The visual field is "that portion of space in which objects are visible at the same moment during steady fixation of the gaze in one direction"; in ophthalmology...

A visual field test is an eye examination that can detect dysfunction in central and peripheral vision which may be caused by various medical conditions...

Confrontation visual field testing is a test used in ophthalmology for rapid and gross detection of large-scale visual field problems. It is done by asking...

brain include a visual cortex; the visual cortex in the left hemisphere receives signals from the right visual field, and the visual cortex in the right...

Humphrey field analyser (HFA) is a tool for measuring the human visual field that is commonly used by optometrists, orthoptists and ophthalmologists,...

(nicknamed blue-sky sprites) moving quickly along undulating pathways in the visual field, especially when looking into bright blue light such as the sky. The...

Lesions in that pathway cause a variety of visual field defects. In the visual system of human eye, the visual information processed by retinal photoreceptor...

transparent, or colored dots across the whole visual field. It is distinct from the symptom of visual snow, which can also be caused by several other...

in specifying visual fields. According to IPS Perimetry Standards 1978 (2002): "Perimetry is the measurement of [an observer's] visual functions ... at...

excluded in the visual field's definition. Humans have a slightly over 210-degree forward-facing horizontal arc of their visual field (i.e. without eye...

Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear...

the receptive field ranges from the unidimensional chemical structure of odorants to the multidimensional spacetime of human visual field, through the...

resolved in the very center of the visual field; it therefore does not indicate how larger patterns are recognized. Visual acuity alone thus cannot determine...

Visual hierarchy, according to Gestalt psychology, is a pattern in the visual field wherein some elements tend to "stand out," or attract attention, more...

vision at all,[citation needed] and in fact is hard to notice if the visual field is highly patterned, complex, or in motion.[citation needed] When active...

central visual field. The grid was developed by Marc Amsler, a Swiss ophthalmologist. It is a diagnostic tool that aids in the detection of visual disturbances...

The visual system is the physiological basis of visual perception (the ability to detect and process light). The system detects, transduces and interprets...

8 steps of visual acuity, pupil function, extraocular muscle motility and alignment, intraocular pressure, confrontational visual fields, external examination...

or hemianopia, is a loss of vision or blindness (anopsia) in half the visual field, usually on one side of the vertical midline. The most common causes...

peripheral vision, tunnel vision, occurs. Because of constant motion, the visual field of a driver is usually not stable. To monitor changes in our environment...

Visual agnosia is an impairment in recognition of visually presented objects. It is not due to a deficit in vision (acuity, visual field, and scanning)...

Bjerrum's area is the central 25° of the visual field from the fixation point, popularized scientifically by the Danish ophthalmologist Jannik Petersen...

Macular sparing is visual field loss that preserves vision in the center of the visual field, otherwise known as the macula. It appears in people with...

ignore the other visual field and to not respond to the targets presented in that visual field. When targets in the attended visual field are compared to...

noticeable patterns are seen in the visual field. Most of the early glaucomatous changes are seen within the central visual field, mainly in Bjerrum's area, 10-20°...

presented on the left or right visual hemifields. If a visual stimulus appears in the left visual field (LVF), the visual information is initially projected...

visual field, growing research in this field relies heavily on nonverbal cues including an infant's perceived ability to detect patterns and visual changes...

were instructed to either attend to the left visual field, the right visual hemisphere, or both visual hemispheres for a double flash (two flashes within...

The equine eye is one of the largest of any land mammal. Its visual abilities are directly related to the animal's behavior; for example, it is active...

parietal lobe of the brain can lead to neglect for the left side of the visual field, causing a patient with neglect to behave as if the left side of sensory...