Lecture 7: Vision

Question 1

The eyeball consists of a _____ which focuses light onto a sheet of cells called the ______

Answer 1

Lens; Retina

Question 2

What is the major differences between rods and cones?

Answer 2

Rods: detect low light levels
Cones: color and detail resolution

Question 3

What are the ways that rods and cones are distinguished? (4)

Answer 3

Shape, photopigment, retina distribution, synaptic connections

Question 4

What is the relationship between acuity and receptor/receptive field size?

Answer 4

Smaller receptors are able to more accurately localize visual features in space

Question 5

There are more _____ than ______ in center of retina (fovea)

Answer 5

Cones; Rods

Question 6

Arises because of the “cables” leaving the eyeball, different parts of the visual field in each eye and the brain guess what might be in its location

Answer 6

The Blind Spot

Question 7

Photopigment in rods made up of opsin and retinal

Answer 7

Rhodopsin

Question 8

Occurs as the feedback from the interneurons, horizontal cells and amacrine cells, which receive excitatory inputs from photoreceptors

Answer 8

Lateral Inhibition

Question 9

When several photoreceptors connect with a few bipolar neurons which connect with a single ganglion cell, occurs more in the periphery than the fovea

Answer 9

Convergence

Question 10

The bipolar cells and retinal ganglion cells ______ so that more light reaches the photoreceptors at the fovea

Answer 10

Bend

Question 11

In the retina bipolar cells respond with ______ while ganglion cells respond with ______

Answer 11

graded potentials; action potentials

Question 12

Occurs when an excited neuron reduces the activity of its neighbors, enhances sensory perception and makes images sharper

Answer 12

Lateral Inhibition

Question 13

The mind can only register the presence of one color of a pair at a time because the two colors oppose one another

Answer 13

Opponent Process Theory of Color Perception