conceptual knowledge

episodic memory

autobiographical knowledge about personal past, unique to the individual

semantic memory

general knowledge about the world that all members of a culture possess

conceptual knowledge

enables us to recognize objects and events and to make inferences about their properties

concept

mental representation used for a variety of cognitive functions

categorization

process by which things are placed into groups

why categories are useful

helps us understand individual cases not previously encountered. Provide general information about an item and identify its special characteristics

Definitional approach

determine category membership based on whether the object meets the definition of the category

weaknesses of the definitional approach

not all members of everyday categories have the same defining features

prototype approach

characteristic features that describe what members of a concept are like

prototype

average of category members encountered in the past

prototype perception

the closer to the prototype an item is the easier it is to process

weaknesses of prototype approach

fluency can be mistaken for recognition, preference or truth

exemplar approach

concept is represented by multiple examples, and these are actual category members not averages

categorization process in exemplar approach

compare the new item to stored examples

strengths of exemplar approach

explains typicality effect, takes into account atypical cases, deals with variable categories

verification

indicating the truth of a test item

production

retrieving an instance from memory when given a cue

creators of the Hierarchical Network Model

Allan Collins and Ross Quillian

Hierarchical Network Model

consists of levels arranged so that more specific concepts are at the bottom and more general concepts at higher levels

assumptions of the Hierarchical Network Model

it takes time to move from one level to another and takes additional time to retrieve features stored at a level

weaknesses of Hierarchical Network Model

does not explain the typicality effect

typicality effect

faster verification of usual members of category than unusual members

Feature Comparison Model

all concepts in semantic memory are represented as sets or lists of features, no cognitive economy, same features stored with different concept

defining features

features essential to define concept

characteristic features

features that are distinctive or common but not essential

stage one of feature comparison model

retrieval of features from item and category to compare similarity, define amount of similarity (low or high), make a decision if possible depending on similarity

stage two of feature comparison model

if similarity is neither low enough or high enough to make a decision compare only defining features of items and then decide

weaknesses of feature comparison model

cannot easily explain priming effects, does not explain how verification of property statements happens

Spreading Activation Network Model

concepts organized in network, but organization is not hierarchical. Features are stores with concepts and length of links represents strength of associations. Assumes activation spreads between concepts

creates of Spreading Activation Network Model

Allan Collins, Elizabeth Loftus

connectionist approach

parallel distributed processing, knowledge is represented in the distributed activity of many units, weights determine at each connection how stonily an incoming signal will activate the next unit

process of connectionist approach

network responds to stimulus, provided with correct response or not, if not error signal activates and it is modified responding to a better match via back propagation. Repetition until error signal is zero

embodied cognition

knowledge of concepts is based on reactivation of sensory and motor processes that occur when we interact with the object

mirror neurons

neurons that fire when we do a task or observe another doing that same task

knowledge

explicit awareness of obtained and mentally available information about the world and ourselves that was obtained through experience

sentence verification technique

participants are asked to indicate whether a particular sentence is true or false

typicality effect

ability to judge the truth or falsity of sentences involving high-prototypical members of a category more rapidly than sentences involving low-prototypical members of a category.

superordinate/global level

highest more general category level

basic level

Positioned below superordinate level. Psychologically special because it is the level above which much information, and below which little is gained

subordinate/specific level

most specific category level

semantic network approach

represents knowledge as a network of interconnected nodes. Each represents a concept, and connections represents relationships between concepts

creators of semantic networks approach/ Hierarchal model

Collins and Quillian

cognitive economy

the brain organizes information in a way that minimizes cognitive effort and redundancy, storing shared properties or features of concepts at the highest possible level of hierarchal structure to efficiently use mental resource

spreading activation

activity that spreads out along any link in a semantic network that is connected to an activated node

lexical decision task

procedure in which a person is asked to decide as quickly as possible whether a particular stimulus is a work or nonword

alternative name for connectionist approach

parallel distributed processing

units

neuron like processing units in a connectionist network

input units

activated by stimulation from the environment

hidden units

located between input and output units

output units

contain the final output of the neuron

connection weight

determines the degree to which signals sent from one unit either increase or decrease the activity of the next unit

error signal

difference between the output signal generated by a particular stimulus and the output that actually represents that stimulus

back propagation

an error signal is transmitted backward through the network. Provides information needed to adjust the weights in the network to achieve the correct output signal for a stimulus

graceful degradation

related to non neural networks where performance gradually declines rather than completely falling apart when parts of a system are damaged or impaired, allowing for partial functionality to be maintained

sensory functional hypothesis

explanation of how semantic information is represented in the brain that states that the ability to differentiate living things and artifacts depends on one system that distinguishes sensory attributes and another system that distinguishes function

category-specific impairment

result of brain damage in which patients have trouble recognizing objects in a specific category

founder of SFH

warrington and Shallice 1984

multi-factor approach

describes how concepts are represented in the brain by searching for multiple factors that determine how concepts are divided up within a category

Paul Hoffman and Matthew Lambon Ralph (2013)

160 items, ask participants how much they associated one item with another in a scale from 7 to 1. Animals were more strongly associated with motion and color compared to artifacts; artifacts were more strongly associate with performed actions

crowding

animals tend to share many properties which is relevant to the representation of concepts in the brains

semantic category approach definition

there are specific neural circuits for some specific categories s

According to Bradford Mahon and Alfonso Caramazza (2011)

semantic category approach. There are a limited number of categories that are innately determined because of their importance for survival

embodied approach

knowledge of concepts is based on reactivation of sensory and motor processes that occur when we interact with an object

semantic somatotopy

correspondence between words related to specific parts of the body and the location of brain activity associated with that part of the body

semantic dementia

general loss of knowledge of all concepts. Equally deficient in identifying living things and artifacts

anterior temporal lobe

damage here has been connected with semantic deficits in dementia patients and with the savant syndrome

hub and spoke model

proposes that areas of the brain that are associated with different functions are connected to the anterior temporal lobe, which integrates information from these areas

transcraneal magnetic stimulation

noninvasive procedure that uses magnetic fields to stimulate nerve cells in the brain. Generates magnetic pulse that induces an electrical current in specific areas of the brain which can temporarily disrupt localized brain activity