Chapter6 Flashcards

1
Q

Sensitivity

A

The ability to detect the presence of dimly lit objects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Acuity

A

The ability to see the details of objects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Ciliary muscles

A

The eye muscles that control the shape of the lens.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Accommodation

A

The process of adjusting the configuration of the lenses to bring images into focus on the retina.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Binocular disparity

A

The difference in the position of the same image on the two retinas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Light

A

Waves of electromagnetic energy between 380-760 nanometers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Receptors

A

Cells that are specialized to receive chemical, mechanical, or radiant signals demo the environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Horizontal cells

A

Type of retinal neurons whose specialized function is lateral communication.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Bipolar cells

A

Bipolar neurons that form the middle layer of the retina.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Amacrine cells

A

A type of retinal neuron whose specialized function is lateral communication.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Retinal ganglion cells

A

Retinal neurons whose axons leave the eyeball and form the optic nerve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Blind spot

A

A gap in the receptor layer due to the optic nerve leaving the eyeball.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fovea

A

An indentation at the center of the retina that is specialized for high-acuity vision. The thinning of the retinal ganglion layer reduces distortion of incoming light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Completion

A

Filling in the blind spot with information provided by the receptors around the blind spot.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Surface interpolation

A

The process by which the visual system perceives large surfaces, by extracting information about edges and from it, inferring the appearance of adjacent surfaces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cones

A

The visual receptors of the retina that mediate high acuity color vision in good lighting.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Rods

A

The visual receptors of the retina that mediate achromatic, low acuity vision under dim light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Duplexity theory

A

The theory that cones and rods mediate different kinds of vision.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Photopic vision

A

Cone-mediated vision. Predominates in good lighting and provides high-acuity color perceptions of the world.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Scotopic vision

A

Rod-mediated vision. Predominates in dim illumination, there is not enough light to reliably excite cones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Nasal hemiretina

A

The half of each retina next to the nose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Temporal hemiretina

A

The half of each retina next to the temples.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Photopic spectral sensitivity curve

A

The graph of sensitivity of cone-mediated vision to different wavelengths of light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Scotopic spectral sensitivity curve

A

The graph of sensitivity of rod-mediated vision to different wavelengths of light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Purkinje effect

A

In intense light, red and yellow wavelengths look brighter than blue or green wavelengths of equal intensity; in dim light, blue and green wavelengths look brighter than red and yellow wavelengths of equal intensity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Fixation eye movements

A

Involuntary movements of the eyes that occur when a person tries to fix their gaze on a point (tremor, drifts, saccades)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Saccades

A

Small jerky movements or flicks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Transduction

A

The conversion of one form of energy to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Rhodopsin

A

The photopigment of rods. When exposed to intense light, it is bleached and looses its ability to absorb light. When returned to the dark, it regained its redness and ability to absorb light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Absorption spectrum

A

A graph of the ability of a substance to absorb light of different wavelengths.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Visual field

A

The entire area that you can see as a particular movement.

32
Q

Visual transduction

A

Conversion of light to neural signals by the visual receptors.

33
Q

Pigment

A

A substance that absorbs light.

34
Q

Retina-geniculate striate pathways

A

Conducts signals from each retina to the primary visual cortex/striate cortex via the lateral geniculate nuclei.

35
Q

Primary visual cortex/ striate cortex

A

The area of the cortex that receives direct input from the lateral geniculate nuclei.

36
Q

Lateral geniculate nuclei

A

The six-layered thalamic structures that receive input from the retinas and transmit their output to the primary visual cortex/ striate cortex.

37
Q

Retinotopic

A

Organized, like the primary visual cortex, according to a map of the retina. There is a disproportionate representation of the fovea.

38
Q

Parvocellular layers (P layer)

A

Particularly responsive to color, fine pattern details, and stationary or slow moving objects. Cones provide most of the input. Top four layers.

39
Q

Magnocellular layers (M layer)

A

Particularly responsive to movement. Rods provide most of the input. Bottom two layers.

40
Q

contrast enhacement

A

intensification of the perception of edges

41
Q

ommatidia

A

very large receptors interconnected by a lateral neural network

42
Q

lateral inhibition

A

receptors fires, it inhibits its neighbors via the lateral neural network

43
Q

receptive field

A

the area of the visual field within which it is possible for a visual stimulus to influence the firing of that neuron

44
Q

achromatic

A

uncolored light shone on the retina

45
Q

monocular

A

each neuron had a receptive field in one eye but not the other

46
Q

On-center cells

A

respond to lights shone in the central region of their receptive fields “on” firing and to lights shone in the periphery of their receptive fields with inhibition, followed by “off” firing when the light is turned off

47
Q

Off-center cells

A

respond with inhibition and “off” firing in response to lights in the center of their receptive fields and with”on” firing to lights in the periphery of their receptive fields

48
Q

simple cells

A

Neurons in the visual cortex that respond maximally to straight-edge stimuli in a certain position and orientation

49
Q

complex cells

A

Neurons in the visual cortex that respond optimally to straight-edge stimuli in a certain orientation in any part of their receptive field

50
Q

binocular

A

respond to stimulation of either eye

51
Q

Component theory (trichromatic theory)

A

theory that the relative amount of activity produced in three different classes of cones by light determines its perceived color

52
Q

opponent process theory

A

theory that a visual receptor or a neuron signals one color when it responds in one way (e.g., by increasing its firing rate) and signals the complementary color when it responds in the opposite way (decreasing firing rate)

53
Q

chromats

A

vision photopigments

54
Q

color constancy

A

refers to the fact that the perceived color of an object is not a simple function of the wavelengths reflected by it

55
Q

retinex theory

A

the color of an object is determined by its reflectance- proportions of light of different wavelengths that a surface reflects

56
Q

Dual-opponent color cells

A

Neurons that respond to the differences in the wavelengths of light stimulating adjacent areas of their receptive field

57
Q

cytochrome oxidase

A

an enzyme present in particularly high concentrations in the mitochondria of dual-opponent color cells of the visual cortex

58
Q

blobs

A

peglike, cytochrome oxidase-rich, dual-opponent color columns

59
Q

secondary visual cortex

A

those that receive most of their input from the primary visual cortex

60
Q

visual association cortex

A

areas that receive input from areas of secondary visual cortex as well as from the secondary areas of other sensory systems

61
Q

prestriate cortex

A

band of tissue in the occipital lobe that surrounds the primary visual cortex

62
Q

infrerotemporal cortex

A

cortex of the inferior temporal lobes

63
Q

posterior parietal cortex

A

areas of association cortex that receive visual input are located in several parts in several parts of the cerebral cortex–largest one

64
Q

scotoma

A

area of blindness in the the corresponding area of the contralateral visual field of both eyes

65
Q

perimetry test

A

The procedure used to map scotomas

66
Q

hemianopsic

A

have a scotoma covering half of their visual field

67
Q

conscious awareness

A

person sees something, he or she will be consciously aware of seeing it

68
Q

Blindsight

A

the ability of such patients to respond to visual stimuli in their scotomas even though they have no conscious awareness of the stimuli

69
Q

dorsal stream

A

flows from the primary visual cortex to the dorsal prestriate cortex to the posterior parietal cortex

70
Q

ventral stream

A

flows from the primary visual cortex to the ventral prestriate cortex to the inferotemporal cortex

71
Q

“where” versus “what” theory

A

vision is that damage to some areas of cortex may abolish certain aspects of vision while leaving others unaffected

72
Q

“control of behavior” versus “conscious perception” theory

A

Theory that the dorsal stream mediates behavioral interactions with objects and the ventral stream mediates conscious perception of objects

73
Q

Prosopagnosia

A

visual agnosia for faces

74
Q

agnosia

A

failure of recognition

75
Q

Fusiform face area

A

an area of human cortex, located at the boundary between the occipital and temporal lobes, that is selectively activated by human faces

76
Q

Akinetopsia

A

deficiency in the ability to see movement progress in a normal smooth fashion

77
Q

MT area

A

middle temporal area of the cortex