Seeing

Question 1

Accommodation

Answer 1

Helps determine depth.

Question 1

Beta effect

Answer 1

The perception of motion that occurs when different images are presented next to each other in succession

Question 2

Binocular depth cues

Answer 2

Depth cues that are created by retinal image disparity — that is, the space between our eyes — and which thus require the coordination of both eyes

Question 3

Blind spot

Answer 3

A hole in our vision because there are no photoreceptor cells at the place where the optic nerve leaves the retina

Question 4

Colour blindness

Answer 4

The inability to detect green and/or red colours

Question 5

Cones

Answer 5

Visual neurons that are specialized in detecting fine detail and colours

Question 6

Convergence

Answer 6

The inward turning of our eyes that is required to focus on objects that are less than about 50 feet away from us

Question 7

Cornea

Answer 7

A clear covering that protects the eye and begins to focus the incoming light

Question 8

Depth cues

Answer 8

Messages from our bodies and the external environment that supply us with information about space and distance.

Question 9

Electromagnetic energy

Answer 9

Pulses of energy waves that can carry information from place to place

Question 10

Farsighted

Answer 10

When the focus is behind the retina

Question 11

Feature detector neurons

Answer 11

Specialized neurons, located in the visual cortex, that respond to the strength, angles, shapes, edges, and movements of a visual stimulus

Question 12

Fovea

Answer 12

The central point of the retina

Question 13

Gestalt

Answer 13

A meaningfully organized whole

Question 14

Hue

Answer 14

The shade of a colour

Question 15

Iris

Answer 15

The coloured part of the eye that controls the size of the pupil by constricting or dilating in response to light intensity

Question 16

Lens

Answer 16

A structure that focuses the incoming light on the retina

Question 17

Monocular depth cues

Answer 17

Depth cues that help us perceive depth using only one eye

Question 18

Nearsighted

Answer 18

When the focus is in front of the retina

Question 19

Opponent-process colour theory

Answer 19

Proposes that we analyze sensory information not in terms of three colours but rather in three sets of “opponent colours”: red-green, yellow-blue, and white-black

Question 20

Optic nerve

Answer 20

A collection of millions of ganglion neurons that sends vast amounts of visual information, via the thalamus, to the brain

Question 21

Phi phenomenon

Answer 21

We perceive a sensation of motion caused by the appearance and disappearance of objects that are near each other

Question 22

Pupil

Answer 22

A small opening in the centre of the eye

Question 23

Retina

Answer 23

The layer of tissue at the back of the eye that contains photoreceptor cells

Question 24

rods

Answer 24

Visual neurons that specialize in detecting black, white, and gray colours

Question 25

Trichromatic colour theory

Answer 25

The colour we see depends on the mix of the signals from the three types of cones

Question 26

Visible spectrum

Answer 26

The part of the electromagnetic spectrum that our eyes detect (only the range from about 400 to 700 billionths of a meter)

Question 27

Visual accommodation

Answer 27

The process of changing the curvature of the lens to keep the light entering the eye focused on the retina

Question 28

Visual cliff

Answer 28

A mechanism that gives the perception of a dangerous drop-off, in which infants can be safely tested for their perception of depth

Question 29

Wavelength

Answer 29

The distance between one wave peak and the next wave peak References