The document discusses binocular single vision, defining it as the coordinated use of two eyes to produce a single perception. Key concepts include simultaneous macular perception, fusion, and stereopsis, with explanations of sensory and motor fusion, monocular depth cues, and retinal correspondence. Investigations such as Bagolini's striated glasses and Worth's four dot test are mentioned, along with conditions like fixation disparity and retinal rivalry.

1. BINOCULAR SINGLE VISION:-
GOBIND SAH
INTERN
SANKARA NETHRALAYA,
KOLKATA.
MODERATOR:-
MISS DEBJANI ROY.
CHAIRPERSON:-R.VENKATARAMANAN

2. Binocular Single Vision:-
Binocular vision may be defined as the
coordinated use of two eyes to produce
a single mental impression.

3. Grades:-
 Given by William Worth in 1900
 Simultaneous Macular perception
 Fusion
 Stereopsis

4. Simultaneous macular perception:
It is defined as the ability of the two eye to
see two dissimilar objects simultaneously
and to superimposed them. It is tested by p
rojecting two dissimilar objects in front of th
e two eyes.
 Ex: Rabbit & Cage

6. Fusion:-
 It implies the ability of the two eyes to
superimpose two incomplete but similar
object to form the complete single image. It
is also tested by projecting two incomplete
but similar object in front of the two eyes.

8. Components Of Fusion:-
 Sensory Fusion- Unification of visual
excitations from corresponding retinal
images into a single visual percept.
 Motor Fusion-The ability to align the eyes
in such a way that sensory fusion can be
maintained.

9. Stereopsis:-
 It implies the ability of two eyes to obtain
an impression of depth by the
superimposition of two picture of the object
which has been taken from slightly
different angle.

11. Monocular Clues For
Depth Perception:-
 These are some information which helps a
monocular person to perceive depth,these are:-
1) Motion parallax
2) Overlay of contours
3) Linear perspective
4) Distribution of highlights & shadows
5) Aerial perspective
6) Size of known objects
7) Distance from horizon

13. Psychophysics and sensory
Aspects of binocular vision:-
 Visual direction and visual space
 Corresponding points and normal retinal
correspondence
 Horopter
 Physiological diplopia
 Concept of panum’s area
 Fixation disparity

14. Visual direction:-
 It refers to a line that joins the fixation object to
the center of fovea.Each point of retina has its
on particular visual direction.
Visual space:-
It refers to localization of any objects in the visual
system,It is also called as subjective space.

15. Retinal Correspondence:-
 Every retinal point or area has a partner in
the fellow eye with which it can shares a
common subjective visual direction.
 These two retinal elements are
corresponding retinal points.
 All other retinal elements are called non –
corresponding or disparate retinal points.

16. Types:-
 Normal Retinal Correspondence
 Abnormal Retinal Correspondence

17. Normal Retinal Correspondence:-
 when both the fovea have a common
visual direction and the retinal elements
nasal to the fovea in one eye and the other
eye have retinal elements temporal to the
fovea is called normal retinal
correspondence.

18. Abnormal Retinal
Correspondence:-
 When the fovea of one eye has a common
visual direction with an extra foveal area in
the other eye.
 ARC may develop throughout the first
decade of life.

19. Types:-
 Harmonious ARC-If the angle of anomaly
is equal to the angle of strabismus.
 Unharmonious ARC-If the angle of
anomaly is less than the angle of deviation.

20. Investigations Of ARC
 Bagolini’s striated glasses
 Worth’s four dot test
 Synaptophore

21. Bagolini’s striated glasses
 Normal response
 Homonymous diplopia
 Heteronymous diplopia

22. Worth four dot test
 Normal response
 Homonymous diplopia
 Heteronymous diplopia

23. Horopter:-
 The locus of all object points that are
imaged on corresponding retinal elements
at a given fixation distance is called
horopter.

25. Panum’s Fusional Area:-
 When a horopter is determined
experimentally,it is found that an object
may be located a certain distance in front
or behind without producing diplopia or
expected diplopia doesn’t occur then is
known as panum’s fusional area.

27. Fixation Disparity:-
 A condition in which the image of a
bifixated object do not stimulate exactly
corresponding point,But which still fall
within panum’s areas, the object thus
being seen single this is called fixation
disparity.

28. •The conflict which result when contradictory
and incompatible signals are transmitted from
corresponding points to the visual cortex is
called retinal rivalry.
If dissimilar contours are presented to
corresponding retinal points fusion is impossible.
Retinal Rivalry