Psych 202: The Visual System

Question 1

Sensory receptors

Answer 1

A receptor that is directly affected by changes in in the environment

Question 2

Sensory transduction

Answer 2

The process of transferring stimuli into changes in the membrane potential

Question 3

Receptor potential

Answer 3

Change in membrane potential results in change in neurotransmitter released

Receptor cells lack an axon, so there is no action potential

Question 4

Eyeball anatomy

Answer 4

Conjunctiva - mucous membrane

Cornea - transparent outer layer

Pupil - hole regulated by contractions of the iris

Lens - transparent layer that focuses light on the retina

Question 5

Retinal anatomy

Answer 5

Photoreceptors - rods and cones

Fovea - region that contains only cones

Optic disk - location on the retina where axons exit the retina and enter the optic nerve

Question 6

Retinal cells function

Answer 6

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Question 7

Photoreceptors

Answer 7

Rods and cones

Rods - low light, black and white, low resolution, sensitive

Cones - lots of light, acute, color, high resolution

Question 8

Photopic system

Answer 8

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Question 9

Scotopic system

Answer 9

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Question 10

Photoreceptor adaptation

Answer 10

The tendency of rods and cones to adjust their light sensitivity to match ambient levels of illumination

Question 11

Bipolar cells (on-center & off-center)

Answer 11

A class of interneurons of the retina that receive information from the rods and comes and pass the information to the retinal ganglion cells

On center - excited by light in the center of its receptive field

Off center - inhibited by light in the center of its receptive field

Question 12

Horizontal cells

Answer 12

Specialized retinal cells that contact both the receptor cells and the bipolar cells

Question 13

Amacrine cells

Answer 13

Specialized retinal cells that contact boththe bipolar cells and the ganglion cells, and are especially significant in inhibitory interactions within the retina

Question 14

Ganglion cells (on-center & off-center)

Answer 14

A class of cells in th retina whose axons form the optic nerves

On center - a retinal ganglion cell that is activated when light is presented to the center, rather than the periphery of the cells receptive field

Off center - activated when light is presented to the periphery rather than the center of the cells receptive field

Question 15

Lateral inhibition

Answer 15

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Question 16

Accommodation

Answer 16

The process of focusing by the ciliary muscles and the lens to form a sharp image on the retina.

Question 17

Primary visual pathway

Answer 17

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Question 18

Optic nerve

Answer 18

The collection of ganglion cell axons that extend from the retina to the optic chaism

Question 19

Dorsal lateral geniculate nucleus

Answer 19

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Question 20

Retino-hypothalamic pathway

Answer 20

The projection of the retinal ganglion cells to the suprachiasmatic nuclei

Question 21

Retino-tectal pathway

Answer 21

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Question 22

Striate cortex (V1)

Answer 22

The region of the occipital cortex where most visual information first arrives

Question 23

Receptive field (concentric nature)

Answer 23

The stimulus region and features that affect the activity of a cell in a sensory system

Question 24

Orientation-sensitive neurons

Answer 24

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Question 25

Binocular vision

Answer 25

Using both eyes to see a scene

Question 26

Stereopsis

Answer 26

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Question 27

Retinal disparity

Answer 27

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Question 28

Ocular dominance

Answer 28

When one eye has a greater degree of synaptic input

Question 29

Cytochrome oxidase blobs

Answer 29

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Question 30

V1 modules

Answer 30

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Question 31

Extrastriate cortex

Answer 31

Visual cortex outside the primary visual cortex.

Question 32

Dorsal & ventral visual stream

Answer 32

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Question 33

Color perception

Answer 33

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Question 34

Form perception

Answer 34

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Question 35

Movement perception

Answer 35

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Question 36

Location perception

Answer 36

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Question 37

Mirror neurons

Answer 37

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Question 38

Visual agnosias

Answer 38

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Question 39

Scotoma

Answer 39

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Question 40

Blindsight

Answer 40

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Question 41

Evolution of the eye

Answer 41

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