visual acuity (redirected from Twenty-twenty vision)

visual acuity

n.

Sharpness of vision, especially as tested with a Snellen chart. Normal visual acuity based on the Snellen chart is 20/20.

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Visual acuity

The ability to distinguish details and shapes of objects.

Mentioned in: Amblyopia, Myopia, Presbyopia

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visual acuity

Etymology: L, visus, vision, acuitas, sharpness

1 a measure of the resolving power of the eye, particularly with its ability to distinguish letters and numbers at a given distance.

2 the sharpness or clearness of vision.

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acuity (kyōōitē),

n sharpness; clearness; keenness.

acuity, auditory,

n the sensitivity of the auditory apparatus; sharpness of hearing. The ability to hear a given tone with respect to the degree of intensity required to produce a sensation that is just perceptible.

acuity, visual,

n sharpness, acuteness, clearness of vision. Visual acuity may be defective because of optical or neurologic dysfunction.

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agnosia 

Inability to recognize the import of sensory stimuli (e.g. to recognize colour, faces, shape and the orientation of objects), although the receptors and the sensory pathway are intact. The condition is attributed to bilateral lesions in the association areas of the cortex. If the sense of sight is affected, it is called visual agnosia (perceptual or psychic blindness). See alexia; optical apraxia; prosopagnosia.

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agraphia 

Inability to write, usually as a result of a brain lesion. If the person can write from dictation but not from copying, it is called visual agraphia.

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visual acuity

Central vision Ophthalmology The ability to distinguish details and shapes of objects; a measure of the ability to resolve distinct objects or fine details with the eye