chapter 4: perception

Question 1

what is the difference between sensation and perception

Answer 1

sensation: conversion of physical properties of the world or body into a neural code by the PNS
perception: processing and interpretation of sensory information into a form that is useful for a behavioral decision

Question 2

perception takes place in the … in the nervous system
a. spinal cord
b. sensory receptors
c. motor neurons
d. brain

Answer 2

d. brain

Question 3

define exteroception

Answer 3

the sensing and processing of information from the external environment through the five basic senses

Question 4

define interoception

Answer 4

sensing and processing of stimuli inside the body

Question 5

differentiate proprioception, nociception and equilibrioception

Answer 5

proprioception: sense of where in space our limbs are
nociception: sense of pain due to bodily damage
equilibrioception: sense of balance

Question 6

when entering the eye, name the components light goes through

Answer 6

focused by the cornea
enters through small opening in the iris, called pupil
focused more by the lens
travels to retina

Question 7

name the two types of photoreceptors in the retina

Answer 7

rods and cones

Question 8

which photoreceptors are better for seeing under lower lighting and have reduced resolution

Answer 8

rods

Question 9

how come rod vision is color blind

Answer 9

all rods respond equally to different wavelengths of light

Question 10

what is called the center of the retina

Answer 10

fovea

Question 11

why is it necessary to compress the amount of information that the retina needs to send to the brain

Answer 11

can restrict the movement of the eye if optic nerve is too fat. since it passes through retina, it can restrict the number of photoreceptors that the retina can contain

Question 12

what is the role of the thalamus

Answer 12

way-station between sensory inputs and cortex

Question 13

which of the following categories would neurons at the lowest level of the visual stream likely be selective for?
a. specific shapes
b. oriented edges
c. spots of light
d. specific objects and faces

Answer 13

c. spots of light

Question 14

define prosopagnosia

Answer 14

marked difficulty in recognizing individual faces. no general visual or memory difficulties but can’t identify whose face it it

Question 15

what is semantic agnosia

Answer 15

can recognize faces, but not everyday objects.

Question 16

when is the lateral occipital cortex (LOC) more active

Answer 16

when people engage in object recognition tasks

Question 17

describe the greebles study and the conclusion that was pulled from it

Answer 17

participants had difficulty discriminating between visually similar Greebles. After a while, they became proficient. The Greebles activated the FFA, just as faces do
Conclusion: FFA is specialized for visual “expertise” not for faces

Question 18

what are the two different visual streams and which aspects do they process

Answer 18

ventral stream processes the “what” aspects
dorsal stream processes the “where” aspects

Question 19

what are the five basic taste receptors types

Answer 19

sweetness, sourness, saltiness, bitterness, savoriness

Question 20

True or false? In gustation, the sensory neurons send their signal through the spinal cord

Answer 20

false, they send it through the brainstem

Question 21

what is the olfactory epithelium

Answer 21

strip of tissue in nasal cavity that contains tens of millions of chemical sensory receptors

Question 22

in the olfactory system, to which part of the brain do sensory neurons send transduced chemical information to

Answer 22

the olfactory bulb

Question 23

in order, what are the structures sound goes through when it enters the ear

Answer 23

pinna captures
ear canal amplifies
ear drum amplifies
ossicles relay
cochlea contains fluid
basilar membrane containing hair cells vibrate

Question 24

hair cells at the … starting point respond to … frequency sound, hair cells at the … starting point respond to … frequency sound
a. outer; high; inner; lower
b. outer; low; inner; high

Answer 24

a. outer; high; inner; lower

Question 25

in which lobe is the primary auditory cortex situated

Answer 25

temporal lobe

Question 26

what are sound waves

Answer 26

oscillating movement in the air caused by vibrations of objects in the environment

Question 27

what are the two properties of sound waves

Answer 27

frequency: distance between crests of waves amplitude: height from trough to crest of wave

Question 28

which cortex of the brain receives sensory information from all across the body and in which lobe is it located

Answer 28

somatosensory cortex in the temporal lobe

Question 29

what is the cortical homunculus

Answer 29

spatially organized map of the human body that processes touch information

Question 30

what is the constructivist theory of perception

Answer 30

use of sensory information to generate a mental model of the environment that would have caused the sensory stimulus

Question 31

what is the direct model of perception

Answer 31

approach to perception that holds that the sensory stimuli guides behavior/action in a continuous perception/action loop

Question 32

when a material absorbs a lot of light, how does it affect how the material is perceived? a. it will appear light b. it will appear dark c. it will appear colorful d. it will lack color

Answer 32

b. it will appear dark

Question 33

what do illusions reveal about the assumptions that the brain makes during perception a. perception is not as useful as sensation b. these assumptions are usually incorrect c. perception often depends on guesses d. our brains cannot be tricked

Answer 33

c. perception often depends on guesses

Question 34

define the bi-stable property

Answer 34

property of a stimulus that has alternating stable perceptual interpretations

Question 35

define bottom up processing

Answer 35

processing that does not require any specific knowledge of the stimulus

Question 36

define top-down processing

Answer 36

processing where we leverage knowledge or expectations that are not in the sensory stimulus itself

Question 37

define phonemic restoration effect

Answer 37

brain "filling in" missing sounds from a speech signal, based on expectations about which sounds belong in that portion of speech

Question 38

define image segmentation

Answer 38

brain's ability to divide up the image into different objects and regions

Question 39

what is figure-ground assignment

Answer 39

determinating which side of the boundary contains the shape and the background

Question 40

what are the three figure-ground clues and why

Answer 40

convexity: figures tend to have convex shape symmetry: figures usually display bilateral symmetry smaller region: figures are usually smaller than background

Question 41

define visual grouping

Answer 41

combining spatially separate regions into unified wholes

Question 42

according to the Gestaltists, what are the three grouping cues and explain them

Answer 42

law of similarity: tendency to group features that have similar properties law of proximity: tendency to group features that are close together law of good continuation: tendency to group features to form a smooth, continuous path rather than one with a sharp discontinuity

Question 43

what is the function of depth perception

Answer 43

figuring out how far an object is away from you to interact with it and determines its shape

Question 44

name the cues to depth perception

Answer 44

- object that occlude other objects are assumed to be in front - motion parallax: objects farther away will change their position more slowly on your retina as you move - binocular disparity: the image on each two eye is different

Question 45

what is stereopsis

Answer 45

the use of binocular disparity to perceive depth. the higher in depth, the higher disparity. the lower in depth, the lower disparity

Question 46

what aspects of having two eyes may be used to perceive depth a. image features will have different sizes in the two retinas b. image features will fall on the same locations in the two retinas c. image features will have the same sizes in the two retinas d. image features will fall on different locations in the two retinas

Answer 46

d. image features will fall on different locations in the two retinas

Question 47

what is the template model of recognition

Answer 47

matching an object to an image stored in memory

Question 48

why are template models abject failures when trying to recognize objects in the real world

Answer 48

because every time you view an object, the image it produces on your retina is different due to external factors (depth, lighting, viewpoint)

Question 49

differentiate these two types of recognition: identification and classification

Answer 49

identification: ability to identify the same object or person across variations classification: determining whether a given image corresponds to a class or category

Question 50

define scene schema

Answer 50

learned representation of which objects tend to appear in specific kinds of scenes

Question 51

true or false? recognition does not require top-down processing

Answer 51

false, the use of past experience to make inferences about current sensory information provides a context which affects recognition

Question 52

define synaesthesia

Answer 52

neurological condition in which one sense automatically triggers the experiences of another sense

Question 53

describe the early visual process

Answer 53

1. light waves enter the eye and are projected onto the retina 2. photoreceptors in retina convert light to electrical activity 3. electrical signal is sent to bipolar cells then ganglion cells 4. signal exits through optic nerve to brain

Question 54

why do we not 'see' our blindspot

Answer 54

- perceptual filling-in - left and right visual field compensate for each other's blindspot

Question 55

what is the function of the visual association area

Answer 55

interprets visual information and assigns meaning

Question 56

define akinetopsia

Answer 56

visual motion blindness: cannot see motion. perceives motion as a series of stationary objects

Question 57

define optic ataxia

Answer 57

inability to reach for objects with the ability to name objects

Question 58

what is the difference between apperceptive agnosia and associative agnosia

Answer 58

apperceptive: problems perceiving objects associative: problems assigning meaning or labelling objects

Question 59

what is the prototype theory

Answer 59

- recognition determined by a 'good enough' match (resemblance) - allows for 'flexible' object identification

Question 60

what are the two pathways that process different auditory information

Answer 60

dorsal: sound localisation ventral: sound properties