Chp 5 - Concepts & Categories Flashcards
Category
Mentally represented grouping of entities that share some kind of psychological similarity
Concept
-Our collective knowledge about particular category; grouping of things on a more or less functional commonality
- e.g. living things
- difference between “concept” and “category”
The mental representations we form of categories are called concepts
Why do we conceptualise/ categorise? (3)
- allow for adaptive behaviour
why? - savings in storage space?
- allow for inferences and predictions about new entities we encounter
things we tend not to notice about our concepts/ categories
There are only a small subset of all possible concepts/categories
- concept of edible
There is a great deal of commonality about individuals’ concepts/ categories
Semantic Memory
- organised knowledge about the world
- categories and concepts are basic components
The Classical View: The Feature Comparison Model (Smith et al., 1974)
Concepts are stored in memory according to a list of necessary features or characteristics
- e.g. features of cat
- Characteristic Features
- Defining Features
A two-stage decision process is necessary to make judgments about these concepts.
Pro: typicality effect
Based on classical view
-shows input process
Characteristic Features (The Classical View: The Feature Comparison Model)
attributes that are descriptive of the item but not essential
Defining Features (The Classical View: The Feature Comparison Model)
attributes that are necessary to the meaning of the item
Typicality Effect
Decisions are faster when an item is a typical member of the category than when it is not
- is robin a bird? vs.
- “a penguin is a bird
- robin looks more typical than a penguin in a category of a bird
The Prototype View
- Eleanor Rosch
- Some members of a category are more representative than others
- suggests that when people categorize objects, they do so based on how similar the object is to a prototypical (or ideal) example of that category
e.g. Prototype of a tree:
- pine tree is not prototypical in features
Prototypes can shift over time and can be based on culture
→ Prototypes tend to be listed as examples of categories (Mervis et al., 1976)
→ Typically show large priming effects
Network Models: Parallel Distributed Processing, Connectionism
- network organization of concepts with many interconnections
- Cognitive processes are represented in a model with activation through networks linking simple, neutron-like units
Levels of categorisation
- Superordinate level: most general (e.g. vehicle)
- Basic level: mid-point between the 2 levels (e.g. car)
- Subordinate level: most specific level (e.g. Ferrari)
The Classical View
Suggests we categorize items according to defining features that are both necessary and sufficient for category membership
Limitations of the Classical View
→ Trouble accounting for the typicality effect (i.e., people respond faster to an item when it is a typical member of the category)
→ Does not account for relationships among categories or the fact that features tend to be correlated
Limitations of The Prototype View
→ Prototypes do not necessarily show the most family resemblance
→ Prototypes differ in different contexts and seem unstable over time
The Exemplar View
Suggests we compare incoming information to an exemplar which is a composite of every item from that category we have previously encountered
Compare new item to the memory trace of the types of e.g. chairs
Semantic Networks
Suggest that information is mentally represented in terms of networks in which related concepts are “close together”
* Spreading activation
Prosopagnosia
neurological disorder characterized by the inability to recognize faces
First-order relational information
Information about the parts of an object and how those parts relate to one another
For facial recognition:
- Analysis of person’s facial features and the relationships
- Where is the nose in relation to the eyes?
Limitations:
- Not enough to recognise a face, only know it is a face, but not who (eyes are above the nose)
Second-order relational information/Thatcher Illusion
- Involves comparing first-order analysis to facial features of a “typical” and ”average” face
- Built up through experience and serves as an implicit standard
- Regardless where the car is oriented, I still know where the wheels are
- Inversion of face disrupts encoding of second-order relational information, harms facial recognition
What are the views of categorisation mentioned? (3)
Classical (Feature Comparison)
Prototype
Exemplar
