CHAPTER 9 CONCEPTUAL KNOWLEDGE Flashcards
what is conceptual knowledge?
knowledge that enables us to recognize objects/events and to make inferences to their properties
what is a concept (1)
the mental representation of a class/individual
what is a concept(2)
categories of objects, events, and abstract ideas
what is a category?
all possible examples of a particular concept
what is categoriaztion?
the process by which things are placed in categories
describe the definitional approach to categorization
determining whether a particular object meets the definition of a category
what philosopher coined the term family resemblance to characterize similarities between objects?
Ludwig Wittgenstein
what is family resemblance?
refers to the idea that things in a particular category resemble one another in a number of ways
describe the prototype approach to categorization
when membership of a category is determined by comparing the object to a prototype of that category
what problem does family resemblance attempt to resolve?
definitions often do not include all members of a category
what is a prototype?
typical member of a category
who proposed a typical prototype is based on an average of members of a category that are commonly experienced
Elanor Rosch
what is Rosch’s idea of high typicality?
a category member closely resembling the category prototype
what is Rosch’s idea of low typicality?
a category member does not closely resemble a category prototype
variations within categories represent differences in _____
typicality
how did Rosch use prototypicality in an experiment?
quantified it by presenting participants with a category title and 50 members of the category for them to rate based on representation
what were the 3 conclusions Rosch came to from her prototypicality experiment?
high overlap of characteristics means there’s a high family resemblance
little overlap of characteristics means there’s low family resemblance
there is a strong relationship between family resemblance and prototypicality
who used sentence verification technique to determine how rapidly people could answer questions about an object’s category
Edward Smith
describe the sentence verification technique
presenting statements and are followed by a yes or no response to the statement being true
what did Edward Smith find using the sentence verification technique?
people responded faster for objects that are high in prototypicality
what is the typicality effect?
the ability to judge highly prototypical objects more rapidly
if someone was asked to list as many objects in a particular category, according to prototypicality, where on the list would the prototypical objects be?
in the beginning
prototypical objects can be affected more by the use of ____
priming
what is priming?
when presentation of a stimulus facilitates the response to another stimulus that usually follows close in time
how did Elanor Rosch use priming in an experiment?
used a colour name as the priming stimulus and presented pairs of colours asking if they were the same as the colour name
what were the 3 responses in Rosch’s priming experiment
- same and good representations
- same but poor representations
- different colours from different categories
what was Rosch able to conclude from her priming experiment? (2)
priming facilitates a response to a stimulus if it contains info needed
priming allows people to create images of prototypes in response to category names
describe the exemplar approach
determining whether an object is similar to other objects
what are exemplars?
actual members of a category that a person as encountered in the past
how does the exemplar approach explain the typicality effect
proposes that objects that are considered exemplars are classified faster
what is hierarchical organization?
leveled organization in which larger and more general categories are divided into small and more specific categories
what are Elanor Rosch’s 3 levels of categories?
superordinate = global
basic level
subordinate = specific
which level in Rosch’s hierarchical organization is known to be psychologically special? why?
basic level
going up a level = loss of information
going down a level = gain of information
____ can affect categorization
knowledge
how might an expert in trees identify an oak tree in comparison to a non-tree expert?
expert would identify on a more specific level therefore identify using oak tree
non-expert would identify on a basic level using tree
describe the semantic network approach
proposes that concepts are arranged in networks
Ross Quillian and Allan Collins had a network that..
consisted of nodes connected by links
describe concepts and links in Quillian and Collin’s semantic network
concepts: placed so that related concepts are connected
links: indicate how concepts are related to each other in the mind
what kind of model did Quillian and Collin’s semantic network serve as? why?
hierarchical model
levels were arranged so more specific concepts were at the bottom and more general are at the top
what is cognitive economy?
storing shared properties just once at a higher-level node
how did Quillian and Collins use reaction time to characterize their network?
to verify how a statement demonstrated travel distance in their network
if someone responded to a statement and their reaction time was long, what would Quillian and Collins conclude about it?
in order for that person to retrieve the conceptual information about that statement, it required them to travel further in their semantic network
what is spreading activation?
activity that spreads out along any link that is connected to an activated node
what is the result of spreading activation?
additional concepts become primed and can be retrieved more easily
describe the lexical decision task
participants reading words and non-words and indicating if each “word” is one or not
who used the lexical decision task ?
David Meyer and Roger Schvaneveldt
what independent variable did Meyer and Schvanveldt focus on in their Lexical Decision experiment?
association between the pairs of words
in Meyer and Schvanveldt’s experiment words that were closely related had the fastest reaction times, why?
retrieval of one word triggered a spread of activation to other nearby locations/words that are related
what was the major criticism in Quillian and Collin’s semantic network?
their theory did not explain typicality
what is connectionism?
approach to creating computer models for representing cognitive processes
who proposed the idea of connectionism?
James McClelland and David Rumelhart
why was connectionism favoured?
its inspiration of how information is represented in the brain
can explain how concepts are learned and how brain damage affects conceptual knowledge
what is parallel distributed processing?
proposes that concepts are represented by activity distributed across a network
what is a simple connectionist network?
contains circles that represent neurons and lines that represent connections that transfer information between its units
in the simple connectionist network, what are input units?
units activated by environmental stimuli and send signals to hidden units to send to output units
what is connection weight?
determines how signals sent between units increase or decrease activity of the next unit
what do connection weights correspond to in terms of neural activity?
activity at the synapse between neurons
what would a high connection weight result in?
strong tendency to excite the next unit
what would a low connection weight result in?
causing less excitation in the next unit
what would a negative weight result in?
a decrease in excitation or inhibit activation on the next unit
what 2 things does unit activation in a network depend on?
- signal that originates in the input units
2. connection weights throughout the network
what is the basic principle of connectionism?
a stimulus presented to the input units is represented by the pattern of activity across other units
do untrained networks have higher or lower connection weights?
lower
are connection weights similar or different within the network when it is untrained? what does this and their initial weight allow?
the same
property nodes to be activated
what does a properly working network require? why?
adjusted connection weights
so that activation of the concept unit and relation unit activates only certain property units
how is adjustment of connection weights achieved?
the learning process
what is the learning process?
when erroneous responses in the property units cause an error signal to be sent backward in the network
what is back propagation?
error signals being sent back to the hidden units and the representation units provide connection weight adjustment
what does back propagation result in?
correct activation of property units
what are the 2 supporting ideas that demonstrate resemblance between connectionist networks and the brain?
- operation of connectionist networks are not totally disrupted by damage
- connectionist networks can explain the generalization of learning
what is graceful degradation?
property in which disruption of performance occurs only gradually as parts of the system are damaged
what are the 4 proposals about how concepts are represented in the brain?
sensory-functional hypothesis
multiple-factor approach
semantic category approach
embodied approach
what is the sensory-functional hypothesis?
states our ability to differentiate between living things and artifacts depends on memory systems that distinguish sensory attributes and functions
what is category-specific impairment?
when people lose the ability to identify one type of object but retained the ability to identify other objects
what are the properties people typically consider when distinguishing between artifacts and living things?
living things depend on perceiving sensory features
artifacts depends on perceiving their functions
what is the multifactor approach?
the idea of distributed representation
demonstrates how members of a specific category have similar perceptual attributes but one should consider more than one when grouping
what is crowding?
refers to the fact that animals tend to share many properties
what did the idea of crowding lead to?
patients who appear to have category-specific impairment do not have it all
what new proposal/conclusion did crowding lead to?
the idea that patients who have difficulty recognizing living things have a difficulty distinguishing between items with similar features
what is the semantic category approach?
proposes there are specific neural circuits in the brain for specific categories
what did Alex Huth discover about the brain’s response to items from a particular category?
responses are distributed over a number of different cortical areas
a response to the word hammer would activate …… based on Alex Huth’s experiment
visual areas that respond to the hammer’s shape/colour
and areas that respond to how a hammer is used/its motions
what is the embodied approach?
states that our knowledge of concepts is based on reactivation of sensory and motor processes that occur during object interaction
what does the embodied approach refer to?
how perception of an object and taking action with it interact
what neurons are the link between perception and motor responses
mirror neurons
who measured participant’s brain activity using an fMRI to examine the embodied approach?
Olaf Hauk
what conditions did Olaf Hauk have his participants in?
- moving their left/right (foot/index finger) or tongue
2. reading action words (kick/pick /lick)
what did results of Olaf Hauk’s experiment show?
same areas of the cortex activated by actual movements and reading the action words
what is semantic somatotopy?
correspondence between words related to specific parts of the body and the location of the brain
based on sematic somatotopy, people who have trouble producing actions associated with objects would….
have trouble recognizing the objects associated with the action
what are the 2 kinds of features in the feature comparison model?
defining and characteristic
what are defining features?
those essential to a concept
what are characteristic features?
those common to many members of a category but are not esssential
describe the 2 stages of the feature comparison model
- comparing the degree of similarity of both kinds of features (high/low)
- only comparing defining features
what does the feature comparison model explain and what can it not explain?
can explain the typicality effect
cannot explain priming effects
