Biomaterial Database

Vernier acuity of normal and visually deprived cats. 1991

K M Murphy, and D E Mitchell

University of California, School of Optometry, Berkeley 94720.

This study examines the relationship between grating and vernier acuity in cats that were either normally reared, unilaterally amblyopic as a result of a period of monocular deprivation, or bilaterally amblyopic resulting from a period of reverse occlusion followed by binocular visual experience. Vernier acuity was assessed on a jumping stand by use of a vernier-grating stimulus similar to that devised for use with human infants. The vernier thresholds for normal cats were 1.2-1.3 min arc, values that were approx. 6 times better than their grating acuity, and hence may represent a true hyperacuity. By contrast, the vernier acuity of the visually deprived cats were substantially below normal (19-83 min arc). The vernier thresholds for the deprived eye of the monocularly deprived cat and both eyes of the reverse occluded cats had fallen to the point where they were at best equal, and sometimes worse than the corresponding grating acuity. This pattern of results is similar to those observed in some types of human amblyopia, where vernier acuity also no longer represents a hyperacuity, and where in severe cases the thresholds may be worse than grating acuity.

UI	MeSH Term	Description	Entries
D010364	Pattern Recognition, Visual	Mental process to visually perceive a critical number of facts (the pattern), such as characters, shapes, displays, or designs.	Recognition, Visual Pattern,Visual Pattern Recognition
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D000550	Amblyopia	A nonspecific term referring to impaired vision. Major subcategories include stimulus deprivation-induced amblyopia and toxic amblyopia. Stimulus deprivation-induced amblyopia is a developmental disorder of the visual cortex. A discrepancy between visual information received by the visual cortex from each eye results in abnormal cortical development. STRABISMUS and REFRACTIVE ERRORS may cause this condition. Toxic amblyopia is a disorder of the OPTIC NERVE which is associated with ALCOHOLISM, tobacco SMOKING, and other toxins and as an adverse effect of the use of some medications.	Anisometropic Amblyopia,Lazy Eye,Amblyopia, Developmental,Amblyopia, Stimulus Deprivation-Induced,Amblyopia, Suppression,Stimulus Deprivation-Induced Amblyopia,Amblyopia, Anisometropic,Amblyopia, Stimulus Deprivation Induced,Amblyopias,Amblyopias, Anisometropic,Amblyopias, Developmental,Amblyopias, Stimulus Deprivation-Induced,Amblyopias, Suppression,Anisometropic Amblyopias,Deprivation-Induced Amblyopia, Stimulus,Deprivation-Induced Amblyopias, Stimulus,Developmental Amblyopia,Developmental Amblyopias,Eye, Lazy,Eyes, Lazy,Lazy Eyes,Stimulus Deprivation Induced Amblyopia,Stimulus Deprivation-Induced Amblyopias,Suppression Amblyopia,Suppression Amblyopias
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012683	Sensory Deprivation	The absence or restriction of the usual external sensory stimuli to which the individual responds.	Deprivation, Sensory,Deprivations, Sensory,Sensory Deprivations
D012684	Sensory Thresholds	The minimum amount of stimulus energy necessary to elicit a sensory response.	Sensory Threshold,Threshold, Sensory,Thresholds, Sensory
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D014792	Visual Acuity	Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.	Acuities, Visual,Acuity, Visual,Visual Acuities
D015349	Vision, Monocular	Images seen by one eye.	Monocular Vision,Monovision