Visual Flashcards
What does the visual system provide?
Sight
Processing of visual info for recognition and location of objects
Eye mvmt
Info used in postural and limb mvmt control
What is the role of the cornea?
Allows light to pass through
What is the role of the sclera?
Protection
What is the role of the aqueous humor?
Fluid protects cornea and lens
Is the cornea avascular
Yes
What is the role of the lens?
Refracts light onto the retina
Always changing curvature (dynamic structure)
What is the role of the iris?
Controls amount of light on the lens
What is the role of the ciliary muscle?
Controls the curvature of lens
What is the vitreous humor?
Clear gel
Let’s the light fall onto the retina
Why do we see “floaters”?
Light is further refracted by the vitreous humor
Gel in vitreous humor is not clear
Where do we want the light to fall?
Retina
What receptors are in the eye?
Photoreceptors
What is the most sensitive to light?
Fovea
What can we see with the fovea?
Color
Amount of light
Clarity of image
Where do we want the focal point to end up?
On the retina
What are the types of photoreceptors?
Rods
Cones
Which photoreceptors are MOST sensitive to light?
Rods
Which photoreceptors are important for nighttime vision?
Rods
Which photoreceptors are responsible for seeing color?
Cones
Examples of refractive errors?
Myopia
Astigmatism
Hyperopia
Presbyopia
What is a form of hyperopia due to aging?
Presbyopia
What is there is a cut at right optic nerve?
Blind in right eye
What if there is a cut at the optic chiasm?
Bitemporal hemianopia
What if there is a pituitary tumor on the optic chiasm?
Bitemporal hemianopia
What if there is a cut at the right optic tract?
Can’t see on the left eye
