Papers by Duane Geruschat
Developing a Rehabilitation Curriculum for Argus® II System Users
Investigative Ophthalmology & Visual Science, Jun 16, 2013
Optometry and Vision Science, Jul 1, 2003
Background. Crossing the street is a complex task that involves gathering, processing, and acting... more Background. Crossing the street is a complex task that involves gathering, processing, and acting on information that is time dependent. The gaze behavior of subjects has been previously studied on increasingly complex and dynamic tasks such as making tea, walking indoors, and driving. The purpose of this study was to assess how normally sighted people use their vision to cross a street safely. Specifically, we identified the environmental features people look at when crossing two types of intersections. Method. We measured the eye movements and head directions of 12 normally sighted people as they approached, evaluated, and crossed a light-controlled "plus" intersection and a roundabout. The primary measures were percentage of fixations and head direction. Results. Crossing the street can be divided into three phases, walking to the curb, standing at the curb, and crossing the street. We found that while moving, subjects fixated primarily on crossing elements and when standing at the curb, they fixated primarily on vehicles. At the plus intersection, fixation behavior corresponded with crossing strategy; the subjects who crossed early fixated on cars, and the subjects who waited for the light to change fixated on traffic controls. At the roundabout, all subjects determined an appropriate time to cross from vehicular traffic flow by directing the majority of their fixations on cars. When moving, the head position of subjects was predominately centered. Subjects also made head turns in both directions before crossing and directed the head toward the danger zone while crossing. Conclusion. Crossing the street is a complex task that can be described in three phases. Common head and eye behaviors were found near the critical moments of crossing the street. Fixation behavior was closely related to street crossing behavior.
PLOS digital health, Jun 20, 2023
Visual impairment represents a significant health and economic burden affecting 596 million globa... more Visual impairment represents a significant health and economic burden affecting 596 million globally. The incidence of visual impairment is expected to double by 2050 as our population ages. Independent navigation is challenging for persons with visual impairment, as they often rely on non-visual sensory signals to find the optimal route. In this context, electronic travel aids are promising solutions that can be used for obstacle detection and/or route guidance. However, electronic travel aids have limitations such as low uptake and limited training that restrict their widespread use. Here, we present a virtual reality platform for testing, refining, and training with electronic travel aids. We demonstrate the viability on an electronic travel aid developed in-house, consist of a wearable haptic feedback device. We designed an experiment in which participants donned the electronic travel aid and performed a virtual task while experiencing a simulation of three different visual impairments: age-related macular degeneration, diabetic retinopathy, and glaucoma. Our experiments indicate that our electronic travel aid significantly improves the completion time for all the three visual impairments and reduces the number of collisions for diabetic retinopathy and glaucoma. Overall, the combination of virtual reality and electronic travel aid may have a beneficial role on mobility rehabilitation of persons with visual impairment, by allowing earlyphase testing of electronic travel aid prototypes in safe, realistic, and controllable settings.
Using the Acuity Card Procedure to Assess Visual Acuity in Children with Severe and Multiple Impairments
Journal of Visual Impairment & Blindness, 1992
Orientation and Mobility for the Low Functioning Deaf-Blind Child
Journal of Visual Impairment & Blindness, 1980
Journal of Visual Impairment & Blindness, Jun 1, 1993
Assessing the status of a school's graduates is one approach to program evaluation. Of specific c... more Assessing the status of a school's graduates is one approach to program evaluation. Of specific concern to students, parents, and teachers is employment and housing. This article describes the findings of a study that evaluated the employment and housing status for five years of graduates from a residential school for the blind. The findings suggest that a high rate of placement was achieved, but that many graduates are not receiving competitive wages. Graduates who were not capable of competitive or supported employment also experienced a high rate of placement. Most of the graduates lived with their parents and were not looking to change this arrangement.
Dr. Geruschat's Farewell
Journal of Visual Impairment & Blindness, Sep 1, 2012
Seven years ago, on September l, 2004, I became acting editor in chief of the Journal of Visual I... more Seven years ago, on September l, 2004, I became acting editor in chief of the Journal of Visual Impairment & Blindness (JVIB), assuming the title of editor in chief on January 1, 2005. I became acting editor in chief because of the serious health issues facing my predecessor Alan Koenig--health challenges that ultimately took his life in early 2005. I begin my last editorial as editor in chief with this information because I often think of Dr. Koenig, the tragic and sudden end to his life, and how this loss provided me with the responsibility and the opportunity to lead this wonderful journal. I hope that I filled his large shoes and made him proud. During the past seven years JVIB has experienced a number of changes with technology that have allowed us to increase the efficiency of our operation. We have evolved from paper submissions to CDs, and now to an entirely online process. Technology has allowed us to share final decision letters with the peer reviewers so they can learn from each other. I know from comments I have received over the years that all peer reviewers appreciate this change. JVIB has instituted structured abstracts. The 300-word summaries are more in line with those of other scholarly journals, and they provide a substantive overview of the full manuscript. Starting in January 2013, the journal will become what is known as an ePublication, offered in a variety of formats, all totally accessible to the reader. I am especially proud of our ability to manage the high volume of submissions. Averaging 120 new submissions per year, my office processed manuscript number 1,000 this summer. As word of my retirement from JVIB became known, a number of people approached me to comment that I had maintained the high standard and integrity of the journal. Nothing more important could be said to me. I have always been humbled by the responsibility of this position; of the importance of JVIB as the archive of the professions, publication in which can either advance or thwart academic careers; and JVIB's role as the repository of information that can improve the lives of those who receive our services. And now to my acknowledgements of the people who made a difference in my work as editor in chief. The unconditional support of Carl Augusto, president and CEO of the American Foundation for the Blind (AFB), and Maureen Matheson, vice president of AFB Press and Information Services, during difficult financial times allowed JVIB to thrive. Natalie Hilzen, director and editor in chief of AFB Press, Rebecca Burrichter, senior editor for JVIB, and Jenese Croasdale-Griffiths, permissions coordinator for AFB Press, were always there to answer my many questions and to offer gentle guidance on all sorts of issues. …
Journal of Visual Impairment and Blindness: Guest editorial
Journal of Visual Impairment & Blindness, Oct 1, 2004
Peripheral Vision Expander System (Pves) for People with Concentric Field Loss
Optometry and Vision Science, Dec 1, 1995
Activities of Daily Living and Rehabilitation with Prosthetic Vision
Springer eBooks, 2011
... M., 118, 125 Abrams, GW, 178 Abrams, LD, 139 Abzug, C., 304 Acland, GM, 272 Adachi, K., 85 Ad... more ... M., 118, 125 Abrams, GW, 178 Abrams, LD, 139 Abzug, C., 304 Acland, GM, 272 Adachi, K., 85 Adrian, ED, 283 Agnew, WF, 124, 131, 132, 151, 153, 213215, 294 Aguirre, GD, 62, 272 Aguirre, GK, 272 Ahmadi, H., 391 Ahnelt, P., 311 Ahnelt, PK, 4, 5, 7, 26 Ahuja, AK, 18, 120 ...
A Farewell to Corinne Kirchner
Journal of Visual Impairment & Blindness, 2007
Journal of Visual Impairment & Blindness, Oct 1, 2004
This article describes federal and state laws that affect the opportunity of people with low visi... more This article describes federal and state laws that affect the opportunity of people with low vision to drive and to obtain driver's licenses. Discrimination against individuals with low vision is discussed in the context of equal protection and the Americans with Disabilities Act. A review of relevant case law and implications for drivers with low vision are presented.
Journal of Visual Impairment & Blindness, 1994
Journal of Visual Impairment & Blindness, 1992
Optometry and Vision Science, Jul 1, 1998
Comparing the item measures of an Ultra-low vision (ULV) questionnaire with those of a ULV assessment toolkit
Reliability and Validity of O&M Instructor Observations
Journal of Visual Impairment & Blindness, Nov 1, 1989
The development of a reliable and valid approach to the assessment of orientation and mobility sk... more The development of a reliable and valid approach to the assessment of orientation and mobility skills has been difficult to attain. The purpose of this study was to assess the efficacy of quantifying the observations of practicing orientation and mobility instructors in a naturalistic setting. Mobility clients currently enrolled in a rehabilitation center were asked to walk a residential/small business route at the beginning and end of their instructional program. The mobility staff was required to observe the clients’ travel skills and to record events in five critical areas. Results of this experiment suggest that orientation and mobility personnel can develop consistent observation strategies for use as an ongoing evaluation procedure.
Optometry and Vision Science, Sep 1, 2012
As the companies developing the various types of prosthetic vision devices move towards commercia... more As the companies developing the various types of prosthetic vision devices move towards commercialization, the importance of measuring the impact of these technologies on performance of activities of daily living (ADL) has become apparent. One of the daily activities that has been identified as potentially benefiting from prosthetic vision is orientation and mobility (O&M).
Mental Effort Required for Walking: Effects of Retinitis Pigmentosa
Optometry and Vision Science, Dec 1, 1998
To determine whether retinitis pigmentosa (RP) increases the mental effort required for walking. ... more To determine whether retinitis pigmentosa (RP) increases the mental effort required for walking. A dual-task methodology was used; walking speed and reaction time (RT) to randomly emitted tones were measured in 13 persons with RP and 29 persons with normal vision. Measures of RT were used to estimate the mental effort required for walking. In a second experiment, 15 persons with RP and 17 persons with normal vision navigated a "simple" and a "complex" route. The RP subjects had longer RT compared with the normal-vision subjects when walking the complex but not the simple route. Normalized to each person's baseline, RT while walking the complex route was significantly correlated with log contrast sensitivity (r = -0.63) and log retinal area (r = -0.64) in the RP group. The amount of mental effort required for walking was shown to also depend on familiarity with the route. Route complexity is critical in determining whether walking requires more mental effort for persons with RP than for persons with normal vision. The magnitude of mental effort required for mobility covaries with the visual impairment measures which correlate with mobility performance in RP.
Vision Research, Feb 1, 2003
Laboratory-based models of oculomotor strategy that differ in the amount and type of top-down inf... more Laboratory-based models of oculomotor strategy that differ in the amount and type of top-down information were evaluated against a baseline case of random scanning for predicting the gaze patterns of subjects performing a real-world activity-walking to a target. Images of four subjectsÕ eyes and field of view were simultaneously recorded as they performed the mobility task. Offline analyses generated movies of the eye on scene and a categorization scheme was used to classify the locations of the fixations. Frames from each subjectÕs eye-on-scene movie served as input to the models, and the location of each modelÕs predicted fixations was classified using the same categorization scheme. The results showed that models with no top-down information (visual salience model) or with only coarse feature information performed no better than a random scanner; the modelsÕ ordered fixation locations (gaze pattern) matched less than a quarter of the subjectsÕ gaze patterns. A model that used only geographic information outperformed the random scanner and matched approximately a third of the gaze patterns. The best performance was obtained from an oculomotor strategy that used both coarse feature and geographic information, matching nearly half the gaze patterns (48%). Thus, a model that uses top-down information about a targetÕs coarse features and general vicinity does a fairly good job predicting fixation behavior, but it does not fully specify the gaze pattern of a subject walking to a target. Additional information is required, perhaps in the form of finer feature information or knowledge of a taskÕs procedure.
Uploads
Papers by Duane Geruschat