into its framework and functions as a middle-layer application to coordinate their operations. It allows users to formulate data query and visualization descriptions by selecting graphical icons in a menu or on a map. To specify data query and visualization intuitively and efficiently, we designed Graphical User Interface and a natural-language-like grammar, Phrase-Driven Grammar (PDG). The formulation of PDG data query and visualization descriptions is a constrained natural-language phrase building process. PDG phrases produce graphical visualizations of the data query, allowing users to interactively explore meaningful data relationships, trends, and exceptions.

  13. A Behavioral Treatment for Traumatic Brain Injury-Associated Visual Dysfunction Based on Adult Cortical Plasticity

    DTIC Science & Technology

    2013-10-01

    balance between neuronal excitation or inhibition (He, Hodos & Quinlan, 2006,  Maya  Vetencourt, Sale, Viegi, Baroncelli, De Pasquale, O’Leary, Castren...adult visual cortex. J Neurosci, 26 (11), 2951‐2955.  Maya  Vetencourt, J.F., Sale, A., Viegi, A., Baroncelli, L., De Pasquale, R., O’Leary, O.F

  14. The oral health status of adults with a visual impairment, their dental care and oral health information needs.

    PubMed

    Watson, E K; Moles, D R; Kumar, N; Porter, S R

    2010-04-24

    AIM There is little information available concerning the impact of visual impairment upon oral health. The present study sought to identify the oral health and experiences of adults with a visual impairment together with the nature, source and access to oral health information. In addition the study evaluated the oral health status of a group of individuals with a visual impairment with respect to oral health markers, treatment choice and attendance patterns in comparison to a reference group from the general population in the United Kingdom. METHOD One hundred adults with a visual impairment were examined and completed a questionnaire concerning their experience of oral health care and available information sources. The information collected was directly compared with data from the Adult Dental Health Survey 1998 for the south region of England. RESULTS The present group of individuals with a visual impairment had better oral hygiene practices, and similar levels of oral hygiene and hard tissue disease to those of a comparable group of the Adult Dental Health Survey 1998 (ADHS 1998). However 24% of those with a visual impairment were not registered with a dentist and 26% of the patients wished for appropriate information concerning oral health care. CONCLUSIONS There is a need to develop oral health promotion that ensures patients with a visual impairment have appropriate information regarding oral health care and its provision.

  15. Video game training to improve selective visual attention in older adults

    PubMed Central

    Belchior, Patrícia; Marsiske, Michael; Sisco, Shannon M.; Yam, Anna; Bavelier, Daphne; Ball, Karlene; Mann, William C.

    2013-01-01

    The current study investigated the effect of video game training on older adult’s useful field of view performance (the UFOV® test). Fifty-eight older adult participants were randomized to receive practice with the target action game (Medal of Honor), a placebo control arcade game (Tetris), a clinically validated UFOV training program, or into a no contact control group. Examining pretest–posttest change in selective visual attention, the UFOV improved significantly more than the game groups; all three intervention groups improved significantly more than no-contact controls. There was a lack of difference between the two game conditions, differing from findings with younger adults. Discussion considers whether games posing less challenge might still be effective interventions for elders, and whether optimal training dosages should be higher. PMID:24003265

  16. Lightening the load: perceptual load impairs visual detection in typical adults but not in autism.

    PubMed

    Remington, Anna M; Swettenham, John G; Lavie, Nilli

    2012-05-01

    Autism spectrum disorder (ASD) research portrays a mixed picture of attentional abilities with demonstrations of enhancements (e.g., superior visual search) and deficits (e.g., higher distractibility). Here we test a potential resolution derived from the Load Theory of Attention (e.g., Lavie, 2005). In Load Theory, distractor processing depends on the perceptual load of the task and as such can only be eliminated under high load that engages full capacity. We hypothesize that ASD involves enhanced perceptual capacity, leading to the superior performance and increased distractor processing previously reported. Using a signal-detection paradigm, we test this directly and demonstrate that, under higher levels of load, perceptual sensitivity was reduced in typical adults but not in adults with ASD. These findings confirm our hypothesis and offer a promising solution to the previous discrepancies by suggesting that increased distractor processing in ASD results not from a filtering deficit but from enhanced perceptual capacity.

  17. Visualization of an entangled channel spin-1 system

    SciTech Connect

    Sirsi, Swarnamala; Adiga, Veena

    2010-08-15

    Covariance matrix formalism gives powerful entanglement criteria for continuous as well as finite dimensional systems. We use this formalism to study a mixed channel spin-1 system which is well known in nuclear reactions. A spin-j state can be visualized as being made up of 2j spinors which are represented by a constellation of 2j points on a Bloch sphere using Majorana construction. We extend this formalism to visualize an entangled mixed spin-1 system.

  18. Audio-Visual Perception of Gender by Infants Emerges Earlier for Adult-Directed Speech

    PubMed Central

    Richoz, Anne-Raphaëlle; Quinn, Paul C.; Hillairet de Boisferon, Anne; Berger, Carole; Loevenbruck, Hélène; Lewkowicz, David J.; Lee, Kang; Dole, Marjorie; Caldara, Roberto; Pascalis, Olivier

    2017-01-01

    Early multisensory perceptual experiences shape the abilities of infants to perform socially-relevant visual categorization, such as the extraction of gender, age, and emotion from faces. Here, we investigated whether multisensory perception of gender is influenced by infant-directed (IDS) or adult-directed (ADS) speech. Six-, 9-, and 12-month-old infants saw side-by-side silent video-clips of talking faces (a male and a female) and heard either a soundtrack of a female or a male voice telling a story in IDS or ADS. Infants participated in only one condition, either IDS or ADS. Consistent with earlier work, infants displayed advantages in matching female relative to male faces and voices. Moreover, the new finding that emerged in the current study was that extraction of gender from face and voice was stronger at 6 months with ADS than with IDS, whereas at 9 and 12 months, matching did not differ for IDS versus ADS. The results indicate that the ability to perceive gender in audiovisual speech is influenced by speech manner. Our data suggest that infants may extract multisensory gender information developmentally earlier when looking at adults engaged in conversation with other adults (i.e., ADS) than when adults are directly talking to them (i.e., IDS). Overall, our findings imply that the circumstances of social interaction may shape early multisensory abilities to perceive gender. PMID:28060872

  19. An adult-like pattern of ocular dominance columns in striate cortex of newborn monkeys prior to visual experience.

    PubMed

    Horton, J C; Hocking, D R

    1996-03-01

    In macaque monkeys, the geniculocortical afferents serving each eye segregate in layer IVc of striate cortex during early life into a pattern of alternating inputs called ocular dominance columns. It has been disputed whether visual experience is necessary for the formation of ocular dominance columns. To settle this issue, fetal monkeys were delivered prematurely by Caesarean section at embryonic day 157 (E157), 8 d before the end of normal gestation. To avoid light exposure, the Caesarean section and all subsequent feedings and procedures were done in absolute darkness, using infrared night-vision goggles. Tritiated proline was injected into the right eye 1 d after delivery (E158). One week later at postnatal age 0 (P0), the equivalent of a full-term pregnancy (E165/P0), alternate sections of unfolded and flattened visual cortex were prepared for autoradiography or cytochrome oxidase (CO). All three newborns studied at E165/P0 had well segregated ocular dominance columns organized into the characteristic mosaic present in adults. In the upper layers, a mature pattern of CO patches (also known as blobs or puffs) was visible, aligned with the ocular dominance columns in layer IVc. Every other row of patches in layers II, III was labeled by [3H]proline. In V2, a distinct system of alternating thick-pale-thin-pale CO stripes was present. These findings indicate that stimulation of the retina by light is not necessary for the development of columnar systems in the visual cortex. Ocular dominance columns, patches, and V2 stripes all are well formed before visual experience. Even the thalamic input to the patches in the upper layers of striate cortex is segregated by eye in newborns.

  20. Vision and agility training in community dwelling older adults: incorporating visual training into programs for fall prevention.

    PubMed

    Reed-Jones, Rebecca J; Dorgo, Sandor; Hitchings, Maija K; Bader, Julia O

    2012-04-01

    This study aimed to examine the effect of visual training on obstacle course performance of independent community dwelling older adults. Agility is the ability to rapidly alter ongoing motor patterns, an important aspect of mobility which is required in obstacle avoidance. However, visual information is also a critical factor in successful obstacle avoidance. We compared obstacle course performance of a group that trained in visually driven body movements and agility drills, to a group that trained only in agility drills. We also included a control group that followed the American College of Sports Medicine exercise recommendations for older adults. Significant gains in fitness, mobility and power were observed across all training groups. Obstacle course performance results revealed that visual training had the greatest improvement on obstacle course performance (22%) following a 12 week training program. These results suggest that visual training may be an important consideration for fall prevention programs.

  1. Visual Analytics for Complex Engineering Systems: Hybrid Visual Steering of Simulation Ensembles.

    PubMed

    Matković, Krešimir; Gračanin, Denis; Splechtna, Rainer; Jelović, Mario; Stehno, Benedikt; Hauser, Helwig; Purgathofer, Werner

    2014-12-01

    In this paper we propose a novel approach to hybrid visual steering of simulation ensembles. A simulation ensemble is a collection of simulation runs of the same simulation model using different sets of control parameters. Complex engineering systems have very large parameter spaces so a naïve sampling can result in prohibitively large simulation ensembles. Interactive steering of simulation ensembles provides the means to select relevant points in a multi-dimensional parameter space (design of experiment). Interactive steering efficiently reduces the number of simulation runs needed by coupling simulation and visualization and allowing a user to request new simulations on the fly. As system complexity grows, a pure interactive solution is not always sufficient. The new approach of hybrid steering combines interactive visual steering with automatic optimization. Hybrid steering allows a domain expert to interactively (in a visualization) select data points in an iterative manner, approximate the values in a continuous region of the simulation space (by regression) and automatically find the "best" points in this continuous region based on the specified constraints and objectives (by optimization). We argue that with the full spectrum of optimization options, the steering process can be improved substantially. We describe an integrated system consisting of a simulation, a visualization, and an optimization component. We also describe typical tasks and propose an interactive analysis workflow for complex engineering systems. We demonstrate our approach on a case study from automotive industry, the optimization of a hydraulic circuit in a high pressure common rail Diesel injection system.

  2. Eye movement-invariant representations in the human visual system

    PubMed Central

    Nishimoto, Shinji; Huth, Alexander G.; Bilenko, Natalia Y.; Gallant, Jack L.

    2017-01-01

    During natural vision, humans make frequent eye movements but perceive a stable visual world. It is therefore likely that the human visual system contains representations of the visual world that are invariant to eye movements. Here we present an experiment designed to identify visual areas that might contain eye-movement-invariant representations. We used functional MRI to record brain activity from four human subjects who watched natural movies. In one condition subjects were required to fixate steadily, and in the other they were allowed to freely make voluntary eye movements. The movies used in each condition were identical. We reasoned that the brain activity recorded in a visual area that is invariant to eye movement should be similar under fixation and free viewing conditions. In contrast, activity in a visual area that is sensitive to eye movement should differ between fixation and free viewing. We therefore measured the similarity of brain activity across repeated presentations of the same movie within the fixation condition, and separately between the fixation and free viewing conditions. The ratio of these measures was used to determine which brain areas are most likely to contain eye movement-invariant representations. We found that voxels located in early visual areas are strongly affected by eye movements, while voxels in ventral temporal areas are only weakly affected by eye movements. These results suggest that the ventral temporal visual areas contain a stable representation of the visual world that is invariant to eye movements made during natural vision. PMID:28114479

  3. Eye movement-invariant representations in the human visual system.

    PubMed

    Nishimoto, Shinji; Huth, Alexander G; Bilenko, Natalia Y; Gallant, Jack L

    2017-01-01

    During natural vision, humans make frequent eye movements but perceive a stable visual world. It is therefore likely that the human visual system contains representations of the visual world that are invariant to eye movements. Here we present an experiment designed to identify visual areas that might contain eye-movement-invariant representations. We used functional MRI to record brain activity from four human subjects who watched natural movies. In one condition subjects were required to fixate steadily, and in the other they were allowed to freely make voluntary eye movements. The movies used in each condition were identical. We reasoned that the brain activity recorded in a visual area that is invariant to eye movement should be similar under fixation and free viewing conditions. In contrast, activity in a visual area that is sensitive to eye movement should differ between fixation and free viewing. We therefore measured the similarity of brain activity across repeated presentations of the same movie within the fixation condition, and separately between the fixation and free viewing conditions. The ratio of these measures was used to determine which brain areas are most likely to contain eye movement-invariant representations. We found that voxels located in early visual areas are strongly affected by eye movements, while voxels in ventral temporal areas are only weakly affected by eye movements. These results suggest that the ventral temporal visual areas contain a stable representation of the visual world that is invariant to eye movements made during natural vision.

  4. Children's and Adults' Memory for Emotional Pictures: Examining Age-Related Patterns Using the Developmental Affective Photo System

    ERIC Educational Resources Information Center

    Cordon, Ingrid M.; Melinder, Annika M. D.; Goodman, Gail S.; Edelstein, Robin S.

    2013-01-01

    Two studies were conducted to examine theoretical questions about children's and adults' memory for emotional visual stimuli. In Study 1, 7- to 9-year-olds and adults (N = 172) participated in the initial creation of the Developmental Affective Photo System (DAPS). Ratings of emotional valence, arousal, and complexity were obtained. In Study 2,…

  5. Conceptual design study for a teleoperator visual system, phase 1

    NASA Technical Reports Server (NTRS)

    Adams, D.; Grant, C.; Johnson, C.; Meirick, R.; Polhemus, C.; Ray, A.; Rittenhouse, D.; Skidmore, R.

    1972-01-01

    Results are reported for work performed during the first phase of the conceptual design study for a teleoperator visual system. This phase consists of four tasks: General requirements, concept development, subsystem requirements and analysis, and concept evaluation.

  6. Anatomy, development, and physiology of the visual system.

    PubMed

    Edward, Deepak P; Kaufman, Lawrence M

    2003-02-01

    This article serves to familiarize the reader with the normal anatomy, embryology, and physiology of the visual system. Other articles in this issue introduce examination techniques and the pathology of the eyes of pediatric patients.

  7. Stepped care for depression and anxiety in visually impaired older adults: multicentre randomised controlled trial

    PubMed Central

    van Rens, Ger H M B; Comijs, Hannie C; Margrain, Tom H; Gallindo-Garre, Francisca; Twisk, Jos W R; van Nispen, Ruth M A

    2015-01-01

    Study question Is stepped care compared with usual care effective in preventing the onset of major depressive, dysthymic, and anxiety disorders in older people with visual impairment (caused mainly by age related eye disease) and subthreshold depression and/or anxiety? Methods 265 people aged ≥50 were randomly assigned to a stepped care programme plus usual care (n=131) or usual care only (n=134). Supervised occupational therapists, social workers, and psychologists from low vision rehabilitation organisations delivered the stepped care programme, which comprised watchful waiting, guided self help based on cognitive behavioural therapy, problem solving treatment, and referral to a general practitioner. The primary outcome was the 24 month cumulative incidence (seven measurements) of major depressive dysthymic and/or anxiety disorders (panic disorder, agoraphobia, social phobia, and generalised anxiety disorder). Secondary outcomes were change in symptoms of depression and anxiety, vision related quality of life, health related quality of life, and adaptation to vision loss over time up to 24 months’ follow-up. Study answer and limitations 62 participants (46%) in the usual care group and 38 participants (29%) from the stepped care group developed a disorder. The intervention was associated with a significantly reduced incidence (relative risk 0.63, 95% confidence interval 0.45 to 0.87; P=0.01), even if time to the event was taken into account (adjusted hazard ratio 0.57, 0.35 to 0.93; P=0.02). The number needed to treat was 5.8 (3.5 to 17.3). The dropout rate was fairly high (34.3%), but rates were not significantly different for the two groups, indicating that the intervention was as acceptable as usual care. Participants who volunteered and were selected for this study might not be representative of visually impaired older adults in general (responders were significantly younger than non-responders), thereby reducing the generalisability of the outcomes. What

  8. Visually Coupled Systems (VCS): The Virtual Panoramic Display (VPD) System

    NASA Technical Reports Server (NTRS)

    Kocian, Dean F.

    1992-01-01

    The development and impact is described of new visually coupled system (VCS) equipment designed to support engineering and human factors research in the military aircraft cockpit environment. VCS represents an advanced man-machine interface (MMI). Its potential to improve aircrew situational awareness seems enormous, but its superiority over the conventional cockpit MMI has not been established in a conclusive and rigorous fashion. What has been missing is a 'systems' approach to technology advancement that is comprehensive enough to produce conclusive results concerning the operational viability of the VCS concept and verify any risk factors that might be involved with its general use in the cockpit. The advanced VCS configuration described here, was ruggedized for use in military aircraft environments and was dubbed the Virtual Panoramic Display (VPD). It was designed to answer the VCS portion of the systems problem, and is implemented as a modular system whose performance can be tailored to specific application requirements. The overall system concept and the design of the two most important electronic subsystems that support the helmet mounted parts, a new militarized version of the magnetic helmet mounted sight and correspondingly similar helmet display electronics, are discussed in detail. Significant emphasis is given to illustrating how particular design features in the hardware improve overall system performance and support research activities.

  9. Description and performance of the Langley visual landing display system

    NASA Technical Reports Server (NTRS)

    Rollins, J. D.

    1978-01-01

    A television/model board system is described which provides a means of generating a six-degree-of-freedom visual out-the-window scene for the pilot of a simulated aircraft. The hardware and its performance of capability for meeting the visual requirements for a wide range of simulation studies are detailed. Also included is a description of the computer software required for the system. An example of software implementation in a real-time computer program is provided.

  10. Dopaminergic and cholinergic modulations of visual-spatial attention and working memory: insights from molecular genetic research and implications for adult cognitive development.

    PubMed

    Störmer, Viola S; Passow, Susanne; Biesenack, Julia; Li, Shu-Chen

    2012-05-01

    Attention and working memory are fundamental for selecting and maintaining behaviorally relevant information. Not only do both processes closely intertwine at the cognitive level, but they implicate similar functional brain circuitries, namely the frontoparietal and the frontostriatal networks, which are innervated by cholinergic and dopaminergic pathways. Here we review the literature on cholinergic and dopaminergic modulations of visual-spatial attention and visual working memory processes to gain insights on aging-related changes in these processes. Some extant findings have suggested that the cholinergic system plays a role in the orienting of attention to enable the detection and discrimination of visual information, whereas the dopaminergic system has mainly been associated with working memory processes such as updating and stabilizing representations. However, since visual-spatial attention and working memory processes are not fully dissociable, there is also evidence of interacting cholinergic and dopaminergic modulations of both processes. We further review gene-cognition association studies that have shown that individual differences in visual-spatial attention and visual working memory are associated with acetylcholine- and dopamine-relevant genes. The efficiency of these 2 transmitter systems declines substantially during healthy aging. These declines, in part, contribute to age-related deficits in attention and working memory functions. We report novel data showing an effect of dopamine COMT gene on spatial updating processes in older but not in younger adults, indicating potential magnification of genetic effects in old age.

  11. EEG alpha rhythms and transient chromatic and achromatic pattern visual evoked potentials in children and adults.

    PubMed

    Boon, Mei Ying; Chan, Kar Ying; Chiang, Jaclyn; Milston, Rebecca; Suttle, Catherine

    2011-04-01

    Transient chromatic pattern visual evoked potentials (VEPs) have been found to be less repeatable in morphology in children than in adults at low to moderate chromatic contrasts. The purpose of this study is to investigate whether low repeatability of VEP components can be associated with high alpha power, in a comparison of alpha activity in children and adults. Transient chromatic contrast and achromatic resolution VEPs were recorded in children (n = 14, mean 9.6 years) and adults (n = 12, mean 21.8 years) with normal vision and assessed for repeatability. Isoluminant chromatic (magenta-cyan) and luminance-modulated achromatic grating stimuli were presented at and above psychophysical threshold levels, in pattern onset-offset at 2 Hz temporal frequency. EEGs (eyes closed and open) were recorded as single sweeps (1 s long) over three 30 s periods while facing a uniform computer display. An index of VEP detectability by observation was developed based on VEP component repeatability. The index was examined for correlations with alpha-wave parameters. Alpha power was calculated as the sum of the powers of 8-13 Hz frequencies of the EEG sweeps (using the discrete Fourier transform). Alpha power variability was calculated using the standard deviation of the powers of each sweep in a 30 s time period. The children had significantly higher alpha powers than the adults for both the eyes-open and eyes-closed conditions. Alpha power variability was significantly higher for the eyes-open condition only. There was no relationship between alpha power parameters and index of VEP detectability by observation for both the chromatic and achromatic grating stimuli. Poor repeatability of transient pattern VEPs is not associated with high alpha power or its variability in EEG measurements in older children or young adults at Oz.

  12. Adults with dyslexia show deficits on spatial frequency doubling and visual attention tasks.

    PubMed

    Buchholz, Judy; McKone, Elinor

    2004-02-01

    We examine the visual processing of high-functioning adults with developmental dyslexia (mean Performance IQ = 126.5) and current phonological problems. In comparison to an age- and IQ-matched control group, the group with dyslexia showed deficits in two tasks associated with magnocellular/dorsal pathway function. For the 'frequency doubling' stimulus (grating of 0.25 cpd modulated at 25 Hz counterphase flicker), contrast thresholds for detection were raised in the dyslexic group. In conjunction visual search, a display time sufficient for controls to achieve ceiling accuracy at all set sizes (30 ms per item) was inadequate to allow shifts of attention around the display for the group with dyslexia. In contrast, normal performance was found on 'popout' visual search and on a ventral stream acuity task. Correlational analysis revealed a significant relationship between degree of deficit in conjunction search and phonological difficulty. The deficits revealed were specific to functions that rely on magnocellular input. They cannot be attributed to concentration lapses, eye movement problems or slow reaction times in the dyslexic group.

  13. Retinal and visual system: occupational and environmental toxicology.

    PubMed

    Fox, Donald A

    2015-01-01

    Occupational chemical exposure often results in sensory systems alterations that occur without other clinical signs or symptoms. Approximately 3000 chemicals are toxic to the retina and central visual system. Their dysfunction can have immediate, long-term, and delayed effects on mental health, physical health, and performance and lead to increased occupational injuries. The aims of this chapter are fourfold. First, provide references on retinal/visual system structure, function, and assessment techniques. Second, discuss the retinal features that make it especially vulnerable to toxic chemicals. Third, review the clinical and corresponding experimental data regarding retinal/visual system deficits produced by occupational toxicants: organic solvents (carbon disulfide, trichloroethylene, tetrachloroethylene, styrene, toluene, and mixtures) and metals (inorganic lead, methyl mercury, and mercury vapor). Fourth, discuss occupational and environmental toxicants as risk factors for late-onset retinal diseases and degeneration. Overall, the toxicants altered color vision, rod- and/or cone-mediated electroretinograms, visual fields, spatial contrast sensitivity, and/or retinal thickness. The findings elucidate the importance of conducting multimodal noninvasive clinical, electrophysiologic, imaging and vision testing to monitor toxicant-exposed workers for possible retinal/visual system alterations. Finally, since the retina is a window into the brain, an increased awareness and understanding of retinal/visual system dysfunction should provide additional insight into acquired neurodegenerative disorders.

  14. Voluntary physical exercise promotes ocular dominance plasticity in adult mouse primary visual cortex.

    PubMed

    Kalogeraki, Evgenia; Greifzu, Franziska; Haack, Franziska; Löwel, Siegrid

    2014-11-12

    Ocular dominance (OD) plasticity in the mouse primary visual cortex (V1) declines during aging and is absent beyond postnatal day (P) 110 when mice are raised in standard cages (SCs; Lehmann and Löwel, 2008). In contrast, raising mice in an enriched environment (EE) preserved a juvenile-like OD plasticity into late adulthood (Greifzu et al., 2014). EE raising provides the mice with more social interactions, voluntary physical exercise, and cognitive stimulation compared with SC, raising the question whether all components are needed or whether one of them is already sufficient to prolong plasticity. To test whether voluntary physical exercise alone already prolongs the sensitive phase for OD plasticity, we raised mice from 7 d before birth to adulthood in slightly larger than normal SCs with or without a running wheel (RW). When the mice were older than P135, we visualized V1 activity before and after monocular deprivation (MD) using intrinsic signal optical imaging. Adult RW-raised mice continued to show an OD shift toward the open eye after 7 d of MD, while age-matched SC mice without a RW did not show OD plasticity. Notably, running just during the 7 d MD period restored OD plasticity in adult SC-raised mice. In addition, the OD shift of the RW mice was mediated by a decrease of deprived-eye responses in V1, a signature of "juvenile-like" plasticity. We conclude that voluntary physical exercise alone is sufficient to promote plasticity in adult mouse V1.

  15. Sunfall: a collaborative visual analytics system for astrophysics

    SciTech Connect

    Aragon, Cecilia R.; Aragon, Cecilia R.; Bailey, Stephen J.; Poon, Sarah; Runge, Karl; Thomas, Rollin C.

    2008-07-07

    Computational and experimental sciences produce and collect ever-larger and complex datasets, often in large-scale, multi-institution projects. The inability to gain insight into complex scientific phenomena using current software tools is a bottleneck facing virtually all endeavors of science. In this paper, we introduce Sunfall, a collaborative visual analytics system developed for the Nearby Supernova Factory, an international astrophysics experiment and the largest data volume supernova search currently in operation. Sunfall utilizes novel interactive visualization and analysis techniques to facilitate deeper scientific insight into complex, noisy, high-dimensional, high-volume, time-critical data. The system combines novel image processing algorithms, statistical analysis, and machine learning with highly interactive visual interfaces to enable collaborative, user-driven scientific exploration of supernova image and spectral data. Sunfall is currently in operation at the Nearby Supernova Factory; it is the first visual analytics system in production use at a major astrophysics project.

  16. The Two Visual Systems Hypothesis: New Challenges and Insights from Visual form Agnosic Patient DF

    PubMed Central

    Whitwell, Robert L.; Milner, A. David; Goodale, Melvyn A.

    2014-01-01

    Patient DF, who developed visual form agnosia following carbon monoxide poisoning, is still able to use vision to adjust the configuration of her grasping hand to the geometry of a goal object. This striking dissociation between perception and action in DF provided a key piece of evidence for the formulation of Goodale and Milner’s Two Visual Systems Hypothesis (TVSH). According to the TVSH, the ventral stream plays a critical role in constructing our visual percepts, whereas the dorsal stream mediates the visual control of action, such as visually guided grasping. In this review, we discuss recent studies of DF that provide new insights into the functional organization of the dorsal and ventral streams. We confirm recent evidence that DF has dorsal as well as ventral brain damage – and that her dorsal-stream lesions and surrounding atrophy have increased in size since her first published brain scan. We argue that the damage to DF’s dorsal stream explains her deficits in directing actions at targets in the periphery. We then focus on DF’s ability to accurately adjust her in-flight hand aperture to changes in the width of goal objects (grip scaling) whose dimensions she cannot explicitly report. An examination of several studies of DF’s grip scaling under natural conditions reveals a modest though significant deficit. Importantly, however, she continues to show a robust dissociation between form vision for perception and form vision-for-action. We also review recent studies that explore the role of online visual feedback and terminal haptic feedback in the programming and control of her grasping. These studies make it clear that DF is no more reliant on visual or haptic feedback than are neurologically intact individuals. In short, we argue that her ability to grasp objects depends on visual feedforward processing carried out by visuomotor networks in her dorsal stream that function in the much the same way as they do in neurologically intact individuals

  17. Interactive visual steering--rapid visual prototyping of a common rail injection system.

    PubMed

    Matković, Kresimir; Gracanin, Denis; Jelović, Mario; Hauser, Helwig

    2008-01-01

    Interactive steering with visualization has been a common goal of the visualization research community for twenty years, but it is rarely ever realized in practice. In this paper we describe a successful realization of a tightly coupled steering loop, integrating new simulation technology and interactive visual analysis in a prototyping environment for automotive industry system design. Due to increasing pressure on car manufacturers to meet new emission regulations, to improve efficiency, and to reduce noise, both simulation and visualization are pushed to their limits. Automotive system components, such as the powertrain system or the injection system have an increasing number of parameters, and new design approaches are required. It is no longer possible to optimize such a system solely based on experience or forward optimization. By coupling interactive visualization with the simulation back-end (computational steering), it is now possible to quickly prototype a new system, starting from a non-optimized initial prototype and the corresponding simulation model. The prototyping continues through the refinement of the simulation model, of the simulation parameters and through trial-and-error attempts to an optimized solution. The ability to early see the first results from a multidimensional simulation space--thousands of simulations are run for a multidimensional variety of input parameters--and to quickly go back into the simulation and request more runs in particular parameter regions of interest significantly improves the prototyping process and provides a deeper understanding of the system behavior. The excellent results which we achieved for the common rail injection system strongly suggest that our approach has a great potential of being generalized to other, similar scenarios.

  18. Anatomy and physiology of the afferent visual system.

    PubMed

    Prasad, Sashank; Galetta, Steven L

    2011-01-01

    The efficient organization of the human afferent visual system meets enormous computational challenges. Once visual information is received by the eye, the signal is relayed by the retina, optic nerve, chiasm, tracts, lateral geniculate nucleus, and optic radiations to the striate cortex and extrastriate association cortices for final visual processing. At each stage, the functional organization of these circuits is derived from their anatomical and structural relationships. In the retina, photoreceptors convert photons of light to an electrochemical signal that is relayed to retinal ganglion cells. Ganglion cell axons course through the optic nerve, and their partial decussation in the chiasm brings together corresponding inputs from each eye. Some inputs follow pathways to mediate pupil light reflexes and circadian rhythms. However, the majority of inputs arrive at the lateral geniculate nucleus, which relays visual information via second-order neurons that course through the optic radiations to arrive in striate cortex. Feedback mechanisms from higher cortical areas shape the neuronal responses in early visual areas, supporting coherent visual perception. Detailed knowledge of the anatomy of the afferent visual system, in combination with skilled examination, allows precise localization of neuropathological processes and guides effective diagnosis and management of neuro-ophthalmic disorders.

  19. Associating peripheral and foveal visual input across saccades: a default mode of the human visual system?

    PubMed

    Weiß, Katharina; Schneider, Werner X; Herwig, Arvid

    2014-09-09

    Spatial processing resolution of a particular object in the visual field can differ considerably due to eye movements. The same object will be represented with high acuity in the fovea but only coarsely in periphery. Herwig and Schneider (in press) proposed that the visual system counteracts such resolution differences by predicting, based on previous experience, how foveal objects will look in the periphery and vice versa. They demonstrated that previously learned transsaccadic associations between peripheral and foveal object information facilitate performance in visual search, irrespective of the correctness of these associations. False associations were learned by replacing the presaccadic object with a slightly different object during the saccade. Importantly, participants usually did not notice this object change. This raises the question of whether perception of object continuity is a critical factor in building transsaccadic associations. We disturbed object continuity during learning with a postsaccadic blank or a task-irrelevant shape change. Interestingly, visual search performance revealed that neither disruption of temporal object continuity (blank) nor disruption of spatial object continuity (shape change) impaired transsaccadic learning. Thus, transsaccadic learning seems to be a very robust default mechanism of the visual system that is probably related to the more general concept of action-effect learning.

  20. Defining the cortical visual systems: "what", "where", and "how"

    NASA Technical Reports Server (NTRS)

    Creem, S. H.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

    2001-01-01

    The visual system historically has been defined as consisting of at least two broad subsystems subserving object and spatial vision. These visual processing streams have been organized both structurally as two distinct pathways in the brain, and functionally for the types of tasks that they mediate. The classic definition by Ungerleider and Mishkin labeled a ventral "what" stream to process object information and a dorsal "where" stream to process spatial information. More recently, Goodale and Milner redefined the two visual systems with a focus on the different ways in which visual information is transformed for different goals. They relabeled the dorsal stream as a "how" system for transforming visual information using an egocentric frame of reference in preparation for direct action. This paper reviews recent research from psychophysics, neurophysiology, neuropsychology and neuroimaging to define the roles of the ventral and dorsal visual processing streams. We discuss a possible solution that allows for both "where" and "how" systems that are functionally and structurally organized within the posterior parietal lobe.

  1. Synchronization trigger control system for flow visualization

    NASA Technical Reports Server (NTRS)

    Chun, K. S.

    1987-01-01

    The use of cinematography or holographic interferometry for dynamic flow visualization in an internal combustion engine requires a control device that globally synchronizes camera and light source timing at a predefined shaft encoder angle. The device is capable of 0.35 deg resolution for rotational speeds of up to 73 240 rpm. This was achieved by implementing the shaft encoder signal addressed look-up table (LUT) and appropriate latches. The developed digital signal processing technique achieves 25 nsec of high speed triggering angle detection by using direct parallel bit comparison of the shaft encoder digital code with a simulated angle reference code, instead of using angle value comparison which involves more complicated computation steps. In order to establish synchronization to an AC reference signal whose magnitude is variant with the rotating speed, a dynamic peak followup synchronization technique has been devised. This method scrutinizes the reference signal and provides the right timing within 40 nsec. Two application examples are described.

  2. The Orbital Maneuvering Vehicle Training Facility visual system concept

    NASA Technical Reports Server (NTRS)

    Williams, Keith

    1989-01-01

    The purpose of the Orbital Maneuvering Vehicle (OMV) Training Facility (OTF) is to provide effective training for OMV pilots. A critical part of the training environment is the Visual System, which will simulate the video scenes produced by the OMV Closed-Circuit Television (CCTV) system. The simulation will include camera models, dynamic target models, moving appendages, and scene degradation due to the compression/decompression of video signal. Video system malfunctions will also be provided to ensure that the pilot is ready to meet all challenges the real-world might provide. One possible visual system configuration for the training facility that will meet existing requirements is described.

  3. Visual disturbance with systemic symptoms: old lessons revisited.

    PubMed

    Hume, Megan E; Fernandes, Peter M; MacLean, Kirsty; McRorie, Euan; Davenport, Richard

    2016-10-25

    We describe a retired physician who presented with visual disturbance and systemic symptoms. The presence of general malaise, headache and scalp tenderness, with raised inflammatory markers, suggested that giant cell arteritis (GCA) was the likely diagnosis. Rapid response to initial steroid therapy and histological evidence of inflammation in the temporal artery supported this diagnosis. The character of these visual symptoms was, however, atypical for GCA. The patient, who had heart valve disease, subsequently deteriorated and developed further symptoms warranting investigation of bacterial endocarditis. Retinal emboli are a recognised complication of endocarditis, which could account for these visual symptoms. Moreover, interpretation of the temporal artery biopsy is limited in the context of existing steroid therapy. Our patient was consequently diagnosed with bacterial endocarditis. This case reminds us to consider the wider differential diagnoses for headache, visual disturbance and systemic symptoms, where echocardiogram and blood cultures may be crucial to reach the diagnosis.

  4. Rapidly Building Visual Management Systems for Context-Aware Services

    NASA Astrophysics Data System (ADS)

    Satoh, Ichiro

    A component framework for building and operating visual interfaces for context-aware services in ubiquitous computing environments is presented. By using a compound-document technology, it provides physical entities, places, stationary or mobile computing devices, and services with visual components as multimedia representations to enable them to be annotated and controlled them. It can automatically assemble visual components into a visual interface for monitoring and managing context-aware services according to the spatial-containment relationships between their targets in the physical world by using underlying location-sensing systems. End-users can manually deploy and customize context-aware services through user-friendly GUI-based manipulations for editing documents. This paper presents the design for this framework and describes its implementation and practical applications in user/location-aware assistant systems in two museums.

  5. CAVASS: a computer assisted visualization and analysis software system - visualization aspects

    NASA Astrophysics Data System (ADS)

    Grevera, George; Udupa, Jayaram; Odhner, Dewey; Zhuge, Ying; Souza, Andre; Iwanaga, Tad; Mishra, Shipra

    2007-03-01

    The Medical Image Processing Group (MIPG) at the University of Pennsylvania has been developing and distributing medical image analysis and visualization software systems for a long period of time. Our most recent system, 3DVIEWNIX, was first released in 1993. Since that time, a number of significant advancements have taken place with regard to computer platforms and operating systems, networking capability, the rise of parallel processing standards, and the development of open source toolkits. The development of CAVASS by our group is the next generation of 3DVIEWNIX. CAVASS will be freely available, open source, and is integrated with toolkits such as ITK and VTK. CAVASS runs on Windows, Unix, and Linux but shares a single code base. Rather than requiring expensive multiprocessor systems, it seamlessly provides for parallel processing via inexpensive COWs (Cluster of Workstations) for more time consuming algorithms. Most importantly, CAVASS is directed at the visualization, processing, and analysis of medical imagery, so support for 3D and higher dimensional medical image data and the efficient implementation of algorithms is given paramount importance. This paper focuses on aspects of visualization. All of the most of the popular modes of visualization including various 2D slice modes, reslicing, MIP, surface rendering, volume rendering, and animation are incorporated into CAVASS.

  6. Joint coordination in young and older adults during quiet stance: effect of visual feedback of the center of pressure.

    PubMed

    Freitas, Sandra Maria Sbeghen Ferreira; Duarte, Marcos

    2012-01-01

    How aging affects body sway and joint coordination during quiet standing was investigated under two visual feedback conditions provided on a monitor screen: fixed and moving cursor representing the center of pressure (COP) position measured by a platform. The across-time joint motion variance of ankle, knee, hip, mid-trunk, and cervical spine leading to COP displacement was analyzed using the uncontrolled manifold approach. The body sway was assessed by the COP displacement. Young and older adults showed greater ankle joint contribution to COP displacement than the other joints. However, older adults showed larger variability of knee and mid-trunk joint motions than young adults. During the moving condition, the ankle joint contribution decreased and hip joint contribution increased for both groups, but the COP displacement increased only for the older adults. We conclude that joint coordination and body sway during quiet standing can be modified by providing COP visual feedback and that joint coordination is affected by aging.

  7. Stereoscopic Displays And The Human Dual Visual System

    NASA Astrophysics Data System (ADS)

    Clapp, Robert E.

    1986-05-01

    There is only one real world. We "see" that world as extending into three dimensions because we look at it with two visual systems and with two eyes. We are not presented with two "pictures" of the real world, but with two separate sets of inputs into two separate systems. The analog of the eye as a camera has been a constant problem in the visualization of the "seeing" process. Overcoming the persistence of such an approach is the first requirement in developing a true stereoscopic display system. The eye is a dynamic sensing apparatus and supplies the brain with visual inputs. The brain constructs the scene we "see", and is responsible for our perceptions of the visual world. The sensory inputs from the human dual visual system (Ambient - wide FOV, Focal - detail FOV) are combined with other body senses in this perceptual process. Indeed, other body senses, in some degree, direct and control where and at what our eyes look. This process of conceptualization of the "real" world as perceived by ourselves can be related only within limits to the "real" world as perceived by others.. This paper addresses the processes by which our minds (with sensor inputs) work to form our stereoscopic perceptual concepts of the world, real or simulated, and the advantages (and problems) caused by our egocentric reduction of those data inputs. Discussion and evaluation of stereoscopic display systems compares current and future display systems.

  8. Initial Evaluations of Mainstream Personality Tests for Use with Visually Impaired Adults in Vocational Assessment and Guidance.

    ERIC Educational Resources Information Center

    Reid, Juliet

    2000-01-01

    This article reviews the Eysenck Personality Questionnaire-Revised (EPQ-R adult and EPQ-R short form), the 16PF5, and the Myers-Briggs Type Indicator for use with adults with visual impairments. Results found only the EPQ-R short form can be used by participants using low vision aids, closed-circuit television, or an optical character reader.…

  9. Visual statistical learning is related to natural language ability in adults: An ERP study.

    PubMed

    Daltrozzo, Jerome; Emerson, Samantha N; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M

    2017-03-01

    Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities.

  10. Adaptation-induced modification of motion selectivity tuning in visual tectal neurons of adult zebrafish

    PubMed Central

    Lucks, Valerie; Kurtz, Rafael; Engelmann, Jacob

    2015-01-01

    In the developing brain, training-induced emergence of direction selectivity and plasticity of orientation tuning appear to be widespread phenomena. These are found in the visual pathway across different classes of vertebrates. Moreover, short-term plasticity of orientation tuning in the adult brain has been demonstrated in several species of mammals. However, it is unclear whether neuronal orientation and direction selectivity in nonmammalian species remains modifiable through short-term plasticity in the fully developed brain. To address this question, we analyzed motion tuning of neurons in the optic tectum of adult zebrafish by calcium imaging. In total, orientation and direction selectivity was enhanced by adaptation, responses of previously orientation-selective neurons were sharpened, and even adaptation-induced emergence of selectivity in previously nonselective neurons was observed in some cases. The different observed effects are mainly based on the relative distance between the previously preferred and the adaptation direction. In those neurons in which a shift of the preferred orientation or direction was induced by adaptation, repulsive shifts (i.e., away from the adapter) were more prevalent than attractive shifts. A further novel finding for visually induced adaptation that emerged from our study was that repulsive and attractive shifts can occur within one brain area, even with uniform stimuli. The type of shift being induced also depends on the difference between the adapting and the initially preferred stimulus direction. Our data indicate that, even within the fully developed optic tectum, short-term plasticity might have an important role in adjusting neuronal tuning functions to current stimulus conditions. PMID:26378206

  11. Stereoscopy and the Human Visual System

    PubMed Central

    Banks, Martin S.; Read, Jenny C. A.; Allison, Robert S.; Watt, Simon J.

    2012-01-01

    Stereoscopic displays have become important for many applications, including operation of remote devices, medical imaging, surgery, scientific visualization, and computer-assisted design. But the most significant and exciting development is the incorporation of stereo technology into entertainment: specifically, cinema, television, and video games. In these applications for stereo, three-dimensional (3D) imagery should create a faithful impression of the 3D structure of the scene being portrayed. In addition, the viewer should be comfortable and not leave the experience with eye fatigue or a headache. Finally, the presentation of the stereo images should not create temporal artifacts like flicker or motion judder. This paper reviews current research on stereo human vision and how it informs us about how best to create and present stereo 3D imagery. The paper is divided into four parts: (1) getting the geometry right, (2) depth cue interactions in stereo 3D media, (3) focusing and fixating on stereo images, and (4) how temporal presentation protocols affect flicker, motion artifacts, and depth distortion. PMID:23144596

  12. Audio-visual speech perception in adult readers with dyslexia: an fMRI study.

    PubMed

    Rüsseler, Jascha; Ye, Zheng; Gerth, Ivonne; Szycik, Gregor R; Münte, Thomas F

    2017-03-13

    Developmental dyslexia is a specific deficit in reading and spelling that often persists into adulthood. In the present study, we used slow event-related fMRI and independent component analysis to identify brain networks involved in perception of audio-visual speech in a group of adult readers with dyslexia (RD) and a group of fluent readers (FR). Participants saw a video of a female speaker saying a disyllabic word. In the congruent condition, audio and video input were identical whereas in the incongruent condition, the two inputs differed. Participants had to respond to occasionally occurring animal names. The independent components analysis (ICA) identified several components that were differently modulated in FR and RD. Two of these components including fusiform gyrus and occipital gyrus showed less activation in RD compared to FR possibly indicating a deficit to extract face information that is needed to integrate auditory and visual information in natural speech perception. A further component centered on the superior temporal sulcus (STS) also exhibited less activation in RD compared to FR. This finding is corroborated in the univariate analysis that shows less activation in STS for RD compared to FR. These findings suggest a general impairment in recruitment of audiovisual processing areas in dyslexia during the perception of natural speech.

  13. Frequent Self-Weighing and Visual Feedback for Weight Loss in Overweight Adults

    PubMed Central

    Pacanowski, Carly R.; Levitsky, David A.

    2015-01-01

    Evidence has suggested that self-weighing may be beneficial for weight control in adults, but few studies have independently assessed the contribution of this behavior to weight loss. This study experimentally tested daily self-weighing and visual feedback (the Caloric Titration Method (CTM)) as a weight loss and weight loss maintenance intervention over 2 years. 162 overweight individuals were randomized to the CTM intervention or delayed treatment control group. In year 1, weight change was compared between groups, and in year 2, the control group started using the CTM while the intervention group continued using the CTM for maintenance. A significant difference in weight loss over the first year (CTM n = 70; 2.6 ± 5.9 kg versus control n = 65; 0.5 ± 4.4 kg, p = 0.019) was qualified by a group × gender × time interaction (p = 0.002) such that men lost more weight using the CTM. In year 2, the CTM group maintained their weight and the control group lost an amount similar to the intervention group in year 1. Daily self-weighing and visual feedback facilitated a minimal amount of weight loss and maintenance of this loss. Future research investigating characteristics of those who benefit from this type of self-directed intervention is warranted. PMID:26064677

  14. Visual gravitational motion and the vestibular system in humans

    PubMed Central

    Lacquaniti, Francesco; Bosco, Gianfranco; Indovina, Iole; La Scaleia, Barbara; Maffei, Vincenzo; Moscatelli, Alessandro; Zago, Myrka

    2013-01-01

    The visual system is poorly sensitive to arbitrary accelerations, but accurately detects the effects of gravity on a target motion. Here we review behavioral and neuroimaging data about the neural mechanisms for dealing with object motion and egomotion under gravity. The results from several experiments show that the visual estimates of a target motion under gravity depend on the combination of a prior of gravity effects with on-line visual signals on target position and velocity. These estimates are affected by vestibular inputs, and are encoded in a visual-vestibular network whose core regions lie within or around the Sylvian fissure, and are represented by the posterior insula/retroinsula/temporo-parietal junction. This network responds both to target motions coherent with gravity and to vestibular caloric stimulation in human fMRI studies. Transient inactivation of the temporo-parietal junction selectively disrupts the interception of targets accelerated by gravity. PMID:24421761

  15. Plasticity and stability of the visual system in human achiasma

    PubMed Central

    Hoffmann, M.B.; Kaule, F.R.; Levin, N.; Masuda, Y.; Kumar, A.; Gottlob, I.; Horiguchi, H.; Dougherty, R.F.; Stadler, J.; Wolynski, B.; Speck, O.; Kanowski, M.; Liao, Y.J.; Wandell, B.A.

    2012-01-01

    Summary The absence of the optic chiasm is an extraordinary and extreme abnormality in the nervous system. The abnormality produces highly atypical functional responses in the cortex, including overlapping hemifield representations and bilateral population receptive fields in both striate and extrastriate visual cortex. Even in the presence of these large functional abnormalities, the effect on visual perception and daily life is not easily detected. Here we demonstrate that in two achiasmic humans the gross topography of the geniculo-striate and occipital callosal connections remains largely unaltered. We conclude that visual function is preserved by reorganization of intra-cortical connections instead of large-scale reorganizations of the visual cortex. Thus developmental mechanisms of local wiring within cortical maps compensate for the improper gross wiring to preserve function in human achiasma. PMID:22884323

  16. Plasticity and stability of the visual system in human achiasma.

    PubMed

    Hoffmann, Michael B; Kaule, Falko R; Levin, Netta; Masuda, Yoichiro; Kumar, Anil; Gottlob, Irene; Horiguchi, Hiroshi; Dougherty, Robert F; Stadler, Joerg; Wolynski, Barbara; Speck, Oliver; Kanowski, Martin; Liao, Yaping J; Wandell, Brian A; Dumoulin, Serge O

    2012-08-09

    The absence of the optic chiasm is an extraordinary and extreme abnormality in the nervous system. The abnormality produces highly atypical functional responses in the cortex, including overlapping hemifield representations and bilateral population receptive fields in both striate and extrastriate visual cortex. Even in the presence of these large functional abnormalities, the effect on visual perception and daily life is not easily detected. Here, we demonstrate that in two achiasmic humans the gross topography of the geniculostriate and occipital callosal connections remains largely unaltered. We conclude that visual function is preserved by reorganization of intracortical connections instead of large-scale reorganizations of the visual cortex. Thus, developmental mechanisms of local wiring within cortical maps compensate for the improper gross wiring to preserve function in human achiasma.

  17. 47 CFR 87.483 - Audio visual warning systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... audio visual warning system (AVWS) is a radar-based obstacle avoidance system. AVWS activates... exist. The continuously operating radar calculates the location, direction and groundspeed of nearby... obstacle. (a) Radiodetermination (radar) frequencies. Frequencies authorized under § 87.475(b)(8) of...

  18. Competition and Homeostasis of Excitatory and Inhibitory Connectivity in the Adult Mouse Visual Cortex.

    PubMed

    Saiepour, M Hadi; Chakravarthy, Sridhara; Min, Rogier; Levelt, Christiaan N

    2015-10-01

    During cortical development, synaptic competition regulates the formation and adjustment of neuronal connectivity. It is unknown whether synaptic competition remains active in the adult brain and how inhibitory neurons participate in this process. Using morphological and electrophysiological measurements, we show that expressing a dominant-negative form of the TrkB receptor (TrkB.T1) in the majority of pyramidal neurons in the adult visual cortex does not affect excitatory synapse densities. This is in stark contrast to the previously reported loss of excitatory input which occurs if the exact same transgene is expressed in sparse neurons at the same age. This indicates that synaptic competition remains active in adulthood. Additionally, we show that interneurons not expressing the TrkB.T1 transgene may have a competitive advantage and obtain more excitatory synapses when most neighboring pyramidal neurons do express the transgene. Finally, we demonstrate that inhibitory synapses onto pyramidal neurons are reduced when TrkB signaling is interfered with in most pyramidal neurons but not when few pyramidal neurons have this deficit. This adjustment of inhibitory innervation is therefore not a cell-autonomous consequence of decreased TrkB signaling but more likely a homeostatic mechanism compensating for activity changes at the population level.

  19. The shared signal hypothesis: effects of emotion-gaze congruency in infant and adult visual preferences.

    PubMed

    Rigato, Silvia; Menon, Enrica; Farroni, Teresa; Johnson, Mark H

    2013-03-01

    In this study, 4-month-old infants' and adults' spontaneous preferences for emotional and neutral displays with direct and averted gaze are investigated using visual preference paradigms. Specifically, by presenting two approach-oriented emotions (happiness and anger) and two avoidance-oriented emotions (fear and sadness), we asked whether the pattern of emotion-gaze interaction suggested by the shared signal hypothesis (SSH) would also be found with this paradigm. Both age groups demonstrated an ability to discern the approach- and avoidance-oriented emotions, matching them with direct and averted gaze, respectively. Nonetheless, infants showed a greater sensitivity for the congruent emotion-gaze combination in the approach-oriented emotions, while adults were equally sensitive to the gaze-expression congruence for both the approach- and avoidance-oriented emotions. In a follow-up experiment, infants showed no preference for direct or averted gaze in the context of neutral faces. We conclude that the SSH may have validity from infancy, gradually extending from approach-oriented emotions to avoidance-oriented emotions over the course of development.

  20. Retinal waves coordinate patterned activity throughout the developing visual system

    PubMed Central

    Ackman, James B.; Burbridge, Timothy J.; Crair, Michael C.

    2014-01-01

    Summary The morphologic and functional development of the vertebrate nervous system is initially governed by genetic factors and subsequently refined by neuronal activity. However, fundamental features of the nervous system emerge before sensory experience is possible. Thus, activity-dependent development occurring before the onset of experience must be driven by spontaneous activity, but the origin and nature of activity in vivo remains largely untested. Here we use optical methods to demonstrate in live neonatal mice that waves of spontaneous retinal activity are present and propagate throughout the entire visual system before eye opening. This patterned activity encompassed the visual field, relied on cholinergic neurotransmission, preferentially initiated in the binocular retina, and exhibited spatiotemporal correlations between the two hemispheres. Retinal waves were the primary source of activity in the midbrain and primary visual cortex, but only modulated ongoing activity in secondary visual areas. Thus, spontaneous retinal activity is transmitted through the entire visual system and carries patterned information capable of guiding the activity-dependent development of complex intra- and inter- hemispheric circuits before the onset of vision. PMID:23060192

  1. Retinal waves coordinate patterned activity throughout the developing visual system.

    PubMed

    Ackman, James B; Burbridge, Timothy J; Crair, Michael C

    2012-10-11

    The morphological and functional development of the vertebrate nervous system is initially governed by genetic factors and subsequently refined by neuronal activity. However, fundamental features of the nervous system emerge before sensory experience is possible. Thus, activity-dependent development occurring before the onset of experience must be driven by spontaneous activity, but the origin and nature of activity in vivo remains largely untested. Here we use optical methods to show in live neonatal mice that waves of spontaneous retinal activity are present and propagate throughout the entire visual system before eye opening. This patterned activity encompassed the visual field, relied on cholinergic neurotransmission, preferentially initiated in the binocular retina and exhibited spatiotemporal correlations between the two hemispheres. Retinal waves were the primary source of activity in the midbrain and primary visual cortex, but only modulated ongoing activity in secondary visual areas. Thus, spontaneous retinal activity is transmitted through the entire visual system and carries patterned information capable of guiding the activity-dependent development of complex intra- and inter-hemispheric circuits before the onset of vision.

  2. Adult age-dependent differences in resting-state connectivity within and between visual-attention and sensorimotor networks

    PubMed Central

    Roski, Christian; Caspers, Svenja; Langner, Robert; Laird, Angela R.; Fox, Peter T.; Zilles, Karl; Amunts, Katrin; Eickhoff, Simon B.

    2013-01-01

    Healthy aging is accompanied by structural and functional changes in the brain, among which a loss of neural specificity (i.e., dedifferentiation) is one of the most consistent findings. Little is known, however, about changes in interregional integration underlying a dedifferentiation across different functional systems. In a large sample (n = 399) of healthy adults aged from 18 to 85 years, we analyzed age-dependent differences in resting-state (RS) (task-independent) functional connectivity (FC) of a set of brain regions derived from a previous fMRI study. In that study, these regions had shown an age-related loss of activation specificity in visual-attention (superior parietal area 7A and dorsal premotor cortex) or sensorimotor (area OP4 of the parietal operculum) tasks. In addition to these dedifferentiated regions, the FC analysis of the present study included “task-general” regions associated with both attention and sensorimotor systems (rostral supplementary motor area and bilateral anterior insula) as defined via meta-analytical co-activation mapping. Within this network, we observed both selective increases and decreases in RS-FC with age. In line with regional activation changes reported previously, we found diminished anti-correlated FC for inter-system connections (i.e., between sensorimotor-related and visual attention-related regions). Our analysis also revealed reduced FC between system-specific and task-general regions, which might reflect age-related deficits in top-down control possibly leading to dedifferentiation of task-specific brain activity. Together, our results underpin the notion that RS-FC changes concur with regional activity changes in the healthy aging brain, presumably contributing jointly to age-related behavioral changes. PMID:24194718

  3. The Role of Diverse Institutions in Framing Adult Learning Systems

    ERIC Educational Resources Information Center

    Saar, Ellu; Ure, Odd Bjorn; Desjardins, Richard

    2013-01-01

    This article considers the role of diverse institutions in framing adult learning systems. The focus is on institutional characteristics and configurations in different countries and their potential impact on the extent of adult learning, as well as on inequalities in access to adult learning. Typologies of education and training systems as well…

  4. The System of Adult Education in Yugoslavia. Notes and Essays on Education for Adults, 59.

    ERIC Educational Resources Information Center

    Savicevic, Dusan M.

    Now an integral part of the Yugoslav national educational system, adult education in Yugoslavia is based on the principles of permanence, democracy, decentralization, functional unity, diversity and dynamism, and voluntarism. Adult basic, vocational, general, and other forms of adult education are offered in varying degrees and forms by primary…

  5. The prevalence and causes of visual impairment and blindness among older adults in the city of Lodz, Poland.

    PubMed

    Nowak, Michal S; Smigielski, Janusz

    2015-02-01

    To investigate the prevalence and causes of visual impairment and blindness in a sample of Polish older adults. The study was designed in a cross-sectional and observational manner. Data concerning the vision status were assessed in 2214 eyes from 1107 subjects of European Caucasian origin; most of whom live in the city of Lodz, in central Poland. Visual impairment was defined as distance visual acuity <20/40 in the worse-seeing eye. Low vision was defined as best-corrected visual acuity (BCVA) <20/40 but >20/200 in better-seeing eye, and blindness was defined as BCVA ≤20/200 in both eyes (United States criteria). Visual impairment was found in 27.5% subjects in the worse-seeing eye. Multiple regression analysis showed that increasing age (OR 0.98, 95% CI 0.97-0.99) and female gender (OR 1.47, 95% CI 1.11-1.93) were independent risk factors. No association was found between visual impairment and socioeconomic status of subjects. Noncorrectable visual impairment was found in 7.0% of subjects, including 5.2% of subjects with unilateral and 1.8% of subjects with bilateral visual impairment. Low vision and blindness accounted for 1.3% and 0.5%, respectively, and were only associated with older age (OR 1.05, 95% CI 1.02-1.10). Retinal diseases represented the major cause of noncorrectable visual impairment and accounted for more than half of causes of blindness. Provision of appropriate refractive correction improves visual acuity in 75% subjects presenting with visual impairment. Retinal diseases are a major cause of noncorrectable visual impairment and blindness in this older population.

  6. Practice Makes Improvement: How Adults with Autism Out-Perform Others in a Naturalistic Visual Search Task

    ERIC Educational Resources Information Center

    Gonzalez, Cleotilde; Martin, Jolie M.; Minshew, Nancy J.; Behrmann, Marlene

    2013-01-01

    People with autism spectrum disorder (ASD) often exhibit superior performance in visual search compared to others. However, most studies demonstrating this advantage have employed simple, uncluttered images with fully visible targets. We compare the performance of high-functioning adults with ASD and matched controls on a naturalistic luggage…

  7. Effects of a Psychoeducational Group on Mood and Glycemic Control in Adults with Diabetes and Visual Impairments.

    ERIC Educational Resources Information Center

    Trozzolino, Linda; Thompson, Pamela S.; Tansman, Mara S.; Azen, Stanley P.

    2003-01-01

    This study evaluated the effectiveness of a 12-week psychoeducational group therapy program in improving mood and glycemic control in 48 adults with diabetes and visual impairments. Participants made statistically significant gains in glycemic control. There was a significant positive relationship between control and improvement in depression, but…

  8. Visual Habituation Paradigm with Adults with Profound Intellectual and Multiple Disabilities: A New Way for Cognitive Assessment?

    ERIC Educational Resources Information Center

    Chard, Melissa; Roulin, Jean-Luc; Bouvard, Martine

    2014-01-01

    Background: The use of common psychological assessment tools is invalidated with persons with PIMD. The aim of this study was to test the feasibility of using a visual habituation procedure with a group of adults with PIMD, to develop a new theoretical and practical framework for the assessment of cognitive abilities. Methods: To test the…

  9. Prevalence of Visual Impairments in Adults with Cognitive and Developmental Disabilities in a Sheltered Workshop in Germany

    ERIC Educational Resources Information Center

    Henriksen, Anne; Degenhardt, Sven

    2009-01-01

    Individuals with cognitive and developmental disabilities have a high probability of visual impairment. This study revealed the effects of deficits in the appropriate diagnosis of vision and medical treatment, as well as the lack of necessary refraction correction and support, specifically for adults with intellectual and developmental…

  10. Visually Impaired Older Adults and Home-Based Leisure Activities: The Effects of Person-Environment Congruence

    ERIC Educational Resources Information Center

    Stevens-Ratchford, Regina; Krause, Airi

    2004-01-01

    This qualitative study explored the effect of person-environment congruence on participation in homebased leisure activities by two legally blind older adults who lived independently in the community. The results indicated that visual impairment increased the time spent in home-based leisure activities and that the participants used various…

  11. Adult Outcomes, Reported Self-Aptitude, and Perceived Training: A Follow-Up Study of Individuals with Visual Impairment

    ERIC Educational Resources Information Center

    Lawson, Holly Michelle

    2010-01-01

    The purpose of this study was to examine factors that relate to successful adult outcomes for 28 individuals with visual impairment ages 23-30. The primary dependent variable was current employment. Independent living and completion of postsecondary educational program were secondary, related outcome measures. A secondary goal of this research was…

  12. Visual Systems for Remotely Controlled Vehicles

    NASA Technical Reports Server (NTRS)

    Rezek, T.

    1984-01-01

    The Variable Acuity Remote Viewing System is discussed. It was conceived as a technique for resolving the field of view/resolution/ bandwidth tradeoffs that exist in remote viewing systems. This system is based on the fact that integration of the human eye acuity function shows only about 130,000 pixels are required to fully support the human vision. This quantity is well within the capabilities of conventional video systems. The technique utilizes a non-linear optical system in both the sensing and display equipment. The non-linearity is achieved by a special lens which translates a uniform pixel array on its image plane into the object field as a variable angular array. This lens will record the same angular detail the eye would see when viewing the same scene and compress this detail into a uniform matrix of equal sized picture elements on its image plane. This image can be scanned with a broadcast quality tv having a 525 line raster scan. Conventional transmission equipment can then also be used to send the image information to a remote location. When received, the image is projected by a light valve projector onto a hemispherical screen by an identical non-linear lens.

  13. The unassisted visual system on earth and in space.

    PubMed

    Harris, Laurence R; Jenkin, Michael; Jenkin, Heather; Dyde, Richard; Zacher, Jim; Allison, Robert S

    2010-01-01

    Chuck Oman has been a guide and mentor for research in human perception and performance during space exploration for over 25 years. His research has provided a solid foundation for our understanding of how humans cope with the challenges and ambiguities of sensation and perception in space. In many of the environments associated with work in space the human visual system must operate with unusual combinations of visual and other perceptual cues. On Earth physical acceleration cues are normally available to assist the visual system in interpreting static and dynamic visual features. Here we consider two cases where the visual system is not assisted by such cues. Our first experiment examines perceptual stability when the normally available physical cues to linear acceleration are absent. Our second experiment examines perceived orientation when there is no assistance from the physically sensed direction of gravity. In both cases the effectiveness of vision is paradoxically reduced in the absence of physical acceleration cues. The reluctance to rely heavily on vision represents an important human factors challenge to efficient performance in the space environment.

  14. Design for a Program Visualization System.

    DTIC Science & Technology

    1981-01-01

    Support System B-3 8.3 HIPO Charts B-4 B3.1 Analysis B-4 B4 GREENPRINTs B-5 8.4.1 Analysis B-5 8.5 PYGMALION B-8 8.5.1 Analysis B-8 B.6 The Mini-LOGO... PYGMALION inadequate for programming in "high-order languages." Thus, it is not always easy to express some program- 9 Mini-LOGO animation system...way. using the medium of paper or blackboard, the - GREENPRINTs are being used internally within many PYGMALION programmer uses the display screen

  15. Satellite Imagery Assisted Road-Based Visual Navigation System

    NASA Astrophysics Data System (ADS)

    Volkova, A.; Gibbens, P. W.

    2016-06-01

    There is a growing demand for unmanned aerial systems as autonomous surveillance, exploration and remote sensing solutions. Among the key concerns for robust operation of these systems is the need to reliably navigate the environment without reliance on global navigation satellite system (GNSS). This is of particular concern in Defence circles, but is also a major safety issue for commercial operations. In these circumstances, the aircraft needs to navigate relying only on information from on-board passive sensors such as digital cameras. An autonomous feature-based visual system presented in this work offers a novel integral approach to the modelling and registration of visual features that responds to the specific needs of the navigation system. It detects visual features from Google Earth* build a feature database. The same algorithm then detects features in an on-board cameras video stream. On one level this serves to localise the vehicle relative to the environment using Simultaneous Localisation and Mapping (SLAM). On a second level it correlates them with the database to localise the vehicle with respect to the inertial frame. The performance of the presented visual navigation system was compared using the satellite imagery from different years. Based on comparison results, an analysis of the effects of seasonal, structural and qualitative changes of the imagery source on the performance of the navigation algorithm is presented. * The algorithm is independent of the source of satellite imagery and another provider can be used

  16. Binocular visual integration in the crustacean nervous system.

    PubMed

    Sztarker, Julieta; Tomsic, Daniel

    2004-11-01

    Although the behavioral repertoire of crustaceans is largely guided by visual information their visual nervous system has been little explored. In search for central mechanisms of visual integration, this study was aimed at identifying and characterizing brain neurons in the crab involved in binocular visual processing. The study was performed in the intact animal, by recording intracellularly the response to visual stimuli of neurons from one of the two optic lobes. Identified neurons recorded from the medulla (second optic neuropil), which include sustaining neurons, dimming neurons, depolarizing and hyperpolarizing tonic neurons and on-off neurons, all presented exclusively monocular (ipsilateral) responses. In contrast, all wide field movement detector neurons recorded from the lobula (third optic neuropil) responded to moving stimuli presented to the ipsilateral and to the contralateral eye. In these cells, the responses evoked by ipsilateral or contralateral stimulation were almost identical, as revealed by analysing the number and amplitude of the elicited postsynaptic potentials and spikes, and the ability to habituate upon repeated visual stimulation. The results demonstrate that in crustaceans important binocular processing takes place at the level of the lobula.

  17. The Scalable Reasoning System: Lightweight Visualization for Distributed Analytics

    SciTech Connect

    Pike, William A.; Bruce, Joseph R.; Baddeley, Robert L.; Best, Daniel M.; Franklin, Lyndsey; May, Richard A.; Rice, Douglas M.; Riensche, Roderick M.; Younkin, Katarina

    2008-11-01

    A central challenge in visual analytics is the creation of accessible, widely distributable analysis applications that bring the benefits of visual discovery to as broad a user base as possible. Moreover, to support the role of visualization in the knowledge creation process, it is advantageous to allow users to describe the reasoning strategies they employ while interacting with analytic environments. We introduce an application suite called the Scalable Reasoning System (SRS), which provides web-based and mobile interfaces for visual analysis. The service-oriented analytic framework that underlies SRS provides a platform for deploying pervasive visual analytic environments across an enterprise. SRS represents a “lightweight” approach to visual analytics whereby thin client analytic applications can be rapidly deployed in a platform-agnostic fashion. Client applications support multiple coordinated views while giving analysts the ability to record evidence, assumptions, hypotheses and other reasoning artifacts. We describe the capabilities of SRS in the context of a real-world deployment at a regional law enforcement organization.

  18. Visuals and Visualisation of Human Body Systems

    ERIC Educational Resources Information Center

    Mathai, Sindhu; Ramadas, Jayashree

    2009-01-01

    This paper explores the role of diagrams and text in middle school students' understanding and visualisation of human body systems. We develop a common framework based on structure and function to assess students' responses across diagram and verbal modes. Visualisation is defined in terms of understanding transformations on structure and relating…

  19. Adult Neurogenesis and the Olfactory System

    PubMed Central

    Whitman, Mary C.; Greer, Charles A.

    2009-01-01

    Though initially described in the early 1960s, it is only within the past decade that the concept of continuing adult neurogenesis has gained widespread acceptance. Neuroblasts from the subventricular zone (SVZ) migrate along the rostral migratory stream (RMS) into the olfactory bulb, where they differentiate into interneurons. Neuroblasts from the subgranular zone (SGZ) of the hippocampal formation show relatively little migratory behavior, and differentiate into dentate gyrus granule cells. In sharp contrast to embryonic and perinatal development, these newly differentiated neurons must integrate into a fully functional circuit, without disrupting ongoing performance. Here, after a brief historical overview and introduction to olfactory circuitry, we review recent advances in the biology of neural stem cells, mechanisms of migration in the RMS and olfactory bulb, differentiation and survival of new neurons, and finally mechanisms of synaptic integration. Our primary focus is on the olfactory system, but we also contrast the events occurring there with those in the hippocampal formation. Although both SVZ and SGZ neurogenesis are involved in some types of learning, their full functional significance remains unclear. Since both systems offer models of integration of new neuroblasts, there is immense interest in using neural stem cells to replace neurons lost in injury or disease. Though many questions remain unanswered, new insights appear daily about adult neurogenesis, regulatory mechanisms, and the fates of the progeny. We discuss here some of the central features of these advances, as well as speculate on future research directions. PMID:19615423

  20. Expression and light-triggered movement of rhodopsins in the larval visual system of mosquitoes

    PubMed Central

    Rocha, Manuel; Kimler, Kyle J.; Leming, Matthew T.; Hu, Xiaobang; Whaley, Michelle A.; O'Tousa, Joseph E.

    2015-01-01

    ABSTRACT During the larval stages, the visual system of the mosquito Aedes aegypti contains five stemmata, often referred to as larval ocelli, positioned laterally on each side of the larval head. Here we show that stemmata contain two photoreceptor types, distinguished by the expression of different rhodopsins. The rhodopsin Aaop3 (GPROP3) is expressed in the majority of the larval photoreceptors. There are two small clusters of photoreceptors located within the satellite and central stemmata that express the rhodopsin Aaop7 (GPROP7) instead of Aaop3. Electroretinogram analysis of transgenic Aaop7 Drosophila indicates that Aaop3 and Aaop7, both classified as long-wavelength rhodopsins, possess similar but not identical spectral properties. Light triggers an extensive translocation of Aaop3 from the photosensitive rhabdoms to the cytoplasmic compartment, whereas light-driven translocation of Aaop7 is limited. The results suggest that these photoreceptor cell types play distinct roles in larval vision. An additional component of the larval visual system is the adult compound eye, which starts to develop at the anterior face of the larval stemmata during the 1st instar stage. The photoreceptors of the developing compound eye show rhodopsin expression during the 4th larval instar stage, consistent with indications from previous reports that the adult compound eye contributes to larval and pupal visual capabilities. PMID:25750414

  1. Expression and light-triggered movement of rhodopsins in the larval visual system of mosquitoes.

    PubMed

    Rocha, Manuel; Kimler, Kyle J; Leming, Matthew T; Hu, Xiaobang; Whaley, Michelle A; O'Tousa, Joseph E

    2015-05-01

    During the larval stages, the visual system of the mosquito Aedes aegypti contains five stemmata, often referred to as larval ocelli, positioned laterally on each side of the larval head. Here we show that stemmata contain two photoreceptor types, distinguished by the expression of different rhodopsins. The rhodopsin Aaop3 (GPROP3) is expressed in the majority of the larval photoreceptors. There are two small clusters of photoreceptors located within the satellite and central stemmata that express the rhodopsin Aaop7 (GPROP7) instead of Aaop3. Electroretinogram analysis of transgenic Aaop7 Drosophila indicates that Aaop3 and Aaop7, both classified as long-wavelength rhodopsins, possess similar but not identical spectral properties. Light triggers an extensive translocation of Aaop3 from the photosensitive rhabdoms to the cytoplasmic compartment, whereas light-driven translocation of Aaop7 is limited. The results suggest that these photoreceptor cell types play distinct roles in larval vision. An additional component of the larval visual system is the adult compound eye, which starts to develop at the anterior face of the larval stemmata during the 1st instar stage. The photoreceptors of the developing compound eye show rhodopsin expression during the 4th larval instar stage, consistent with indications from previous reports that the adult compound eye contributes to larval and pupal visual capabilities.

  2. A visually guided collision warning system with a neuromorphic architecture.

    PubMed

    Okuno, Hirotsugu; Yagi, Tetsuya

    2008-12-01

    We have designed a visually guided collision warning system with a neuromorphic architecture, employing an algorithm inspired by the visual nervous system of locusts. The system was implemented with mixed analog-digital integrated circuits consisting of an analog resistive network and field-programmable gate array (FPGA) circuits. The resistive network processes the interaction between the laterally spreading excitatory and inhibitory signals instantaneously, which is essential for real-time computation of collision avoidance with a low power consumption and a compact hardware. The system responded selectively to approaching objects of simulated movie images at close range. The system was, however, confronted with serious noise problems due to the vibratory ego-motion, when it was installed in a mobile miniature car. To overcome this problem, we developed the algorithm, which is also installable in FPGA circuits, in order for the system to respond robustly during the ego-motion.

  3. Research Requirements for Future Visual Guidance Systems

    DTIC Science & Technology

    1994-02-01

    operations at SEATAC International Airport in Washington. Future research efforts will be needed to develop surface guidance systems that will assist air... Airport in Washington State. Because of frequently occurring low-visibility conditions, SEATAC was considered an ideal location for the testing of...been carried out in the United States at JFK Airport in New York in the late 1980’s (reference 21). The costs of retrofitting the SEATAC airport with

  4. A Software-System Visualization Tool

    DTIC Science & Technology

    1990-04-01

    databases. servers) and the dependencies established between these modules (e.g., procedure calls, message passing channels). \\ Ve use the tool to write...A MINION user can view these implicitly constructed connections and notice incorrect links to library modules and "regions" of a graph. We can scale ...configuration programming systems. MINION handles this problem by hiding unimportant details or scaling them graphically. We can graphically select

  5. Living Color Frame System: PC graphics tool for data visualization

    NASA Technical Reports Server (NTRS)

    Truong, Long V.

    1993-01-01

    Living Color Frame System (LCFS) is a personal computer software tool for generating real-time graphics applications. It is highly applicable for a wide range of data visualization in virtual environment applications. Engineers often use computer graphics to enhance the interpretation of data under observation. These graphics become more complicated when 'run time' animations are required, such as found in many typical modern artificial intelligence and expert systems. Living Color Frame System solves many of these real-time graphics problems.

  6. Power spectra of the natural input to the visual system.

    PubMed

    Pamplona, D; Triesch, J; Rothkopf, C A

    2013-05-03

    The efficient coding hypothesis posits that sensory systems are adapted to the regularities of their signal input so as to reduce redundancy in the resulting representations. It is therefore important to characterize the regularities of natural signals to gain insight into the processing of natural stimuli. While measurements of statistical regularity in vision have focused on photographic images of natural environments it has been much less investigated, how the specific imaging process embodied by the organism's eye induces statistical dependencies on the natural input to the visual system. This has allowed using the convenient assumption that natural image data are homogeneous across the visual field. Here we give up on this assumption and show how the imaging process in a human model eye influences the local statistics of the natural input to the visual system across the entire visual field. Artificial scenes with three-dimensional edge elements were generated and the influence of the imaging projection onto the back of a spherical model eye were quantified. These distributions show a strong radial influence of the imaging process on the resulting edge statistics with increasing eccentricity from the model fovea. This influence is further quantified through computation of the second order intensity statistics as a function of eccentricity from the center of projection using samples from the dead leaves image model. Using data from a naturalistic virtual environment, which allows generation of correctly projected images onto the model eye across the entire field of view, we quantified the second order dependencies as function of the position in the visual field using a new generalized parameterization of the power spectra. Finally, we compared this analysis with a commonly used natural image database, the van Hateren database, and show good agreement within the small field of view available in these photographic images. We conclude by providing a detailed

  7. New apparatus of single particle trap system for aerosol visualization

    NASA Astrophysics Data System (ADS)

    Higashi, Hidenori; Fujioka, Tomomi; Endo, Tetsuo; Kitayama, Chiho; Seto, Takafumi; Otani, Yoshio

    2014-08-01

    Control of transport and deposition of charged aerosol particles is important in various manufacturing processes. Aerosol visualization is an effective method to directly observe light scattering signal from laser-irradiated single aerosol particle trapped in a visualization cell. New single particle trap system triggered by light scattering pulse signal was developed in this study. The performance of the device was evaluated experimentally. Experimental setup consisted of an aerosol generator, a differential mobility analyzer (DMA), an optical particle counter (OPC) and the single particle trap system. Polystylene latex standard (PSL) particles (0.5, 1.0 and 2.0 μm) were generated and classified according to the charge by the DMA. Singly charged 0.5 and 1.0 μm particles and doubly charged 2.0 μm particles were used as test particles. The single particle trap system was composed of a light scattering signal detector and a visualization cell. When the particle passed through the detector, trigger signal with a given delay time sent to the solenoid valves upstream and downstream of the visualization cell for trapping the particle in the visualization cell. The motion of particle in the visualization cell was monitored by CCD camera and the gravitational settling velocity and the electrostatic migration velocity were measured from the video image. The aerodynamic diameter obtained from the settling velocity was in good agreement with Stokes diameter calculated from the electrostatic migration velocity for individual particles. It was also found that the aerodynamic diameter obtained from the settling velocity was a one-to-one function of the scattered light intensity of individual particles. The applicability of this system will be discussed.

  8. A prototype system based on visual interactive SDM called VGC

    NASA Astrophysics Data System (ADS)

    Jia, Zelu; Liu, Yaolin; Liu, Yanfang

    2009-10-01

    In many application domains, data is collected and referenced by its geo-spatial location. Spatial data mining, or the discovery of interesting patterns in such databases, is an important capability in the development of database systems. Spatial data mining recently emerges from a number of real applications, such as real-estate marketing, urban planning, weather forecasting, medical image analysis, road traffic accident analysis, etc. It demands for efficient solutions for many new, expensive, and complicated problems. For spatial data mining of large data sets to be effective, it is also important to include humans in the data exploration process and combine their flexibility, creativity, and general knowledge with the enormous storage capacity and computational power of today's computers. Visual spatial data mining applies human visual perception to the exploration of large data sets. Presenting data in an interactive, graphical form often fosters new insights, encouraging the information and validation of new hypotheses to the end of better problem-solving and gaining deeper domain knowledge. In this paper a visual interactive spatial data mining prototype system (visual geo-classify) based on VC++6.0 and MapObject2.0 are designed and developed, the basic algorithms of the spatial data mining is used decision tree and Bayesian networks, and data classify are used training and learning and the integration of the two to realize. The result indicates it's a practical and extensible visual interactive spatial data mining tool.

  9. Visualizing Terrestrial and Aquatic Systems in 3D - in IEEE VisWeek 2014

    EPA Science Inventory

    The need for better visualization tools for environmental science is well documented, and the Visualization for Terrestrial and Aquatic Systems project (VISTAS) aims to both help scientists produce effective environmental science visualizations and to determine which visualizatio...

  10. Automatic Visualization of Software Requirements: Reactive Systems

    SciTech Connect

    Castello, R.; Mili, R.; Tollis, I.G.; Winter, V.

    1999-05-12

    In this paper we present an approach that facilitates the validation of high consequence system requirements. This approach consists of automatically generating a graphical representation from an informal document. Our choice of a graphical notation is statecharts. We proceed in two steps: we first extract a hierarchical decomposition tree from a textual description, then we draw a graph that models the statechart in a hierarchical fashion. The resulting drawing is an effective requirements assessment tool that allows the end user to easily pinpoint inconsistencies and incompleteness.

  11. Face Detection in Complex Visual Displays: An Eye-Tracking Study with 3- and 6-Month-Old Infants and Adults

    ERIC Educational Resources Information Center

    Di Giorgio, Elisa; Turati, Chiara; Altoe, Gianmarco; Simion, Francesca

    2012-01-01

    The ability to detect and prefer a face when embedded in complex visual displays was investigated in 3- and 6-month-old infants, as well as in adults, through a modified version of the visual search paradigm and the recording of eye movements. Participants "(N" = 43) were shown 32 visual displays that comprised a target face among 3 or 5…

  12. Navigation-specific neural coding in the visual system of Drosophila.

    PubMed

    Dewar, Alex D M; Wystrach, Antoine; Graham, Paul; Philippides, Andrew

    2015-10-01

    Drosophila melanogaster are a good system in which to understand the minimal requirements for widespread visually guided behaviours such as navigation, due to their small brains (adults possess only 100,000 neurons) and the availability of neurogenetic techniques which allow the identification of task-specific cell types. Recently published data describe the receptive fields for two classes of visually responsive neurons (R2 and R3/R4d ring neurons in the central complex) that are essential for visual tasks such as orientation memory for salient objects and simple pattern discriminations. What is interesting is that these cells have very large receptive fields and are very small in number, suggesting that each sub-population of cells might be a bottleneck in the processing of visual information for a specific behaviour, as each subset of cells effectively condenses information from approximately 3000 visual receptors in the eye, to fewer than 50 neurons in total. It has recently been shown how R1 ring neurons, which receive input from the same areas as the R2 and R3/R4d cells, are necessary for place learning in Drosophila. However, how R1 neurons enable place learning is unknown. By examining the information provided by different populations of hypothetical visual neurons in simulations of experimental arenas, we show that neurons with ring neuron-like receptive fields are sufficient for defining a location visually. In this way we provide a link between the type of information conveyed by ring neurons and the behaviour they support.

  13. A Dynamic Systems Theory Model of Visual Perception Development

    ERIC Educational Resources Information Center

    Coté, Carol A.

    2015-01-01

    This article presents a model for understanding the development of visual perception from a dynamic systems theory perspective. It contrasts to a hierarchical or reductionist model that is often found in the occupational therapy literature. In this proposed model vision and ocular motor abilities are not foundational to perception, they are seen…

  14. Audio-visual perception system for a humanoid robotic head.

    PubMed

    Viciana-Abad, Raquel; Marfil, Rebeca; Perez-Lorenzo, Jose M; Bandera, Juan P; Romero-Garces, Adrian; Reche-Lopez, Pedro

    2014-05-28

    One of the main issues within the field of social robotics is to endow robots with the ability to direct attention to people with whom they are interacting. Different approaches follow bio-inspired mechanisms, merging audio and visual cues to localize a person using multiple sensors. However, most of these fusion mechanisms have been used in fixed systems, such as those used in video-conference rooms, and thus, they may incur difficulties when constrained to the sensors with which a robot can be equipped. Besides, within the scope of interactive autonomous robots, there is a lack in terms of evaluating the benefits of audio-visual attention mechanisms, compared to only audio or visual approaches, in real scenarios. Most of the tests conducted have been within controlled environments, at short distances and/or with off-line performance measurements. With the goal of demonstrating the benefit of fusing sensory information with a Bayes inference for interactive robotics, this paper presents a system for localizing a person by processing visual and audio data. Moreover, the performance of this system is evaluated and compared via considering the technical limitations of unimodal systems. The experiments show the promise of the proposed approach for the proactive detection and tracking of speakers in a human-robot interactive framework.

  15. Frontoparietal activation during visual conjunction search: Effects of bottom-up guidance and adult age.

    PubMed

    Madden, David J; Parks, Emily L; Tallman, Catherine W; Boylan, Maria A; Hoagey, David A; Cocjin, Sally B; Johnson, Micah A; Chou, Ying-Hui; Potter, Guy G; Chen, Nan-Kuei; Packard, Lauren E; Siciliano, Rachel E; Monge, Zachary A; Diaz, Michele T

    2017-04-01

    We conducted functional magnetic resonance imaging (fMRI) with a visual search paradigm to test the hypothesis that aging is associated with increased frontoparietal involvement in both target detection and bottom-up attentional guidance (featural salience). Participants were 68 healthy adults, distributed continuously across 19 to 78 years of age. Frontoparietal regions of interest (ROIs) were defined from resting-state scans obtained prior to task-related fMRI. The search target was defined by a conjunction of color and orientation. Each display contained one item that was larger than the others (i.e., a size singleton) but was not informative regarding target identity. Analyses of search reaction time (RT) indicated that bottom-up attentional guidance from the size singleton (when coincident with the target) was relatively constant as a function of age. Frontoparietal fMRI activation related to target detection was constant as a function of age, as was the reduction in activation associated with salient targets. However, for individuals 35 years of age and older, engagement of the left frontal eye field (FEF) in bottom-up guidance was more prominent than for younger individuals. Further, the age-related differences in left FEF activation were a consequence of decreasing resting-state functional connectivity in visual sensory regions. These findings indicate that age-related compensatory effects may be expressed in the relation between activation and behavior, rather than in the magnitude of activation, and that relevant changes in the activation-RT relation may begin at a relatively early point in adulthood. Hum Brain Mapp 38:2128-2149, 2017. © 2017 Wiley Periodicals, Inc.

  16. Visual system evolution and the nature of the ancestral snake.

    PubMed

    Simões, B F; Sampaio, F L; Jared, C; Antoniazzi, M M; Loew, E R; Bowmaker, J K; Rodriguez, A; Hart, N S; Hunt, D M; Partridge, J C; Gower, D J

    2015-07-01

    The dominant hypothesis for the evolutionary origin of snakes from 'lizards' (non-snake squamates) is that stem snakes acquired many snake features while passing through a profound burrowing (fossorial) phase. To investigate this, we examined the visual pigments and their encoding opsin genes in a range of squamate reptiles, focusing on fossorial lizards and snakes. We sequenced opsin transcripts isolated from retinal cDNA and used microspectrophotometry to measure directly the spectral absorbance of the photoreceptor visual pigments in a subset of samples. In snakes, but not lizards, dedicated fossoriality (as in Scolecophidia and the alethinophidian Anilius scytale) corresponds with loss of all visual opsins other than RH1 (λmax 490-497 nm); all other snakes (including less dedicated burrowers) also have functional sws1 and lws opsin genes. In contrast, the retinas of all lizards sampled, even highly fossorial amphisbaenians with reduced eyes, express functional lws, sws1, sws2 and rh1 genes, and most also express rh2 (i.e. they express all five of the visual opsin genes present in the ancestral vertebrate). Our evidence of visual pigment complements suggests that the visual system of stem snakes was partly reduced, with two (RH2 and SWS2) of the ancestral vertebrate visual pigments being eliminated, but that this did not extend to the extreme additional loss of SWS1 and LWS that subsequently occurred (probably independently) in highly fossorial extant scolecophidians and A. scytale. We therefore consider it unlikely that the ancestral snake was as fossorial as extant scolecophidians, whether or not the latter are para- or monophyletic.

  17. Time-Gated Optical Projection Tomography Allows Visualization of Adult Zebrafish Internal Structures

    PubMed Central

    Foglia, Efrem Alessandro; Pistocchi, Anna; D'Andrea, Cosimo; Valentini, Gianluca; Cubeddu, Rinaldo; De Silvestri, Sandro; Cerullo, Giulio; Cotelli, Franco

    2012-01-01

    Optical imaging through biological samples is compromised by tissue scattering and currently various approaches aim to overcome this limitation. In this paper we demonstrate that an all optical technique, based on non-linear upconversion of infrared ultrashort laser pulses and on multiple view acquisition, allows the reduction of scattering effects in tomographic imaging. This technique, namely Time-Gated Optical Projection Tomography (TGOPT), is used to reconstruct three dimensionally the internal structure of adult zebrafish without staining or clearing agents. This method extends the use of Optical Projection Tomography to optically diffusive samples yielding reconstructions with reduced artifacts, increased contrast and improved resolution with respect to those obtained with non-gated techniques. The paper shows that TGOPT is particularly suited for imaging the skeletal system and nervous structures of adult zebrafish. PMID:23185643

  18. Visual perception system and method for a humanoid robot

    NASA Technical Reports Server (NTRS)

    Wells, James W. (Inventor); Mc Kay, Neil David (Inventor); Chelian, Suhas E. (Inventor); Linn, Douglas Martin (Inventor); Wampler, II, Charles W. (Inventor); Bridgwater, Lyndon (Inventor)

    2012-01-01

    A robotic system includes a humanoid robot with robotic joints each moveable using an actuator(s), and a distributed controller for controlling the movement of each of the robotic joints. The controller includes a visual perception module (VPM) for visually identifying and tracking an object in the field of view of the robot under threshold lighting conditions. The VPM includes optical devices for collecting an image of the object, a positional extraction device, and a host machine having an algorithm for processing the image and positional information. The algorithm visually identifies and tracks the object, and automatically adapts an exposure time of the optical devices to prevent feature data loss of the image under the threshold lighting conditions. A method of identifying and tracking the object includes collecting the image, extracting positional information of the object, and automatically adapting the exposure time to thereby prevent feature data loss of the image.

  19. A new active visual system for humanoid robots.

    PubMed

    Xu, De; Li, You Fu; Tan, Min; Shen, Yang

    2008-04-01

    In this paper, a new active visual system is developed, which is based on bionic vision and is insensitive to the property of the cameras. The system consists of a mechanical platform and two cameras. The mechanical platform has two degrees of freedom of motion in pitch and yaw, which is equivalent to the neck of a humanoid robot. The cameras are mounted on the platform. The directions of the optical axes of the two cameras can be simultaneously adjusted in opposite directions. With these motions, the object's images can be located at the centers of the image planes of the two cameras. The object's position is determined with the geometry information of the visual system. A more general model for active visual positioning using two cameras without a neck is also investigated. The position of an object can be computed via the active motions. The presented model is less sensitive to the intrinsic parameters of cameras, which promises more flexibility in many applications such as visual tracking with changeable focusing. Experimental results verify the effectiveness of the proposed methods.

  20. Optimal level activity of matrix metalloproteinases is critical for adult visual plasticity in the healthy and stroke-affected brain.

    PubMed

    Pielecka-Fortuna, Justyna; Kalogeraki, Evgenia; Fortuna, Michal G; Löwel, Siegrid

    2015-11-26

    The ability of the adult brain to undergo plastic changes is of particular interest in medicine, especially regarding recovery from injuries or improving learning and cognition. Matrix metalloproteinases (MMPs) have been associated with juvenile experience-dependent primary visual cortex (V1) plasticity, yet little is known about their role in this process in the adult V1. Activation of MMPs is a crucial step facilitating structural changes in a healthy brain; however, upon brain injury, upregulated MMPs promote the spread of a lesion and impair recovery. To clarify these seemingly opposing outcomes of MMP-activation, we examined the effects of MMP-inhibition on experience-induced plasticity in healthy and stoke-affected adult mice. In healthy animals, 7-day application of MMP-inhibitor prevented visual plasticity. Additionally, treatment with MMP-inhibitor once but not twice following stroke rescued plasticity, normally lost under these conditions. Our data imply that an optimal level of MMP-activity is crucial for adult visual plasticity to occur.

  1. Optimal level activity of matrix metalloproteinases is critical for adult visual plasticity in the healthy and stroke-affected brain

    PubMed Central

    Pielecka-Fortuna, Justyna; Kalogeraki, Evgenia; Fortuna, Michal G; Löwel, Siegrid

    2015-01-01

    The ability of the adult brain to undergo plastic changes is of particular interest in medicine, especially regarding recovery from injuries or improving learning and cognition. Matrix metalloproteinases (MMPs) have been associated with juvenile experience-dependent primary visual cortex (V1) plasticity, yet little is known about their role in this process in the adult V1. Activation of MMPs is a crucial step facilitating structural changes in a healthy brain; however, upon brain injury, upregulated MMPs promote the spread of a lesion and impair recovery. To clarify these seemingly opposing outcomes of MMP-activation, we examined the effects of MMP-inhibition on experience-induced plasticity in healthy and stoke-affected adult mice. In healthy animals, 7-day application of MMP-inhibitor prevented visual plasticity. Additionally, treatment with MMP-inhibitor once but not twice following stroke rescued plasticity, normally lost under these conditions. Our data imply that an optimal level of MMP-activity is crucial for adult visual plasticity to occur. DOI: http://dx.doi.org/10.7554/eLife.11290.001 PMID:26609811

  2. Supplement for Adult Service Providers: A Curricular Approach To Support the Transition to Adulthood of Adolescents with Visual or Dual Sensory Impairments and Cognitive Disabilities.

    ERIC Educational Resources Information Center

    O'Neill, John; And Others

    This handbook supplement, for adult service providers, is part of a packet intended to aid educators, families, and adult service providers to facilitate the transition from school to adult life in the community for students with both cognitive disabilities and visual or dual sensory impairments. Emphasis is on preparation of students for adult…

  3. The Effects of Visual Field Conditions on Electromyography of the Lower Extremities during Reaching Tasks in Healthy Adults

    PubMed Central

    Park, Jun Hyuk; Lee, Kyeong Soon; Oh, Tae Young

    2014-01-01

    [Purpose] The purpose of this study was to identify the effects of visual field condition on electromyography of the lower extremities during arm reaching in healthy adults, and to compare differences in electromyography of the lower extremities between young and old adults according to visual fields condition. [Subjects and Methods] Twenty-nine young persons in their 20s and 19 elderly persons in their 60s, a total of 48 persons, participated in this study. Prior to participation in the study, each subject signed an informed consent form to comply with ethics guidelines dictated by the ethics committee for research at Silla University, Korea. We collected the muscle activation data for both of tibialis anterior and gastrocnemius muscle during reaching by subjects using electromyography. Data analysis with SPSS for Window Version 20.0 was performed using repeated one-way analysis of variance according to visual fields and age. [Results] There were no significantly differences between subjects in their 20s and 60s to visual field conditions except for left tibialis anterior muscle activation during left-side reaching. Left tibialis anterior muscle activation in subjects in their 60s was higher than in subjects in their 20s during left-side reaching. [Conclusion] We determined that tibialis anterior muscle activation in subjects in their 60s was higher than in subjects in their 20s. We suggest that visual field conditions are the important factor for physical therapy interventions to improve balance and priority of intervention . PMID:24764630

  4. Visual prosthesis wireless energy transfer system optimal modeling

    PubMed Central

    2014-01-01

    Background Wireless energy transfer system is an effective way to solve the visual prosthesis energy supply problems, theoretical modeling of the system is the prerequisite to do optimal energy transfer system design. Methods On the basis of the ideal model of the wireless energy transfer system, according to visual prosthesis application condition, the system modeling is optimized. During the optimal modeling, taking planar spiral coils as the coupling devices between energy transmitter and receiver, the effect of the parasitic capacitance of the transfer coil is considered, and especially the concept of biological capacitance is proposed to consider the influence of biological tissue on the energy transfer efficiency, resulting in the optimal modeling’s more accuracy for the actual application. Results The simulation data of the optimal model in this paper is compared with that of the previous ideal model, the results show that under high frequency condition, the parasitic capacitance of inductance and biological capacitance considered in the optimal model could have great impact on the wireless energy transfer system. The further comparison with the experimental data verifies the validity and accuracy of the optimal model proposed in this paper. Conclusions The optimal model proposed in this paper has a higher theoretical guiding significance for the wireless energy transfer system’s further research, and provide a more precise model reference for solving the power supply problem in visual prosthesis clinical application. PMID:24428906

  5. Autostereoscopic 3D visualization and image processing system for neurosurgery.

    PubMed

    Meyer, Tobias; Kuß, Julia; Uhlemann, Falk; Wagner, Stefan; Kirsch, Matthias; Sobottka, Stephan B; Steinmeier, Ralf; Schackert, Gabriele; Morgenstern, Ute

    2013-06-01

    A demonstrator system for planning neurosurgical procedures was developed based on commercial hardware and software. The system combines an easy-to-use environment for surgical planning with high-end visualization and the opportunity to analyze data sets for research purposes. The demonstrator system is based on the software AMIRA. Specific algorithms for segmentation, elastic registration, and visualization have been implemented and adapted to the clinical workflow. Modules from AMIRA and the image processing library Insight Segmentation and Registration Toolkit (ITK) can be combined to solve various image processing tasks. Customized modules tailored to specific clinical problems can easily be implemented using the AMIRA application programming interface and a self-developed framework for ITK filters. Visualization is done via autostereoscopic displays, which provide a 3D impression without viewing aids. A Spaceball device allows a comfortable, intuitive way of navigation in the data sets. Via an interface to a neurosurgical navigation system, the demonstrator system can be used intraoperatively. The precision, applicability, and benefit of the demonstrator system for planning of neurosurgical interventions and for neurosurgical research were successfully evaluated by neurosurgeons using phantom and patient data sets.

  6. Soldier-worn augmented reality system for tactical icon visualization

    NASA Astrophysics Data System (ADS)

    Roberts, David; Menozzi, Alberico; Clipp, Brian; Russler, Patrick; Cook, James; Karl, Robert; Wenger, Eric; Church, William; Mauger, Jennifer; Volpe, Chris; Argenta, Chris; Wille, Mark; Snarski, Stephen; Sherrill, Todd; Lupo, Jasper; Hobson, Ross; Frahm, Jan-Michael; Heinly, Jared

    2012-06-01

    This paper describes the development and demonstration of a soldier-worn augmented reality system testbed that provides intuitive 'heads-up' visualization of tactically-relevant geo-registered icons. Our system combines a robust soldier pose estimation capability with a helmet mounted see-through display to accurately overlay geo-registered iconography (i.e., navigation waypoints, blue forces, aircraft) on the soldier's view of reality. Applied Research Associates (ARA), in partnership with BAE Systems and the University of North Carolina - Chapel Hill (UNC-CH), has developed this testbed system in Phase 2 of the DARPA ULTRA-Vis (Urban Leader Tactical, Response, Awareness, and Visualization) program. The ULTRA-Vis testbed system functions in unprepared outdoor environments and is robust to numerous magnetic disturbances. We achieve accurate and robust pose estimation through fusion of inertial, magnetic, GPS, and computer vision data acquired from helmet kit sensors. Icons are rendered on a high-brightness, 40°×30° field of view see-through display. The system incorporates an information management engine to convert CoT (Cursor-on-Target) external data feeds into mil-standard icons for visualization. The user interface provides intuitive information display to support soldier navigation and situational awareness of mission-critical tactical information.

  7. Seeing your way to health: the visual pedagogy of Bess Mensendieck's physical culture system.

    PubMed

    Veder, Robin

    2011-01-01

    This essay examines the images and looking practices central to Bess M. Mensendieck's (c.1866-1959) 'functional exercise' system, as documented in physical culture treatises published in Germany and the United States between 1906 and 1937. Believing that muscular realignment could not occur without seeing how the body worked, Mensendieck taught adult non-athletes to see skeletal alignment and muscular movement in their own and others' bodies. Three levels of looking practices are examined: didactic sequences; penetrating inspection and appreciation of physiological structures; and ideokinetic visual metaphors for guiding movement. With these techniques, Mensendieck's work bridged the body cultures of German Nacktkultur (nudism), American labour efficiency and the emerging physical education profession. This case study demonstrates how sport historians could expand their analyses to include practices of looking as well as questions of visual representation.

  8. Big Data Visual Analytics for Exploratory Earth System Simulation Analysis

    SciTech Connect

    Steed, Chad A.; Ricciuto, Daniel M.; Shipman, Galen M.; Smith, Brian E.; Thornton, Peter E.; Wang, Dali; Shi, Xiaoying; Williams, Dean N.

    2013-12-01

    Rapid increases in high performance computing are feeding the development of larger and more complex data sets in climate research, which sets the stage for so-called big data analysis challenges. However, conventional climate analysis techniques are inadequate in dealing with the complexities of today s data. In this paper, we describe and demonstrate a visual analytics system, called the Exploratory Data analysis ENvironment (EDEN), with specific application to the analysis of complex earth system simulation data sets. EDEN represents the type of interactive visual analysis tools that are necessary to transform data into insight, thereby improving critical comprehension of earth system processes. In addition to providing an overview of EDEN, we describe real-world studies using both point ensembles and global Community Land Model Version 4 (CLM4) simulations.

  9. An Indoor Navigation System for the Visually Impaired

    PubMed Central

    Guerrero, Luis A.; Vasquez, Francisco; Ochoa, Sergio F.

    2012-01-01

    Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user's trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment. PMID:22969398

  10. An indoor navigation system for the visually impaired.

    PubMed

    Guerrero, Luis A; Vasquez, Francisco; Ochoa, Sergio F

    2012-01-01

    Navigation in indoor environments is highly challenging for the severely visually impaired, particularly in spaces visited for the first time. Several solutions have been proposed to deal with this challenge. Although some of them have shown to be useful in real scenarios, they involve an important deployment effort or use artifacts that are not natural for blind users. This paper presents an indoor navigation system that was designed taking into consideration usability as the quality requirement to be maximized. This solution enables one to identify the position of a person and calculates the velocity and direction of his movements. Using this information, the system determines the user's trajectory, locates possible obstacles in that route, and offers navigation information to the user. The solution has been evaluated using two experimental scenarios. Although the results are still not enough to provide strong conclusions, they indicate that the system is suitable to guide visually impaired people through an unknown built environment.

  11. Visualization in aerospace research with a large wall display system

    NASA Astrophysics Data System (ADS)

    Matsuo, Yuichi

    2002-05-01

    National Aerospace Laboratory of Japan has built a large- scale visualization system with a large wall-type display. The system has been operational since April 2001 and comprises a 4.6x1.5-meter (15x5-foot) rear projection screen with 3 BARCO 812 high-resolution CRT projectors. The reason we adopted the 3-gun CRT projectors is support for stereoscopic viewing, ease with color/luminosity matching and accuracy of edge-blending. The system is driven by a new SGI Onyx 3400 server of distributed shared-memory architecture with 32 CPUs, 64Gbytes memory, 1.5TBytes FC RAID disk and 6 IR3 graphics pipelines. Software is another important issue for us to make full use of the system. We have introduced some applications available in a multi- projector environment such as AVS/MPE, EnSight Gold and COVISE, and been developing some software tools that create volumetric images with using SGI graphics libraries. The system is mainly used for visualization fo computational fluid dynamics (CFD) simulation sin aerospace research. Visualized CFD results are of our help for designing an improved configuration of aerospace vehicles and analyzing their aerodynamic performances. These days we also use it for various collaborations among researchers.

  12. Attention to Quantitative and Configural Properties of Abstract Visual Patterns by Children and Adults.

    ERIC Educational Resources Information Center

    Mendelson, Morton J.

    1984-01-01

    Students in grades two, four, six, and college sorted abstract visual patterns that varied both in amount of contour and in type of visual organization (unstructured, simple symmetries, multiple symmetries, and rotational). Results suggested that children attend to both amount of contour and visual organization, but that attention to visual…

  13. Visualization and Classification of Power System Frequency Data Streams

    SciTech Connect

    Bank, Jason N; Omitaomu, Olufemi A; Fernandez, Steven J; Liu, Yilu

    2009-01-01

    Two challenges in the realization of the smart grid technology are the ability to visualize the deluge of expected data streams for global situational awareness and the ability to detect disruptive and classify events from spatially-distributed high-speed power system frequency measurements while minimizing false alarms and eliminating missed detection. This paper presents an interactive visualization model for high speed power system frequency data streams that presents both local and global views of the data streams for decision making process. It also presents a K-Median for clustering and identifying disruptive events in spatially-distributed data streams. The results from experimental evaluation on a variety of datasets show that K-Median achieve better performance and empowers analysts with the ability to make sense of a deluge of frequency measurements in a real-time situation.

  14. Environmental information system for visualizing environmental impact assessment information.

    PubMed

    Cserny, Angelika; Kovács, Zsófia; Domokos, Endre; Rédey, Akos

    2009-01-01

    The Institute of Environmental Engineering at the University of Pannonia has undertaken the challenge to develop an online environmental information system. This system is able to receive and process the collected environmental data via Internet. The authors have attached importance to the presentation of the data and have included other comprehensible information for laymen as well in order to work out visualisation techniques that are expressive and attract attention for environmental questions through the developed information system. The ways of visualizing physical and chemical parameters of surface water and the effects of motorway construction were examined.

  15. Simulation and visualization of mechanical systems in immersive virtual environments

    SciTech Connect

    Canfield, T. R.

    1998-04-17

    A prototype for doing real-time simulation of mechanical systems in immersive virtual environments has been developed to run in the CAVE and on the ImmersaDesk at Argonne National Laboratory. This system has three principal software components: a visualization component for rendering the model and providing a user interface, communications software, and mechanics simulation software. The system can display the three-dimensional objects in the CAVE and project various scalar fields onto the exterior surface of the objects during real-time execution.

  16. The role of gravitation-dependent systems in visual tracking.

    PubMed

    Kornilova, L N

    2004-10-01

    The effects of prolonged microgravity conditions on the performance of visual tracking functions such as fixational rotations of the eyes (saccades), smooth tracking of linear and curved movements of a foveal point stimulus, and following a vertical pendulum-like movement of foveoretinal optokinetic stimuli were studied. Experiments were performed on 31 cosmonauts in freefall conditions, in ten cases followed by additional studies after a cycle of head movements and in 14 after resting. These experiments showed that while intrinsic visual functions were retained in microgravity conditions, there were decreases in the precision and speed measures of all types of visual tracking (fixational rotations of the eyes, smooth tracking) and, in some cases, complete degradation of the smooth tracking reflex, an increase in the time taken to fix the gaze on a target (by factors of 2 or more), and decreases in the frequency of stimulus tracking. During the initial period of adaptation to the altered gravitational conditions and periodically during prolonged flight, the system of smooth visual tracking was found to undergo a transition to a strategy of saccadic approximation, in which gaze tracks the movement of the target using a set of macro- or microsaccadic movements. These impairments, seen in virtually all the cosmonauts, resulted from vestibular deprivation (functional deafferentation of the otolith input) in conditions of weightlessness, while in cosmonauts conceptualizing space on the basis of perceiving the positions of the feet and head additionally showed support-tactile deprivation.

  17. Visualizing failure effects in complex human-machine systems

    NASA Astrophysics Data System (ADS)

    Price, Jana M.; Mathur, Amit; Morley, Rebecca M.; Scalzo, Richard C.

    2001-07-01

    The ability to understand a system's behavior in both normal and failed conditions is fundamental to the design of error-tolerant systems as well as to the development of diagnostics. The System Analysis for Failure and Error Reduction (SAFER) Project seeks to provide designers with tools to visualize potential sources of error and their effects early in the design of human-machine systems. The project is based on an existing technology that provides a failure-space modeling environment, analysis capabilities for troubleshooting, and error diagnostics using design data of machine systems. The SAFER Project extends the functionality of the existing technology in two significant ways. First, by adding a model of human error probability within the tool, designers are able to estimate the probabilities of human errors and the effects that these errors may have on system components and on the entire system. Second, the visual presentation of failure-related measures and metrics has been improved through a process of user-centered design. This paper will describe the process that was used to develop the human error probability model and will present novel metrics for assessing failure within complex systems.

  18. Intelligent Data Visualization for Cross-Checking Spacecraft System Diagnosis

    NASA Technical Reports Server (NTRS)

    Ong, James C.; Remolina, Emilio; Breeden, David; Stroozas, Brett A.; Mohammed, John L.

    2012-01-01

    Any reasoning system is fallible, so crew members and flight controllers must be able to cross-check automated diagnoses of spacecraft or habitat problems by considering alternate diagnoses and analyzing related evidence. Cross-checking improves diagnostic accuracy because people can apply information processing heuristics, pattern recognition techniques, and reasoning methods that the automated diagnostic system may not possess. Over time, cross-checking also enables crew members to become comfortable with how the diagnostic reasoning system performs, so the system can earn the crew s trust. We developed intelligent data visualization software that helps users cross-check automated diagnoses of system faults more effectively. The user interface displays scrollable arrays of timelines and time-series graphs, which are tightly integrated with an interactive, color-coded system schematic to show important spatial-temporal data patterns. Signal processing and rule-based diagnostic reasoning automatically identify alternate hypotheses and data patterns that support or rebut the original and alternate diagnoses. A color-coded matrix display summarizes the supporting or rebutting evidence for each diagnosis, and a drill-down capability enables crew members to quickly view graphs and timelines of the underlying data. This system demonstrates that modest amounts of diagnostic reasoning, combined with interactive, information-dense data visualizations, can accelerate system diagnosis and cross-checking.

  19. Advanced 3D Sensing and Visualization System for Unattended Monitoring

    SciTech Connect

    Carlson, J.J.; Little, C.Q.; Nelson, C.L.

    1999-01-01

    The purpose of this project was to create a reliable, 3D sensing and visualization system for unattended monitoring. The system provides benefits for several of Sandia's initiatives including nonproliferation, treaty verification, national security and critical infrastructure surety. The robust qualities of the system make it suitable for both interior and exterior monitoring applications. The 3D sensing system combines two existing sensor technologies in a new way to continuously maintain accurate 3D models of both static and dynamic components of monitored areas (e.g., portions of buildings, roads, and secured perimeters in addition to real-time estimates of the shape, location, and motion of humans and moving objects). A key strength of this system is the ability to monitor simultaneous activities on a continuous basis, such as several humans working independently within a controlled workspace, while also detecting unauthorized entry into the workspace. Data from the sensing system is used to identi~ activities or conditions that can signi~ potential surety (safety, security, and reliability) threats. The system could alert a security operator of potential threats or could be used to cue other detection, inspection or warning systems. An interactive, Web-based, 3D visualization capability was also developed using the Virtual Reality Modeling Language (VRML). The intex%ace allows remote, interactive inspection of a monitored area (via the Internet or Satellite Links) using a 3D computer model of the area that is rendered from actual sensor data.

  20. Designing visual displays and system models for safe reactor operations

    SciTech Connect

    Brown-VanHoozer, S.A.

    1995-12-31

    The material presented in this paper is based on two studies involving the design of visual displays and the user`s prospective model of a system. The studies involve a methodology known as Neuro-Linguistic Programming and its use in expanding design choices from the operator`s perspective image. The contents of this paper focuses on the studies and how they are applicable to the safety of operating reactors.

  1. `Flight of colours' in lesions of the visual system 1

    PubMed Central

    Feldman, Martin; Todman, Leo; Bender, Morris B.

    1974-01-01

    A bright pocket flashlight was directed into one eye for 10 seconds; the subject then closed the eyelids and reported the sequence of after-image colours observed. Lesions of the visual system which compromised bilateral central colour vision also reduced or abolished the `flight of colours'. This simple bedside test of each eye independently is of value in detecting mild defects of central vision. PMID:4457619

  2. Windows into the Visual Brain: New Discoveries about the Visual System, Its Functions, and Implications for Practitioners

    ERIC Educational Resources Information Center

    Jan, James E.; Heaven, Roberta K. B.; Matsuba, Carey; Langley, M. Beth; Roman-Lantzy, Christine; Anthony, Tanni L

    2013-01-01

    Introduction: In recent years, major progress has been made in understanding the human visual system because of new investigative techniques. These developments often contradict older concepts about visual function. Methods: A detailed literature search and interprofessional discussions. Results: Recent innovative neurological tests are described…

  3. Visual Cortex Plasticity Following Peripheral Damage To The Visual System: fMRI Evidence.

    PubMed

    Lemos, João; Pereira, Daniela; Castelo-Branco, Miguel

    2016-10-01

    Over the last two decades, functional magnetic resonance imaging (fMRI) has become a powerful research method to investigate cortical visual plasticity. Abnormal fMRI response patterns have been occasionally detected in the visually deprived cortex of patients with bilateral retinal diseases. Controversy remains whether these observations indicate structural reorganization of the visual cortex or unmasking of previously silent cortico-cortical connections. In optic nerve diseases, there is weak evidence showing that early visual cortex seems to lack reorganization, while higher-order visual areas undergo plastic changes which may contribute to optimise visual function. There is however accumulating imaging evidence demonstrating trans-synaptic degeneration of the visual cortex in patients with disease of the anterior visual pathways. This may preclude the use of restorative treatments in these patients. Here, we review and update the body of fMRI evidence on visual cortical plasticity.

  4. A computer graphics system for visualizing spacecraft in orbit

    NASA Technical Reports Server (NTRS)

    Eyles, Don E.

    1989-01-01

    To carry out unanticipated operations with resources already in space is part of the rationale for a permanently manned space station in Earth orbit. The astronauts aboard a space station will require an on-board, spatial display tool to assist the planning and rehearsal of upcoming operations. Such a tool can also help astronauts to monitor and control such operations as they occur, especially in cases where first-hand visibility is not possible. A computer graphics visualization system designed for such an application and currently implemented as part of a ground-based simulation is described. The visualization system presents to the user the spatial information available in the spacecraft's computers by drawing a dynamic picture containing the planet Earth, the Sun, a star field, and up to two spacecraft. The point of view within the picture can be controlled by the user to obtain a number of specific visualization functions. The elements of the display, the methods used to control the display's point of view, and some of the ways in which the system can be used are described.

  5. Visualization and exploration for recommender systems in enterprise organization

    NASA Astrophysics Data System (ADS)

    Karni, Z.; Shapira, L.

    2013-03-01

    Recommender systems seek to predict the interest a user would find in an item, person or social element they had not yet considered, based upon the properties of the item, the user's past experience and similar users. However, recommended items are often presented to the user with no context and no ability to influence the results. We present a novel visualization technique for recommender systems in which, a user can see the items recommended for him, and understand why they were recommended. Focusing on a user, we render a planar visualization listing a set of recommended items. The items are organized such that similar items reside nearby on the screen, centered around realtime generated categories. We use a combination of iconography, text and tag clouds, with maximal use of screen real estate, and keep items from overlapping to produce our results. We apply our visualization to expert relevance maps in the enterprise and a book recommendation system for consumers. The latter is based on Shelfari, a social network for reading and books.

  6. Illustrative volume visualization using GPU-based particle systems.

    PubMed

    van Pelt, Roy; Vilanova, Anna; van de Wetering, Huub

    2010-01-01

    Illustrative techniques are generally applied to produce stylized renderings. Various illustrative styles have been applied to volumetric data sets, producing clearer images and effectively conveying visual information. We adopt particle systems to produce user-configurable stylized renderings from the volume data, imitating traditional pen-and-ink drawings. In the following, we present an interactive GPU-based illustrative volume rendering framework, called VolFliesGPU. In this framework, isosurfaces are sampled by evenly distributed particle sets, delineating surface shape by illustrative styles. The appearance of these styles is based on locally-measured surface properties. For instance, hatches convey surface shape by orientation and shape characteristics are enhanced by color, mapped using a curvature-based transfer function. Hidden-surfaces are generally removed to avoid visual clutter, after that a combination of styles is applied per isosurface. Multiple surfaces and styles can be explored interactively, exploiting parallelism in both graphics hardware and particle systems. We achieve real-time interaction and prompt parametrization of the illustrative styles, using an intuitive GPGPU paradigm that delivers the computational power to drive our particle system and visualization algorithms.

  7. Plasticity in adult cat visual cortex (area 17) following circumscribed monocular lesions of all retinal layers

    PubMed Central

    Calford, M B; Wang, C; Taglianetti, V; Waleszczyk, W J; Burke, W; Dreher, B

    2000-01-01

    In eight adult cats intense, sharply circumscribed, monocular laser lesions were used to remove all cellular layers of the retina. The extents of the retinal lesions were subsequently confirmed with counts of α-ganglion cells in retinal whole mounts; in some cases these revealed radial segmental degeneration of ganglion cells distal to the lesion.Two to 24 weeks later, area 17 (striate cortex; V1) was studied electrophysiologically in a standard anaesthetized, paralysed (artificially respired) preparation. Recording single- or multineurone activity revealed extensive topographical reorganization within the lesion projection zone (LPZ).Thus, with stimulation of the lesioned eye, about 75 % of single neurones in the LPZ had ‘ectopic’ visual discharge fields which were displaced to normal retina in the immediate vicinity of the lesion.The sizes of the ectopic discharge fields were not significantly different from the sizes of the normal discharge fields. Furthermore, binocular cells recorded from the LPZ, when stimulated via their ectopic receptive fields, exhibited orientation tuning and preferred stimulus velocities which were indistinguishable from those found when the cells were stimulated via the normal eye.However, the responses to stimuli presented via ectopic discharge fields were generally weaker (lower peak discharge rates) than those to presentations via normal discharge fields, and were characterized by a lower-than-normal upper velocity limit.Overall, the properties of the ectopic receptive fields indicate that cortical mechanisms rather than a retinal ‘periphery’ effect underlie the topographic reorganization of area 17 following monocular retinal lesions. PMID:10767137

  8. Visual Simulation of Microalgae Growth in Bioregenerative Life Support System

    NASA Astrophysics Data System (ADS)

    Zhao, Ming

    Bioregenerative life support system is one of the key technologies for future human deep space exploration and long-term space missions. BLSS use biological system as its core unit in combination with other physical and chemical equipments, under the proper control and manipulation by crew to complete a specific task to support life. Food production, waste treatment, oxygen and water regeneration are all conducted by higher plants or microalgae in BLSS, which is the most import characteristic different from other kinds of life support systems. Microalgae is light autotrophic micro-organisms, light undoubtedly is the most import factor which limits its growth and reproduction. Increasing or decreasing the light intensity changes the growth rate of microalgae, and then regulates the concentration of oxygen and carbon dioxide in the system. In this paper, based on the mathematical model of microalgae which grew under the different light intensity, three-dimensional visualization model was built and realized through using 3ds max, Virtools and some other three dimensional software, in order to display its change and impacting on oxygen and carbon dioxide intuitively. We changed its model structure and parameters, such as establishing closed-loop control system, light intensity, temperature and Nutrient fluid’s velocity and so on, carried out computer virtual simulation, and observed dynamic change of system with the aim of providing visualization support for system research.

  9. Estimating the relative weights of visual and auditory tau versus heuristic-based cues for time-to-contact judgments in realistic, familiar scenes by older and younger adults.

    PubMed

    Keshavarz, Behrang; Campos, Jennifer L; DeLucia, Patricia R; Oberfeld, Daniel

    2017-04-01

    Estimating time to contact (TTC) involves multiple sensory systems, including vision and audition. Previous findings suggested that the ratio of an object's instantaneous optical size/sound intensity to its instantaneous rate of change in optical size/sound intensity (τ) drives TTC judgments. Other evidence has shown that heuristic-based cues are used, including final optical size or final sound pressure level. Most previous studies have used decontextualized and unfamiliar stimuli (e.g., geometric shapes on a blank background). Here we evaluated TTC estimates by using a traffic scene with an approaching vehicle to evaluate the weights of visual and auditory TTC cues under more realistic conditions. Younger (18-39 years) and older (65+ years) participants made TTC estimates in three sensory conditions: visual-only, auditory-only, and audio-visual. Stimuli were presented within an immersive virtual-reality environment, and cue weights were calculated for both visual cues (e.g., visual τ, final optical size) and auditory cues (e.g., auditory τ, final sound pressure level). The results demonstrated the use of visual τ as well as heuristic cues in the visual-only condition. TTC estimates in the auditory-only condition, however, were primarily based on an auditory heuristic cue (final sound pressure level), rather than on auditory τ. In the audio-visual condition, the visual cues dominated overall, with the highest weight being assigned to visual τ by younger adults, and a more equal weighting of visual τ and heuristic cues in older adults. Overall, better characterizing the effects of combined sensory inputs, stimulus characteristics, and age on the cues used to estimate TTC will provide important insights into how these factors may affect everyday behavior.

  10. The effect of visual field condition on kinetic in upper extremities and e.m.g in lower extremities while performing reaching in normal adults

    PubMed Central

    Park, Hyekang; Kang, Youngeun; Yoo, Minah; Lee, Bomjin; Yang, Jeongok; Lee, Joongsook; Han, Dongwook; Oh, Taeyoung

    2017-01-01

    [Purpose] The aims of this study was to investigate mean velocity and angle of shoulder joint, activation of tibialis anterior and gastrocnemius according to both eyes, dominant eye and non-dominant eye condition during reaching task in normal adults. [Subjects and Methods] Our research recruited 24 participants (male 11, female 13) in Silla University. Participants were performed reaching out movement by conditions of both eye, dominants eye, non-dominants eye. The target was placed at 45 degree diagonal direction and distance far away 130% of their arm length. Kinetic analysis of the upper extremities was investigated by QUALISYS 3-dimensional motion analysis system. Muscle activation were measured by EMG during reaching tasks. The collected data were statistically processed using the SPSS for win version 20.0. [Results] There was a significant difference of shoulder joint velocity of flexion, abduction and internal rotation according to visual field condition during reaching tasks. There was no significant difference of shoulder joint angle and muscle activation according to visual field conditions during reaching tasks. [Conclusion] In conclusion, visual field has an influence on shoulder joint velocity. Therefore, the visual field may be to play an important role in reach performance. PMID:28210047

  11. Individual differences in involvement of the visual object recognition system during visual word recognition.

    PubMed

    Laszlo, Sarah; Sacchi, Elizabeth

    2015-01-01

    Individuals with dyslexia often evince reduced activation during reading in left hemisphere (LH) language regions. This can be observed along with increased activation in the right hemisphere (RH), especially in areas associated with object recognition - a pattern referred to as RH compensation. The mechanisms of RH compensation are relatively unclear. We hypothesize that RH compensation occurs when the RH object recognition system is called upon to supplement an underperforming LH visual word form recognition system. We tested this by collecting ERPs while participants with a range of reading abilities viewed words, objects, and word/object ambiguous items (e.g., "SMILE" shaped like a smile). Less experienced readers differentiate words, objects, and ambiguous items less strongly, especially over the RH. We suggest that this lack of differentiation may have negative consequences for dyslexic individuals demonstrating RH compensation.

  12. Auditory and visual stream segregation in children and adults: an assessment of the amodality assumption of the 'sluggish attentional shifting' theory of dyslexia.

    PubMed

    Lallier, Marie; Thierry, Guillaume; Tainturier, Marie-Josèphe; Donnadieu, Sophie; Peyrin, Carole; Billard, Catherine; Valdois, Sylviane

    2009-12-11

    Among the hypotheses relating dyslexia to a temporal processing disorder, Hari and Renvall (Hari, R., Renvall, H., 2001. Impaired processing of rapid stimulus sequences in dyslexia. Trends. Cognit. Sci. 5, 525-532.) argued that dyslexic individuals would show difficulties at an attentional level, through sluggish attentional shifting (SAS) in all sensory modalities. However, the amodality assumption of the SAS theory was never straightforwardly assessed in the same group of dyslexic participants using similar paradigms in both the visual and auditory modalities. Here, the attentional sequential performance of control and dyslexic participants was evaluated using rapid serial presentation paradigms measuring individual stream segregation thresholds in the two modalities. The first experiment conducted on French dyslexic children with a phonological disorder revealed an SAS only in the auditory modality only which was strongly related to reading performance. The second experiment carried out on British dyslexic young adults with a phonological disorder using the same auditory segregation task but a different visual paradigm revealed an SAS in both the visual and the auditory modalities. In addition, a relationship was found in this group between SAS, poor reading and poor phonological skills. Two further control experiments showed that differences in task design or participants' language between Experiments 1 and 2 could not account for the differences in terms of visual segregation patterns. Overall, our results support the view that the auditory SAS plays a role in developmental dyslexia via its impact on phonological abilities. In addition, a visual temporal disorder in dyslexia might emerge at a later developmental stage, when the visual system normally becomes more expert at rapid temporal processing.

  13. The Use of Audio-Visual Media for the Education of Adults.

    ERIC Educational Resources Information Center

    Mathur, J. C.

    1978-01-01

    An Indian adult educator discusses the value of "pleasure-oriented" audiovisual adult education, the use of both commercial and subsidized films, television, and radio for their educational potential. He notes several production needs and techniques. (MF)

  14. Dynamic Visualization of Co-expression in Systems Genetics Data

    SciTech Connect

    New, Joshua Ryan; Huang, Jian; Chesler, Elissa J

    2008-01-01

    Biologists hope to address grand scientific challenges by exploring the abundance of data made available through modern microarray technology and other high-throughput techniques. The impact of this data, however, is limited unless researchers can effectively assimilate such complex information and integrate it into their daily research; interactive visualization tools are called for to support the effort. Specifically, typical studies of gene co-expression require novel visualization tools that enable the dynamic formulation and fine-tuning of hypotheses to aid the process of evaluating sensitivity of key parameters. These tools should allow biologists to develop an intuitive understanding of the structure of biological networks and discover genes which reside in critical positions in networks and pathways. By using a graph as a universal data representation of correlation in gene expression data, our novel visualization tool employs several techniques that when used in an integrated manner provide innovative analytical capabilities. Our tool for interacting with gene co-expression data integrates techniques such as: graph layout, qualitative subgraph extraction through a novel 2D user interface, quantitative subgraph extraction using graph-theoretic algorithms or by querying an optimized b-tree, dynamic level-of-detail graph abstraction, and template-based fuzzy classification using neural networks. We demonstrate our system using a real-world workflow from a large-scale, systems genetics study of mammalian gene co-expression.

  15. Lighting System for Visual Perception Enhancement in Volume Rendering.

    PubMed

    Wang, Lei; Kaufman, Arie E

    2013-01-01

    We introduce a lighting system that enhances the visual cues in a rendered image for the perception of 3D volumetric objects. We divide the lighting effects into global and local effects, and deploy three types of directional lights: the key light and accessory lights (fill and detail lights). The key light provides both lighting effects and carries the visual cues for the perception of local and global shapes and depth. The cues for local shapes are conveyed by gradient; those for global shapes are carried by shadows; and those for depth are provided by shadows and translucent objects. Fill lights produce global effects to increase the perceptibility. Detail lights generate local effects to improve the cues for local shapes. Our method quantifies the perception and uses an exhaustive search to set the lights. It configures accessory lights with the consideration of preserving the global impression conveyed by the key light. It ensures the feeling of smooth light movements in animations. With simplification, it achieves interactive frame rates and produces results that are visually indistinguishable from results using the nonsimplified algorithm. The major contributions of this paper are our lighting system, perception measurement and lighting design algorithm with our indistinguishable simplification.

  16. Normal Visual Acuity and Electrophysiological Contrast Gain in Adults with High-Functioning Autism Spectrum Disorder

    PubMed Central

    Tebartz van Elst, Ludger; Bach, Michael; Blessing, Julia; Riedel, Andreas; Bubl, Emanuel

    2015-01-01

    A common neurodevelopmental disorder, autism spectrum disorder (ASD), is defined by specific patterns in social perception, social competence, communication, highly circumscribed interests, and a strong subjective need for behavioral routines. Furthermore, distinctive features of visual perception, such as markedly reduced eye contact and a tendency to focus more on small, visual items than on holistic perception, have long been recognized as typical ASD characteristics. Recent debate in the scientific community discusses whether the physiology of low-level visual perception might explain such higher visual abnormalities. While reports of this enhanced, “eagle-like” visual acuity contained methodological errors and could not be substantiated, several authors have reported alterations in even earlier stages of visual processing, such as contrast perception and motion perception at the occipital cortex level. Therefore, in this project, we have investigated the electrophysiology of very early visual processing by analyzing the pattern electroretinogram-based contrast gain, the background noise amplitude, and the psychophysical visual acuities of participants with high-functioning ASD and controls with equal education. Based on earlier findings, we hypothesized that alterations in early vision would be present in ASD participants. This study included 33 individuals with ASD (11 female) and 33 control individuals (12 female). The groups were matched in terms of age, gender, and education level. We found no evidence of altered electrophysiological retinal contrast processing or psychophysical measured visual acuities. There appears to be no evidence for abnormalities in retinal visual processing in ASD patients, at least with respect to contrast detection. PMID:26379525

  17. Design principles of insect and vertebrate visual systems.

    PubMed

    Sanes, Joshua R; Zipursky, S Lawrence

    2010-04-15

    A century ago, Cajal noted striking similarities between the neural circuits that underlie vision in vertebrates and flies. Over the past few decades, structural and functional studies have provided strong support for Cajal's view. In parallel, genetic studies have revealed some common molecular mechanisms controlling development of vertebrate and fly visual systems and suggested that they share a common evolutionary origin. Here, we review these shared features, focusing on the first several layers-retina, optic tectum (superior colliculus), and lateral geniculate nucleus in vertebrates; and retina, lamina, and medulla in fly. We argue that vertebrate and fly visual circuits utilize common design principles and that taking advantage of this phylogenetic conservation will speed progress in elucidating both functional strategies and developmental mechanisms, as has already occurred in other areas of neurobiology ranging from electrical signaling and synaptic plasticity to neurogenesis and axon guidance.

  18. DESIGN PRINCIPLES OF INSECT AND VERTEBRATE VISUAL SYSTEMS

    PubMed Central

    Sanes, Joshua R.; Zipursky, S. Lawrence

    2010-01-01

    A century ago, Cajal noted striking similarities between the neural circuits that underlie vision in vertebrates and flies. Over the past few decades, structural and functional studies have provided strong support for Cajal’s view. In parallel, genetic studies have revealed some common molecular mechanisms controlling development of vertebrate and fly visual systems and suggested that they share a common evolutionary origin. Here, we review these shared features, focusing on the first several layers - retina, optic tectum (superior colliculus) and lateral geniculate nucleus in vertebrates, and retina, lamina and medulla in fly. We argue that vertebrate and fly visual circuits utilize common design principles, and that taking advantage of this phylogenetic conservation will speed progress in elucidating both functional strategies and developmental mechanisms, as has already occurred in other areas of neurobiology ranging from electrical signaling and synaptic plasticity to neurogenesis and axon guidance. PMID:20399726

  19. An interactive, discipline-independent data visualization system

    NASA Technical Reports Server (NTRS)

    Treinish, Lloyd A.

    1989-01-01

    The data visualization techniques used by National Space Science Data Center Graphics System are discussed. The system includes a self-describing data abstraction for the storage and manipulation of multidimensional data for discipline-independent scientific applications. The system's data format and graphics display are described. Consideration is given to techniques developed for the rapid display and manipulation of large, complex data sets and for manipulating algorithms with portable implementations which can operate on any data object or geometry. The processes of operating the system are given and examples are presented from applying the system to various types of data, including TOMS data, data from the International Satellite Cloud Climatology Project, and IRAS data.

  20. Dual task performance in older adults: Examining visual discrimination performance whilst treadmill walking at preferred and non-preferred speeds.

    PubMed

    Duncan, Michael J; Smith, Mike; Clarke, Neil D; Eyre, Emma L J; Wright, Sheila Leddington

    2016-04-01

    This study examined visual discrimination performance in a sample of older adults before, during and post treadmill walking at preferred walking speed and preferred walking speed +20%. Nine adults (6 females and 3 males) aged 60-77 years (mean age=67.1±5.7 years) undertook three trials each lasting 15 min, rest, walking at preferred speed and walking at preferred speed +20%. Pre, during and post each condition, participants undertook measures of visual-cognitive performance. There were no significant main effects or higher order interactions for condition (rest, vs. walking preferred speed, vs. walking preferred speed +20%) or time (pre, during, post) (all P>0.05). There was a significant condition X time interaction for response time (P=0.014, partial ɳ(2)=0.352). Post hoc analysis indicated that response times were significantly faster during exercise at preferred speed compared to pre exercise at preferred speed (P=0.042). Response times were significantly slower during walking at preferred speed +20% compared to pre exercise (P=0.002) and to post exercise (P=0.012). Response times were significantly faster during PSW compared to during rest (P=0.05), during PSW compared to during PSW20 (P=0.001) and significantly slower during PSW20 compared to during rest (P=0.001). Post PSW20 response times were significantly slower than post PSW (P=0.04). These results suggest that visual discrimination performance is facilitated when walking at preferred speeds but walking at 20% faster than preferred speed significantly impedes visual discrimination in older adults.

  1. Transformation of the Adult Education System in Slovakia

    NASA Astrophysics Data System (ADS)

    Švec, Štefan

    1998-07-01

    This article examines trends in adult education in Slovakia since it became a separate republic in 1993. Economic and social transformations during this period have led to a re-thinking of the adult education system. The author describes four basic modalities for providing adult education in Slovakia: (1) schools and colleges; (2) cultural centres and similar institutions; (3) institutions for vocational training; (4) voluntary organizations such as trade unions, political parties and ethnic minority groups.

  2. Changes in Retinal Morphology, Electroretinogram and Visual Behavior after Transient Global Ischemia in Adult Rats

    PubMed Central

    Zhao, Ying; Yu, Bo; Xiang, Yong-Hui; Han, Xin-Jia; Xu, Ying; So, Kwok-Fai; Xu, An-Ding; Ruan, Yi-Wen

    2013-01-01

    The retina is a light-sensitive tissue of the central nervous system that is vulnerable to ischemia. The pathological mechanism underlying retinal ischemic injury is not fully understood. The purpose of this study was to investigate structural and functional changes of different types of rat retinal neurons and visual behavior following transient global ischemia. Retinal ischemia was induced using a 4-vessel occlusion model. Compared with the normal group, the number of βIII-tubulin positive retinal ganglion cells and calretinin positive amacrine cells were reduced from 6 h to 48 h following ischemia. The number of recoverin positive cone bipolar cells transiently decreased at 6 h and 12 h after ischemia. However, the fluorescence intensity of rhodopsin positive rod cells and fluorescent peanut agglutinin positive cone cells did not change after reperfusion. An electroretinogram recording showed that the a-wave, b-wave, oscillatory potentials and the photopic negative response were completely lost during ischemia. The amplitudes of the a- and b-waves were partially recovered at 1 h after ischemia, and returned to the control level at 48 h after reperfusion. However, the amplitudes of oscillatory potentials and the photopic negative response were still reduced at 48 h following reperfusion. Visual behavior detection showed there was no significant change in the time spent in the dark chamber between the control and 48 h group, but the distance moved, mean velocity in the black and white chambers and intercompartmental crosses were reduced at 48 h after ischemia. These results indicate that transient global ischemia induces dysfunction of retinal ganglion cells and amacrine cells at molecular and ERG levels. However, transient global ischemia in a 17 minute duration does not appear to affect photoreceptors. PMID:23776500

  3. Cross-Language Modulation of Visual Attention Span: An Arabic-French-Spanish Comparison in Skilled Adult Readers

    PubMed Central

    Awadh, Faris H. R.; Phénix, Thierry; Antzaka, Alexia; Lallier, Marie; Carreiras, Manuel; Valdois, Sylviane

    2016-01-01

    In delineating the amount of orthographic information that can be processed in parallel during a single fixation, the visual attention (VA) span acts as a key component of the reading system. Previous studies focused on the contribution of VA span to normal and pathological reading in monolingual and bilingual children from different European languages, without direct cross-language comparison. In the current paper, we explored modulations of VA span abilities in three languages –French, Spanish, and Arabic– that differ in transparency, reading direction and writing systems. The participants were skilled adult readers who were native speakers of French, Spanish or Arabic. They were administered tasks of global and partial letter report, single letter identification and text reading. Their VA span abilities were assessed using tasks that require the processing of briefly presented five consonant strings (e.g., R S H F T). All five consonants had to be reported in global report but a single cued letter in partial report. Results showed that VA span was reduced in Arabic readers as compared to French or Spanish readers who otherwise show a similar high performance in the two report tasks. The analysis of VA span response patterns in global report showed a left-right asymmetry in all three languages. A leftward letter advantage was found in French and Spanish but a rightward advantage in Arabic. The response patterns were symmetric in partial report, regardless of the language. Last, a significant relationship was found between VA span abilities and reading speed but only for French. The overall findings suggest that the size of VA span, the shape of VA span response patterns and the VA Span-reading relationship are modulated by language-specific features. PMID:27014125

  4. Ontogenetic adaptations in the visual systems of deep-sea crustaceans.

    PubMed

    Frank, Tamara M

    2017-04-05

    For all visually competent organisms, the driving force behind the adaptation of photoreceptors involves obtaining the best balance of resolution to sensitivity in the prevailing light regime, as an increase in sensitivity often results in a decrease in resolution. A number of marine species have an additional problem to deal with, in that the juvenile stages live in relatively brightly lit shallow (100-200 m depth) waters, whereas the adult stages have daytime depths of more than 600 m, where little downwelling light remains. Here, I present the results of electrophysiological analyses of the temporal resolution and irradiance sensitivity of juvenile and adult stages of two species of ontogenetically migrating crustaceans (Gnathophausia ingens and Systellaspis debilis) that must deal with dramatically different light environments and temperatures during their life histories. The results demonstrate that there are significant effects of temperature on temporal resolution, which help to optimize the visual systems of the two life-history stages for their respective light environments.This article is part of the themed issue 'Vision in dim light'.

  5. Scientific Visualization & Modeling for Earth Systems Science Education

    NASA Technical Reports Server (NTRS)

    Chaudhury, S. Raj; Rodriguez, Waldo J.

    2003-01-01

    Providing research experiences for undergraduate students in Earth Systems Science (ESS) poses several challenges at smaller academic institutions that might lack dedicated resources for this area of study. This paper describes the development of an innovative model that involves students with majors in diverse scientific disciplines in authentic ESS research. In studying global climate change, experts typically use scientific visualization techniques applied to remote sensing data collected by satellites. In particular, many problems related to environmental phenomena can be quantitatively addressed by investigations based on datasets related to the scientific endeavours such as the Earth Radiation Budget Experiment (ERBE). Working with data products stored at NASA's Distributed Active Archive Centers, visualization software specifically designed for students and an advanced, immersive Virtual Reality (VR) environment, students engage in guided research projects during a structured 6-week summer program. Over the 5-year span, this program has afforded the opportunity for students majoring in biology, chemistry, mathematics, computer science, physics, engineering and science education to work collaboratively in teams on research projects that emphasize the use of scientific visualization in studying the environment. Recently, a hands-on component has been added through science student partnerships with school-teachers in data collection and reporting for the GLOBE Program (GLobal Observations to Benefit the Environment).

  6. Encoding of configural regularity in the human visual system.

    PubMed

    Kubilius, Jonas; Wagemans, Johan; Op de Beeck, Hans P

    2014-08-13

    The visual system is very efficient in encoding stimulus properties by utilizing available regularities in the inputs. To explore the underlying encoding strategies during visual information processing, we presented participants with two-line configurations that varied in the amount of configural regularity (or degrees of freedom in the relative positioning of the two lines) in a fMRI experiment. Configural regularity ranged from a generic configuration to stimuli resembling an "L" (i.e., a right-angle L-junction), a "T" (i.e., a right-angle midpoint T-junction), or a "+",-the latter being the most regular stimulus. We found that the response strength in the shape-selective lateral occipital area was consistently lower for a higher degree of regularity in the stimuli. In the second experiment, using multivoxel pattern analysis, we further show that regularity is encoded in terms of the fMRI signal strength but not in the distributed pattern of responses. Finally, we found that the results of these experiments could not be accounted for by low-level stimulus properties and are distinct from norm-based encoding. Our results suggest that regularity plays an important role in stimulus encoding in the ventral visual processing stream.

  7. ARM-based visual processing system for prosthetic vision.

    PubMed

    Matteucci, Paul B; Byrnes-Preston, Philip; Chen, Spencer C; Lovell, Nigel H; Suaning, Gregg J

    2011-01-01

    A growing number of prosthetic devices have been shown to provide visual perception to the profoundly blind through electrical neural stimulation. These first-generation devices offer promising outcomes to those affected by degenerative disorders such as retinitis pigmentosa. Although prosthetic approaches vary in their placement of the stimulating array (visual cortex, optic-nerve, epi-retinal surface, sub-retinal surface, supra-choroidal space, etc.), most of the solutions incorporate an externally-worn device to acquire and process video to provide the implant with instructions on how to deliver electrical stimulation to the patient, in order to elicit phosphenized vision. With the significant increase in availability and performance of low power-consumption smart phone and personal device processors, the authors investigated the use of a commercially available ARM (Advanced RISC Machine) device as an externally-worn processing unit for a prosthetic neural stimulator for the retina. A 400 MHz Samsung S3C2440A ARM920T single-board computer was programmed to extract 98 values from a 1.3 Megapixel OV9650 CMOS camera using impulse, regional averaging and Gaussian sampling algorithms. Power consumption and speed of video processing were compared to results obtained to similar reported devices. The results show that by using code optimization, the system is capable of driving a 98 channel implantable device for the restoration of visual percepts to the blind.

  8. Head Worn Display System for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Cupero, Frank; Valimont, Brian; Wise, John; Best. Carl; DeMers, Bob

    2009-01-01

    Head-Worn Displays or so-called, near-to-eye displays have potentially significant advantages in terms of cost, overcoming cockpit space constraints, and for the display of spatially-integrated information. However, many technical issues need to be overcome before these technologies can be successfully introduced into commercial aircraft cockpits. The results of three activities are reported. First, the near-to-eye display design, technological, and human factors issues are described and a literature review is presented. Second, the results of a fixed-base piloted simulation, investigating the impact of near to eye displays on both operational and visual performance is reported. Straight-in approaches were flown in simulated visual and instrument conditions while using either a biocular or a monocular display placed on either the dominant or non-dominant eye. The pilot's flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested. The data generally supports a monocular design with minimal impact due to eye dominance. Finally, a method for head tracker system latency measurement is developed and used to compare two different devices.

  9. Visualizing nursing workforce distribution: policy evaluation using geographic information systems.

    PubMed

    Courtney, Karen L

    2005-12-01

    Health services literature suggests that geographic information systems (GIS) are useful policy evaluation tools when policy success is dependent on location. Nursing workforce distribution is an inherently local issue and nursing shortages present serious concerns for local, state and national governments. In 1991, Missouri enacted a nurse recruitment and retention policy targeting underserved (HPSA-designated) counties. Following Institutional Review Board approval, policy effectiveness was explored using a combination of GIS data visualization, spatial and classic statistics. Results of both data visualization and statistical methods do not demonstrate an expected trend of decreasing group differences between HPSA and non-HPSA-designated counties over time. Only two of the five time periods studied had significant group differences. Between 1993 and 1995, the loss in nurse to population ratios in HPSA counties was significant (U=1020, p<0.001); however, between 1999 and 2001, the growth in nurse to population ratio changes in HPSA counties was significant (U=1032, p=0.001). The GIS data visualization and statistical techniques performed suggest that current policy definitions of underserved areas may not be effective in defining areas of nursing shortages and the existing policy implementation may not be achieving the stated goals.

  10. New data visualization of the LHC Era Monitoring (Lemon) system

    NASA Astrophysics Data System (ADS)

    Ivan, Fedorko; Veronique, Lefebure; Daniel, Lenkes; Omar, Pera Mira

    2012-12-01

    In the last few years, new requirements have been received for visualization of monitoring data: advanced graphics, flexibility in configuration and decoupling of the presentation layer from the monitoring repository. Lemonweb is the data visualization component of the LHC Era Monitoring (Lemon) system. Lemonweb consists of two subcomponents: a data collector and a web visualization interface. The data collector is a daemon, implemented in Python, responsible for data gathering from the central monitoring repository and storing into time series data structures. Data is stored on disk in Round Robin Database (RRD) files: one file per monitored entity, with set of entity related metrics. Entities may be grouped into a hierarchical structure, called “clusters” and supporting mathematical operations over entities and clusters (e.g. cluster A + cluster B /clusters C - entity XY). Using the configuration information, a cluster definition is evaluated in the collector engine and, at runtime, a sequence of data selects is built, to optimize access to the central monitoring repository. In this article, an overview of the design and architecture as well as highlights of some implemented features will be presented.

  11. Visual and Vestibular Induced Eye Movements in Verbal Children and Adults with Autism.

    PubMed

    Furman, Joseph M; Osorio, Maria J; Minshew, Nancy J

    2015-12-01

    This study assessed the functionality of vestibular, pursuit, and saccade circuitry in autism across a wide age range. Subjects were 79 individuals with autism (AUT) and 62 controls (CON) aged 5 to 52 years with IQ scores > 70. For vestibular testing, earth-vertical axis rotation was performed in darkness and in a lighted visual surround with a fixation target. Ocular motor testing included assessment of horizontal saccades and horizontal smooth pursuit. No between-group differences were found in vestibular reflexes or in mean saccade velocity or accuracy. Saccade latency was increased in the AUT group with significant age-related effects in the 8-18 year old subgroups. There was a trend toward decreased pursuit gain without age effects. Normal vestibular-induced eye movements and normal saccade accuracy and velocity provide the most substantial evidence to date of the functional integrity of brainstem and cerebellar pathways in autism, suggesting that the histopathological abnormalities described in these structures may not be associated with intrinsic dysfunction but rather reflect developmental alterations related to forebrain cortical systems formation. Increased saccade latency with age effects adds to the extensive existing evidence of altered function and maturation of cortical systems in autism.

  12. Live Interrogation and Visualization of Earth Systems (LIVES)

    NASA Astrophysics Data System (ADS)

    Nunn, J. A.; Anderson, L. C.

    2007-12-01

    Twenty tablet PCs and associated peripherals acquired through a HP Technology for Teaching grant are being used to redesign two freshman laboratory courses as well as a sophomore geobiology course in Geology and Geophysics at Louisiana State University. The two introductory laboratories serve approximately 750 students per academic year including both majors and non-majors; the geobiology course enrolls about 35 students/year and is required for majors in the department's geology concentration. Limited enrollments and 3 hour labs make it possible to incorporate hands-on visualization, animation, GIS, manipulation of data and images, and access to geological data available online. Goals of the course redesigns include: enhancing visualization of earth materials, physical/chemical/biological processes, and biosphere/geosphere history; strengthening student's ability to acquire, manage, and interpret multifaceted geological information; fostering critical thinking, the scientific method, and earth-system science/perspective in ancient and modern environments (such as coastal erosion and restoration in Louisiana or the Snowball Earth hypothesis); improving student communication skills; and increasing the quantity, quality, and diversity of students pursuing Earth Science careers. IT resources available in the laboratory provide students with sophisticated visualization tools, allowing them to switch between 2-D and 3-D reconstructions more seamlessly, and enabling them to manipulate larger integrated data- sets, thus permitting more time for critical thinking and hypothesis testing. IT resources also enable faculty and students to simultaneously work with simulation software to animate earth processes such as plate motions or groundwater flow and immediately test hypothesis formulated in the data analysis. Finally, tablet PCs make it possible for data gathering and analysis outside a formal classroom. As a result, students will achieve fluency in using visualization

  13. Information processing in the primate visual system - An integrated systems perspective

    NASA Technical Reports Server (NTRS)

    Van Essen, David C.; Anderson, Charles H.; Felleman, Daniel J.

    1992-01-01

    The primate visual system contains dozens of distinct areas in the cerebral cortex and several major subcortical structures. These subdivisions are extensively interconnected in a distributed hierarchical network that contains several intertwined processing streams. A number of strategies are used for efficient information processing within this hierarchy. These include linear and nonlinear filtering, passage through information bottlenecks, and coordinated use of multiple types of information. In addition, dynamic regulation of information flow within and between visual areas may provide the computational flexibility needed for the visual system to perform a broad spectrum of tasks accurately and at high resolution.

  14. Adult age differences in the functional neuroanatomy of visual attention: A combined fMRI and DTI study

    PubMed Central

    Madden, David J.; Spaniol, Julia; Whiting, Wythe L.; Bucur, Barbara; Provenzale, James M.; Cabeza, Roberto; White, Leonard E.; Huettel, Scott A.

    2007-01-01

    We combined measures from event-related functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and cognitive performance (visual search response time) to test the hypotheses that differences between younger and older adults in top-down (goal-directed) attention would be related to cortical activation, and that white matter integrity as measured by DTI (fractional anisotropy, FA) would be a mediator of this age-related effect. Activation in frontal and parietal cortical regions was overall greater for older adults than for younger adults. The relation between activation and search performance supported the hypothesis of age differences in top-down attention. When the task involved top-down control (increased target predictability), performance was associated with frontoparietal activation for older adults, but with occipital (fusiform) activation for younger adults. White matter integrity (FA) exhibited an age-related decline that was more pronounced for anterior brain regions than for posterior regions, but white matter integrity did not specifically mediate the age-related increase in activation of the frontoparietal attentional network. PMID:16500004

  15. Recognition of Facially Expressed Emotions and Visual Search Strategies in Adults with Asperger Syndrome

    ERIC Educational Resources Information Center

    Falkmer, Marita; Bjallmark, Anna; Larsson, Matilda; Falkmer, Torbjorn

    2011-01-01

    Can the disadvantages persons with Asperger syndrome frequently experience with reading facially expressed emotions be attributed to a different visual perception, affecting their scanning patterns? Visual search strategies, particularly regarding the importance of information from the eye area, and the ability to recognise facially expressed…

  16. A Quantitative Analysis of the Work Experiences of Adults with Visual Impairments in Nigeria

    ERIC Educational Resources Information Center

    Wolffe, Karen E.; Ajuwon, Paul M.; Kelly, Stacy M.

    2013-01-01

    Introduction: Worldwide, people with visual impairments often struggle to gain employment. This study attempts to closely evaluate the work experiences of employed individuals with visual impairments living in one of the world's most populous developing nations, Nigeria. Methods: The researchers developed a questionnaire that assessed personal and…

  17. The Analysis of Adult Immigrants' Learning System in Canada

    ERIC Educational Resources Information Center

    Mukan, Nataliya; Barabash, Olena; Busko, Maria

    2015-01-01

    In the article the problem of adult immigrants' learning in Canada has been studied. The main objectives of the article are defined as: analysis of scientific and pedagogical literature which highlights different aspects of the research problem; analysis of the adult immigrants' learning system in Canada; and the perspectives for creative…

  18. Comparing Adult Learning Systems: An Emerging Political Economy

    ERIC Educational Resources Information Center

    Rees, Gareth

    2013-01-01

    Adult learning systems have come to be dominated by the view that the essential role of adult learning is to generate the high levels of skills deemed necessary for competitiveness and growth in the globalised economy. This 'education gospel' is underpinned by human capital theory (HCT) and its contemporary conceptualisation in terms of…

  19. Systemic vascular function is associated with muscular power in adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-associated loss of muscular strength and muscular power are critical determinants of loss of physical function and progression to disability in older adults. In this study, we examined the association of systemic vascular function and measures of muscle strength and power in older adults. Measu...

  20. Cognitive robotic system for learning of complex visual stimuli

    NASA Astrophysics Data System (ADS)

    Potapov, A. S.; Rozhkov, A. S.

    2013-05-01

    The problem of learning of complex visual stimuli in cognitive robotics is considered. These stimuli should be selected on the base of rules supporting arbitrary comparisons of stimulus features with features of other salient objects (context). New perceptual knowledge representation based on the predicate logic is implemented to express such rules. Computable predicates are provided by low-level vision system. The rules are constructed using genetic algorithms on the base of a set of examples obtained by a robot during consequent trials. Dependence between the number of necessary trials and rule complexity is studied.

  1. Diurnality, nocturnality, and the evolution of primate visual systems.

    PubMed

    Ankel-Simons, F; Rasmussen, D T

    2008-01-01

    Much of the recent research on the evolution of primate visual systems has assumed that a minimum number of shifts have occurred in circadian activity patterns over the course of primate evolution. The evolutionary origins of key higher taxonomic groups have been interpreted by some researchers as a consequence of a rare shift from nocturnality to diurnality (e.g., Anthropoidea) or from diurnality to nocturnality (e.g., Tarsiidae). Interpreting the evolution of primate visual systems with an ecological approach without parsimony constraints suggests that the evolutionary transitions in activity pattern are more common than what would be allowed by parsimony models, and that such transitions are probably less important in the origin of higher level taxa. The analysis of 17 communities of primates distributed widely around the world and through geological time shows that primate communities consistently contain both nocturnal and diurnal forms, regardless of the taxonomic sources of the communities. This suggests that primates in a community will adapt their circadian pattern to fill empty diurnal or nocturnal niches. Several evolutionary transitions from one pattern to the other within narrow taxonomic groups are solidly documented, and these cases probably represent a small fraction of such transitions throughout the Cenozoic. One or more switches have been documented among platyrrhine monkeys, Malagasy prosimians, Eocene omomyids, Eocene adapoids, and early African anthropoids, with inconclusive but suggestive data within tarsiids. The interpretation of living and extinct primates as fitting into one of two diarhythmic categories is itself problematic, because many extant primates show significant behavioral activity both nocturnally and diurnally. Parsimony models routinely interpret ancestral primates to have been nocturnal, but analyses of morphological and genetic data indicate that they may have been diurnal, or that early primate radiations were likely to

  2. Eddy Current System for Material Inspection and Flaw Visualization

    NASA Technical Reports Server (NTRS)

    Bachnak, R.; King, S.; Maeger, W.; Nguyen, T.

    2007-01-01

    Eddy current methods have been successfully used in a variety of non-destructive evaluation applications including detection of cracks, measurements of material thickness, determining metal thinning due to corrosion, measurements of coating thickness, determining electrical conductivity, identification of materials, and detection of corrosion in heat exchanger tubes. This paper describes the development of an eddy current prototype that combines positional and eddy-current data to produce a C-scan of tested material. The preliminary system consists of an eddy current probe, a position tracking mechanism, and basic data visualization capability. Initial test results of the prototype are presented in this paper.

  3. Assessment of visual space recognition in patients with visual field defects using head mounted display (HMD) system: case study with severe visual field defect.

    PubMed

    Sugihara, Shunichi; Tanaka, Toshiaki; Miyasaka, Tomoya; Izumi, Takashi; Shimizu, Koichi

    2013-01-01

    For the quantitative assessment of visual field defects of cerebrovascular patients, we developed a new measurement system that could present various kinds of visual information to the patient. In this system, we use a head mounted display as the display device. The quantitative assessment becomes possible by adding the capability to measure the eye movement and the head movement simultaneously by means of a video apparatus of motion analysis. In our study, we examined the effectiveness of this system by applying it to a patient with serious visual field defects. The visual image of the reduced test paper was presented to the patient, the effect on his/her spatial recognition and eye movement was investigated. The results indicated the increase in the ration of visual search in the reduced side. With the reduced image, the decrease of the angular velocity of eye movement was recognized in the visual search in the defected side. In the motion analysis, the head movement was not observed while the eye movements appeared corresponding to each different conditions. This fact led us to confirm that the patient coped with this kind of test by the eye movement. In this analysis, the effectiveness and the usefulness of the developed system were confirmed that enables us to evaluate the abnormal and compensation movement of the eyes.

  4. Engineering a visual system for seeing through fog

    NASA Technical Reports Server (NTRS)

    Larimer, J.; Pavel, M.; Ahumada, A.; Sweet, B.

    1992-01-01

    We examine the requirements for on-board aircraft sensor systems that would allow pilots to 'see through' poor weather, especially fog, and land and rollout aircraft under conditions that currently cause flight cancellations and airport closures. Three visual aspects of landing and rollout are distinguished: guidance, hazard detection and hazard recognition. The visual features which support the tasks are discussed. Three broad categories of sensor technology are examined: passive millimeter wave (PMMW), imaging radar, and passive infrared (IR). PMMW and imaging radar exhibit good weather penetration, but poor spatial and temporal resolution. Imaging radar exhibits good weather penetration, but typically relies on a flat-earth assumption which can lead to interpretive errors. PMMW systems have a narrow field of view. IR has poorer weather penetration but good spatial resolution. We recommend using both millimeter-wave and infrared sensor systems, blending the images using multiresolution digital-image pyramid-processing technology, and fusing the resulting real-time images with stored database imagery of the same scene.

  5. Dynamic visualization of coexpression in systems genetics data.

    PubMed

    New, Joshua; Kendall, Wesley; Huang, Jian; Chesler, Elissa

    2008-01-01

    Biologists hope to address grand scientific challenges by exploring the abundance of data made available through modern microarray technology and other high-throughput techniques. The impact of this data, however, is limited unless researchers can effectively assimilate such complex information and integrate it into their daily research; interactive visualization tools are called for to support the effort. Specifically, typical studies of gene co-expression require novel visualization tools that enable the dynamic formulation and fine-tuning of hypotheses to aid the process of evaluating sensitivity of key parameters. These tools should allow biologists to develop an intuitive understanding of the structure of biological networks and discover genes residing in critical positions in networks and pathways. By using a graph as a universal representation of correlation in gene expression, our system employs several techniques that when used in an integrated manner provide innovative analytical capabilities. Our tool for interacting with gene co-expression data integrates techniques such as: graph layout, qualitative subgraph extraction through a novel 2D user interface, quantitative subgraph extraction using graph-theoretic algorithms or by compound queries, dynamic level-of-detail abstraction, and template-based fuzzy classification. We demonstrate our system using a real-world workflow from a large-scale, systems genetics study of mammalian gene co-expression.

  6. Executive Function Is Necessary for Perspective Selection, Not Level-1 Visual Perspective Calculation: Evidence from a Dual-Task Study of Adults

    ERIC Educational Resources Information Center

    Qureshi, Adam W.; Apperly, Ian A.; Samson, Dana

    2010-01-01

    Previous research suggests that perspective-taking and other "theory of mind" processes may be cognitively demanding for adult participants, and may be disrupted by concurrent performance of a secondary task. In the current study, a Level-1 visual perspective task was administered to 32 adults using a dual-task paradigm in which the secondary task…

  7. Environmental fog/rain visual display system for aircraft simulators

    NASA Technical Reports Server (NTRS)

    Chase, W. D. (Inventor)

    1982-01-01

    An environmental fog/rain visual display system for aircraft simulators is described. The electronic elements of the system include a real time digital computer, a caligraphic color display which simulates landing lights of selective intensity, and a color television camera for producing a moving color display of the airport runway as depicted on a model terrain board. The mechanical simulation elements of the system include an environmental chamber which can produce natural fog, nonhomogeneous fog, rain and fog combined, or rain only. A pilot looking through the aircraft wind screen will look through the fog and/or rain generated in the environmental chamber onto a viewing screen with the simulated color image of the airport runway thereon, and observe a very real simulation of actual conditions of a runway as it would appear through actual fog and/or rain.

  8. 14 CFR 1221.108 - Establishment of the NASA Unified Visual Communications System.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Establishment of the NASA Unified Visual... Insignia, NASA Logotype, NASA Program Identifiers, NASA Flags, and the Agency's Unified Visual Communications System § 1221.108 Establishment of the NASA Unified Visual Communications System. (a) The...

  9. SAVS: A Space and Atmospheric Visualization Science system

    NASA Technical Reports Server (NTRS)

    Szuszczewicz, E. P.; Mankofsky, A.; Blanchard, P.; Goodrich, C.; McNabb, D.; Kamins, D.

    1995-01-01

    The research environment faced by space and atmospheric scientists in the 1990s is characterized by unprecedented volumes of new data, by ever-increasing repositories of unexploited mission files, and by the widespread use of empirical and large-scale computational models needed for the synthesis of understanding across data sets and discipline boundaries. The effective analysis and interpretation of such massive amounts of information have become the subjects of legitimate concern. With SAVS (a Space and Atmospheric Visualization Science System), we address these issues by creating a 'push-button' software environment that mimics the logical scientific processes in data acquisition, reduction, and analysis without requiring a detailed understanding of the methods, networks, and modules that link the tools and effectively execute the functions. SAVS provides (1) a customizable framework for accessing a powerful set of visualization tools based on the popular AVS visualization software with hooks to PV-Wave and access to Khoros modules, (2) a set of mathematical and statistical tools, (3) an extensible library of discipline-specific functions and models (e.g., MSIS, IRI, Feldstein Oval, IGRF, satellite tracking with CADRE-3, etc.), and (4) capabilities for local and remote data base access. The system treats scalar, vector, and image data, and runs on most common Unix workstations. We present a description of SAVS and its components, followed by several applications based on generic research interests in interplanetary and magnetospheric physics (IMP/ISTP), active experiments in space (CRRES), and mission planning focused on the Earth's thermospheric, ionospheric, and mesospheric domains (TIMED).

  10. Body mass index, pain score and Alvarado score are useful predictors of appendix visualization at ultrasound in adults.

    PubMed

    Kaewlai, Rathachai; Lertlumsakulsub, Waraporn; Srichareon, Pungkava

    2015-06-01

    The study objective was to find factors predictive of ultrasound visualization of the appendix in patients with suspected appendicitis. A total of 238 consecutive adult patients (178 women, mean age 38.9 y, weight 58.2 kg, body mass index 22.7) who underwent appendiceal ultrasound from January to December 2011 were included. Appendicitis was confirmed in 171 patients (171/238, 71.9%). Ultrasound sensitivity, specificity and accuracy were 64%, 90% and 71%, respectively. The appendix was visualized at ultrasound in 126 patients (group 1) and not visualized in 112 patients (group 2). Group 1 had a lower body mass index, higher pain score and higher Alvarado score. The chances of visualizing the appendix in patients with body mass indexes ≤22, pain scores ≥6, and Alvarado scores ≥6 were 2.3, 2.9, and 3.8 times higher than those of their counterparts, respectively. Therefore, in patients with these factors, the use of ultrasound may be beneficial in the diagnosis of acute appendicitis.

  11. Visual performance and ocular abnormalities in deaf children and young adults: a literature review.

    PubMed

    Hollingsworth, Richard; Ludlow, Amanda K; Wilkins, Arnold; Calver, Richard; Allen, Peter M

    2014-06-01

    Visual defects are common in deaf individuals. Refractive error and ocular motor abnormalities are frequently reported, with hyperopia, myopia, astigmatism and anomalies of binocular vision, all showing a greater prevalence in deaf individuals compared with the general population. Near visual function in deaf individuals has been relatively neglected in the literature to date. Comparisons between studies are problematic due to differences in methodology and population characteristics. Any untreated visual defect has the potential to impair the development of language, with consequences for education more generally, and there is a need to improve screening and treatments of deaf children.

  12. METHODS FOR MONITORING THE EFFECTS OF ENVIRONMENTAL TOXINS ON THE VISUAL SYSTEM.

    EPA Science Inventory

    A high percentage of neurotoxic compounds adversely effect the visual system. Our goal is to apply the tools of vision science to problems of toxicological import, exposure-related alterations in visual physiology, psychophysical function, and ocular development. Methods can ...

  13. Exposure to electronic nicotine delivery systems (ENDS) visual imagery increases smoking urge and desire.

    PubMed

    King, Andrea C; Smith, Lia J; Fridberg, Daniel J; Matthews, Alicia K; McNamara, Patrick J; Cao, Dingcai

    2016-02-01

    Use and awareness of electronic nicotine delivery systems (ENDS; also known as electronic cigarettes or e-cigarettes) has increased rapidly in recent years, particularly among young adults. As use of ENDS resembles traditional smoking in both hand-to-mouth movements and inhalation and exhalation behaviors, we determined whether exposure to e-cigarette use via video exposure would act as a cue to elicit urge and desire for a combustible cigarette. Young adult smokers (mean age of 26.3 ± 4.1 years) were randomized to view a brief video montage of advertisements depicting either e-cigarette vaping (n = 38) or bottled water drinking (n = 40). Pre- and postcue exposure assessments were conducted in a controlled laboratory setting without other smoking or vaping cues present or behaviors allowed. Primary outcomes included change from pre-exposure baseline in smoking urge (Brief Questionnaire of Smoking Urges) and desire for a combustible and e-cigarette (visual analogue scales). Results showed that relative to exposure to the bottled water video, exposure to the ENDS video significantly increased smoking urge (p < .001) as well as desire for a regular cigarette (p < .05) and an e-cigarette (p < .001). These findings provide preliminary evidence that passive exposure to video imagery of ENDS use may generalize as a condition cue and evoke urges for a combustible cigarette in young adult smokers. It remains to be determined whether such increases in urge and desire correspond to increases in actual smoking behavior.

  14. Visualization Component of Vehicle Health Decision Support System

    NASA Technical Reports Server (NTRS)

    Jacob, Joseph; Turmon, Michael; Stough, Timothy; Siegel, Herbert; Walter, patrick; Kurt, Cindy

    2008-01-01

    The visualization front-end of a Decision Support System (DSS) also includes an analysis engine linked to vehicle telemetry, and a database of learned models for known behaviors. Because the display is graphical rather than text-based, the summarization it provides has a greater information density on one screen for evaluation by a flight controller.This tool provides a system-level visualization of the state of a vehicle, and drill-down capability for more details and interfaces to separate analysis algorithms and sensor data streams. The system-level view is a 3D rendering of the vehicle, with sensors represented as icons, tied to appropriate positions within the vehicle body and colored to indicate sensor state (e.g., normal, warning, anomalous state, etc.). The sensor data is received via an Information Sharing Protocol (ISP) client that connects to an external server for real-time telemetry. Users can interactively pan, zoom, and rotate this 3D view, as well as select sensors for a detail plot of the associated time series data. Subsets of the plotted data can be selected and sent to an external analysis engine to either search for a similar time series in an historical database, or to detect anomalous events. The system overview and plotting capabilities are completely general in that they can be applied to any vehicle instrumented with a collection of sensors. This visualization component can interface with the ISP for data streams used by NASA s Mission Control Center at Johnson Space Center. In addition, it can connect to, and display results from, separate analysis engine components that identify anomalies or that search for past instances of similar behavior. This software supports NASA's Software, Intelligent Systems, and Modeling element in the Exploration Systems Research and Technology Program by augmenting the capability of human flight controllers to make correct decisions, thus increasing safety and reliability. It was designed specifically as a

  15. Monocular Deprivation in Adult Mice Alters Visual Acuity and Single-Unit Activity

    ERIC Educational Resources Information Center

    Evans, Scott; Lickey, Marvin E.; Pham, Tony A.; Fischer, Quentin S.; Graves, Aundrea

    2007-01-01

    It has been discovered recently that monocular deprivation in young adult mice induces ocular dominance plasticity (ODP). This contradicts the traditional belief that ODP is restricted to a juvenile critical period. However, questions remain. ODP of young adults has been observed only using methods that are indirectly related to vision, and the…

  16. Visual inspection system with flexible illumination and autofocusing

    NASA Astrophysics Data System (ADS)

    Roh, Young Jun; Lee, Duk-Young; Kim, Min-Young; Cho, Hyungsuck

    2002-10-01

    The visual information obtained from CCD camera is vulnerable to external illumination and the surface reflection properties of object images. Thus, the success of extracting aimed features from images depends mostly on the appropriate design of illumination. This paper presents a visual inspection system that is equipped with a flexible illumination and an auto-focusing unit. The proposed illumination system consists of a three-layered LED illumination device and the controllable diffusers. Each layer is composed of LEDs arranged in a ring type, and a controllable diffuser unit is located in front of each layer. The diffuser plays a role of diffusing lights emitted from the LEDs so that the characteristics of illumination is made varied. This combined configuration of the LED light sources and the adjustable diffuser creates the various lighting conditions. In addition to this flexible illumination function, the vision system is equipped with an auto-focusing unit composed of a pattern projector and a working distance adjustable zoom camera. For the auto-focusing, hill climbing algorithm is used here based on a reliable focus measure that is defined as the variance of high frequency terms in an image. Through a series of experiments, the influence of the illumination system on image quality is analyzed for various objects that have different reflective properties and shapes. As an example study, the electrical parts inspection is investigated. In this study, several types of chips with different sizes and heights are segmented and focused automatically, and then analyzed for part inspection. The results obtained from a series of experiments confirm the usefulness of the proposed system and the effectiveness of the illumination and focusing method.

  17. The Lung Surfactant System in Adult Respiratory Distress Syndrome.

    DTIC Science & Technology

    1979-12-01

    TITLE (and Subtitle) S. TYPE OF REPORT & PERIOD COVERo THE LUNG SURFACTANT SYSTEM IN ADULT RESPIRATORY Annual DISTRESS SYNDROME 6. PERFORMING ORO. REPORT...SURFACTANT SYSTEM IN ADULT RESPIRATORY DISTRESS SYNDROME - Annual Progress Report John U. Balis December 1979 Sponsored by: US ARMY MEDICAL RESEARCH AND...112-116, 1979. 6. Hallman, M., Feldman, B.H., Kirkpatrick, E. and Gluck, L.: Absence of phosphatidylglycerol (PG) in respiratory distress syndrome in

  18. A visual-analytics system for railway safety management.

    PubMed

    Lira, Wallace P; Alves, Ronnie; Costa, Jean M R; Pessin, Gustavo; Galvao, Lilyan; Cardoso, Ana C; de Souza, Cleidson R B

    2014-01-01

    The working environment of railways is challenging and complex and often involves high-risk operations. These operations affect both the company staff and inhabitants of the towns and cities alongside the railway lines. To reduce the employees' and public's exposure to risk, railway companies adopt strategies involving trained safety personnel, advanced forms of technology, and special work processes. Nevertheless, unfortunate incidents still occur. To assist railway safety management, researchers developed a visual-analytics system. Using a data analytics workflow, it compiles an incident risk index that processes information about railway incidents. It displays the index on a geographical map, together with socioeconomic information about the associated towns and cities. Feedback on this system suggests that safety engineers and experts can use it to make and communicate decisions.

  19. ECHO: a community video streaming system with interactive visual overlays

    NASA Astrophysics Data System (ADS)

    Cheung, Gene; Tan, Wai-tian; Shen, Bo; Ortega, Antonio

    2008-01-01

    We describe a networked video application where personalized avatars, controlled by a group of "hecklers", are overlaid on top of a real-time encoded video stream of an Internet game for multicast consumption. Rather than passively observing the streamed content individually, the interactivity of the controllable avatars, along with heckling voice exchange, engenders a sense of community during group viewing. We first describe how the system splits video into independent regions with and without avatars for processing in order to minimize complexity. Observing that the region with avatars is more delay-sensitive due to their interactivity, we then show that the regions can be logically packetized into separable sub-streams, and be transported and buffered with different delay requirements, so that the interactivity of the avatars can be maximized. The utility of our system extends beyond Internet game watching to general community streaming of live or pre-encoded video with visual overlays.

  20. Wide-area, real-time monitoring and visualization system

    DOEpatents

    Budhraja, Vikram S.; Dyer, James D.; Martinez Morales, Carlos A.

    2013-03-19

    A real-time performance monitoring system for monitoring an electric power grid. The electric power grid has a plurality of grid portions, each grid portion corresponding to one of a plurality of control areas. The real-time performance monitoring system includes a monitor computer for monitoring at least one of reliability metrics, generation metrics, transmission metrics, suppliers metrics, grid infrastructure security metrics, and markets metrics for the electric power grid. The data for metrics being monitored by the monitor computer are stored in a data base, and a visualization of the metrics is displayed on at least one display computer having a monitor. The at least one display computer in one said control area enables an operator to monitor the grid portion corresponding to a different said control area.

  1. Wide-area, real-time monitoring and visualization system

    DOEpatents

    Budhraja, Vikram S [Los Angeles, CA; Dyer, James D [La Mirada, CA; Martinez Morales, Carlos A [Upland, CA

    2011-11-15

    A real-time performance monitoring system for monitoring an electric power grid. The electric power grid has a plurality of grid portions, each grid portion corresponding to one of a plurality of control areas. The real-time performance monitoring system includes a monitor computer for monitoring at least one of reliability metrics, generation metrics, transmission metrics, suppliers metrics, grid infrastructure security metrics, and markets metrics for the electric power grid. The data for metrics being monitored by the monitor computer are stored in a data base, and a visualization of the metrics is displayed on at least one display computer having a monitor. The at least one display computer in one said control area enables an operator to monitor the grid portion corresponding to a different said control area.

  2. Mechanisms compensating for visual field restriction in adolescents with damage to the retro-geniculate visual system

    PubMed Central

    Jacobson, L; Lennartsson, F; Pansell, T; Öqvist Seimyr, G; Martin, L

    2012-01-01

    Background To describe visual field (VF) outcome in three adolescents with damage to the optic radiation and to focus on mechanisms that may compensate the practical functional limitations of VF defects. Design Descriptive, prospective multi-case study in a hospital setting. Participants Three teenagers with cerebral visual dysfunction because of damage to the retro-geniculate visual pathways. Methods Best-corrected visual acuity and eye alignment were assessed. Visual field function was tested with Goldmann perimetry, and with Rarebit, Humphrey Visual Field Analyzer and Esterman computerized techniques. Fixation was registered with video oculography during Rarebit examination. Magnetic resonance imaging of the brain illustrated brain damage and its relation to the posterior visual system. Results One of the three subjects had bilateral asymmetric white matter damage of immaturity, early-onset exotropia, and a relative homonymous VF defect, but normal binocular VF. The second subject also had bilateral asymmetric white matter damage of immaturity and showed an inferior right quadrantanopia, confirmed by the binocular field. Registration of fixation revealed automatic scanning during perimetry. The third subject had an almost total left homonymous hemianopia after resection of a brain tumour in the right temporal lobe. The hemianopia could be compensated for by fast voluntary scanning. Conclusion Congenital and later-acquired homonymous VF defects may, at least in young subjects, be compensated for by scanning. Exotropia may compensate VF defects and, therefore, the VF should be tested before strabismus surgery. PMID:22995940

  3. An Automated Visual Event Detection System for Cabled Observatory Video

    NASA Astrophysics Data System (ADS)

    Edgington, D. R.; Cline, D. E.; Mariette, J.

    2007-12-01

    The permanent presence of underwater cameras on oceanic cabled observatories, such as the Victoria Experimental Network Under the Sea (VENUS) and Eye-In-The-Sea (EITS) on Monterey Accelerated Research System (MARS), will generate valuable data that can move forward the boundaries of understanding the underwater world. However, sightings of underwater animal activities are rare, resulting in the recording of many hours of video with relatively few events of interest. The burden of video management and analysis often requires reducing the amount of video recorded and later analyzed. Sometimes enough human resources do not exist to analyze the video; the strains on human attention needed to analyze video demand an automated way to assist in video analysis. Towards this end, an Automated Visual Event Detection System (AVED) is in development at the Monterey Bay Aquarium Research Institute (MBARI) to address the problem of analyzing cabled observatory video. Here we describe the overall design of the system to process video data and enable science users to analyze the results. We present our results analyzing video from the VENUS observatory and test data from EITS deployments. This automated system for detecting visual events includes a collection of custom and open source software that can be run three ways: through a Web Service, through a Condor managed pool of AVED enabled compute servers, or locally on a single computer. The collection of software also includes a graphical user interface to preview or edit detected results and to setup processing options. To optimize the compute-intensive AVED algorithms, a parallel program has been implemented for high-data rate applications like the EITS instrument on MARS.

  4. Integrated Computational System for Aerodynamic Steering and Visualization

    NASA Technical Reports Server (NTRS)

    Hesselink, Lambertus

    1999-01-01

    In February of 1994, an effort from the Fluid Dynamics and Information Sciences Divisions at NASA Ames Research Center with McDonnel Douglas Aerospace Company and Stanford University was initiated to develop, demonstrate, validate and disseminate automated software for numerical aerodynamic simulation. The goal of the initiative was to develop a tri-discipline approach encompassing CFD, Intelligent Systems, and Automated Flow Feature Recognition to improve the utility of CFD in the design cycle. This approach would then be represented through an intelligent computational system which could accept an engineer's definition of a problem and construct an optimal and reliable CFD solution. Stanford University's role focused on developing technologies that advance visualization capabilities for analysis of CFD data, extract specific flow features useful for the design process, and compare CFD data with experimental data. During the years 1995-1997, Stanford University focused on developing techniques in the area of tensor visualization and flow feature extraction. Software libraries were created enabling feature extraction and exploration of tensor fields. As a proof of concept, a prototype system called the Integrated Computational System (ICS) was developed to demonstrate CFD design cycle. The current research effort focuses on finding a quantitative comparison of general vector fields based on topological features. Since the method relies on topological information, grid matching and vector alignment is not needed in the comparison. This is often a problem with many data comparison techniques. In addition, since only topology based information is stored and compared for each field, there is a significant compression of information that enables large databases to be quickly searched. This report will (1) briefly review the technologies developed during 1995-1997 (2) describe current technologies in the area of comparison techniques, (4) describe the theory of our new

  5. Long distance laser ultrasonic propagation imaging system for damage visualization

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Ryul; Shin, He-Jin; Chia, Chen Ciang; Dhital, Dipesh; Yoon, Dong-Jin; Huh, Yong-Hak

    2011-12-01

    Wind turbine blade failure is the most prominent and common type of damage occurring in operating wind turbine systems. Conventional nondestructive testing systems are not available for in situ wind turbine blades. We propose a portable long distance ultrasonic propagation imaging (LUPI) system that uses a laser beam targeting and scanning system to excite, from a long distance, acoustic emission sensors installed in the blade. An examination of the beam collimation effect using geometric parameters of a commercial 2 MW wind turbine provided Lamb wave amplitude increases of 41.5 and 23.1 dB at a distance of 40 m for symmetrical and asymmetrical modes, respectively, in a 2 mm-thick stainless steel plate. With this improvement in signal-to-noise ratio, a feasibility study of damage detection was conducted with a 5 mm-thick composite leading edge specimen. To develop a reliable damage evaluation system, the excitation/sensing technology and the associated damage visualization algorithm are equally important. Hence, our results provide a new platform based on anomalous wave propagation imaging (AWPI) methods with adjacent wave subtraction, reference wave subtraction, reference image subtraction, and the variable time window amplitude mapping method. The advantages and disadvantages of AWPI algorithms are reported in terms of reference data requirements, signal-to-noise ratios, and damage evaluation accuracy. The compactness and portability of the proposed UPI system are also important for in-field applications at wind farms.

  6. Distributed visual-target-surveillance system in wireless sensor networks.

    PubMed

    Wang, Xue; Wang, Sheng; Bi, Daowei

    2009-10-01

    A wireless sensor network (WSN) is a powerful unattended distributed measurement system, which is widely used in target surveillance because of its outstanding performance in distributed sensing and signal processing. This paper introduces a multiview visual-target-surveillance system in WSN, which can autonomously implement target classification and tracking with collaborative online learning and localization. The proposed system is a hybrid system of single-node and multinode fusion. It is constructed on a peer-to-peer (P2P)-based computing paradigm and consists of some simple but feasible methods for target detection and feature extraction. Importantly, a support-vector-machine-based semisupervised learning method is used to achieve online classifier learning with only unlabeled samples. To reduce the energy consumption and increase the accuracy, a novel progressive data-fusion paradigm is proposed for online learning and localization, where a feasible routing method is adopted to implement information transmission with the tradeoff between performance and cost. Experiment results verify that the proposed surveillance system is an effective, energy-efficient, and robust system for real-world application. Furthermore, the P2P-based progressive data-fusion paradigm can improve the energy efficiency and robustness of target surveillance.

  7. [Effect of work with computer monitors on the visual system].

    PubMed

    Niesłuchowska, M

    1994-03-01

    Computer users complain of numerous visual discomforts. The paper discusses those connected with eye fatigue and changes in visual functions associated with the work with monitor screens; these can be alleviated with an ergonomic organization of the work unit. There is a need for a determination of the requirements in visual functions for computer users.

  8. Visual Semantic Based 3D Video Retrieval System Using HDFS

    PubMed Central

    Kumar, C.Ranjith; Suguna, S.

    2016-01-01

    This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose, we intent to hitch on BOVW and Mapreduce in 3D framework. Instead of conventional shape based local descriptors, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook and histogram is produced. Further, matching is performed using soft weighting scheme with L2 distance function. As a final step, retrieved results are ranked according to the Index value and acknowledged to the user as a feedback .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we future the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy. PMID:28003793

  9. Visual Semantic Based 3D Video Retrieval System Using HDFS.

    PubMed

    Kumar, C Ranjith; Suguna, S

    2016-08-01

    This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose, we intent to hitch on BOVW and Mapreduce in 3D framework. Instead of conventional shape based local descriptors, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook and histogram is produced. Further, matching is performed using soft weighting scheme with L2 distance function. As a final step, retrieved results are ranked according to the Index value and acknowledged to the user as a feedback .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we future the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy.

  10. Therapeutic Options for Controlling Fluids in the Visual System

    NASA Technical Reports Server (NTRS)

    Curry, Kristina M.; Wotring, Virginia E.

    2014-01-01

    Visual Impairment/Intracranial Pressure (VIIP) is a newly recognized risk at NASA. The VIIP project examines the effect of long-term exposure to microgravity on vision of crewmembers before and after they return to Earth. Diamox (acetazolamide) is a medication which is used to decrease intraocular pressure; however, it carries a 3% risk of kidney stones. Astronauts are at a higher risk of kidney stones during spaceflight and the use Diamox would only increase the risk; therefore alternative therapies were investigated. Histamine 2 (H2) antagonist acid blockers such as cimetidine, ranitidine, famotidine and nizatidine are typically used to relieve the symptoms of gastroesophageal reflux disease (GERD). H2 receptors have been found in the human visual system, which has led to research on the use of H2 antagonist blockers to control fluid production in the human eye. Another potential therapeutic strategy is targeted at aquaporins, which are water channels that help maintain fluid homeostasis. Aquaporin antagonists are also known to affect intracranial pressure which can in turn alter intraocular pressure. Studies on aquaporin antagonists suggest high potential for effective treatment. The primary objective of this investigation is to review existing research on alternate medications or therapy to significantly reduce intracranial and intraocular pressure. A literature review was conducted. Even though we do not have all the answers quite yet, a considerable amount of information was discovered, and findings were narrowed, which should allow for more conclusive answers to be found in the near future.

  11. Active vision in marmosets: a model system for visual neuroscience.

    PubMed

    Mitchell, Jude F; Reynolds, John H; Miller, Cory T

    2014-01-22

    The common marmoset (Callithrix jacchus), a small-bodied New World primate, offers several advantages to complement vision research in larger primates. Studies in the anesthetized marmoset have detailed the anatomy and physiology of their visual system (Rosa et al., 2009) while studies of auditory and vocal processing have established their utility for awake and behaving neurophysiological investigations (Lu et al., 2001a,b; Eliades and Wang, 2008a,b; Osmanski and Wang, 2011; Remington et al., 2012). However, a critical unknown is whether marmosets can perform visual tasks under head restraint. This has been essential for studies in macaques, enabling both accurate eye tracking and head stabilization for neurophysiology. In one set of experiments we compared the free viewing behavior of head-fixed marmosets to that of macaques, and found that their saccadic behavior is comparable across a number of saccade metrics and that saccades target similar regions of interest including faces. In a second set of experiments we applied behavioral conditioning techniques to determine whether the marmoset could control fixation for liquid reward. Two marmosets could fixate a central point and ignore peripheral flashing stimuli, as needed for receptive field mapping. Both marmosets also performed an orientation discrimination task, exhibiting a saturating psychometric function with reliable performance and shorter reaction times for easier discriminations. These data suggest that the marmoset is a viable model for studies of active vision and its underlying neural mechanisms.

  12. Twenty Drosophila visual system cDNA clones: one is a homolog of human arrestin.

    PubMed Central

    Hyde, D R; Mecklenburg, K L; Pollock, J A; Vihtelic, T S; Benzer, S

    1990-01-01

    From a group of 436 Drosophila melanogaster cDNA clones, we selected 39 that are expressed exclusively or predominantly in the adult visual system. By sequence analysis, 20 of the clones appear to represent previously unreported distinct cDNAs. The corresponding transcripts are detected in the retina and optic lobes. The genes are scattered throughout the genome, some near mutations known to affect eye function. One of these clones has been identified, by sequence analysis, as the structural gene (Arr) for a Drosophila homolog of human arrestin. Vertebrate arrestin interacts with rhodopsin in phototransduction and has been associated with an autoimmune form of uveitis in primates. The presence of an arrestin homolog in Drosophila suggests that both the vertebrate and invertebrate phototransduction cascades are regulated in a similar manner. Images PMID:2105491

  13. Attitudes of older adults toward shooter video games: An initial study to select an acceptable game for training visual processing.

    PubMed

    McKay, Sandra M; Maki, Brian E

    2010-01-01

    A computer-based 'Useful Field of View' (UFOV) training program has been shown to be effective in improving visual processing in older adults. Studies of young adults have shown that playing video games can have similar benefits; however, these studies involved realistic and violent 'first-person shooter' (FPS) games. The willingness of older adults to play such games has not been established. OBJECTIVES: To determine the degree to which older adults would accept playing a realistic, violent FPS-game, compared to video games not involving realistic depiction of violence. METHODS: Sixteen older adults (ages 64-77) viewed and rated video-clip demonstrations of the UFOV program and three video-game genres (realistic-FPS, cartoon-FPS, fixed-shooter), and were then given an opportunity to try them out (30 minutes per game) and rate various features. RESULTS: The results supported a hypothesis that the participants would be less willing to play the realistic-FPS game in comparison to the less violent alternatives (p's<0.02). After viewing the video-clip demonstrations, 10 of 16 participants indicated they would be unwilling to try out the realistic-FPS game. Of the six who were willing, three did not enjoy the experience and were not interested in playing again. In contrast, all 12 subjects who were willing to try the cartoon-FPS game reported that they enjoyed it and would be willing to play again. A high proportion also tried and enjoyed the UFOV training (15/16) and the fixed-shooter game (12/15). DISCUSSION: A realistic, violent FPS video game is unlikely to be an appropriate choice for older adults. Cartoon-FPS and fixed-shooter games are more viable options. Although most subjects also enjoyed UFOV training, a video-game approach has a number of potential advantages (for instance, 'addictive' properties, low cost, self-administration at home). We therefore conclude that non-violent cartoon-FPS and fixed-shooter video games warrant further investigation as an

  14. Occipital-temporal Reduction and Sustained Visual Attention Deficit in Prenatal Alcohol Exposed Adults.

    PubMed

    Li, Zhihao; Ma, Xiangyang; Peltier, Scott; Hu, Xiaoping; Coles, Claire D; Lynch, Mary Ellen

    2008-03-01

    Visual attention problems have been reported in association with prenatal alcohol exposure (PAE). With related behavioral data documented in literature, further investigation of this PAE effect would benefit from integrating functional and anatomical imaging data to ascertain its neurobiological basis. The current study investigated the possible functional and anatomical bases for the PAE-related visual sustained attention deficit. Functional magnetic resonance imaging (fMRI) data were collected while the subjects performed a sustained visual attention task. High resolution, three dimensional anatomical images were also collected for morphometric evaluation. In the alcohol-affected subjects, we observed a significant white and gray matter volume reduction in the occipital-temporal area. Meanwhile, their fMRI activations in the same region resided more superiorly than that of the controls resulting in reduced activation in the ventral occipital-temporal area. The location of this PAE functional abnormality approximately matches that of the significant structural reduction. In addition to the well documented corpus callosum abnormalities observed in PAE subjects, the present results reveal a teratogenic effect on the occipital-temporal area. Furthermore, as the occipital-temporal area plays an important role in visual attention, the current observation suggests a neurobiological underpinning for the PAE related deficit in sustained visual attention.

  15. Determine the effect of neck muscle fatigue on dynamic visual acuity in healthy young adults

    PubMed Central

    Al Saif, Amer A.; Al Senany, Samira

    2015-01-01

    [Purpose] The aim of this study was to determine whether neck muscle fatigue affects dynamic visual acuity in healthy young participants. [Subjects and Methods] This study was a double-blinded, prospective, randomized, controlled trial. Thirty healthy young subjects (ages 21 to 30 years) participated in the study. Participants were randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group performed an exercise designed to induce neck muscle fatigue and the control group preformed non-fatiguing sham exercises. [Results] There were significant differences in mean dynamic visual acuity between the two groups (0.26±0.11 LogMar versus 0.003±0.02 LogMar). Subjects in the experimental group showed a significant decline in their dynamic visual acuity compared with the control group. Dynamic visual acuity strongly correlated with neck muscle fatigue (r = 0.79). No significant differences in joint position error were observed between the two groups and no significant correlations between joint position error and neck muscle fatigue were observed (r = 0.23). [Conclusion] The results of this study suggest that neck muscle fatigue negatively impacts dynamic visual acuity. Although not statistically significant, cervical spine proprioception as measured by the joint position error in the experimental group was diminished after fatigue. PMID:25642087

  16. Determine the effect of neck muscle fatigue on dynamic visual acuity in healthy young adults.

    PubMed

    Al Saif, Amer A; Al Senany, Samira

    2015-01-01

    [Purpose] The aim of this study was to determine whether neck muscle fatigue affects dynamic visual acuity in healthy young participants. [Subjects and Methods] This study was a double-blinded, prospective, randomized, controlled trial. Thirty healthy young subjects (ages 21 to 30 years) participated in the study. Participants were randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group performed an exercise designed to induce neck muscle fatigue and the control group preformed non-fatiguing sham exercises. [Results] There were significant differences in mean dynamic visual acuity between the two groups (0.26±0.11 LogMar versus 0.003±0.02 LogMar). Subjects in the experimental group showed a significant decline in their dynamic visual acuity compared with the control group. Dynamic visual acuity strongly correlated with neck muscle fatigue (r = 0.79). No significant differences in joint position error were observed between the two groups and no significant correlations between joint position error and neck muscle fatigue were observed (r = 0.23). [Conclusion] The results of this study suggest that neck muscle fatigue negatively impacts dynamic visual acuity. Although not statistically significant, cervical spine proprioception as measured by the joint position error in the experimental group was diminished after fatigue.

  17. Flight validation of a pulsed smoke flow visualization system

    NASA Technical Reports Server (NTRS)

    Ward, Donald T.; Dorsett, Kenneth M.

    1993-01-01

    A flow visualization scheme, designed to measure vortex fluid dynamics on research aircraft, was validated in flight. Strake vortex trajectories and axial core velocities were determined using pulsed smoke, high-speed video images, and semiautomated image edge detection hardware and software. Smoke was pulsed by using a fast-acting three-way valve. After being redesigned because of repeatedly jamming in flight, the valve shuttle operated flawlessly during the last two tests. A 25-percent scale, Gothic strake was used to generate vortex over the wing of a GA-7 Cougar and was operated at a local angle of attack of 22 degrees and Reynolds number of approximately 7.8 x 10(exp 5)/ft. Maximum axial velocities measured in the vortex core were between 1.75 and 1.95 times the freestream velocity. Analysis of the pulsed smoke system's affect on forebody vortices indicates that the system may reorient the forebody vortex system; however, blowing momentum coefficients normally used will have no appreciable affect on the leading-edge extension vortex system. It is recommended that a similar pulsed smoke system be installed on the F/A-18 High Angle Research Vehicle and that this approach be used to analyze vortex core dynamics during the remainder of its high-angle-of-attack research flights.

  18. Training-related changes in early visual processing of functionally illiterate adults: evidence from event-related brain potentials

    PubMed Central

    2013-01-01

    Background Event-related brain potentials (ERPs) were used to investigate training-related changes in fast visual word recognition of functionally illiterate adults. Analyses focused on the left-lateralized occipito-temporal N170, which represents the earliest processing of visual word forms. Event-related brain potentials were recorded from 20 functional illiterates receiving intensive literacy training for adults, 10 functional illiterates not participating in the training and 14 regular readers while they read words, pseudowords or viewed symbol strings. Subjects were required to press a button whenever a stimulus was immediately repeated. Results Attending intensive literacy training was associated with improvements in reading and writing skills and with an increase of the word-related N170 amplitude. For untrained functional illiterates and regular readers no changes in literacy skills or N170 amplitude were observed. Conclusions Results of the present study suggest that the word-related N170 can still be modulated in adulthood as a result of the improvements in literacy skills. PMID:24330622

  19. Physical Exercise Preserves Adult Visual Plasticity in Mice and Restores it after a Stroke in the Somatosensory Cortex

    PubMed Central

    Kalogeraki, Evgenia; Pielecka-Fortuna, Justyna; Hüppe, Janika M.; Löwel, Siegrid

    2016-01-01

    The primary visual cortex (V1) is widely used to study brain plasticity, which is not only crucial for normal brain function, such as learning and memory, but also for recovery after brain injuries such as stroke. In standard cage (SC) raised mice, experience-dependent ocular dominance (OD) plasticity in V1 declines with age and is compromised by a lesion in adjacent and distant cortical regions. In contrast, mice raised in an enriched environment (EE), exhibit lifelong OD plasticity and are protected from losing OD plasticity after a stroke-lesion in the somatosensory cortex. Since SC mice with an access to a running wheel (RW) displayed preserved OD plasticity during aging, we investigated whether physical exercise might also provide a plasticity promoting effect after a cortical stroke. To this end, we tested if adult RW-raised mice preserved OD plasticity after stroke and also if short-term running after stroke restored OD plasticity to SC mice. Indeed, unlike mice without a RW, adult RW mice continued to show OD plasticity even after stroke, and a 2 weeks RW experience after stroke already restored lost OD plasticity. Additionally, the experience-enabled increase of the spatial frequency and contrast threshold of the optomotor reflex of the open eye, normally lost after a stroke, was restored in both groups of RW mice. Our data suggest that physical exercise alone can not only preserve visual plasticity into old age, but also restore it after a cortical stroke. PMID:27708575

  20. Physical Exercise Preserves Adult Visual Plasticity in Mice and Restores it after a Stroke in the Somatosensory Cortex.

    PubMed

    Kalogeraki, Evgenia; Pielecka-Fortuna, Justyna; Hüppe, Janika M; Löwel, Siegrid

    2016-01-01

    The primary visual cortex (V1) is widely used to study brain plasticity, which is not only crucial for normal brain function, such as learning and memory, but also for recovery after brain injuries such as stroke. In standard cage (SC) raised mice, experience-dependent ocular dominance (OD) plasticity in V1 declines with age and is compromised by a lesion in adjacent and distant cortical regions. In contrast, mice raised in an enriched environment (EE), exhibit lifelong OD plasticity and are protected from losing OD plasticity after a stroke-lesion in the somatosensory cortex. Since SC mice with an access to a running wheel (RW) displayed preserved OD plasticity during aging, we investigated whether physical exercise might also provide a plasticity promoting effect after a cortical stroke. To this end, we tested if adult RW-raised mice preserved OD plasticity after stroke and also if short-term running after stroke restored OD plasticity to SC mice. Indeed, unlike mice without a RW, adult RW mice continued to show OD plasticity even after stroke, and a 2 weeks RW experience after stroke already restored lost OD plasticity. Additionally, the experience-enabled increase of the spatial frequency and contrast threshold of the optomotor reflex of the open eye, normally lost after a stroke, was restored in both groups of RW mice. Our data suggest that physical exercise alone can not only preserve visual plasticity into old age, but also restore it after a cortical stroke.

  1. Visual attention in preterm born adults: specifically impaired attentional sub-mechanisms that link with altered intrinsic brain networks in a compensation-like mode.

    PubMed

    Finke, Kathrin; Neitzel, Julia; Bäuml, Josef G; Redel, Petra; Müller, Hermann J; Meng, Chun; Jaekel, Julia; Daamen, Marcel; Scheef, Lukas; Busch, Barbara; Baumann, Nicole; Boecker, Henning; Bartmann, Peter; Habekost, Thomas; Wolke, Dieter; Wohlschläger, Afra; Sorg, Christian

    2015-02-15

    Although pronounced and lasting deficits in selective attention have been observed for preterm born individuals it is unknown which specific attentional sub-mechanisms are affected and how they relate to brain networks. We used the computationally specified 'Theory of Visual Attention' together with whole- and partial-report paradigms to compare attentional sub-mechanisms of pre- (n=33) and full-term (n=32) born adults. Resting-state fMRI was used to evaluate both between-group differences and inter-individual variance in changed functional connectivity of intrinsic brain networks relevant for visual attention. In preterm born adults, we found specific impairments of visual short-term memory (vSTM) storage capacity while other sub-mechanisms such as processing speed or attentional weighting were unchanged. Furthermore, changed functional connectivity was found in unimodal visual and supramodal attention-related intrinsic networks. Among preterm born adults, the individual pattern of changed connectivity in occipital and parietal cortices was systematically associated with vSTM in such a way that the more distinct the connectivity differences, the better the preterm adults' storage capacity. These findings provide first evidence for selectively changed attentional sub-mechanisms in preterm born adults and their relation to altered intrinsic brain networks. In particular, data suggest that cortical changes in intrinsic functional connectivity may compensate adverse developmental consequences of prematurity on visual short-term storage capacity.

  2. Conceptual design study for an advanced cab and visual system, volume 2

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    The performance, design, construction and testing requirements are defined for developing an advanced cab and visual system. The rotorcraft system integration simulator is composed of the advanced cab and visual system and the rotorcraft system motion generator, and is part of an existing simulation facility. User's applications for the simulator include rotorcraft design development, product improvement, threat assessment, and accident investigation.

  3. BrainFrame: a knowledge visualization system for the neurosciences

    NASA Astrophysics Data System (ADS)

    Barnes, Steven J.; Shaw, Chris D.

    2009-01-01

    Neuroscience has benefited from an explosion of new experimental techniques; many have only become feasible in the wake of improvements in computing speed and data storage. At the same time, these new computation-intensive techniques have led to a growing gulf between the data and the knowledge extracted from those data. That is, in the neurosciences there is a paucity of effective knowledge management techniques and an accelerating accumulation of experimental data. The purpose of the project described in the present paper is to create a visualization of the knowledge base of the neurosciences. At run-time, this 'BrainFrame' project accesses several web-based ontologies and generates a semantically zoomable representation of any one of many levels of the human nervous system.

  4. Detection of a white dwarf in a visual binary system

    NASA Technical Reports Server (NTRS)

    Boehm-Vitense, Erika

    1980-01-01

    The F6 giant HD 160365 was detected to have a white dwarf companion about 8 arcsec south of the star. The UV energy distribution observed with International Ultraviolet Explorer (IUE) shows that the white dwarf has an effective temperature of 23,000 +/- 2,000 K. If log g = 8 the Ly(alpha) profile indicates an effective temperature around 24,500 K. Using the theoretical models, one finds a visual magnitude of m(sub v) is approximately 16.5. For T(sub eff) = 24,500 K one expects for a white dwarf a luminosity of log L/solar luminosity is approximately -1.3 and M(sub V) is approximately 10.67. This gives a distance modulus for the system of m(sub v) - M(sub V) = 5.83 and an absolute magnitude M(sub v) = 0.3 for the giant.

  5. Evaluating System Parameters on a Dragonfly using Simulation and Visualization

    SciTech Connect

    Bhatele, Abhinav; Jain, Nikhil; Livnat, Yarden; Pascucci, Valerio; Bremer, Peer-Timo

    2015-04-24

    The dragon y topology is becoming a popular choice for build- ing high-radix, low-diameter networks with high-bandwidth links. Even with a powerful network, preliminary experi- ments on Edison at NERSC have shown that for communica- tion heavy applications, job interference and thus presumably job placement remains an important factor. In this paper, we explore the e ects of job placement, job sizes, parallel workloads and network con gurations on network through- put to better understand inter-job interference. We use a simulation tool called Damsel y to model the network be- havior of Edison and study the impact of various system parameters on network throughput. Parallel workloads based on ve representative communication patters are used and the simulation studies on up to 131,072 cores are aided by a new visualization of the dragon y network.

  6. Real-time, interactive, visually updated simulator system for telepresence

    NASA Technical Reports Server (NTRS)

    Schebor, Frederick S.; Turney, Jerry L.; Marzwell, Neville I.

    1991-01-01

    Time delays and limited sensory feedback of remote telerobotic systems tend to disorient teleoperators and dramatically decrease the operator's performance. To remove the effects of time delays, key components were designed and developed of a prototype forward simulation subsystem, the Global-Local Environment Telerobotic Simulator (GLETS) that buffers the operator from the remote task. GLETS totally immerses an operator in a real-time, interactive, simulated, visually updated artificial environment of the remote telerobotic site. Using GLETS, the operator will, in effect, enter into a telerobotic virtual reality and can easily form a gestalt of the virtual 'local site' that matches the operator's normal interactions with the remote site. In addition to use in space based telerobotics, GLETS, due to its extendable architecture, can also be used in other teleoperational environments such as toxic material handling, construction, and undersea exploration.

  7. Visual tracking in stereo. [by computer vision system

    NASA Technical Reports Server (NTRS)

    Saund, E.

    1981-01-01

    A method is described for visual object tracking by a computer vision system using TV cameras and special low-level image processing hardware. The tracker maintains an internal model of the location, orientation, and velocity of the object in three-dimensional space. This model is used to predict where features of the object will lie on the two-dimensional images produced by stereo TV cameras. The differences in the locations of features in the two-dimensional images as predicted by the internal model and as actually seen create an error signal in the two-dimensional representation. This is multiplied by a generalized inverse Jacobian matrix to deduce the error in the internal model. The procedure repeats to update the internal model of the object's location, orientation and velocity continuously.

  8. Microlens arrays in the complex visual system of Cretaceous echinoderms.

    PubMed

    Gorzelak, Przemysław; Salamon, Mariusz A; Lach, Rafał; Loba, Michał; Ferré, Bruno

    2014-04-01

    It has long been assumed that photosensitivity in echinoderms is mainly related to diffuse photoreception mediated by photosensitive regions embedded within the dermis. Recent studies, however, have shown that some extant echinoderms may also display modified ossicles with microlenses acting as sophisticated photosensory organs. Thanks to their remarkable properties, these calcitic microlenses serve as an inspiration for scientists across various disciplines among which bio-inspired engineering. However, the evolutionary origins of these microlenses remain obscure. Here we provide microstructural evidence showing that analogous spherical calcitic lenses had been acquired in some brittle stars and starfish of Poland by the Late Cretaceous (Campanian, ~79 Ma). Specimens from Poland described here had a highly developed visual system similar to that of modern forms. We suggest that such an optimization of echinoderm skeletons for both mechanical and optical purposes reflects escalation-related adaptation to increased predation pressure during the so-called Mesozoic Marine Revolution.

  9. Detection of a white dwarf in a visual binary system

    NASA Technical Reports Server (NTRS)

    Boehm-Vitense, Erika

    1992-01-01

    The F6 giant HD 160365 was detected to have a white dwarf companion about 8 arcsec south of the star. The UV energy distribution observed with IUE shows that the white dwarf has an effective temperature of 23,000 +/- 2000 K. If log g = 8 the Lya profile indicates an effective temperature around 24,500 K. Using the theoretical models by Wesemael et al. (1980) one finds a visual magnitude of m(V) about 16.5. For T(eff) = 24,500 K one expects for a white dwarf a luminosity of log L/L(solar) about 1.3 and M(V) about 10.67. This gives a distance modulus for the system of m(V) - M(V) = 5.83 and an absolute magnitude M(V)= 0.3 for the giant.

  10. Population-based assessment of visual impairment among ethnic Dai adults in a rural community in China

    PubMed Central

    Yang, Wen-Yan; Li, Jun; Zhao, Chun-Hua; Qian, Deng-Juan; Niu, Zhiqiang; Shen, Wei; Yuan, Yuansheng; Zhong, Hua; Pan, Chen-Wei

    2016-01-01

    Dai ethnicity is one of the major Chinese ethnic minorities with a population of about 1.2 million. We aimed to determine the prevalence and potential causes of visual impairment (VI) among ethnic Dai adults aged 50 years or older in a rural community in China. A population-based survey including 2163 ethnic Dai people (80.5%) was undertaken using a random cluster sampling strategy. The detailed eye examination was performed after pupil dilation by trained study ophthalmologists and optometrists. Presenting visual acuity (PVA) and best-corrected visual acuity (BCVA) was measured using the Early Treatment Diabetic Retinopathy Study logMAR chart and VI was defined as a VA of less than 20/63 in the better-seeing eye. The overall prevalence of presenting blindness and low vision was 3.0% (95% CI, 2.3–3.7) and 13.3% (95% CI, 11.9–14.8), respectively. The prevalence estimates were reduced to 2.1% (95% CI, 1.5–2.8) and 6.7% (95% CI, 5.7–7.8) when BCVA was considered. Men were more likely to be affected by low vision but less likely to be blind compared with women. Cataract accounted for 62.7% of presenting low vision and 68.8% of presenting blindness, respectively. In conclusion, VI was a significant health concern in Dai Chinese in China. PMID:26932265

  11. The degree of kinship and its association with reciprocity and exchange in the relationships of visually impaired older adults

    PubMed Central

    Flaig, Katherina N.-L.; Reinhardt, Joann P.

    2009-01-01

    This study draws on an evolutionary model of exchange in relationships to examine the nature of perceived reciprocity in the context of kin and non-kin relationships among a sample of visually impaired older adults (age 63–99). Further, we examined the direct and moderating impact of functional impairment and adaptation to visual impairment on the nature of perceived reciprocity. Results showed that the greater the degree of genetic relatedness the more imbalanced the exchange. It was also found that degree of adaptation to visual impairment moderated the association between genetic relatedness and perceived exchange, such that the greater the degree of genetic relatedness the more people reported they gave rather than received except at very low levels of adaptation, when people received more than they gave the greater the degree of genetic relatedness. Thus, an evolutionary model was supported such that imbalanced exchange was found more with greater degrees of genetic relatedness, but the direction of exchange was different for high versus low levels of adaptation to vision impairment. PMID:20160974

  12. Adults with dyslexia demonstrate large effects of crowding and detrimental effects of distractors in a visual tilt discrimination task.

    PubMed

    Cassim, Rizan; Talcott, Joel B; Moores, Elisabeth

    2014-01-01

    Previous research has shown that adults with dyslexia (AwD) are disproportionately impacted by close spacing of stimuli and increased numbers of distractors in a visual search task compared to controls [1]. Using an orientation discrimination task, the present study extended these findings to show that even in conditions where target search was not required: (i) AwD had detrimental effects of both crowding and increased numbers of distractors; (ii) AwD had more pronounced difficulty with distractor exclusion in the left visual field and (iii) measures of crowding and distractor exclusion correlated significantly with literacy measures. Furthermore, such difficulties were not accounted for by the presence of covarying symptoms of ADHD in the participant groups. These findings provide further evidence to suggest that the ability to exclude distracting stimuli likely contributes to the reported visual attention difficulties in AwD and to the aetiology of literacy difficulties. The pattern of results is consistent with weaker and asymmetric attention in AwD.

  13. Adults with Dyslexia Demonstrate Large Effects of Crowding and Detrimental Effects of Distractors in a Visual Tilt Discrimination Task

    PubMed Central

    Cassim, Rizan; Talcott, Joel B.; Moores, Elisabeth

    2014-01-01

    Previous research has shown that adults with dyslexia (AwD) are disproportionately impacted by close spacing of stimuli and increased numbers of distractors in a visual search task compared to controls [1]. Using an orientation discrimination task, the present study extended these findings to show that even in conditions where target search was not required: (i) AwD had detrimental effects of both crowding and increased numbers of distractors; (ii) AwD had more pronounced difficulty with distractor exclusion in the left visual field and (iii) measures of crowding and distractor exclusion correlated significantly with literacy measures. Furthermore, such difficulties were not accounted for by the presence of covarying symptoms of ADHD in the participant groups. These findings provide further evidence to suggest that the ability to exclude distracting stimuli likely contributes to the reported visual attention difficulties in AwD and to the aetiology of literacy difficulties. The pattern of results is consistent with weaker and asymmetric attention in AwD. PMID:25184299

  14. Visual, Auditory, and Cross Modal Sensory Processing in Adults with Autism: An EEG Power and BOLD fMRI Investigation

    PubMed Central

    Hames, Elizabeth’ C.; Murphy, Brandi; Rajmohan, Ravi; Anderson, Ronald C.; Baker, Mary; Zupancic, Stephen; O’Boyle, Michael; Richman, David

    2016-01-01

    Electroencephalography (EEG) and blood oxygen level dependent functional magnetic resonance imagining (BOLD fMRI) assessed the neurocorrelates of sensory processing of visual and auditory stimuli in 11 adults with autism (ASD) and 10 neurotypical (NT) controls between the ages of 20–28. We hypothesized that ASD performance on combined audiovisual trials would be less accurate with observable decreased EEG power across frontal, temporal, and occipital channels and decreased BOLD fMRI activity in these same regions; reflecting deficits in key sensory processing areas. Analysis focused on EEG power, BOLD fMRI, and accuracy. Lower EEG beta power and lower left auditory cortex fMRI activity were seen in ASD compared to NT when they were presented with auditory stimuli as demonstrated by contrasting the activity from the second presentation of an auditory stimulus in an all auditory block vs. the second presentation of a visual stimulus in an all visual block (AA2-VV2).We conclude that in ASD, combined audiovisual processing is more similar than unimodal processing to NTs. PMID:27148020

  15. Visual, Auditory, and Cross Modal Sensory Processing in Adults with Autism: An EEG Power and BOLD fMRI Investigation.

    PubMed

    Hames, Elizabeth' C; Murphy, Brandi; Rajmohan, Ravi; Anderson, Ronald C; Baker, Mary; Zupancic, Stephen; O'Boyle, Michael; Richman, David

    2016-01-01

    Electroencephalography (EEG) and blood oxygen level dependent functional magnetic resonance imagining (BOLD fMRI) assessed the neurocorrelates of sensory processing of visual and auditory stimuli in 11 adults with autism (ASD) and 10 neurotypical (NT) controls between the ages of 20-28. We hypothesized that ASD performance on combined audiovisual trials would be less accurate with observable decreased EEG power across frontal, temporal, and occipital channels and decreased BOLD fMRI activity in these same regions; reflecting deficits in key sensory processing areas. Analysis focused on EEG power, BOLD fMRI, and accuracy. Lower EEG beta power and lower left auditory cortex fMRI activity were seen in ASD compared to NT when they were presented with auditory stimuli as demonstrated by contrasting the activity from the second presentation of an auditory stimulus in an all auditory block vs. the second presentation of a visual stimulus in an all visual block (AA2-VV2).We conclude that in ASD, combined audiovisual processing is more similar than unimodal processing to NTs.

  16. Age-Related Visual Changes and Their Impications for the Motor Skill Performance of Older Adults.

    ERIC Educational Resources Information Center

    Haywood, Kathleen M.; Trick, Linda R.

    Physical changes in and conditions of the eye associated with the normal aging process are discussed with reference to their impact on performance in physical and recreational activities. Descriptions are given of characteristic changes in visual acuity in the areas of: (1) presbyopia (inability to clearly focus near images); (2) sensitivity to…

  17. Factors Predicting Post-High School Employment for Young Adults with Visual Impairments

    ERIC Educational Resources Information Center

    McDonnall, Michele Capella

    2010-01-01

    Although low levels of employment among transition-age youth with visual impairments (VI) have long been a concern, empirical research in this area is very limited. The purpose of this study was to identify factors that predict future employment for this population and to compare these factors to the factors that predict employment for the general…

  18. Effect of Playing a Video Game on Adults' and Adolescents' Spatial Visualization.

    ERIC Educational Resources Information Center

    Pepin, Michel; Dorval, Michel

    This paper presents the results of two studies which were performed to assess the effects of the practice of an interactive video game on spatial visualization test scores. The first study used 70 Laval University undergraduate students as subjects, while subjects for the second study were 101 seventh grade students from the area of Quebec City.…

  19. Stress Constellations and Coping Styles of Older Adults with Age-Related Visual Impairment

    ERIC Educational Resources Information Center

    Lee, Kyoung Othelia; Brennan, Mark

    2006-01-01

    Narrative data from two earlier studies of adaptation to age-related visual impairment were examined for constellations of stressors and coping styles. In the course of previous qualitative analyses, the researchers identified stress and coping codes according to behavioral, psychological, and social domains using a grounded theory approach. In…

  20. Learning of Grammar-Like Visual Sequences by Adults with and without Language-Learning Disabilities

    ERIC Educational Resources Information Center

    Aguilar, Jessica M.; Plante, Elena

    2014-01-01

    Purpose: Two studies examined learning of grammar-like visual sequences to determine whether a general deficit in statistical learning characterizes this population. Furthermore, we tested the hypothesis that difficulty in sustaining attention during the learning task might account for differences in statistical learning. Method: In Study 1,…

  1. Assistive Device Use in Visually Impaired Older Adults: Role of Control Beliefs

    ERIC Educational Resources Information Center

    Becker, Stefanie; Wahl, Hans-Werner; Schilling, Oliver; Burmedi, David

    2005-01-01

    Purpose: We investigate whether psychological control, conceptually framed within the life-span theory of control by Heckhausen and Schulz, drives assistive device use in visually impaired elders. In particular, we expect the two primary control modes differentiated in the life-span theory of control (i.e., selective primary and compensatory…

  2. Investigating Visual-Tactile Interactions over Time and Space in Adults with Autism

    ERIC Educational Resources Information Center

    Poole, Daniel; Gowen, Emma; Warren, Paul A.; Poliakoff, Ellen

    2015-01-01

    It has been suggested that the sensory symptoms which affect many people with autism spectrum conditions (ASC) may be related to alterations in multisensory processing. Typically, the likelihood of interactions between the senses increases when information is temporally and spatially coincident. We explored visual-tactile interactions in adults…

  3. The combined effect of sleep and time of day on emotion decoding from dynamic visual cues in older adults

    PubMed Central

    Tsokanaki, Paraskevi; Moraitou, Despina; Papantoniou, Georgia

    2016-01-01

    It is well known that night sleep is a decisive factor for the effective functioning of the human body and mind. In addition to the role of sleep, older adults report that they are “morning types” and that their cognitive and emotional abilities seem to be at a higher level in the morning hours. In this vein, this study is aimed at examining the effect of sleep combined with the “time of day” condition on a specific ability that is crucial for interpersonal communication, namely, emotion recognition, in older adults. Specifically, the study compared older adults’ performance in decoding emotions from ecologically valid, dynamic visual cues, in two conditions: “early in the morning and after night sleep”, and “in the afternoon and after many hours since night sleep”. An emotion recognition task was administered twice to 37 community-dwelling older adults. The results showed a statistically significant higher performance in the morning in decoding all emotions presented, compared to the afternoon condition. Pleasant surprise, sadness, and anxiety were revealed as the most difficult emotions to be recognized in the afternoon condition. PMID:27621639

  4. Pharmacotherapy for Adults with Tumors of the Central Nervous System

    PubMed Central

    Schor, Nina F.

    2009-01-01

    Tumors of the adult central nervous system are among the most common and most chemoresistant neoplasms. Malignant tumors of the brain and spinal cord collectively account for approximately 1.3% of all cancers and 2.2% of all cancer-related deaths. Novel pharmacological approaches to nervous system tumors are urgently needed. This review presents the current approaches and challenges to successful pharmacotherapy of adults with malignant tumors of the central nervous system and discusses novel approaches aimed at overcoming these challenges. PMID:19091301

  5. Iterative development of visual control systems in a research vivarium.

    PubMed

    Bassuk, James A; Washington, Ida M

    2014-01-01

    The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI) methodology, a lean approach to management at Seattle Children's (Hospital, Research Institute, Foundation), would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart's Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and selected Principles

  6. Iterative Development of Visual Control Systems in a Research Vivarium

    PubMed Central

    Bassuk, James A.; Washington, Ida M.

    2014-01-01

    The goal of this study was to test the hypothesis that reintroduction of Continuous Performance Improvement (CPI) methodology, a lean approach to management at Seattle Children’s (Hospital, Research Institute, Foundation), would facilitate engagement of vivarium employees in the development and sustainment of a daily management system and a work-in-process board. Such engagement was implemented through reintroduction of aspects of the Toyota Production System. Iterations of a Work-In-Process Board were generated using Shewhart’s Plan-Do-Check-Act process improvement cycle. Specific attention was given to the importance of detecting and preventing errors through assessment of the following 5 levels of quality: Level 1, customer inspects; Level 2, company inspects; Level 3, work unit inspects; Level 4, self-inspection; Level 5, mistake proofing. A functioning iteration of a Mouse Cage Work-In-Process Board was eventually established using electronic data entry, an improvement that increased the quality level from 1 to 3 while reducing wasteful steps, handoffs and queues. A visual workplace was realized via a daily management system that included a Work-In-Process Board, a problem solving board and two Heijunka boards. One Heijunka board tracked cage changing as a function of a biological kanban, which was validated via ammonia levels. A 17% reduction in cage changing frequency provided vivarium staff with additional time to support Institute researchers in their mutual goal of advancing cures for pediatric diseases. Cage washing metrics demonstrated an improvement in the flow continuum in which a traditional batch and queue push system was replaced with a supermarket-type pull system. Staff engagement during the improvement process was challenging and is discussed. The collective data indicate that the hypothesis was found to be true. The reintroduction of CPI into daily work in the vivarium is consistent with the 4P Model of the Toyota Way and selected

  7. Embodiments, visualizations, and immersion with enactive affective systems

    NASA Astrophysics Data System (ADS)

    Domingues, Diana; Miosso, Cristiano J.; Rodrigues, Suélia F.; Silva Rocha Aguiar, Carla; Lucena, Tiago F.; Miranda, Mateus; Rocha, Adson F.; Raskar, Ramesh

    2014-02-01

    Our proposal in Bioart and Biomedical Engineering for a ective esthetics focuses on the expanded sensorium and investigates problems regarding enactive systems. These systems enhance the sensorial experiences and amplify kinesthesia by adding the sensations that are formed in response to the physical world, which aesthetically constitutes the principle of synaesthesia. In this paper, we also present enactive systems inside the CAVE, con guring compelling experiences in data landscapes and human a ective narratives. The interaction occurs through the acquisition, data visualization and analysis of several synchronized physiological signals, to which the landscapes respond and provide immediate feedback, according to the detected participants' actions and the intertwined responses of the environment. The signals we use to analyze the human states include the electrocardiography (ECG) signal, the respiratory ow, the galvanic skin response (GSR) signal, plantar pressures, the pulse signal and others. Each signal is collected by using a speci cally designed dedicated electronic board, with reduced dimensions, so it does not interfere with normal movements, according to the principles of transparent technologies. Also, the electronic boards are implemented in a modular approach, so they are independent, and can be used in many di erent desired combinations, and at the same time provide synchronization between the collected data.

  8. Human visual system-based smoking event detection

    NASA Astrophysics Data System (ADS)

    Odetallah, Amjad D.; Agaian, Sos S.

    2012-06-01

    Human action (e.g. smoking, eating, and phoning) analysis is an important task in various application domains like video surveillance, video retrieval, human-computer interaction systems, and so on. Smoke detection is a crucial task in many video surveillance applications and could have a great impact to raise the level of safety of urban areas, public parks, airplanes, hospitals, schools and others. The detection task is challenging since there is no prior knowledge about the object's shape, texture and color. In addition, its visual features will change under different lighting and weather conditions. This paper presents a new scheme of a system for detecting human smoking events, or small smoke, in a sequence of images. In developed system, motion detection and background subtraction are combined with motion-region-saving, skin-based image segmentation, and smoke-based image segmentation to capture potential smoke regions which are further analyzed to decide on the occurrence of smoking events. Experimental results show the effectiveness of the proposed approach. As well, the developed method is capable of detecting the small smoking events of uncertain actions with various cigarette sizes, colors, and shapes.

  9. Application Of Expert System Techniques To A Visual Tracker

    NASA Astrophysics Data System (ADS)

    Myler, Harley R.; Thompson, Wiley E.; Flachs, Gerald M.

    1985-04-01

    A structure for visual tracking system is presented which relies on information developed from previous tracking scenarios stored in a knowledge base to enhance tracking performance. The system is comprised of a centroid tracker front end which supplies segmented image features to a data reduction algorithm which holds the reduced data in a temporary data base relation. This relation is then classified vio two separate modes, learn and track. Under learn mode, an external teacher-irector operator provides identification and weighting cues for membership in a long-term storage relation within a knowledge base. Track mode operates autonomously from the learn mode where the system determines feature validity by applying fuzzy set membership criteria to previously stored track information in the database. Results determined from the classification generate tracker directives which either enhance or permit current tracking to continue or cause the tracker to search for alternate targets based upon analysis of a global target tracking list. The classification algorithm is based on correlative analysis of the tracker's segmented output presentation after low pass filtering derives lower order harmonics of the feature. The fuzzy set membership criteria is based on size, rotation, Irame location, and past history of the feature. The first three factors are lin-ear operations on the spectra, while the last is generated as a context relation in the knowledge base. The context relation interlinks data between features to facilitate tracker operation during feature occlusion or presence of countermeasures.

  10. Preliminary design of an intermittent smoke flow visualization system

    NASA Technical Reports Server (NTRS)

    Ward, Donald T.; Myatt, James H.

    1993-01-01

    A prototype intermittent flow visualization system that was designed to study vortex flow field dynamics has been constructed and tested through its ground test phase. It produces discrete pulses of dense white smoke consisting of particles of terephthalic acid by the pulsing action of a fast-acting three-way valve. The trajectories of the smoke pulses can be tracked by a video imaging system without intruding in the flow around in flight. Two methods of pulsing the smoke were examined. The simplest and safest approach is to simply divert the smoke between the two outlet ports on the valve; this approach should be particularly effective if it were desired to inject smoke at two locations during the same test event. The second approach involves closing off one of the outlet ports to momentarily block the flow. The second approach requires careful control of valve dwell times to avoid excessive pressure buildup within the cartridge container. This method also increases the velocity of the smoke injected into the flow. The flow of the smoke has been blocked for periods ranging from 30 to 80 milliseconds, depending on the system volume and the length of time the valve is allowed to remain open between valve closings.

  11. The visual system of the Australian 'Redeye' cicada (Psaltoda moerens).

    PubMed

    Ribi, Willi A; Zeil, Jochen

    2015-11-01

    We investigated the functional anatomy of the visual system in the Australian 'Redeye' cicada Psaltoda moerens, including compound eyes and ocelli. The compound eyes have large visual fields, about 7500 ommatidia per eye and binocular overlaps of 10-15° in the frontal and of 50-60° in the dorsal visual field. The diameters of corneal facet lenses range between 22 and 34 μm and the lenses are unusually long with up to 100 μm in some eye regions. In the posterior part of the eyes, the hexagonal facet array changes to a square lattice. The compound eyes are of the eucone apposition type with 8 retinular cells contributing to a fused rhabdom in each ommatidium. The red eye colour is due to the pigment granules in the secondary pigment cells. We found a small Dorsal Rim Area (DRA), in which rhabdom cross-sections are rectangular rather than round. The cross-sections of DRA rhabdoms do not systematically change orientation along the length of the rhabdom, indicating that microvilli directions do not twist, which would make retinular cells in the DRA polarization sensitive. The three ocelli have unusual lenses with a champagne-cork shape in longitudinal sections. Retinular cells are short in the dorsal and ventral part of the retinae, and long in their equatorial part. Ocellar rhabdoms are short (<10 μm), positioned close to the corneagenous layer and are formed by pairs of retinular cells. In cross-section, the rhabdomeres are 2-5 μm long and straight. The red colour of ocelli is produced by screening pigments that form an iris around the base of the ocellar lens and by screening pigments between the ocellar retinular cells. We discuss the organization of the compound eye rhabdom, the organization of the ocelli and the presence of a DRA in the light of what is known about Hemipteran compound eyes. We note in particular that cicadas are the only Hemipteran group with fused rhabdoms, thus making Hemiptera an interesting case to study the evolution of open rhabdoms

  12. Toward a Learner-Centered System for Adult Learning

    ERIC Educational Resources Information Center

    Hermans, Henry; Kalz, Marco; Koper, Rob

    2013-01-01

    Purpose: The purpose of this paper is to present an e-learning system that integrates the use of concepts of virtual learning environments, personal learning environments, and social network sites. The system is based on a learning model which comprises and integrates three learning contexts for the adult learner: the formal, instructional…

  13. Exploring Motivational System Theory within the Context of Adult Education

    ERIC Educational Resources Information Center

    Hutto, Debra Jean

    2013-01-01

    Adult Basic Education (ABE) and the General Equivalency Diploma (GED) programs serve those students who, for whatever reason, have left the educational system without attaining a regular high school diploma. Because of the manner in which they may have left the school system, many have negative emotions and personal agency beliefs hindering their…

  14. Rapid Detection of Visually Provocative Animals by Preschool Children and Adults

    ERIC Educational Resources Information Center

    Penkunas, Michael J.; Coss, Richard G.

    2013-01-01

    The ability to detect dangerous animals rapidly in complex landscapes has been historically important during human evolution. Previous research has shown that snake images are more readily detected than images of benign animals. To provide a stringent test of superior snake detection in preschool children and adults, Experiment 1 consisted of two…

  15. Adapting Advanced Information Technology Network Training for Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Armstrong, Helen L.; Murray, Iain D.

    2010-01-01

    This article describes an accessible e-learning environment that was designed to deliver advanced IT skills to legally blind students in preparation for employment. The aim was to convert industry-standard training materials in print into accessible formats and to deliver the learning materials in ways that are more suited to adult students with…

  16. Preschool-age children and adults flexibly shift their preferences for auditory versus visual modalities but do not exhibit auditory dominance.

    PubMed

    Noles, Nicholaus S; Gelman, Susan A

    2012-07-01

    The goal of this study was to evaluate the claim that young children display preferences for auditory stimuli over visual stimuli. This study was motivated by concerns that the visual stimuli employed in prior studies were considerably more complex and less distinctive than the competing auditory stimuli, resulting in an illusory preference for auditory cues. Across three experiments, preschool-age children and adults were trained to use paired audio-visual cues to predict the location of a target. At test, the cues were switched so that auditory cues indicated one location and visual cues indicated the opposite location. In contrast to prior studies, preschool-age children did not exhibit auditory dominance. Instead, children and adults flexibly shifted their preferences as a function of the degree of contrast within each modality, with high contrast leading to greater use.

  17. Hemispheric lateralization of bilaterally presented homologous visual and auditory stimuli in normal adults, normal children, and children with central auditory dysfunction.

    PubMed

    Bellis, Teri James; Billiet, Cassie; Ross, Jody

    2008-04-01

    Two experiments were conducted to examine the performance of normal adults, normal children, and children diagnosed with central auditory dysfunction presumed to involve the interhemispheric pathways on a dichotic digits test in common clinical use for the diagnosis of central auditory processing disorder (CAPD) and its corresponding visual analog. Results of the first experiment revealed a significant right ear advantage (REA) for the dichotic listening task and a left-visual-field advantage (LVFA) for the corresponding visual analog in normal adults and children. In the second experiment, results revealed a significantly larger REA in the children with CAPD as compared to the normal children. Results also revealed a reversed cerebral asymmetry (RVFA) for the children with CAPD on the visual task. Significant cross-modal correlations suggest that the two tasks may reflect, at least in part, similar interhemispheric processing mechanisms in children. Findings are discussed in relation to differential diagnosis and modality-specificity of CAPD.

  18. The effects of adults' affective expression and direction of visual gaze on 12-month-olds' visual preferences for an object following a 5-minute, 1-day, or 1-month delay.

    PubMed

    Flom, Ross; Johnson, Sarah

    2011-03-01

    Between 12- and 14 months of age infants begin to use another's direction of gaze and affective expression in learning about various objects and events. What is not well understood is how long infants' behaviour towards a previously unfamiliar object continues to be influenced following their participation in circumstances of social referencing. In this experiment, we examined infants' sensitivity to an adult's direction of gaze and their visual preference for one of two objects following a 5-min, 1-day, or 1-month delay. Ninety-six 12-month-olds participated. For half of the infants during habituation (i.e., familiarization), the adults' direction of gaze was directed towards an unfamiliar object (look condition). For the remaining half of the infants during habituation, the adults' direction of gaze was directed away from the unfamiliar object (look-away condition). All infants were habituated to two events. One event consisted of an adult looking towards (look condition) or away from (look-away condition) an object while facially and vocally conveying a positive affective expression. The second event consisted of the same adult looking towards or away from a different object while conveying a disgusted affective expression. Following the habituation phase and a 5-min, 1-day, or 1-month delay, infants' visual preference was assessed. During the visual preference phase, infants saw the two objects side by side where the adult conveying the affective expression was not visible. Results of the visual preference phase indicate that infants in the look condition showed a significant preference for object previously paired with the positive affect following a 5-min and 1-day delay. No significant visual preference was found in the look condition following a 1-month delay. No significant preferences were found at any retention interval in the look-away condition. Results are discussed in terms of early learning, social referencing, and early memory.

  19. Verbal to visual code switching improves working memory in older adults: an fMRI study.

    PubMed

    Osaka, Mariko; Otsuka, Yuki; Osaka, Naoyuki

    2012-01-01

    The effect of verbal to visual code switching training on working memory performance was investigated in individuals aged 63 and older. During verbal working memory task performance, the training group (n = 25) was introduced to a verbal to visual code switching strategy while the control group (n = 25) was not exposed to such a strategy. Working memory recognition accuracy was enhanced only in the training group. To explore the neural substrates underlying these strategy effects, fMRI was used to measure brain activity in both groups during working memory task performance before and after an attention training period. In a comparison between pre- and post-training sessions, results showed increased activation in the anterior cingulate cortex (ACC). Relative to the control group, the post-training group exhibited increased activation in the left and right inferior parietal lobules (IPLs) and right superior parietal lobule (SPL). These findings suggest that use of a verbal to visual code switching strategy may assist older individuals in the maintenance of information in working memory.

  20. Visual Internal Urethrotomy for Adult Male Urethral Stricture Has Poor Long-Term Results

    PubMed Central

    Al Taweel, Waleed; Seyam, Raouf

    2015-01-01

    Objective. To determine the long-term stricture-free rate after visual internal urethrotomy following initial and follow-up urethrotomies. Methods. The records of all male patients who underwent direct visual internal urethrotomy for urethral stricture disease in our hospital between July 2004 and May 2012 were reviewed. The Kaplan-Meier method was used to analyze stricture-free probability after the first, second, third, fourth, and fifth urethrotomies. Results. A total of 301 patients were included. The overall stricture-free rate at the 36-month follow-up was 8.3% with a median time to recurrence of 10 months (95% CI of 9.5 to 10.5, range: 2–36). The stricture-free rate after one urethrotomy was 12.1% with a median time to recurrence of eight months (95% CI of 7.1–8.9). After the second urethrotomy, the stricture-free rate was 7.9% with a median time to recurrence of 10 months (95% CI of 9.3 to 10.6). After the third to fifth procedures, the stricture-free rate was 0%. There was no significant difference in the stricture-free rate between single and multiple procedures. Conclusion. The long-term stricture-free rate of visual internal urethrotomy is modest even after a single procedure. PMID:26494995

  1. Radarsat Geophysical Processor System: Data Products, Formats, and Visualization

    NASA Astrophysics Data System (ADS)

    Kerin, B. L.; Gens, R.; Baker, E.

    2003-12-01

    Radarsat Geophysical Processor System (RGPS) is designed to generate products that provide estimates of sea ice motion, deformation and sea ice thickness. The system uses Radarsat-1 ScanSAR Wide B (SWB) imagery acquired over the last six years over the entire Arctic Ocean. At the beginning of each winter season a regular grid with a default spacing of 10 km is initialized that defines the freeze up ice condition. With changing ice condition this regular grid distorts in shape and location. The distorted Langrangian grid is stored as an RGPS data product that reflects the ice condition at a particular time. In the past, RGPS products have been used to study processes operating at the scale of the entire Arctic Ocean. We are looking into the use of the RGPS data in a more refined grid, so that the product could also be used for studying smaller regions of interest. We have converted the specific binary format of the RGPS product to the more popular ARC/INFO polygon coverage format used by a wider research community. Finally, we have developed a visualization tool that will allow the user to drape the RGPS product containing ice attribute information over the corresponding synthetic aperture radar images and view a series of images showing change in ice condition over time.

  2. Gait variability in healthy old adults is more affected by a visual perturbation than by a cognitive or narrow step placement demand.

    PubMed

    Francis, Carrie A; Franz, Jason R; O'Connor, Shawn M; Thelen, Darryl G

    2015-09-01

    Gait variability measures have been linked to fall risk in older adults. However, challenging walking tasks may be required to elucidate increases in variability that arise from subtle age-related changes in cognitive processing and sensorimotor function. Hence, the study objective was to investigate the effects of visual perturbations, increased cognitive load, and narrowed step width on gait variability in healthy old and young adults. Eleven old (OA, 71.2±4.2 years) and twelve young (YA, 23.6±3.9 years) adults walked on a treadmill while watching a speed-matched virtual hallway. Subjects walked: (1) normally, (2) with mediolateral visual perturbations, (3) while performing a cognitive task (serial seven subtractions), and (4) with narrowed step width. We computed the mean and variability of step width (SW and SWV, respectively) and length (SL, SLV) over one 3-min trial per condition. Walking normally, old and young adults exhibited similar SWV and SLV. Visual perturbations significantly increased gait variability in old adults (by more than 100% for both SWV and SLV), but not young adults. The cognitive task and walking with narrowed step width did not show any effect on SWV or SLV in either group. The dramatic increase in step width variability when old adults were subjected to mediolateral visual perturbations was likely due to increased reliance on visual feedback for assessing whole-body position. Further work is needed to ascertain whether these findings may reflect sub-clinical balance deficits that could contribute to the increased fall risk seen with advancing age.

  3. Gait variability in healthy old adults is more affected by a visual perturbation than by a cognitive or narrow step placement demand

    PubMed Central

    Francis, Carrie A.; Franz, Jason R.; O'Connor, Shawn M.; Thelen, Darryl G.

    2015-01-01

    Gait variability measures have been linked to fall risk in older adults. However, challenging walking tasks may be required to elucidate increases in variability that arise from subtle age-related changes in cognitive processing and sensorimotor function. Hence, the study objective was to investigate the effects of visual perturbations, increased cognitive load, and narrowed step width on gait variability in healthy old and young adults. Eleven old (OA, 71.2 ± 4.2 years) and twelve young (YA, 23.6 ± 3.9 years) adults walked on a treadmill while watching a speed-matched virtual hallway. Subjects walked: 1) normally, 2) with mediolateral visual perturbations, 3) while performing a cognitive task (serial seven subtractions), and 4) with narrowed step width. We computed the mean and variability of step width (SW and SWV, respectively) and length (SL, SLV) over one three minute trial per condition. Walking normally, old and young adults exhibited similar SWV and SLV. Visual perturbations significantly increased gait variability in old adults (by more than 100% in both SWV and SLV), but not young adults. The cognitive task and walking with narrowed step width did not show any effect on SWV or SLV in either group. The dramatic increase in step width variability when old adults were subjected to mediolateral visual perturbations was likely due to increased reliance on visual feedback for assessing whole body position. Further work is needed to ascertain whether these findings may reflect sub-clinical balance deficits that could contribute to the increased fall risk seen with advancing age. PMID:26233581

  4. Impaired visual short-term memory capacity is distinctively associated with structural connectivity of the posterior thalamic radiation and the splenium of the corpus callosum in preterm-born adults.

    PubMed

    Menegaux, Aurore; Meng, Chun; Neitzel, Julia; Bäuml, Josef G; Müller, Hermann J; Bartmann, Peter; Wolke, Dieter; Wohlschläger, Afra M; Finke, Kathrin; Sorg, Christian

    2017-02-07

    Preterm birth is associated with an increased risk for lasting changes in both the cortico-thalamic system and attention; however, the link between cortico-thalamic and attention changes is as yet little understood. In preterm newborns, cortico-cortical and cortico-thalamic structural connectivity are distinctively altered, with increased local clustering for cortico-cortical and decreased integrity for cortico-thalamic connectivity. In preterm-born adults, among the various attention functions, visual short-term memory (vSTM) capacity is selectively impaired. We hypothesized distinct associations between vSTM capacity and the structural integrity of cortico-thalamic and cortico-cortical connections, respectively, in preterm-born adults. A whole-report paradigm of briefly presented letter arrays based on the computationally formalized Theory of Visual Attention (TVA) was used to quantify parameter vSTM capacity in 26 preterm- and 21 full-term-born adults. Fractional anisotropy (FA) of posterior thalamic radiations and the splenium of the corpus callosum obtained by diffusion tensor imaging were analyzed by tract-based spatial statistics and used as proxies for cortico-thalamic and cortico-cortical structural connectivity. The relationship between vSTM capacity and cortico-thalamic and cortico-cortical connectivity, respectively, was significantly modified by prematurity. In full-term-born adults, the higher FA in the right posterior thalamic radiation the higher vSTM capacity; in preterm-born adults this FA-vSTM-relationship was inversed. In the splenium, higher FA was correlated with higher vSTM capacity in preterm-born adults, whereas no significant relationship was evident in full-term-born adults. These results indicate distinct associations between cortico-thalamic and cortico-cortical integrity and vSTM capacity in preterm-and full-term-born adults. Data suggest compensatory cortico-cortical fiber re-organization for attention deficits after preterm delivery.

  5. Visual Neuroscience: Unique Neural System for Flight Stabilization in Hummingbirds.

    PubMed

    Ibbotson, M R

    2017-01-23

    The pretectal visual motion processing area in the hummingbird brain is unlike that in other birds: instead of emphasizing detection of horizontal movements, it codes for motion in all directions through 360°, possibly offering precise visual stability control during hovering.

  6. Hour-long adaptation in the awake early visual system.

    PubMed

    Stoelzel, Carl R; Huff, Joseph M; Bereshpolova, Yulia; Zhuang, Jun; Hei, Xiaojuan; Alonso, Jose-Manuel; Swadlow, Harvey A

    2015-08-01

    Sensory adaptation serves to adjust awake brains to changing environments on different time scales. However, adaptation has been studied traditionally under anesthesia and for short time periods. Here, we demonstrate in awake rabbits a novel type of sensory adaptation that persists for >1 h and acts on visual thalamocortical neurons and their synapses in the input layers of the visual cortex. Following prolonged visual stimulation (10-30 min), cells in the dorsal lateral geniculate nucleus (LGN) show a severe and prolonged reduction in spontaneous firing rate. This effect is bidirectional, and prolonged visually induced response suppression is followed by a prolonged increase in spontaneous activity. The reduction in thalamic spontaneous activity following prolonged visual activation is accompanied by increases in 1) response reliability, 2) signal detectability, and 3) the ratio of visual signal/spontaneous activity. In addition, following such prolonged activation of an LGN neuron, the monosynaptic currents generated by thalamic impulses in layer 4 of the primary visual cortex are enhanced. These results demonstrate that in awake brains, prolonged sensory stimulation can have a profound, long-lasting effect on the information conveyed by thalamocortical inputs to the visual cortex.

  7. The Lung Surfactant System in Adult Respiratory Distress Syndrome.

    DTIC Science & Technology

    1980-08-01

    STANDAROS- 193 A AD_ THE LUNG SURFACTANT SYSTEM IN ADULT RESPIRATORY DISTRESS SYNDROME FINAL PROGRESS REPORT John U. Balls August 1980 Sponsored by: US...D-A12l 434 THE LUNG SURFACTANT SYvTKl-OJL E~~rP DISTRESS SYNDROME (U) UNIVERSITY OF SOUTH FLORIDA TAMPA COLL OF MEDICINE J U BALIS RUG 8S DRNDi7-78-C...SURFACTANT SYSTEM IN ADULT Final 1 November 1978 - RESPIRATORY DISTU~SS SYNDROME - 30 April 1980 6. PERFORMING ORG. REPORT NUMBER * 7. AUTHOR(e) G. CONTRACT

  8. A General Provincial Situation Visualization System Based on iPhone Operating System of Shandong Province

    NASA Astrophysics Data System (ADS)

    Ye, Z.; Xiang, H.

    2014-04-01

    The paper discusses the basic principles and the problem solutions during the design and implementation of the mobile GIS system, and base on the research result, we developed the General Provincial Situation Visualization System Based on iOS of Shandong Province. The system is developed in the Objective-C programming language, and use the ArcGIS Runtime SDK for IOS as the development tool to call the "World-map Shandong" services to implement the development of the General Provincial Situation Visualization System Based on iOS devices. The system is currently available for download in the Appstore and is chosen as the typical application case of ESRI China ArcGIS API for iOS.

  9. Sex-dependent neurochemical effects of environmental enrichment in the visual system.

    PubMed

    Bessinis, D P; Dalla, C; Kokras, N; Pitychoutis, P M; Papadopoulou-Daifoti, Z

    2013-12-19

    Sex differences in the visual system have been reported in aspects of human vision, such as color perception, peripheral vision and even in the activation of the primary visual cortex. Similarly sex differences have been identified in the visual system of laboratory animals such as monkeys and rats. On the other hand, environmental enrichment (EE) has long been known to affect visual tissues. Taking into consideration the variation in the experimental approaches concerning EE and the sex differences in the visual system, we investigated in male and female rats the serotonergic and dopaminergic effects of EE in the retina and the visual cortex at different time points (i.e. P0-25, P0-P90 and P90-P150). Early EE in adulthood increased the serotonergic activity of the male visual cortex and the female retina (P0-P90). In addition early enrichment (P0-P90) increased dopaminergic activity in the female retina and in the visual cortex of both sexes. Late enrichment increased the serotonergic activity in the retina and visual cortex of both sexes (P90-P150), but increased the dopaminergic activity in the visual cortex only in male animals. In the present study we expose marked sex differences in the neurochemistry of visual tissues and we demonstrate for the first time that EE can in fact modify the serotonergic and dopaminergic neurotransmission in the retina and visual cortex. Overall, the present study underpins the sex-dependent neurochemical status of the visual system and provides insights into the different mechanisms underlying visual processing in the two sexes.

  10. Altered visual information processing systems in bipolar disorder: evidence from visual MMN and P3

    PubMed Central

    Maekawa, Toshihiko; Katsuki, Satomi; Kishimoto, Junji; Onitsuka, Toshiaki; Ogata, Katsuya; Yamasaki, Takao; Ueno, Takefumi; Tobimatsu, Shozo; Kanba, Shigenobu

    2013-01-01

    Objective: Mismatch negativity (MMN) and P3 are unique ERP components that provide objective indices of human cognitive functions such as short-term memory and prediction. Bipolar disorder (BD) is an endogenous psychiatric disorder characterized by extreme shifts in mood, energy, and ability to function socially. BD patients usually show cognitive dysfunction, and the goal of this study was to access their altered visual information processing via visual MMN (vMMN) and P3 using windmill pattern stimuli. Methods: Twenty patients with BD and 20 healthy controls matched for age, gender, and handedness participated in this study. Subjects were seated in front of a monitor and listened to a story via earphones. Two types of windmill patterns (standard and deviant) and white circle (target) stimuli were randomly presented on the monitor. All stimuli were presented in random order at 200-ms durations with an 800-ms inter-stimulus interval. Stimuli were presented at 80% (standard), 10% (deviant), and 10% (target) probabilities. The participants were instructed to attend to the story and press a button as soon as possible when the target stimuli were presented. Event-related potentials (ERPs) were recorded throughout the experiment using 128-channel EEG equipment. vMMN was obtained by subtracting standard from deviant stimuli responses, and P3 was evoked from the target stimulus. Results: Mean reaction times for target stimuli in the BD group were significantly higher than those in the control group. Additionally, mean vMMN-amplitudes and peak P3-amplitudes were significantly lower in the BD group than in controls. Conclusions: Abnormal vMMN and P3 in patients indicate a deficit of visual information processing in BD, which is consistent with their increased reaction time to visual target stimuli. Significance: Both bottom-up and top-down visual information processing are likely altered in BD. PMID:23898256

  11. From crypsis to mimicry: changes in colour and the configuration of the visual system during ontogenetic habitat transitions in a coral reef fish.

    PubMed

    Cortesi, Fabio; Musilová, Zuzana; Stieb, Sara M; Hart, Nathan S; Siebeck, Ulrike E; Cheney, Karen L; Salzburger, Walter; Marshall, N Justin

    2016-08-15

    Animals often change their habitat throughout ontogeny; yet, the triggers for habitat transitions and how these correlate with developmental changes - e.g. physiological, morphological and behavioural - remain largely unknown. Here, we investigated how ontogenetic changes in body coloration and of the visual system relate to habitat transitions in a coral reef fish. Adult dusky dottybacks, Pseudochromis fuscus, are aggressive mimics that change colour to imitate various fishes in their surroundings; however, little is known about the early life stages of this fish. Using a developmental time series in combination with the examination of wild-caught specimens, we revealed that dottybacks change colour twice during development: (i) nearly translucent cryptic pelagic larvae change to a grey camouflage coloration when settling on coral reefs; and (ii) juveniles change to mimic yellow- or brown-coloured fishes when reaching a size capable of consuming juvenile fish prey. Moreover, microspectrophotometric (MSP) and quantitative real-time PCR (qRT-PCR) experiments show developmental changes of the dottyback visual system, including the use of a novel adult-specific visual gene (RH2 opsin). This gene is likely to be co-expressed with other visual pigments to form broad spectral sensitivities that cover the medium-wavelength part of the visible spectrum. Surprisingly, the visual modifications precede changes in habitat and colour, possibly because dottybacks need to first acquire the appropriate visual performance before transitioning into novel life stages.

  12. Smart-system of distance learning of visually impaired people based on approaches of artificial intelligence

    NASA Astrophysics Data System (ADS)

    Samigulina, Galina A.; Shayakhmetova, Assem S.

    2016-11-01

    Research objective is the creation of intellectual innovative technology and information Smart-system of distance learning for visually impaired people. The organization of the available environment for receiving quality education for visually impaired people, their social adaptation in society are important and topical issues of modern education.The proposed Smart-system of distance learning for visually impaired people can significantly improve the efficiency and quality of education of this category of people. The scientific novelty of proposed Smart-system is using intelligent and statistical methods of processing multi-dimensional data, and taking into account psycho-physiological characteristics of perception and awareness learning information by visually impaired people.

  13. Effects of visual and motion simulation cueing systems on pilot performance during takeoffs with engine failures

    NASA Technical Reports Server (NTRS)

    Parris, B. L.; Cook, A. M.

    1978-01-01

    Data are presented that show the effects of visual and motion during cueing on pilot performance during takeoffs with engine failures. Four groups of USAF pilots flew a simulated KC-135 using four different cueing systems. The most basic of these systems was of the instrument-only type. Visual scene simulation and/or motion simulation was added to produce the other systems. Learning curves, mean performance, and subjective data are examined. The results show that the addition of visual cueing results in significant improvement in pilot performance, but the combined use of visual and motion cueing results in far better performance.

  14. The Effectiveness of External Bus Speaker Systems for Persons Who Are Visually Impaired.

    ERIC Educational Resources Information Center

    Wiener, William R.; Ponchillia, Paul; Joffee, Elga; Rutberg-Kuskin, Judith; Brown, John

    2000-01-01

    Two studies examined the effectiveness of external-speaker announcements in identifying incoming buses to 21 adults with visual impairments, including the placement of external speakers, the ability to understand simultaneous bus announcements, and the speech enhancement of announcements. Announcements could be heard above ambient traffic sounds…

  15. Valuation of active blind spot detection systems by younger and older adults.

    PubMed

    Souders, Dustin J; Best, Ryan; Charness, Neil

    2016-08-24

    Due to their disproportional representation in fatal crashes, younger and older drivers both stand to benefit from in-vehicle safety technologies, yet little is known about how they value such technologies, or their willingness to adopt them. The current study investigated older (aged 65 and greater; N=49) and younger (ages 18-23; N=40) adults' valuation of a blind spot monitor and asked if self-reported visual difficulties while driving predicted the amount participants were willing to pay for a particular system (BMW's Active Blind Spot Detection System) that was demonstrated using a short video. Large and small anchor values ($250 and $500, respectively) were used as between subjects manipulations to examine the effects of initial valuation, and participants proceeded through a short staircase procedure that offered them either the free installation of the system on their current vehicle or a monetary prize ($25-$950) that changed in value according to which option they had selected in the previous step of the staircase procedure. Willingness to use other advanced driver assistance systems (lane-departure warning, automatic lane centering, emergency braking, adaptive cruise control, and self-parking systems) was also analyzed, additionally controlling for prior familiarity of those systems. Results showed that increased age was associated with a higher valuation for the Active Blind Spot Detection System in both the large and small anchor value conditions controlling for income, gender, and technology self-efficacy. Older adults valued blind spot detection about twice as much ($762) as younger adults ($383) in the large anchor condition, though both groups' values were in the range for the current cost of an aftermarket system. Similarly, age was the most robust positive predictor of willingness to adopt other driving technologies, along with system familiarity. Difficulties with driving-related visual factors also positively predicting acceptance levels for

  16. Stepped-care to prevent depression and anxiety in visually impaired older adults – design of a randomised controlled trial

    PubMed Central

    2013-01-01

    Background Subthreshold depression and anxiety are common in the growing population of visually impaired older adults and increase the risk of full-blown depressive or anxiety disorders. Adequate treatment may prevent the development of depression or anxiety in this high risk group. Method/design A stepped-care programme was developed based on other effective interventions and focus groups with professionals and patient representatives of three low vision rehabilitation organisations in the Netherlands and Belgium. The final programme consists of four steps: 1) watchful waiting, 2) guided self-help, 3) problem solving treatment, 4) referral to general practitioner. The (cost-)effectiveness of this programme is evaluated in a randomised controlled trial. Patients (N = 230) are randomly assigned to either a treatment group (stepped-care) or a control group (usual care). The primary outcome is the incidence of depressive and anxiety disorders, measured with the Mini International Neuropsychiatric Interview (MINI). Discussion Preventive interventions for depression and anxiety have received little attention in the field of low vision. A stepped-care programme that focuses on both depression and anxiety has never been investigated in visually impaired older adults before. If the intervention is shown to be effective, this study will result in an evidence based treatment programme to prevent depression or anxiety in patients from low vision rehabilitation organisations. The pragmatic design of the study greatly enhances the generalisability of the results. However, a possible limitation is the difficulty to investigate the contribution of each individual step. Trial registration Identifier: NTR3296 PMID:23937975

  17. The distance of visual targets affects the spatial magnitude and multifractal scaling of standing body sway in younger and older adults.

    PubMed

    Munafo, Justin; Curry, Christopher; Wade, Michael G; Stoffregen, Thomas A

    2016-09-01

    The spatial magnitude of standing body sway is greater during viewing of more distant targets and reduced when viewing nearby targets. Classical interpretations of this effect are based on the projective geometry of changes in visual stimulation that are brought about by body sway. Such explanations do not motivate predictions about the temporal dynamics of body sway. We asked whether the distance of visible targets would affect both the spatial magnitude and the multifractality of standing body sway. It has been suggested that the multifractality of movement may change with age. Separately, previous research has not addressed the effects of target distance on postural sway in older adults. For these reasons, we crossed our variation in target distance with variation in age. In an open-air setting, we measured standing body sway in younger and older adults while looking at visual targets that were placed at three distances. The distance of visual targets affected the spatial magnitude of body sway in younger adults, replicating past studies. Target distance also affected the spatial magnitude of sway in older adults, confirming that this relation persists despite other age-related changes. Target distance also affected the multifractality of body sway, but this effect was modulated by age. Finally, the width of the multifractal spectrum was greater for older adults than for younger adults, revealing that healthy aging can affect the multifractality of movement. These findings reveal similarities and differences between the spatial magnitude and the multifractality of human movement.

  18. Testing geoscience data visualization systems for geological mapping and training

    NASA Astrophysics Data System (ADS)

    Head, J. W.; Huffman, J. N.; Forsberg, A. S.; Hurwitz, D. M.; Basilevsky, A. T.; Ivanov, M. A.; Dickson, J. L.; Senthil Kumar, P.

    2008-09-01

    Traditional methods of planetary geological mapping have relied on photographic hard copy and light-table tracing and mapping. In the last several decades this has given way to the availability and analysis of multiple digital data sets, and programs and platforms that permit the viewing and manipulation of multiple annotated layers of relevant information. This has revolutionized the ability to incorporate important new data into the planetary mapping process at all scales. Information on these developments and approaches can be obtained at http://astrogeology.usgs. gov/ Technology/. The processes is aided by Geographic Information Systems (GIS) (see http://astrogeology. usgs.gov/Technology/) and excellent analysis packages (such as ArcGIS) that permit co-registration, rapid viewing, and analysis of multiple data sets on desktop displays (see http://astrogeology.usgs.gov/Projects/ webgis/). We are currently investigating new technological developments in computer visualization and analysis in order to assess their importance and utility in planetary geological analysis and mapping. Last year we reported on the range of technologies available and on our application of these to various problems in planetary mapping. In this contribution we focus on the application of these techniques and tools to Venus geological mapping at the 1:5M quadrangle scale. In our current Venus mapping projects we have utilized and tested the various platforms to understand their capabilities and assess their usefulness in defining units, establishing stratigraphic relationships, mapping structures, reaching consensus on interpretations and producing map products. We are specifically assessing how computer visualization display qualities (e.g., level of immersion, stereoscopic vs. monoscopic viewing, field of view, large vs. small display size, etc.) influence performance on scientific analysis and geological mapping. We have been exploring four different environments: 1) conventional

  19. Thoracic ROM measurement system with visual bio-feedback: system design and biofeedback evaluation.

    PubMed

    Ando, Takeshi; Kawamura, Kazuya; Fujitani, Junko; Koike, Tomokazu; Fujimoto, Masashi; Fujie, Masakatsu G

    2011-01-01

    Patients with diseases such as chronic obstructive pulmonary disease (COPD) need to improve their thorax mobility. Thoracic ROM is one of the simplest and most useful indexes to evaluate the respiratory function. In this paper, we have proposed the prototype of a simple thoracic ROM measurement system with real-time visual bio-feedback in the chest expansion test. In this system, the thoracic ROM is measured using a wire-type linear encoder whose wire is wrapped around the thorax. In this paper, firstly, the repeatability and reliability of measured thoracic ROM was confirmed as a first report of the developed prototype. Secondly, we analyzed the effect of the bio-feedback system on the respiratory function. The result of the experiment showed that it was easier to maintain a large and stable thoracic ROM during deep breathing by using the real-time visual biofeedback system of the thoracic ROM.

  20. Lexical decisions in adults with low and high susceptibility to pattern-related visual stress: a preliminary investigation

    PubMed Central

    Gilchrist, James M.; Allen, Peter M.

    2015-01-01

    Pattern-related visual stress (PRVS) is a form of sensory hypersensitivity that some people experience when viewing high contrast repeating patterns, notably alternating dark and light stripes. Those susceptible to PRVS typically have a strong aversion to such stimuli, and this is often accompanied by experiences of visual discomfort and disturbance. The patterns most likely to elicit symptoms of PRVS have a square-wave grating configuration of spatial frequency ~3 cycles/degree. Such stimuli are characteristic of printed text in which lines of words and the spaces between them present a high contrast grating-like stimulus. Consequently, much printed reading material has the potential to elicit PRVS that may impair reading performance, and this problem appears to be common in individuals with reading difficulties including dyslexia. However, the manner in which PRVS affects reading ability is unknown. One possibility is that the early sensory visual stress may interfere with the later cognitive word recognition stage of the reading process, resulting in reading performance that is slower and/or less accurate. To explore the association of PRVS with word recognition ability, lexical decision performance (speed and accuracy) to words and pronounceable non-words was measured in two groups of adults, having low and high susceptibility to PRVS. Results showed that lexical decisions were generally faster but less accurate in high-PRVS, and also that high-PRVS participants made decisions significantly faster for words than for non-words, revealing a strong lexicality effect that was not present in low-PRVS. These findings are novel and, as yet, unconfirmed by other studies. PMID:25926810

  1. [Role of gravitation-dependent systems in visual tracing].

    PubMed

    Kornilova, L N

    2003-03-01

    In 31 astronauts under conditions of free falling, when the visual functions proper were preserved, the precision and speedy parameters of all the forms of visual tracing (saccades, smooth tracing) became worse, and in a number of cases a complete disintegration of the smooth tracing reflex occurred as well as a 2-fold and greater enhancement of the time for fixing the stare at a target. In the beginning of adaptation to altered gravitation conditions, a transition of the smooth visual tracing into the strategy of saccadic approximation, occurs. These disorders were shown to be due to a vestibular deprivation.

  2. Subcellular Topography of Visually Driven Dendritic Activity in the Vertebrate Visual System

    PubMed Central

    Bollmann, Johann H.; Engert, Florian

    2010-01-01

    SUMMARY Neural pathways projecting from sensory organs to higher brain centers form topographic maps in which neighbor relationships are preserved from a sending to a receiving neural population. Sensory input can generate compartmentalized electrical and biochemical activity in the dendrites of a receiving neuron. Here, we show that in the developing retinotectal projection of young Xenopus tadpoles, visually driven Ca2+ signals are topographically organized at the subcellular, dendritic scale. Functional in vivo two-photon Ca2+ imaging revealed that the sensitivity of dendritic Ca2+ signals to stimulus location in visual space is correlated with their anatomical position within the dendritic tree of individual neurons. This topographic distribution was dependent on NMDAR activation, whereas global Ca2+ signals were mediated by Ca2+ influx through dendritic, voltage-dependent Ca2+ channels. These findings suggest a framework for plasticity models that invoke local dendritic Ca2+ signaling in the elaboration of neural connectivity and dendrite-specific information storage. PMID:19323998

  3. Real-time unconstrained object recognition: a processing pipeline based on the mammalian visual system.

    PubMed

    Aguilar, Mario; Peot, Mark A; Zhou, Jiangying; Simons, Stephen; Liao, Yuwei; Metwalli, Nader; Anderson, Mark B

    2012-03-01

    The mammalian visual system is still the gold standard for recognition accuracy, flexibility, efficiency, and speed. Ongoing advances in our understanding of function and mechanisms in the visual system can now be leveraged to pursue the design of computer vision architectures that will revolutionize the state of the art in computer vision.

  4. [Analytical model of readaptation of the human visual system after light exposure].

    PubMed

    Naumov, N D

    2003-01-01

    The process of readaptation of the human visual system is considered as the behavior of a follow-up system, with the brightness of the background being the control signal. The times of recovery of visual acuity calculated by the model are compared with the experimental data.

  5. Muscle tension induced after learning enhances long-term narrative and visual memory in healthy older adults.

    PubMed

    Nielson, Kristy A; Wulff, Laura L; Arentsen, Timothy J

    2014-03-01

    Arousing events are better remembered than mundane events. Indeed, manipulation of arousal, such as by muscle tension, can influence memory even when it occurs shortly after learning. Indeed, our founding study showed this approach can raise delayed memory performance in older adults to a level comparable to that of unaided young adults. Yet, systematic studies, especially those investigating different modalities or types of memory, have not been done. This study investigated the effects of a brief bout of isometric exercise via handgrip on narrative and visuospatial episodic memory in healthy elders. Forty-seven participants completed the Logical Memory subtest of the Wechsler Memory Scales III (LM) and the Benton Visual Retention Test (BVRT), followed alternately by no treatment and by moderately squeezing a sand-filled latex ball for 1-min (counterbalanced order and test forms). Isometric exercise significantly increased both positive and negative affect ratings. Retention was tested 2 weeks later. Delayed recall and recognition of LM was enhanced by arousal relative to control, as was recognition of the BVRT. The results extend past findings that muscle tension induced after learning modulates memory consolidation, extending findings in elders to suggest that a simple form of isometric exercise can have practical effects, such as aiding memory for stories and images.

  6. A Unified Air-Sea Visualization System: Survey on Gridding Structures

    NASA Technical Reports Server (NTRS)

    Anand, Harsh; Moorhead, Robert

    1995-01-01

    The goal is to develop a Unified Air-Sea Visualization System (UASVS) to enable the rapid fusion of observational, archival, and model data for verification and analysis. To design and develop UASVS, modelers were polled to determine the gridding structures and visualization systems used, and their needs with respect to visual analysis. A basic UASVS requirement is to allow a modeler to explore multiple data sets within a single environment, or to interpolate multiple datasets onto one unified grid. From this survey, the UASVS should be able to visualize 3D scalar/vector fields; render isosurfaces; visualize arbitrary slices of the 3D data; visualize data defined on spectral element grids with the minimum number of interpolation stages; render contours; produce 3D vector plots and streamlines; provide unified visualization of satellite images, observations and model output overlays; display the visualization on a projection of the users choice; implement functions so the user can derive diagnostic values; animate the data to see the time-evolution; animate ocean and atmosphere at different rates; store the record of cursor movement, smooth the path, and animate a window around the moving path; repeatedly start and stop the visual time-stepping; generate VHS tape animations; work on a variety of workstations; and allow visualization across clusters of workstations and scalable high performance computer systems.

  7. A Systems Model for Operating an Adult Training Program

    ERIC Educational Resources Information Center

    Leslie, William; Dimitrick, Adam

    1977-01-01

    A description of the uses and application of a model for designing a machine operator adult training program based on Silvern's systems approach (anasynthesis). The DACUM (Developing A Curriculum) process was used in developing the curriculum. The DACUM chart showing the terminal objectives is included. (EM)

  8. Instructional Videos for Supporting Older Adults Who Use Interactive Systems

    ERIC Educational Resources Information Center

    Gramss, Denise; Struve, Doreen

    2009-01-01

    The study reported in this paper investigated the usefulness of different instructions for guiding inexperienced older adults through interactive systems. It was designed to compare different media in relation to their social as well as their motivational impact on the elderly during the learning process. Precisely, the video was compared with…

  9. Facilitation and inhibition in the visual system after photic stimulation.

    NASA Technical Reports Server (NTRS)

    Cavaggioni, A.; Goldstein, M. H., Jr.

    1965-01-01

    Changes in shock-evoked response complex /SERC/ RECORDED from visual cortexes of cats after retinal illumination, noting enhancement of waveform after photic stimulation and role of barbiturate anesthetization

  10. Literacy breaks mirror invariance for visual stimuli: a behavioral study with adult illiterates.

    PubMed

    Pegado, Felipe; Nakamura, Kimihiro; Braga, Lucia W; Ventura, Paulo; Nunes Filho, Gilberto; Pallier, Christophe; Jobert, Antoinette; Morais, José; Cohen, Laurent; Kolinsky, Régine; Dehaene, Stanislas

    2014-04-01

    The ability to recognize 2 mirror images as the same picture across left-right inversions exists early on in humans and other primates. In order to learn to read, however, one must discriminate the left-right orientation of letters and distinguish, for instance, b from d. We therefore reasoned that literacy may entail a loss of mirror invariance. To evaluate this hypothesis, we asked adult literates, illiterates, and ex-illiterates to perform a speeded same-different task with letter strings, false fonts, and pictures regardless of their orientation (i.e., they had to respond "same" to mirror pairs such as "iblo oldi"). Literates presented clear difficulties with mirror invariance. This "mirror cost" effect was strongest with letter strings, but crucially, it was also observed with false fonts and even with pictures. In contrast, illiterates did not present any cost for mirror pairs. Interestingly, subjects who learned to read as adults also exhibited a mirror cost, suggesting that modest reading practice, late in life, can suffice to break mirror invariance.

  11. Impaired recollection of visual scene details in adults with autism spectrum conditions.

    PubMed

    Cooper, Rose A; Plaisted-Grant, Kate C; Hannula, Deborah E; Ranganath, Charan; Baron-Cohen, Simon; Simons, Jon S

    2015-08-01

    Subtle memory deficits observed in autism spectrum conditions (ASC) have often been characterized as reflecting impaired recollection and it has been proposed that a relational binding deficit may underlie the recollection impairment. However, subjective recollection and relational binding have not been measured within the same task in ASC to date and it is unclear whether a relational binding deficit can provide a full account of recollection impairments in ASC. Relational memory has also not been compared with item memory when the demands of the 2 tasks are comparable. To assess recollection, relational memory, and item memory within a single task in ASC, 24 adults with ASC and 24 typically developed adults undertook a change detection memory task that assessed recollection of item-specific and spatial details. Participants studied rendered indoor and outdoor scenes and, in a subsequent recognition memory test, distinguished scenes that had not changed from those that had either undergone an item change (a different item exemplar) or a relational (spatial) change, which was followed by a subjective recollection judgment. The ASC group identified fewer item changes and spatial changes, to a similar degree, which was attributable to a specific reduction in recollection-based recognition relative to the control group. These findings provide evidence that recollection deficits in ASC may not be driven entirely by a relational binding deficit.

  12. Acquisition of Visual Perception in Blind Adults Using the BrainPort Artificial Vision Device

    PubMed Central

    Pintar, Christine; Arnoldussen, Aimee; Fisher, Christopher

    2015-01-01

    OBJECTIVE. We sought to determine whether intensive low vision rehabilitation would confer any functional improvement in a sample of blind adults using the BrainPort artificial vision device. METHOD. Eighteen adults ages 28–69 yr (n = 10 men and n = 8 women) who had light perception only or worse vision bilaterally spent up to 6 hr per day for 1 wk undergoing structured rehabilitation interventions. The functional outcomes of object identification and word recognition were tested at baseline and after rehabilitation training. RESULTS. At baseline, participants were unable to complete the two functional assessments. After participation in the 1-wk training protocol, participants were able to use the BrainPort device to complete the two tasks with moderate success. CONCLUSION. Without training, participants were not able to perform above chance level using the BrainPort device. As artificial vision technologies become available, occupational therapy practitioners can play a key role in clients’ success or failure in using these devices. PMID:25553750

  13. System Design for On-line Distributed Computational Visualization and Steering

    SciTech Connect

    Wu, Qishi; Zhu, Mengxia; Rao, Nageswara S

    2006-01-01

    We propose a distributed computing framework for network-optimized visualization and steering of real-time scientific simulations and computations executed on a remote host, such as workstation, cluster or supercomputer. Unlike the conventional "batch" simulations, this system enables: (i) monitoring of an ongoing remote computation using visualization tools, and (ii) on-line specification of simulation parameters to interactively steer remote computations. Using performance models for transport channels and visualization modules, we develop a dynamic programming method to optimize the realization of the visualization pipeline over a wide-area network to maximize the frame rate. We present experimental results to illustrate the effectiveness of this system.

  14. elVis: An Interactive System For Visualization of Unsteady Fluid Flow

    NASA Technical Reports Server (NTRS)

    Gerald-Yamasaki, Michael; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    ElVis is a prototype system with allows for the interactive visualization of unsteady fluid flow. The increasing computational power applied to fluid dynamics simulations presents the enormous challenge to the visualization system designer to apply a wide range of technologies to the analysis process with ever increasing demands on performance. Visualization of the results of unsteady fluid flow simulations presents the challenge of exploring very large and complex data sets. Since exploration is a trial and error process, it is of utmost importance that the time required to execute a trial (i.e., create a visualization) be at a minimum in order to provide real time interaction.

  15. Visual Analytics of integrated Data Systems for Space Weather Purposes

    NASA Astrophysics Data System (ADS)

    Rosa, Reinaldo; Veronese, Thalita; Giovani, Paulo

    Analysis of information from multiple data sources obtained through high resolution instrumental measurements has become a fundamental task in all scientific areas. The development of expert methods able to treat such multi-source data systems, with both large variability and measurement extension, is a key for studying complex scientific phenomena, especially those related to systemic analysis in space and environmental sciences. In this talk, we present a time series generalization introducing the concept of generalized numerical lattice, which represents a discrete sequence of temporal measures for a given variable. In this novel representation approach each generalized numerical lattice brings post-analytical data information. We define a generalized numerical lattice as a set of three parameters representing the following data properties: dimensionality, size and post-analytical measure (e.g., the autocorrelation, Hurst exponent, etc)[1]. From this representation generalization, any multi-source database can be reduced to a closed set of classified time series in spatiotemporal generalized dimensions. As a case study, we show a preliminary application in space science data, highlighting the possibility of a real time analysis expert system. In this particular application, we have selected and analyzed, using detrended fluctuation analysis (DFA), several decimetric solar bursts associated to X flare-classes. The association with geomagnetic activity is also reported. DFA method is performed in the framework of a radio burst automatic monitoring system. Our results may characterize the variability pattern evolution, computing the DFA scaling exponent, scanning the time series by a short windowing before the extreme event [2]. For the first time, the application of systematic fluctuation analysis for space weather purposes is presented. The prototype for visual analytics is implemented in a Compute Unified Device Architecture (CUDA) by using the K20 Nvidia

  16. Visual Impairment among Older Adults in a Rural Community in Eastern China

    PubMed Central

    Qian, Deng-Juan; Sun, Hong-Peng; Ma, Qinghua; Xu, Yong

    2016-01-01

    Purpose. To determine the prevalence, causes, and associations of visual impairment (VI) among participants aged 60 years or older in a rural community in China. Methods. A community-based survey was undertaken in a rural town located in Eastern China and 4579 people aged 60 years or older participated in the study. Presenting visual acuity was assessed using a Snellen chart with tumbling-E optotypes and anterior segment was examined using a slit-lamp. VI was defined as presenting VA <6/18 and it included moderate VI (<6/18 to 6/60) and blindness (<6/60). Results. The prevalence of VI was 5.4% (95% confidence interval [CI] 4.7–6.0). In multivariate analysis, the presence of VI was positively associated with increasing age (odds ratio [OR] = 1.12, 95% CI 1.10–1.16, per year increase), female gender (OR = 2.33, 95% CI 1.53–3.55), the presence of hypertension (OR = 1.31, 95% CI 1.001–1.85), living alone (OR = 1.52, 95% CI 1.08–2.62), and increased sleeping hours (OR = 1.10, 95% CI 1.001–1.22). Drinking 3 or more glasses of green tea per day was inversely associated with VI (OR = 0.79, 95% CI 0.63–0.98). Conclusion. VI was less prevalent in this community compared with previous report in other areas in China. PMID:27777793

  17. Implementation of an Evidence-Based Guideline for the Referral of Adults Who Are Visually Impaired in the Netherlands: Potential Barriers

    ERIC Educational Resources Information Center

    Cruysberg, Juliette K.; van Rens, Ger H. M. B.

    2007-01-01

    This article reports on a study on the implementation of an evidence-based guideline for the referral for rehabilitation of adults who are visually impaired in the Netherlands. The purpose of the study was to find out if there are potential barriers to the implementation of the Nederlands Oogheelkundig Gezelschap (NOG) (2004) evidence-based…

  18. H3 and H4 Lysine Acetylation Correlates with Developmental and Experimentally Induced Adult Experience-Dependent Plasticity in the Mouse Visual Cortex

    PubMed Central

    Vierci, Gabriela; Pannunzio, Bruno; Bornia, Natalia; Rossi, Francesco M.

    2016-01-01

    Histone posttranslational modifications play a fundamental role in orchestrating gene expression. In this work, we analyzed the acetylation of H3 and H4 histones (AcH3–AcH4) and its modulation by visual experience in the mouse visual cortex (VC) during normal development and in two experimental conditions that restore juvenile-like plasticity levels in adults (fluoxetine treatment and enriched environment). We found that AcH3–AcH4 declines with age and is upregulated by treatments restoring plasticity in the adult. We also found that visual experience modulates AcH3–AcH4 in young and adult plasticity-restored mice but not in untreated ones. Finally, we showed that the transporter vGAT is downregulated in adult plasticity-restored models. In summary, we identified a dynamic regulation of AcH3–AcH4, which is associated with high plasticity levels and enhanced by visual experience. These data, along with recent ones, indicate H3–H4 acetylation as a central hub in the control of experience-dependent plasticity in the VC. PMID:27891053

  19. Complementary and dynamic type II cadherin expression associated with development of the primate visual system.

    PubMed

    Matsunaga, Eiji; Nambu, Sanae; Oka, Mariko; Iriki, Atsushi

    2014-10-01

    The middle temporal visual area (MT, also known as V5) is a visual association area that is particularly evolved in the primate brain. The MT receives input from the primary visual area (V1), constitutes part of the dorsal visual pathway, and plays an essential role in processing motion. Connections between the MT and V1 in the primate brain are formed after birth, and are related to the maturation of visual system. However, it remains to be determined what molecular mechanisms control the formation and maturation of the visual system. Cadherins are transmembrane proteins, originally isolated as cell adhesion molecules, which have multiple roles in synapse formation and function. To investigate potential involvement of cadherins in development of the primate visual system, we examined type II cadherin expression (cadherin-6, -8, -12) in cortical and thalamic visual areas of pre- and postnatal brains of the common marmoset (Callithrix jacchus). In the prenatal brain, cadherin-6 was dominantly expressed in the pulvino-MT pathway whereas cadherin-8 was dominant in the lateral geniculate nucleus (LGN)-V1 pathway. During postnatal development, there was a downregulation of cadherin-6 and upregulation of cadherin-8 expression in the MT. The timing of this cadherin exchange preceded the development of V1-MT connections. Our results suggest the possibility that changes in cadherin expression are involved in the development of the primate visual system, and that a switch in cadherin expression may be a general mechanism to control neural plasticity of highly cognitive abilities.

  20. Impulse processing: A dynamical systems model of incremental eye movements in the visual world paradigm

    PubMed Central

    Kukona, Anuenue; Tabor, Whitney

    2011-01-01

    The visual world paradigm presents listeners with a challenging problem: they must integrate two disparate signals, the spoken language and the visual context, in support of action (e.g., complex movements of the eyes across a scene). We present Impulse Processing, a dynamical systems approach to incremental eye movements in the visual world that suggests a framework for integrating language, vision, and action generally. Our approach assumes that impulses driven by the language and the visual context impinge minutely on a dynamical landscape of attractors corresponding to the potential eye-movement behaviors of the system. We test three unique predictions of our approach in an empirical study in the visual world paradigm, and describe an implementation in an artificial neural network. We discuss the Impulse Processing framework in relation to other models of the visual world paradigm. PMID:21609355