spatial localisation
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Assessment of Binocular Vision
Detection of Ocular Deviation
Strabismus?
Motility
Spatial Localisation
Spatial Localisation
Appreciation of spatial characteristics of environment
Judgements made relative to egocentre
Postural system relates to gravityVisual sense provides contact with
world
Spatial Localisation
Bi-dimensional localisationJudgement of direction
Tri-dimensional localisationJudgement of depth and distance
Bi-Dimensional Localisation
Position of image on the retina
Position of eye with respect to body
Visual organisation
Fovea has principle visual directionEach point on retina has a local signLocal sign is relative to fovea
Localisation
Position of image on the retina gives oculocentric localisation
Combination of oculocentric localisation and registration of eye position allows egocentric localisation
Oculocentric Localisation
Egocentric Localisation
Registration of eye position
Tri-Dimensional Localisation
Depth and distance
Monocular Cues
Motion ParallaxOver-lapping contoursRelative sizeLight and shadeAerial perspectiveGeometric perspectiveSurface texture
Over-lapping contours
Relative size
Light and shade
Aerial Perspective
Geometric perspective
Surface texture
Binocular Vision
Eyes (1982) Louise Bourgeois
Stereopsis
Binocular overlap
Binocularly coordinated eye movements
Partial decussation of afferent fibres
Common Visual Direction
Cyclopean Eye
Corresponding Points
Pairs of points on each retina share a common visual direction
A point on the nasal retina of one eye will have a corresponding point on the temporal retina of the other eye
Localised from cyclopean eyeLaw of sensory correspondence
Binocular Correspondence
Cyclopean Localisation
Physiological Diplopia
Summary
Many cues contribute to binocular perception
Binocular vision requires a highly developed visual system
Physiological diplopia is useful as a clinical tool
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