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PubMed2005

Artificial human vision.

Can vision be restored to the blind? As early as 1929 it was discovered that stimulating the visual cortex of an individual led to the perception of spots of light, known as phosphenes [1] . The aim of artificial human vision systems is to attempt to utilize the perception of phosphenes to provide a useful substitute for normal vision. Currently, four locations for electrical stimulation are being investigated; behind the retina (subretinal), in front of the retina (epiretinal), the optic nerve and the visual cortex (using intra- and surface electrodes). This review discusses artificial human vision technology and requirements, and reviews the current development projects.

Artificial Intelligence↗
PubMed1982

Influence of vision on haptic encoding processes.

Sighted subjects (n = 15) assembled 6-piece jigsaw puzzles under four conditions of visual-haptic perception which both separated these perceptual systems and required the simultaneous use of vision and touch. The time required and haptic scanning strategies used to assemble the puzzles in each of the four conditions were examined to determine the influence of type of visual involvement upon haptic encoding processes and the degree to which the visual and haptic systems are linked. Results indicate that a cognitive component is involved during visual-tactual form perception which affects how the perceptual modalities work together and how information is selected, encoded, and processed. When vision and touch were used simultaneously to examine the same stimulus, and visual information was adequate for responding, vision dominated touch. However, in conditions of visual-haptic perception in which visual input was inadequate for responding or when haptic perception was independent of vision, subjects relied upon a form of information which was specifically tactual in nature and independent of visual or verbal recoding.

Discrimination Learning↗
PubMed1995

Effects of occluded vision and imagery on putting golf balls.

This study examined the effects of combining occluded vision with imagery for acquiring and retaining golf-putting skill in a college class of 80. The findings indicated that college students who registered for beginning golf classes were significantly higher in putting-skill acquisition using occluded vision and visual imagery than practicing while in visual contact with the ball and no imagery. Occluded-vision imagery was not superior to visual imagery for acquisition or retention of putting skill. In addition, the occluded-vision subjects showed positive transfer to visual putting skills.

Adolescent↗
PubMedDate not supplied

Use of market segmentation to identify untapped consumer needs in vision correction surgery for future growth.

PURPOSE: Market segmentation analysis identifies discrete segments of the population whose beliefs are consistent with exhibited behaviors such as purchase choice. This study applies market segmentation analysis to low myopes (-1 to -3 D with less than 1 D cylinder) in their consideration and choice of a refractive surgery procedure to discover opportunities within the market. METHOD: A quantitative survey based on focus group research was sent to a demographically balanced sample of myopes using contact lenses and/or glasses. A variable reduction process followed by a clustering analysis was used to discover discrete belief-based segments. The resulting segments were validated both analytically and through in-market testing. RESULTS: Discontented individuals who wear contact lenses are the primary target for vision correction surgery. However, 81% of the target group is apprehensive about laser in situ keratomileusis (LASIK). They are nervous about the procedure and strongly desire reversibility and exchangeability. CONCLUSION: There exists a large untapped opportunity for vision correction surgery within the low myope population. Market segmentation analysis helped determine how to best meet this opportunity through repositioning existing procedures or developing new vision correction technology, and could also be applied to identify opportunities in other vision correction populations.

Adult↗
PubMedDate not supplied

Reclaiming the vision of reaching for heart as well as hands.

Although infrequently discussed in the professional literature, visionary language and visual imagery are identifiable elements within occupational therapy's culture. They seem part of the profession's desire to characterize, affirm, and renew itself. One early vision of practice, that of reaching for heart as well as hands, is the subject of this inquiry that extends a prior discussion of visions in occupational therapy. Central to the inquiry are the early vision's (a) origin, exemplification, and clarity of meaning within one autobiographical text and (b) merits for the profession's characterization, affirmation, and renewal. The early vision of reaching for heart as well as hands may benefit the profession today by characterizing the ethos of occupational therapy as integrative, affirming its practice as occupational, and inspiring its practitioners to renew a commitment to caring.

Attitude of Health Personnel↗
PubMed1995

Values and value--a vision for the Australian health care system.

The Australian health care system is at a crossroads. Status quo is not a sustainable option for the future. Rising consumption, spiralling costs, the decline of private health insurance and a public sector 'bursting at the seams' threaten our traditional values of a universal, affordable, accessible, equitable, high-quality system. As a result, we believe that major reform of the health care system is both necessary and inevitable in order to ensure that the values of the system are maintained and to extract maximum value from limited health resources. In this article we lay out our vision for the Australian health care system. It is a vision characterised by transformational change--shifting of risk from patients and taxpayers to providers, downsizing of acute care capacity, integration of services across the system, rationalisation of State and Federal responsibilities and a 'shakeout' of providers and insurers resulting from intensified, but bounded, competition. We believe that the direction for health care players needs to be clarified so that, as a country, we can continue to have a best practice model of health care delivery. We present this vision as a 'stake in the ground' to set parameters around which this debate can emerge. It may be provocative and challenging, but it is our vision into the future.

Australia↗
PubMed1997

1996 Andrew Pattullo lecture. A vision of the role of health administration education in the transformation of the American health system.

In summary, it is my conviction that each of the AUPHA programs would be well advised to re-discover a shared vision of health care as public service, caring for communities as well as for patients and enrolled populations. I am also convinced that each program should be shaping a shared vision of the role of the academic program in providing intellectual leadership in this respect. These processes can be designed to have impact on all of the activities of the program, starting with low hanging fruit, and moving higher with growing confidence and commitment. The key task for AUPHA as an organization right now is ro re-examine its own vision as a basis for providing strong leadership to the field. This involves promoting visioning as a management tool, helping to sharpen the accreditation requirements in this respect, and carrying out the recommendation of the Pew Health Professions Commission to bring the academic and practitioner worlds into closer synch. The talent and the zeal are evident. What is required now is the will to make changes. Continued transformation of the American Health system and of the academic programs in health administration are both inevitable. Managing the transformation is more exciting, more productive, more professionally satisfying and more fun than just surviving or not surviving at all. Managing a transformation is not easy, especially in academia. Just watching it happen is not nearly as satisfying or as much fun.

Consumer Advocacy↗
PubMed1998

Creating a vision for your medical call center.

MCC technologies and applications that can have a positive impact on managed care delivery are almost limitless. As you determine your vision, be sure to have in mind the following questions: (1) Do you simply want an efficient front end for receiving calls? (2) Do you want to offer triage services? (3) Is your organization ready for a fully functional "electronic physician's office?" Understand your organization's strategy. Where are you going, not only today but five years from now? That information is essential to determine your vision. Once established, your vision will help determine what you need and whether you should build or outsource. Vendors will assist in cost/benefit analysis of their equipment, but do not lose sight of internal factors such as "prior inclination" costs in the case of a nurse triage program. The technology is available to take your vision to its outer reaches. With the projected increase in utilization of call center services, don't let your organization be left behind!

Computer Communication Networks↗
PubMed1999

[Phantom vision phenomenon].

The subject of the paper is the phenomenon of phantom vision. It occurs among the blind (or almost blind) and is characterised by perceiving various visual sensations, for example: light, geometrical shapes, buildings, people, flowers etc. The paper presents views explaining the generation of phantom vision. According to Melzack's theory, the occurrence of these sensations is explained in relation to the phenomenon of transforming the neuro-activity of the brain in a specific--for each organ--neuronal network called neuromatrix. Even if some organs do exist but have ceased to function completely (or to a significant degree) and consequently the brain does not receive any sensory stimuli from them, the neuromatrix in brain can generate visual sensations constituting the phantom vision phenomenon. The paper also presents three cases of phantom vision.

Aged↗
PubMed2001

Surveying the seen: 100 years of British vision.

Perceptual phenomena and their interpretations have fashioned the course of psychology. This article surveys how theories of visual perception and methodologies have developed during the lifetime of the British Psychological Society. The experimental study of vision was instigated by British natural philosophers in the early nineteenth century but this impetus was not maintained thereafter. Not until the 1930s and 1940s did research on perception resume in earnest within British universities. The adoption of concepts (such as schema) potentially grounded in neural organization, particularly by Bartlett and Craik, accelerated experimental, theoretical and applied vision research. From mid-century the influence of information processing models of perception became increasingly dominant, and they were often integrated with the rapidly expanding understanding of neurophysiological underpinnings. The epitome of these developments was Marr's model of vision which, in our view, marked the start of the modern era of vision research. Computers have transformed the nature of stimulus control and response measurement in perceptual experiments. More naturalistic stimuli can be presented and manipulated, and complex behavioural responses, such as patterns of eye movements, fractionated. Non-invasive recording of brain activity to visual stimulation has similarly been transformed with a variety of methods for imaging brain activity. Neuroimaging has been applied to localizing perceptual and cognitive functions and in studying patients with known deficits in visual recognition. However, the eagerness with which the computer has been adopted by perceptual psychologists is likely to be tempered by a growing awareness of the differences between viewing scenes and simulations of them.

Brain↗
PubMed2001

The power of a vision. The nurse's journey through health care.

1. Currently, health care is a constant battle between cost and compassion. The most difficult change health care professionals have had to make is expanding the vision of the compassionate caregiver to include the bottom line business professional. 2. Occupational and environmental health nurses need to have more visibility in the companies they work for to get a "seat at the table" with the rest of the management team. One way to gain visibility and credibility is to be a part of the community newsletter via a column "Ask the Nurse" where employees send in questions and nurses answer one or two questions each month. 3. Occupational and environmental health nurses can become the "visionaries" of the companies they work for by formulating a vision of what they want to provide for the employees of their companies and passionately sharing that vision with management and employees alike. If both management and employees buy into that vision, a remarkable transition can take place. 4. The future is very exciting for occupational and environmental health nurses. For those leaving the corporate world, there will be expanding opportunities in research, education, policy making, and lobbying. Occupational and environmental health nurses with the entrepeneurial spirit could consider being a consultant, working for a number of different companies, both here and abroad.

Career Mobility↗
PubMed2001

Surveying the seen: 100 years of British vision.

Perceptual phenomena and their interpretations have fashioned the course of psychology. This article surveys how theories of visual perception and methodologies have developed during the lifetime of the British Psychological Society. The experimental study of vision was instigated by British natural philosophers in the early nineteenth century but this impetus was not maintained thereafter. Not until the 1930s and 1940s did research on perception resume in earnest within British universities. The adoption of concepts (such as schema) potentially grounded in neural organization, particularly by Bartlett and Craik, accelerated experimental, theoretical and applied vision research. From mid-century the influence of information processing models of perception became increasingly dominant, and they were often integrated with the rapidly expanding understanding of neurophysiological underpinnings. The epitome of these developments was Marr's model of vision which, in our view, marked the start of the modern era of vision research. Computers have transformed the nature of stimulus control and response measurement in perceptual experiments. More naturalistic stimuli can be presented and manipulated, and complex behavioural responses, such as patterns of eye movements, fractionated. Non-invasive recording of brain activity to visual stimulation has similarly been transformed with a variety of methods for imaging brain activity. Neuroimaging has been applied to localizing perceptual and cognitive functions and in studying patients with known deficits in visual recognition. However, the eagerness with which the computer has been adopted by perceptual psychologists is likely to be tempered by a growing awareness of the differences between viewing scenes and simulations of them.

Journal Article↗
PubMed2002

Biologically based machine vision: signal analysis of monopolar cells in the visual system of Musca domestica.

Machine vision for navigational purposes is a rapidly growing field. Many abilities such as object recognition and target tracking rely on vision. Autonomous vehicles must be able to navigate in dynamic enviroments and simultaneously locate a target position. Traditional machine vision often fails to react in real time because of large computational requirements whereas the fly achieves complex orientation and navigation with a relatively small and simple brain. Understanding how the fly extracts visual information and how neurons encode and process information could lead us to a new approach for machine vision applications. Photoreceptors in the Musca domestica eye that share the same spatial information converge into a structure called the cartridge. The cartridge consists of the photoreceptor axon terminals and monopolar cells L1, L2, and L4. It is thought that L1 and L2 cells encode edge related information relative to a single cartridge. These cells are thought to be equivalent to vertebrate bipolar cells, producing contrast enhancement and reduction of information sent to L4. Monopolar cell L4 is thought to perform image segmentation on the information input from L1 and L2 and also enhance edge detection. A mesh of interconnected L4's would correlate the output from L1 and L2 cells of adjacent cartridges and provide a parallel network for segmenting an object's edges. The focus of this research is to excite photoreceptors of the common housefly, Musca domestica, with different visual patterns. The electrical response of monopolar cells L1, L2, and L4 will be recorded using intracellular recording techniques. Signal analysis will determine the neurocircuitry to detect and segment images.

Animals↗
PubMed2002

Intermodal spatial attention differs between vision and audition: an event-related potential analysis.

Subjects were required to attend to a combination of stimulus modality (vision or audition) and location (left or right). Intermodal attention was measured by comparing event-related potentials (ERPs) to visual and auditory stimuli when the modality was relevant or irrelevant, while intramodal (spatial) attention was measured by comparing ERPs to visual and auditory stimuli presented at relevant and irrelevant spatial locations. Intramodal spatial attention was expressed differently in visual and auditory ERPs. When vision was relevant, spatial attention showed a contralateral enhancement of posterior N1 and P2 components and enhancement of parietal P3. When audition was relevant, spatial attention showed a biphasic fronto-central negativity, starting after around 100 ms. The same effects were also present in ERPs to stimuli that were presented in the irrelevant modality. Thus, spatial attention was not completely modality specific. Intermodal attention effects were also expressed differently in vision and audition. Taken together, the obtained ERP patterns of the present study show that stimulus attributes such as modality and location are processed differently in vision and audition.

Adolescent↗
PubMed2002

Vision care benefits and outcomes of treatment of keratoconus.

Coverage for basic vision care services is offered by a number of national and regional vision care networks. When eyewear is covered, cosmetic contact lenses are usually provided in lieu of glasses. There are a few disorders for which contact lenses are prescribed for a "medically necessary" condition; keratoconus is an example. Some plans provide full benefits for noncosmetic contact lenses for the treatment of keratoconus, and outcomes measures have demonstrated that visual improvement has been excellent. Evidence of the vision benefit offered to those with keratoconus is found in patient-satisfaction surveys, which provide self-reports of improvements in near and distance vision.

Adolescent↗
PubMed2003

Color vision with rapid-onset acceleration.

INTRODUCTION: Only sporadic information exists concerning perceived color shifts at increased G-loads. The purpose of this study was to investigate whether or not color vision is affected by rapid onset high G7-loads up to +9 Gz, and specifically whether perception of hue changes. METHODS: There were 10 male subjects, 9 with normal color vision and 1 with red-green protanomaly, all accustomed to Gz-loads in a human centrifuge. Each subject was tested on a total of 60 Gz-exposures with 10 s periods at +3, +5, +7, and +9 Gz in the centrifuge on three different days. G-onset rate was 6 G x s(-1). The subjects wore an anti-G suit and performed straining maneuvers if necessary to maintain vision. Five square color stimuli of medium saturation (yellow, red, blue, green, and gray) were projected one at a time on a screen in front of the subject, who gave his hue response orally. RESULTS: In 96.6% of exposures to various Gz-loads, the subjects responded by correctly naming colors. (The statistical analyses of the results were done for the subjects with normal color vision, with the protanomalous subject excluded.) Hue shifts occurred at the higher +Gz-levels, including 7.7% of the +9 Gz exposures. Yellow was the hue most frequently perceived as changed. Hue shifts were reported for yellow in 11% and 16% of the +7 and +9 Gz exposures, respectively. Hue shifts at +9 Gz occurred as frequently as blackout and G-LOC together. However, statistical analyses showed no significant effects for +Gz-load. CONCLUSIONS: Absolute identification of the color stimuli of medium saturation was stable and was not significantly affected by the rapid onset +Gz-loads up to and including +9 Gz.

Acceleration↗
PubMed2003

Comparison of direct vision and video imaging during bronchoscopy for pediatric airway foreign bodies.

Rigid ventilation bronchoscopy is a most useful means of detecting and removing foreign bodies in the airway. We performed a retrospective study of 114 children who had undergone such a procedure during a 12-year period. During bronchoscopy, 48 of these patients had been examined under direct vision and 66 by videotape recording. We found that the positive rate on first-look direct vision was 93.8% and the positive rate on first-look video imaging was 89.4%. The lower positive rate during the first-look examination by video imaging might be attributable to the facts that it is safer and that it provides a better visual field, which can encourage operators to choose video ventilation bronchoscopy, either as a diagnostic or therapeutic tool. In addition, three foreign-body-negative patients in the direct-vision group under-went a second procedure, and a foreign body was found in all three. Only one of the video-imaging patients under-went a second procedure, and no foreign body was found. The difference in the positive rates after the second procedure was statistically significant (p < 0.05). This might be attributable to the higher success rate with video imaging following the first procedure, which significantly reduced the need for a second look and the possibility of overlooked or residual foreign bodies. The condition of the mucosa postprocedurally was described in every case after video imaging but after only 41.7% of the direct-vision cases--a statistically significant difference (p < 0.001). Video imaging provides the physician with a clear, magnified view of the area under examination. It allows for later review of the videotape when necessary, and it reduces the risk that residual foreign-body material will remain in the airway.

Bronchoscopy↗
PubMed1999

Editorial: Residual vision and plasticity after visual system damage.

This is an introduction to a special issue of the journal Restorative Neurology and Neuroscience which contains a series of papers presented at a satellite symposium held in conjunction with the European Forum of Neuroscience, Berlin, July 1-2, 1998, entitled "Visual System Damage: Residual Vision and Plasticity". The symposium highlighted research findings both from animals and humans which sustained brain injury in early development and in adulthood. The findings demonstrate the degree of residual vision the injured brain possesses and summarize the effects of drugs and training on the plasticity of the visual system. As this conference demonstrated, the visual system is able to respond in many ways in an adaptive manner to lesions inflicted early in life and in adulthood. These changes may bring about spontaneous recovery of visual functions as long as the brain contains a sufficient capacity of residual vision. Both in children and in adults, systematic visual training can help patients to regain some visual functions which have previously been considered to be irrevocably lost. By carefully assessing residual vision it is proposed that the potential for plasticity of the visual system can be utilized to achieve clinical improvement using appropriate training paradigms.

Editorial↗