We present a biologically inspired active vision system that incorporates two modes of perception. A peripheral mode provides a broad and coarse perception of where mass is in the scene in the vicinity of the current fixation point, and how that mass is moving. It involves fusion of actively acquired depth data into a 3D occupancy grid. A foveal mode then ensures coordinated stereo fixation upo...

During attempted visual fixation, small involuntary eye movements-called fixational eye movements-continuously change of our gaze's position. Disagreement between the left and right eye positions during such motions can produce diplopia (double vision). Thus, the ability to properly coordinate the two eyes during gaze fixation is critical for stable perception. For the last 50 years, researcher...

purpose: to report two patients with keratoconus who underwent regrafting to correct anisometropia and high astigmatism after penetrating keratoplasty. patients and findings: the first case is a 34-year-old man with keratoconus who had undergone penetrating keratoplasty. the sutures were removed 6 months postoperatively that led to high hyperopia. regraft was performed considering vitreous leng...

Binocular vision provides important information about depth to help us navigate in a three-dimensional environment and allows us to identify and manipulate 3D objects. The relative depth of any feature with respect to fixation can be determined by triangulating the horizontal shift or disparity between the images of this feature projected onto the left and the right eyes. The computation is dif...

Primates explore their visual environment by redirecting the gaze to objects of interest by alternating eye movements and periods of steady fixation. During this task, the fixation point changes frequently in depth. Therefore, the representation of object location based on retinal disparity requires frequent updating. Neural activity was recorded in the lateral intraparietal (LIP) area while mo...

background hepatitis c virus (hcv) infection is the most significant source of chronic liver diseases in the globe. about 170 million individuals are infected by hcv worldwide. the reported prevalence of hcv in different areas of khyber pakhtunkhwa (kp) ranges from 4.1 to 36%. objectives the current study aimed to analyze the true prevalence of hcv infection in khyber pakhtunkhwa, pakistan. mat...

PURPOSE Infantile esotropia is linked strongly to latent fixation nystagmus (LN) in human infants, but many features of this comorbidity are unknown. The purpose of this study was to determine how the duration of early-onset strabismus (or timeliness of repair) affects the prevalence of LN in a primate model. METHODS Optical strabismus was created in infant macaques by fitting them with prism...

Depth can be perceived in random-dot stereograms in which dots are binocularly uncorrelated, in the absence of overall positional disparity (e.g., Julesz, 1960). This phenomenon, which we have called rivaldepth, persists over a wide range of luminances, stereogram dot densities, and dot sizes. Rivaldepth is also observed with interocular uncorrelation provided by complementation and orthogonal ...

With the broader use of stereoscopic displays, a flurry of research activity about the accommodation-vergence conflict has emerged to highlight the implications for the human visual system. In stereoscopic displays, the introduction of binocular disparities requires the eyes to make vergence movements. In this study, we examined vergence dynamics with regard to the conflict between the stimulus...

Fixation disparity or vergence noise produce instantaneous vergence errors. These errors are analogous to the imposition of a pedestal disparity, which is known to elevate stereothresholds. In this study, stereothresholds were measured as a function of induced vergence errors in subjects with normal binocular vision. Stereo half-images were viewed in the dark through a custom mirror haploscope....