Three types of concepts
Brunere et al.
1) Simple Concepts: These are defined by a single, straightforward attribute.
2) Conjunctive Concepts: These concepts require multiple attributes to be met simultaneously.
3) Disjunctive Concepts: These concepts require that at least one attribute from a set of attributes is present.
Strategies for remembering disjunctive concepts
- Successive Scanning: Participants kept a single hypothesis in mind (e.g., “square and blue”) and focused on cases that directly tested this hypothesis
- Conservative Focusing: Participants started with a positive instance of the concept and made incremental changes, testing the validity of each change with new positive instances while ignoring negative instances.
- Focus Gambling: Similar to conservative focusing but allowing for more feature changes. The choice of strategy depended on time constraints and the limits of memory capacity
Classical theory of concepts
According to this theory, concepts are defined by clear-cut definitions, where every defining feature is individually
necessary (all members of this category have each of the features) and jointly sufficient (when all these features are
present in an instance, it must be a member of the category)
Prototype theory
- Concepts are organized around typical examples of categories, represented by characteristic features
- These features describe prototypes, but are not necessary features
- Weights may be assigned to features based on their salience for categorization
- During classification, an object’s similarity to the prototype is assessed and if it meets a threshold, the object is characterized as a member
Exemplar-based theory
- Proposes that our long term memory is filled with numerous memory representation (exemplars) for members of each category.
- When we need to categorize a new object and need to categorize it, all the exemplars are compared to the new object and look for a match (doesn’t have to be exact)
Explanation-based theory
- Proposes that people categorize objects based on common-sense explanations linked zo intuitive theories about the world
- These explanations specify which attributes should be used for categorization (some attributes are central or diagnostic and others superficial or surface)
Systems of category learning
Smith et al.
- Working memory (WM): Allows for the conscious analysis and short-term retention of category-relevant information
- Explicit long-term memory (LTM): It plays a role in both the learning of new categories (by storing newly acquired information) and in the recognition of familiar categories (by recalling previously learned information)
- Implicit memory: Involved in the more automatic aspects of category learning. This includes developing an intuitive sense of a category, often through repeated exposure and practice
