Flashcards in Chapter Nine - Knowledge Deck (113):
1
Conceptual Knowledge
knowledge that enables us to recognize objects + events
-make inferences about their properties
2
Concept
-mental representation used for a variety of cognitive functions
3
Categorization
process by which things are placed into groups
4
What are categories?
all possible examples of a particular concept
5
Concepts provide ______ for categories
the rules
6
Why are categories useful?
-helpful to understand individual cases not previously encountered
-"Pointers to knowledge"
7
How are categories pointers to knowledge?
-categories provide a wealth of general information about an item
-allow us to identify the special characteristics of a particular item
8
How do we determine category membership?
-whether object meets definition of the category
9
What is family resemblance?
-proposed idea to address problem that definitions often do not include all members of a category
10
How does family resemblance relate to categorization?
-things in a category resemble one another in another of ways
-allows for some variation within a category
11
Categorization may be based on _____
determining how similar an object is to some standard representation of a category
12
What is a prototype
-typical
-average representation of the typical member of cate
13
Prototype approach to categorization
-membership in a category is determined by comparing the object to a prototype that represents the category
14
What is an example of the prototype approach?
-not all birds are like robins, blue jays, or sparrows
-owls and penguins are also birds
15
Who is Rosch?
What was his experiment?
-prototype experiment
-S saw a category title (ex birds) + list of ~50 members of the category
-S asked to rate extent to which each member represented category title
16
What is high-prototypicality?
-category member closely resembles category prototype
-"tytpical" member
EX: "bird" = robin
17
What is low-prototypicality?
-category member does not closely resemble category prototype
EX: "bird" = penguin
18
What did Rosch and Mervis's experiment test?
-test how well do good + poor examples of category compare to to other items within the category
19
How did Rosch and Mervis's experiment work?
-for each common object, list as many characteristics/attributes
20
What does it mean when items have a large amount of overlap with characteristics of other items in the category?
-family resemblance of these items is high
EX: good examples of furniture = chair, sofa
poor examples = mirror
21
There is a strong positive relationship between _____ and _______
-prototypicality, family resemblance
22
What does low overlap between items mean?
-low family resemblance
23
What is the typicality effect?
-prototypical objects are processed preferentially
24
How are highly prototypical objects judge?
-more rapidly
EX: sentence verification technique
an apple is a fruit (y/n)
a pomegranate is a fruit (y/n)
25
What type of objects are named first?
-prototypical objects
26
What happens when asked to list as many objects in a category as possible?
-tend to list most prototypical members first
27
What are prototypical category members more affected by?
-a priming stimulus
28
How does a priming stimulus work?
-S heard the prime (ex: green)
-two seconds later: saw pair of colors side by side
-asked to press a key as quickly as possible if two were the same
-hearing "green" primes a highly prototypical green
29
What is the exemplar approach? (2)
1. concept represented by multiple examples
(rather than a single averaged prototype)
2. examples are actual category members
30
How do you categorize according to the exemplar approach?
-compare new item to stored examples
-this approach can explain Rosch results
31
How is the exemplar approach similar/disimilar to the prototype view?
similar: representing a category is not defining it
different: representation is not abstract (descriptions of specific examples)
32
What effect does the exemplar approach explain?
-typicality effect
33
How does the exemplar approach take into account atypical cases?
-rather than comparing a penguin to an "average" bird
-remember that there are birds that don't fly
34
Exemplars may work best for _____ categories
Prototypes may work best for _____ categories
-small
-larger
35
What does Rosch's research indicate about categories?
-different levels of categories
-from general ("furniture") to specific ("kitchen table")
36
What are the three levels of categories?
1. superordinate level (global level): "furniture"
2. basic level: "table"
3. subordinate level (or specific level): "kitchen table)
37
What is hierarchical organization?
-organization in which large/more general categories are divided into smaller, more specific categories
38
What was Rosch's experiment about levels of categorization?
-S were asked to list as many features as they could that would be common to all/most objects in category
39
What is the result of going above basic level results?
large loss of information
40
What is the result of going below basic level?
little gain of information
41
The basic level is ____ special
psychologically
42
How is the guitar/fish example evidence that the basic-level is special?
-when S asked to name a guitar and a fish
-named them by their basic level name
-guitar rather than electric guitar (specific) or musical instrument (global)
-fish rather than trout/animal
43
How does culture paly into the results of Rosch's experiment?
-there is a category level (called basic"
-reflects college undergraduates' everyday experience
44
What was Coley, Medin + Atran's experiment?
-asked both undergraduates + horticulturists to walk around campus
-name as specifically as possible 44 different plants
45
What was the result of the Coley, Medin + Atran experiment?
-75% of undergrads used trees
-horticulturalists used "specific" categories like "oak"
46
What was Tanaka and Taylor's experiment?
-asked bird experts + non-experts to name pictures of objects
47
What were the results of the Tanaka/Taylor experiment?
-experts responded by specifying the birds' species
-experts learned to pay attention to features of birds than non-experts were unaware of
48
What are 2 important factors in categorization?
1. people's knowledge
2. properties of objects
49
What are semantic networks?
-concepts are arranged in networks that represent the way concepts are organized in the mind
50
What did Collins and Quillian develop?
-model for how concepts + properties are associated in the mind
-hierarchical model (more specific to more general)
51
What is a node?
category/concept
52
What is inheritance?
-lower-level items share properties of higher-level items
53
What is the cognitive economy?
-shared properties are only stored at higher-level nodes
54
_____ are stored at lower level nodes
exceptions
55
according to the hierarchical organization, which concepts are at the top and which are the bottom?
-general concepts at the top
-specific ones at the bottom
56
What is a testable prediction?
-time it takes for a person to retrieve information about a concept should be determined by the distance that it must be traveled through the network
EX: takes longer to answer "yes" to a canary is an animal, compared to canary is a bird
57
What is activation?
arousal level of a node
58
What happens when a node is activated?
-activity spreads out along all connected links
59
What happens to concepts that receive activation?
-primed and more easily accessed from memory
60
What is the Lexical decision task/
-participants read stimuli
-asked to say as quickly as possible whether the item is a word or not
61
What were the results of Meyer and Schvaneveldt's lexical decision task?
-reaction time was faster for pairs that were closely associated
-spreading activation
62
What is a criticism of Collins and Quillian?
1. cannot explain typicality effects
EX: model predicts equal fast RT for both canary and ostrich as they are one node away from bird
2. evidence that people store specific properties of concepts right at the node for the concept
3. some sentence-verification results are problematic for the model
63
What is the typicality effect?
reaction times for statements about an object are faster for more typical members of a category
64
What are new approaches to the semantic network due to?
1. criticism of semantic networks
2. advances in understanding how information is represented in the brain
65
What is connectionism?
-approach to creating computer models for representing cognitive processes
66
What is connectionism also called?
-parallel distributed processing
-knowledge represented in the distributed activity of many units
67
______ determine at each connection how strongly an incoming signal will ________
weights, activate the next unit
68
(connectionist approach)
what are lines?
connections that transfer information between units (axons)
69
(connectionist approach)
what are output units?
-receive input from hidden units
70
(connectionist approach)
what are units
-inspired by neurons in the brain
-patterns of activity in units represent concepts + their properties
71
(connectionist approach)
what are input units?
units activated by stimuli from the environment
72
(connectionist approach)
what is connection weight?
-how signals sent from one unit either increase/decrease the activity in the next unit
73
What are high connection weights?
-result in strong tendency to excite the next unit
74
What are the 5 aspects of the connectionist approach?
1. lines
2. connection weight
3. units
4. output units
5. input units
75
What are negative connection weights?
-can decrease excitation
-or inhibit activation of the receiving unit
76
What are the 2 things the activation of units depends on?
1. signal that originates in the input units
2. the connection weights throughout the network
77
How is a stimulus represented according to the connectionist approach?
-by the pattern of activity that is distributed across the other units
78
What is the learning process for the connection approach?
-connection weights have to be adjusted in order for the network to operate properly
79
How does learning occur in the connectionist approach? (3)
1. network responds to stimulus
2. provide with correct response
3. modifies responding to match correct response
80
What is error signal?
-difference between actual activity of each output unit + correct activity
81
What is back propagation?
-error signal transmitted back through the circuit
82
What is the purpose of error signal?
-indicates how weights should be changed to allow the output signal to match the correct signal
83
The process ____ until the error signal is _____
repeats, zero
84
What is the initial state of the units in the connectionist approach?
-initially weak and undifferentiated activation of property units
-with many errors
85
What is the process of error signal in the connectionist approach? (3)
1. error signals are sent back
2. changes are made in connection weights
3. each learning ex. causes only a small change in the connection weights
86
What happens in connectionist networks?
-information about each concept is contained in distributed pattern of activity
-across a number of units
87
Is the operation of connectionist networks totally disrupted by damage?
-no
88
what is graceful degradation?
disruption of performance occurs gradually as parts of the system are damaged
89
How can connectionist networks explain generlization of learning?
-similar concepts have similar patterns
-training a system to recognize the properties of one concept also provides info about other related concepts
90
How can different areas of the brain be specialized to process info about different categories?
1. double dissociation for categories
EX: "living things" and "nonliving things"
2. category specific memory impairment
91
What is the sensory-functional hypothesis?
-our ability to differentiate living things + artifacts depends on semantic memory system
-distinguishes sensory attributes + function
92
What does the Sensory-functional hypothesis predict about a patient who can't identify living things?
they should have impaired sensory abilities
93
What did Caramazza + Shelton find about the sensory functional hypothesis?
-reported a patient who couldn't identify living things
-impaired sensory memory
-also had impaired functional ability
(contradicts (S-F hypothesis)
94
What does the sensory-functional hypothesis predict about a person who can't identify artifacts
should have impaired functional knowledge
95
What did Ralphs find about the sensory functional hypothesis?
-reported a patient who couldn't recognize artifacts
-had impaired sensory ability
96
There are specific ____ in the brain for specific categories
neural circuits
97
How are neural circuits arranged in the brain for specific categories?
-distributed over a number of different cortical areas
98
Why might there be a limited number of categories that are innately determined?
because of their importance for survival
99
What did Wilmer et. al test?
-the idea that there may be a limited number of categories that are innately determined because of their importance for survival
100
How did Wilmer run his experiment?
-measuring face recognition ability in mozygotic + dizogotic twins
101
What were the results of Wilmer's facial recognition experiment?
-correlation of scores between identical twins was more than twice as high as the other group
-there may be a genetic basis for the mech involved in face recognition
102
What is the multiple factors approach?
-looks at how concepts are divided up within a category
-rather than identifying specific brain areas of networks for different concepts
103
Mechanical devices (EX: musical instruments) overlap with:
-artifacts (involve performing actions)
-animals (involve sound and motion)
104
How do mechanical devices have a widely distributed semantic representation?
-regions important for the representation of both living things and artifacts
105
patients may be able to identify mechanical devices even if _____
they perform poorly for other types of artifacts
106
What is another differentiating factor between animals and artifacts?
-crowding
107
What is crowding?
when different concepts within a category share many properties
EX: "animals" all share "eyes," "legs," "ability to move"
-artifacts share fewer properties
108
Why might patients with category-specific impairments not have a category impairment at all?
-patients may have difficulty recognizing living things because they have difficulty distinguishing between items that share similar features
109
What is the embodied approach?
-our knowledge of concepts is based on reactivation of sensory + motor processes that occur when we interact with the object
110
What is an example of the embodied approach?
-when we use a hammer:
-different sensory areas are activated due to hammer's size/shape etc.
-motor areas are activated that are involved in carrying out actions involved in using a hammer
-interaction between action and perception
111
What are mirror neurons?
-neurons that fire when we do a task or when we observe another doing that same task
112
How do mirror neurons connect to the embodied approach?
-thinking about concepts causes activation of perceptual and motor areas associated with the concepts
113