We demonstrate that humans can use optic flow to estimate distance travelled when appropriate scaling information is provided. Eleven subjects were presented with visual targets in a virtual corridor. They were then provided with optic flow compatible with movement along the corridor and asked to indicate when they had reached the previously presented target position. Performance depended on th...

Optic flow fields provide rich information about the observer's self-motion. Besides estimation of the direction of self-motion human observers are also able to discriminate the travel distances of two self-motion simulations. Recent studies have shown that observers estimate the simulated ego velocity of the self-motion simulation and integrate it over time. Thus, observers use a 3-D percept o...

We studied the accuracy of human subjects in perceiving the direction of self-motion from optic flow, over a range of directions contained in a 45 deg cone whose vertex was at the viewpoint. Translational optic flow fields were generated by displaying brief sequences (< 1.0 sec) of randomly positioned dots expanding in a radial fashion. Subjects were asked to indicate the direction of perceived...

Estimating our egocentric heading direction is an important component of navigation. Recent studies have explored how inertial cues from the vestibular system and optic flow signals from the visual system interact to improve perceptual precision and accuracy. Heading precision is improved through multisensory integration, whereas heading accuracy is maintained through multisensory calibration m...

The aim of the study was to determine the incidence of monosymptomatic optic neuritis (MON) in residents of Split-Dalmatia County, Croatia. The 127 cases (83 female, aged 26.2+/-9.9 and 44 male aged 26.9+/-11.2) with MON presented between January 1985 and December 2001 were analyzed from hospital data. The annual incidence was 1.6 per 100,000 (95% CI, 0-3). The incidence among females was 2.2 (...

The axons that make up the optic nerve originate from the retinal ganglion cells and extend from there to the lateral geniculate body. If cellular integrity is interrupted by disease anywhere along the course of an axon, degeneration occurs in both directions from the point of insult. Thus, axon frag­ ments between the site of injury and the lat­ eral geniculate body are separated from their nu...

The current study presents the case of a patient with a rare adverse event characterized by sudden vision loss in the untreated eye following an intravitreal injection of bevacizumab for neovascular glaucoma (NVG). The patient was diagnosed with NVG refractory to Ahmed glaucoma valve implantation and a vitreous hemorrhage in the right eye, which was treated with 1.25 mg intravitreal bevacizumab...

Retinal ganglion cell (RGC) axons travel in radial routes unerringly toward the optic disk, their first intermediate target in the center of the eye. The path of the RGC growth cone is restricted to a narrow zone subjacent to the endfeet of Müller glial cells and the vitreal basal lamina. The present survey indicates that RGC growth cones are guided by many molecular cues along their pathway wh...

Fundus video cameras enable the acquisition of image sequences to analyze fast temporal changes on the human retina in a noninvasive manner. In this work, we propose a tracking-by-detection scheme for the optic disk to capture the human eye motion on-line during examination. Our approach exploits the elliptical shape of the optic disk. Therefore, we employ the fast radial symmetry transform for...

background: optical coherence tomography (oct) is a simple, high-resolution technique to quantify the thickness of retinal nerve fiber layer (rnfl) and macula volume, which provide an indirect measurement of axonal damage in multiple sclerosis (ms). this study aimed to evaluate oct finding in relapsing-remitting ms patients of the northwest of iran and compare them with a normal control group. ...