A5069139089- Glaucoma and retinal disorders
- Visual perception and processing mechanisms
- Ophthalmology and Visual Impairment Studies
- Vestibular and auditory disorders
- Ophthalmology and Eye Disorders
- Gaze Tracking and Assistive Technology
- Retinal Imaging and Analysis
- Retinal Diseases and Treatments
- Stellar, planetary, and galactic studies
- Spatial Neglect and Hemispheric Dysfunction
- Astrophysics and Star Formation Studies
- Retinal Development and Disorders
- Neurobiology and Insect Physiology Research
- Human auditory perception and evaluation
- Astronomical Observations and Instrumentation
- Balance, Gait, and Falls Prevention
- Hemispheric Asymmetry in Neuroscience
- Cerebral Palsy and Movement Disorders
- Physiological and biochemical adaptations
- Biochemical effects in animals
- Retinal and Optic Conditions
- Astronomy and Astrophysical Research
- Virtual Reality Applications and Impacts
- Military Defense Systems Analysis
- Ocular Surface and Contact Lens
Smith-Kettlewell Eye Research Institute
2016-2025
University of Michigan
2010-2011
University of Chicago
2005-2006
We have studied a sample of 809 Mg II absorption systems with 1.0 < z_abs 1.86 in the spectra SDSS QSOs, aim understanding nature and abundance dust chemical abundances intervening absorbers. Normalized, composite were derived, for measurements, full several sub-samples, chosen on basis line strengths other absorber QSO properties. Average extinction curves obtained sub-samples by comparing their geometric mean those matching samples QSOs without absorbers spectra. There is clear evidence...
Currently, there are no quantitative studies of smooth pursuit, a behavior attributed to the fovea, in individuals with macular degeneration (MD). We hypothesize that pursuit MD patients depends on relative positions scotoma and target trajectory. tested this hypothesis scanning laser ophthalmoscope (SLO), which allows for direct visualization damaged retina. Monocular microperimetry eye movements were assessed eleven differing degrees MD. Observers asked visually track 1.7° moved one eight...
Loss of central vision affects a variety activities daily living, limiting high acuity tasks like reading and increasing isolation due to loss mobility decreases in physical social activity. These outcomes are known affect healthy aging can be associated with accelerated cognitive decline. Here, we explore how changes compare sighted controls. Participants macular-affecting pathologies (MAP) age-matched controls were recruited both the USA UK. Cognitive function was assessed using an adapted...
In this study, we address the question of whether a target is foveated during smooth pursuit. Specifically, examine pursuit eye movements land near center-of-mass target, as case for saccades. To that end, instructed eight untrained, healthy participants to follow moving targets, presented monocularly in scanning laser ophthalmoscope. Stimuli moved either modified step-ramp (smooth pursuit), or made single step (saccade), stepping 6° from center. Targets were ring-shaped and 0.6° 1.7°...
Motion information is essential in daily life because it provides cues to depth, timing, object identification, and self-motion, as well input the oculomotor system. As peripheral visual field exquisitely sensitive motion, we investigated periphery of individuals with central loss (CFL) determine whether speed direction discrimination are intact this population. We compared CFL participants' (N = 8), older 6), young controls' 6) ability discriminate motion a two-spatial-alternative...
Macular degeneration (MD) often leads to the loss of fovea and surrounding central visual field. This type is very common can present particular challenges for oculomotor tasks that may rely on fovea. For certain tasks, individuals develop a new, eccentric fixational locus. Our previous work has shown smooth pursuit impaired in MD. However, extent retinal lesion size eccentricity fixation do not directly contribute changes gain. Oculomotor limitations due eye position orbit be another...
Purpose: To examine whether the age-related increase in visual field dependence persists older adults with central loss (CFL). Methods: Twenty individuals CFL were grouped into participants binocular (CFL, n = 9), monocular CFL/relative scotomata (mCFL, 8), and occurring at a young age (yCFL, 3). Seventeen controls age-matched to groups (OA) three yCFL group (yOA). Participants judged tilt direction of rod presented various orientations under conditions without reference. Visual was...
SIGNIFICANCE Prior studies with large, highly visible targets report low smooth pursuit gains in individuals macular degeneration (MD). We show that lower persist even when observers are pursuing a target requires discrimination at the acuity limit. This gain causes retinal slip, potentially leading to motion blur and disappearance scotoma, which further compromise visibility of moving object. PURPOSE In this study, we examine whether characteristics (pursuit placement fixational locus...
Irregular vestibular afferents exhibit significant phase leads with respect to angular velocity of the head in space. This characteristic and their connectivity vestibulospinal neurons suggest a functionally important role for these producing vestibulo-collic reflex (VCR). A goal experiments was test this hypothesis use weak galvanic stimulation periphery (GVS) selectively activate or suppress irregular during passive whole body rotation guinea pigs that could freely move heads. Both...
The timed up and go test (TUG) is a common clinical functional balance often used to complement findings on sensorimotor changes due aging or sensory/motor dysfunction. instrumented TUG can be obtain objective postural gait measures that are more sensitive mobility changes. We investigated whether body coordination during representative of walking. examined the walking phase compared metrics (stride duration length, speed, step frequency) head/trunk accelerations normal latter key aspect...
Developments in wearable eye tracking devices make them an attractive solution for studies of movements during naturalistic head/body motion. However, before these systems' potential can be fully realized, a thorough assessment sources error is needed. In this study, we examine three possible the Pupil Core goggles: camera motion motion, choice calibration marker configuration, and movement estimation. our data, find that up to 36% reported may attributable movement; appropriate routine...
Loss of the central retina, including fovea, can lead to a loss visual acuity and oculomotor deficits, thus have profound effects on day-to-day tasks. Recent advances in head-mounted, 3D eye tracking allowed researchers extend studies this population broader set daily tasks more naturalistic behaviors settings. However, decreases fixational stability, multiple loci their uncertain role as references, well eccentric fixation all provide additional challenges for calibration collection...
We find evidence for dust in the intervening QSO absorbers from spectra of QSOs Sloan Digital Sky Survey Data Release 1. No is found 2175 Å feature which present Milky Way extinction curve.
The spectra of the Sloan Digital Sky Survey (SDSS) are being used to construct a catalogue QSO absorption lines, for use in studies abundances, relevant radiation fields, number counts as function redshift, and other matters, including evolution these parameters. includes intervening, associated, BAL absorbers, order allow clearer definition relationships between three classes. We describe motivation data products project build SDSS line catalogue.