Binocular Vision

Question 1

visual perception

Answer 1

unconscious inference

• brain is always making inferences and constructing mental representations
• what you see is the most likely thing that could have created retinal image (illusion = when brain makes wrong inference/representation)

Question 2

why do humans have binocular vision?

Answer 2

• spare eye
• larger field of view
• stereoscopic depth perception
• seeing through occluding objects by suppressing what obstructed eye sees

Question 3

binocular summation

Answer 3

detecting/recognizing objects at low contrast (fog, night time, etc.)

Question 4

eye movements: version

Answer 4

eyes moving together (vertical and horizontal)

• smooth pursuit
• saccades

(conjugate EM)

Question 5

vergence

Answer 5

eyes converging (inward, crossed) or diverging (outward, uncrossed) (mostly horizontal)

(disconjugate EM)

Question 6

binocular disparities

Answer 6

eyes are separated in head, so they see slightly different views (eye wink demo)

• near objects = crossed disparity
• far objects = uncrossed disparity

Question 7

strabismus

Answer 7

Greek root word = “crooked”

• esotropia (inward) vs. exotropia (outward)
• intermittent = sometimes there

NOT esophoria or exophoria

Question 8

ACA

Answer 8

Accommodative Convergence from Accommodation

Question 9

why would a farsighted person have an eye turn?

Answer 9

• have to thicken eyes to accommodate but the eyes turn in

- eyes are too flat

Question 10

amblyopia

Answer 10

“blunt vision”

• reduced acuity in one (rarely both) eyes
• loss of binocular depth perception

usually caused by

• unilateral hyperopia
• strabismus
• unilateral form deprivation