CCC- Knowledge

Question 1

What is episodic memory?

Answer 1

Reference is to oneself
Organised temporally (overtime)
Events recalled “consciously”
Susceptible to forgetting
Context dependent

Question 2

What is semantic memory?

Answer 2

Reference to knowledge only
Not organised temporally
Events are “known”
Relatively permanent
Context independent

Question 3

Evidence and challenges for episodic - semantic distinction?

Answer 3

Interdependence of the systems makes distinction unclear
Does memory of an important autobiographical event remain episodic or become semantic?
Some evidence from different pathologies e.g. Semantic Dementia

Question 4

Episodic- semantic distinction
What evidence is there?

Answer 4

Semantic Dementia (SD)

Question 5

What is semantic demetia?

What are the symptoms?

Answer 5

Non-alzheimer type degenerative pathology of the polar and inferolateral temporal cortex (relative sparing of hippocampus in early stages).

Progressive, selective deterioration in semantic memory

Reasonably preserved episodic memory ( there are different structures involved in the preservation of semantic & episodic memories)

Question 6

Study

Graham et al (2000): A comparison of SD with Alzheimer’s disease (AD)

What did he find?

Answer 6

Poor object naming in semantic dementia- but not Alzheimers disease.

Question 7

What models are used for the structure of semantic memory?

Answer 7

Feature comparison models
Prototype models
Exemplar models
Network models

Question 8

Feature comparison models (Smith et al. 1974)

What are they?

Answer 8

Concepts (mental representations of objects / categories) are stored as lists of defining or characteristic features.

Sentence verification task:
Reaction time taken to verify a sentence

Is a carrot a vegetable?

2) Is an artichoke a vegetable?

1 is quicker as carrot has more characteristic features. Called the “Typicality Effect”

Question 9

What are limitations of the Feature Comparison models?

Answer 9

Few concepts can be reduced to list of defining characteristics
(e.g. a “Game”)
Features are not independent (objects with leaves are less
likely to have legs than objects that have fur).

Question 10

What do the Prototype models (Rosch, 1973) do?

Answer 10

Category membership is not clear cut – prototype models define the “centre” (average) of a category, rather than its boundaries.

Prototypicality effect:
Defining characteristics of “batchelor” – male / unmarried

Single 32 Year old man
9 Year old boy
64 Year old Catholic priest

Faster to confirm 1 than either 2 or 3 (Lakoff, 1987). Called the “Prototypicality effect”

Categories have a graded structure: some members are more representative (prototypical) than others.

Question 11

Prototype models, Rosch 1973

What are the key claims of prototype models?

Answer 11

Prototypes differ from non-prototypes

The examples of a category most often generated are also those rated as most prototypical (Mervis et al 1976).

Semantic priming: We are faster to decide if “Apple” is a word if it is preceded by the unconsciously presented word “Fruit”. This priming effect is greater for prototypes

Prototypes share most features with other category members.

2) Objects are categorised at 3 different levels: superordinate, basic, subordinate.

Question 12

What is semantic priming?

Answer 12

Refers to the observation that a response to a target (e.g., dog) is faster when it is preceded by a semantically related prime (e.g., cat) compared to an unrelated prime (e.g., car).

Question 13

Structure of semantic memory

Prototype models

Rosch 1973- What does the model include?

Answer 13

Superordinate: Furniture, animal, tool

Basic: chair, dog, hammer

Subordinate: Armchair, boxer, claw hammer

Question 14

How do basic level categories have a special status?

Answer 14

We use them to name objects
They show the largest semantic priming effects
They distort memory

Question 15

Prototype models summary

Advantages:

Disadvantages:

Answer 15

Advantages:

Can explain a lot of empirical findings
Allows “loose” concepts to be created- (don’t have to define features of everything.)

Disadvantages:
Prototypes can change with context (e.g Novick, 2003).
Prototypes “lose” information.
Experts have different prototypes…have different knowledge

Question 16

What is an alternative view to the prototype model?

Answer 16

That we use exemplars, not prototypes (e.g. Nosofsky, 1991).

The two models are related as they both involve comparisons between external reality and an internally generated “standard”

Question 17

Structure of semantic memory

Exemplar Models (e.g. Nosofsky, 1991) ?

Answer 17

Specific exemplars rather than ‘averaged’ prototypes drive the typicality effects – easy to find specific memories of common objects (e.g. apple) compared to uncommon ones (e.g. fig).

Question 18

What are the benefits & limitations of exempler models?

Answer 18

Benefits:
Do not require abstraction (averaging)
Preserve information about variability
- Is a 19” object more likely to be a Pizza or a Ruler?

Limitations:
Applies to complex more than simple categories e.g even no.s.
Infers that we store every single example of a category
Both Exemplar and Prototype models can coexist

Question 19

Structure of semantic memory

Network Models - Hierarchical Nets (Collins & Quillian, 1969)

What does this model show?

Answer 19

Emphasise the relationship between concepts.
Relates to feature comparison models.
Closer in diagram- the more semantically related they are.
this is apparent when doing priming studies.

Key concepts:
Concepts represented by Nodes
Nodes connected by Links
Semantic Relatedness

People faster to verify:
Canaries are yellow than
Canaries have feathers

Question 20

Structure of semantic memory

Network models- (semantic nets)(Collins & Loftus,1975)

What are the key concepts?

Answer 20

Key Concepts:
Semantic Distance (represented by number of links/ length of lines)
Spreading activation
Link strength or weight
(depicted by length here)

Evidence:
Semantic priming greater for “closer” items (McNamara, 1992)
False memory effects: DRM paradigm.

Question 21

Network models- semantic nets

How does spreading activation work?

Answer 21

Operates on interconnected nodes within semantic memory.

When one node is externally activated, activation spreads to related concepts, thus raising their baseline.
Priming occurs when a pre-activated concept is presented as a target

Question 22

Network models- semantic nets

What are false memory effects?

Answer 22

False memory effects- if activate word e.g. red- you will slightly activate related words & concepts-

If you have to remember the words that are slightly activated- even though they weren’t presented- may result in a false memory of them.

Question 23

Network Models – ACT-R (Anderson, 1983, 2000)

What does the model stand for?
What is the model & what will be focus on?

Answer 23

(Adaptive Control of Thought – Rational)

A theory of all cognition
Attention / Visual Cognition / Memory / Action
Declarative Memory is one small part

Question 24

Network Models – ACT-R (Anderson, 1983, 2000)

What is declarative memory?

What is declarative memory made up of?

Answer 24

A type of long-term memory that involves conscious recollection of particular facts and events.

Declarative memory consists of propositions – the smallest unit of information that can be declared true or false.(use this to make inferences if the propositions are correct)

e.g. proposition- all swans are white.
Wacky is a swan
It would then be correct to say wacky is white.

Question 25

Network Models – ACT-R (Anderson, 1983, 2000)

What happens when the links are activated more?

Answer 25

The stronger (faster) they become.

Question 26

What is the fan effect?

Answer 26

Time to make True / False decisions increases with the number of items of information associated with the location and person.

If strengthen the basic concept- easier to make connections.

E.g. if football fan & can hear facts about the team- the fact sticks.
Can make links- the stronger the concept is- e.g. because you know lots about the football team.

Question 27

Network Models – Parallel Distributed Processing
(McClelland & Rumelhart, 1986)

What are the key features?

Answer 27

“Neuron like” nodes connected by links.

A concept is represented by a pattern of activity distributed across many nodes

Links have different “weights”

Information processing proceeds in parallel – many patterns of spreading activation may occur at the same time.

PDP models allow for spontaneous generalisation and graceful degradation.

Question 28

Network Models – Parallel Distributed Processing
(McClelland & Rumelhart, 1986)

What is an example of spontaneous generalization?

Answer 28

If get bitten by dog- not just fear dogs but will fear other things that are furry like dogs.

Question 29

What does semantic memory also store- other than concepts?

Answer 29

Schemas
Scripts

Question 30

What are schemas?

Answer 30

Generic information about situations / general rules that are typically accurate- mental framework for knowledge about your life.

Question 31

What is a script?

Answer 31

Structured, ordered sequence of events – can be a prototype – an abstraction. (basically schema but has order or process of event- e.g. visiting a restaurant- what you do when go to restaurant/ the process)

Question 32

Schemas can distort memory (Brewer & Treyens, 1981)

What did participants have to do?

What did they find?

Answer 32

Participants spend 35 seconds waiting in office.
Most participants remembered desk / chair / shelves / typewriter[!] etc
Books and filing cabinets often recalled
Picnic hamper and wine bottle rarely recalled

Less likely to remember things outside of the scheme.
If something is consistent with the schema- likely to then remember it.