Category
A set of objects can be treated as equivalent in some way (e.g., cars)
Concepts
The mental representations we form of categories (e.g., how to use a car)
Well defined categories define of two parts, which two?
- The necessary characteristics for membership (e.g. ,a dog has four legs, is an animal, and barks)
- These characteristics together must be sufficient for membership (e.g., an animal with four legs that barks is a dog)
What are the three types of categories?
- Natural categories: occur naturally in the world
- Artifact categories: contain objects designed or invented by humans to perform certain functions
3.Ad hoc categories: formed only in the service of a particular purpose
Fuzzy boundaries
members and non-members form a continuum with no clear break in membership
Typicality
even among items that clearly fall into a category, some seem to fit better than others
The most typical item is called the ____
The most typical item is called the prototype
Family resemblance theory
Typical items have features that are common in the category and do not have features that are common in other categories
Basic level of categorization shows that ____
Basic level of categorization shows that people prefer to use categories that are not too wide (e.g., animal) and not too small (e.g., brown bear) to name an object
The Similarity-based approaches to concepts state ___
The Similarity-based approaches to concepts state that categorization is a matter of judging the similarity between the item and a standard in long-term memory
What are the three Similarity-based approaches?
1.Classical view
2.Prototype approach
3.Exemplar approach
Classical view
Items are classified into a category if they have certain features or characteristics that are necessary and sufficient
Prototype approach
Items are classified into a category if it has high family resemblance
Exemplar approach
We represent categories in terms of examples
The Knowledge approach states that ____
We learn new concepts by connecting them to knowledge we already have about the real world
Psychological essentialism
People tend to believe that some categories have an underlying essence that causes the features of that category
Semantic networks
Knowledge is stores as associative networks where concepts are represented by nearby nodes that correspond to related concepts or features of a given concept
Semantic priming
When certain concept is presented, the corresponding node is activated and spreads to other concepts in the network
Category and feature verification task
- Category verification task: participants confirm or deny statements whether something is in a category
- Feature verification task: participants confirm or deny statements about characteristics of categories
With semantic priming, the power of activation decreases ____
activation decreases with time, distance, and the number
Semantic dementia
A progressive deterioration of the conceptual knowledge that supports semantic performance
What were the results of the Semantic Dementia experiment?
- Patients with semantic dementia produces less correct information in their drawings than the control subjects
- The impairments are due to selective damage to central conceptual knowledge
- There was a significant impact of item’s familiarity on the success of the drawing
