Chapter 3 Sensation and Perception

Question 1

Sensation

Answer 1

The response of sensory receptors in the sense organs of stimulation and the transmission of that information to the brain

Question 2

The Retina

Answer 2

Thin membrane lining back of the eyeball; Contains the sensory receptors for vision, the rods and cones

Question 3

Photoreceptors

Answer 3

Sensory receptors cells that respond to light. Rods and cones are examples

Question 4

Rods and Cones

Answer 4

Rods cells are much more sensitive to light than cones. Cones cells are sensitive to the different wavelengths that produce the sensation of color. Cones cells are also specialized for seeing fine details.

Question 5

Fovea

Answer 5

Most of the cones are concentrated in the fovea, which is a region in the very center of the retina.

Question 6

Optic Nerve and the blind spot

Answer 6

Optic Nerve - The thick nerve that exits from the back of the eye and carries visual information to the visual cortex in the brain.
The blind spot - The point at which the optic nerve leaves the eye, producing a small gap in the field of vision.

Question 7

Structure of the eye

Answer 7

Cornea, Iris,, Pupil, Lens, Retina, Fovea

Question 8

Color Vision

Answer 8

Color vision is the ability of an organism or machine to distinguish objects based on the wavelengths (or frequencies) of the light they reflect, emit, or transmit.

Question 9

Additive Color Mixture

Answer 9

There are 3 primary colors. RGB. When combined, they become white.

Question 10

Trichromatic Theory of Color Vision

Answer 10

Human eyes can only detect 3 colors. Red, Green, and Blue. When a color other than those strike the retina, it will stimulate a combination of cones.

Question 11

Afterimages

Answer 11

Afterimage is the visual experience that occurs after the original source of stimulation is no longer present.

Question 12

Opponent-Process Theory of Color Vision

Answer 12

There are four basic colors which are dvided into two pairs of color-sensitive neurons: red-green and blue-yellow. Each pair can only stimulate one of the other, not both. If you stare at a green, black, yellow flag, it will produce an after image of red/white/blue.

Question 13

Sound Waves

Answer 13

Physical Stimuli that produce our sensory experience of sound.

Question 14

Frequency

Answer 14

The rate of vibration, or the number of sounds waves per second

Question 15

Amplitude

Answer 15

The intensity or amount of energy of a wave, reflected in the height of the wave; the amplitude of a sound wave determines a sound’s loudness

Question 16

The purpose of the structures in the ear

Answer 16

Sound waves are collected in the outer ear, amplified in the middle ear, and transduced or transformed into neural messages, in the inner ear

Question 17

Outer Ear

Answer 17

Includes the pinna, the ear canal, and the eardrum. The pinna catches sound waves and funnels them into the ear canal. The ear canal leads to the ear drum vibrates which matches the the vibration of the sound wave in intensity and frequency

Question 18

Middle Ear

Answer 18

Includes 3 bones: the hammer, anvil, and stirrup. The middle ear almost doubles the amplification of the sound

Question 19

Inner Ear

Answer 19

The oval window membrane separates the middle and inner ear. Cochlea is a fluid filled tube which ripples and gets transmitted to the basilar membrane.

Question 20

Basilar Membrane

Answer 20

The basilar membrance contains sensory receptors for sound called hair cells. The hair cell stimulates the cells in the auditory nerve which carries the neural information to the thalamus and auditory cortex of the brain

Question 21

Top-down vs bottom-up processing

Answer 21

Top-down processing (conceptually driven processing) - Drawing on our knowledge, experiences, expectations, and other cognitive processes to arrive at meaningful perceptions, such as people or objects in a particular context.
Bottom- up processing (data-driven processing) - The flow of sensory data from the sensory receptors to the brain. Trying to figure out the final picture based on ambiguous stimulus.

Question 22

Perceptual Organization

Answer 22

Our minds have a tendency to organized things in a preferred manner:
Proximity
Similarity
Closure
Figure vs. ground
Simplicity

Question 23

Gestalt Psychologists

Answer 23

Gestalt psychology proposes a unique perspective on human perception. According to Gestalt psychologists, we don’t just see the world, we actively interpret what we see, depending on what we are expecting to see.

Question 24

Figure and Ground

Answer 24

When we vie a scene, we automatically separate the elements of that scene into the figure, which is the main element of the scene, and the ground, which is its background. Example is finding a shape which is part of a white background

Question 25

Depth Perception

Answer 25

The use of visual cues to perceptive the distance of three-dimensional characteristics of objects

Question 26

Depth Perception Cues

Answer 26

Relative size - larger objects seem closer
Overlap - the blocked object is farther away
Aerial perspective - faraway objects appear blurred
Texture gradient - surface texture becomes less defined
Linear perspective - parallel lines seem to meet in a distance

Question 27

Monocular

Answer 27

Require only one eye for depth perception

Question 28

Binocular

Answer 28

Requires information from two eyes to determine depth.
Convergence - more eye strain means closer
Binocular disparity - if each eye sees it differently, it means it is closer

Question 29

Ames Room

Answer 29

As a result of the optical illusion, a person standing in one corner appears to the observer to be a giant, while a person standing in the other corner appears to be a dwarf.
It is sufficient to create an apparent horizon (which in reality will not be horizontal) against an appropriate background, and the eye relies on the apparent relative height of an object above that horizon.

Question 30

Muller-Lyer Illusion

Answer 30

The perception of a line can change by adding additional lines which cause the line to appear shorter or longer.

Question 31

Ponzo Illusion

Answer 31

The human mind judges an object’s size based on its background. He showed this by drawing two identical lines across a pair of converging lines, similar to railway tracks.

Question 32

Binocular Disparity

Answer 32

Seeing the difference in relative position in each eye. The closer it is the more disparity.

Question 33

Binocular Stereopsis

Answer 33

The perception of depth and 3-dimensional structure obtained on the basis of visual information deriving from two eyes by individuals with normally developed binocular vision

Question 34

Stereogram

Answer 34

A picture that uses the principle of binocular disparity to create the perception of a three-dimensional image.

Question 35

Autostereogram

Answer 35

A single image that depicts a three-dimensional image

Question 36

Perceptual constancy and set

Answer 36

Perceptual constancy - The tendency to perceive objects, especially familiar objects, as constant and unchanging despite changes in the sensory input. I.E. SUV stays the same size even though it really does get smaller as it drives away.

Perceptual set - The tendency to perceive objects or situations from a particular frame or reference. I.E. People into UFO’s might think of clouds as a UFO.