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The Posner cueing task, also known as the Posner paradigm, is a neuropsychological test often used to assess attention. Formulated by Michael Posner, [1] it assesses a person's ability to perform an attentional shift. It has been used and modified to assess disorders, focal brain injury, and the effects of both on spatial attention.
The visual field index (VFI) reflects retinal ganglion cell loss and function, as a percentage, with central points weighted more. [21] It is expressed as a percentage of visual function; with 100% being a perfect age-adjusted visual field and 0% represents a perimetrically blind field.
This type of perimetry is the most commonly used in clinical practice, and in research trials where loss of visual field must be measured. [4] However, the sensitivity of white-on-white perimetry is low, and the variability is relatively high; as many as 25–50 percent of the photoreceptor cells may be lost before changes in visual field ...
Confrontation visual field testing is an important part of a routine ophthalmological or neurological examination. It can be used for rapid and gross assessment of large-scale visual field problems due to ophthalmological or neurological diseases, such as homonymous and heteronymous hemianopias, quadranopsia, altitudinal visual loss, central/centrocecal scotoma etc. [1] [2] Test using a red ...
The traditional UFOV assessment is a computer-based visual test containing three subtests. [citation needed] Processing Speed: Determines threshold for discriminating stimuli presented in central vision. Divided Attention: Same as 1, but with the addition of a concurrent peripheral target location task.
Testing the visual fields consists of confrontation field testing in which each eye is tested separately to assess the extent of the peripheral field. Normal visual field of a right eye. To perform the test, the individual occludes one eye while fixated on the examiner's eye with the non-occluded eye.
Spatial attention allows humans to selectively process visual information through prioritization of an area within the visual field. A region of space within the visual field is selected for attention and the information within this region then receives further processing. Research shows that when spatial attention is evoked, an observer is ...
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"; [1] in ophthalmology and neurology the emphasis is mostly on the structure inside the visual field and it is then considered “the field of functional capacity obtained and recorded by means of perimetry”.