Knowledge in Semantic Memory (Chapter 6) - Practice Flashcards

A set of Question-and-Answer flashcards covering key concepts from the lecture: what concepts, categories, cognitive economy, levels of abstraction, prototype vs exemplar vs knowledge-based theories, semantic networks, schemas, memory distortions, and related phenomena.

What is a concept?

A fundamental unit of symbolic knowledge; a mental representation of a category.

Why do we need concepts?

They give our world stability, help us categorize objects, and allow inference of nonperceptible attributes from perceptible ones, supporting perception, memory, language, and thinking.

What is a category?

A class of similar things that share an essential core or a similarity in properties, treated as equivalent.

What are natural categories (natural-kind concepts)?

Groupings that occur naturally in the world (e.g., birds, trees, dogs); relatively stable.

What are artefact categories?

Groupings invented by humans (e.g., kitchen appliances, vehicles); relatively stable.

What are nominal concepts?

Precise definitions.

What are ad-hoc categories?

Formed on the run; not enduring (e.g., things to sell at a garage sale or to carry out of the house in a fire).

What is cognitive economy?

Hierarchical organization reduces the amount of information we must learn; higher (more general) levels are less informative.

What is the basic level of categorization?

The mid-level (basic) category that balances informativeness and economy; e.g., dog versus animal or Airedale Terrier.

What is the Prototype approach?

Categories are represented by an abstract prototype—an average/central tendency of category members containing salient features.

What is the Exemplar approach?

Categories are represented by stored examples; categorization depends on similarity to known exemplars.

What is the Semantic (knowledge-based) approach?

Focus on semantic relations and contextual features; categorization depends on knowledge and context.

What are defining features (intension vs extension)?

Intension: defining attributes of membership; Extension: the set of members. Membership relies on necessary and sufficient features.

What is the Classical (defining features) approach to categorization?

Membership is clear-cut; all members are equally good representatives; subordinate concepts inherit attributes from superordinate concepts.

What is a problem with the Common Features approach?

Many concepts have fuzzy boundaries and gradual transitions; definitions may not reflect how we actually think (e.g., pumpkin as fruit vs. vegetable).

What is a limitation of the Prototype approach?

Prototypes may not reflect the features of most members; familiarity or expertise can override prototype; abstract concepts can be problematic.

What is family resemblance?

Members share different features; few, if any, features are shared by all; category membership is a matter of similarity to different members.

What are the special properties of the basic level (Rosch, 1976)?

Objects are spontaneously named at this level, learned early, show many attributes and maximal within-category similarity, and have faster recognition.

What did Tanaka & Taylor (1991) find about expertise and basic level use?

Experts tend to use subordinate levels within their domain; novices rely on the basic level; familiarity influences level of categorization.

What is a semantic network (Collins & Loftus, 1975)?

A network with shorter links for closely related concepts and longer links for distant ones; no fixed hierarchy; based on experience.

What is spreading activation?

Activation spreads along links from an activated node to related nodes, priming them for faster retrieval.

What is a schema?

A set of related propositions forming a packet of typical knowledge about the world, events, or people; guides recall and expectations.

What is the Event-indexing model?

Propositions are linked by events across time, space, entity, causation, and motivation to form a memory of a situation.

What is the War of the Ghosts ( Bartlett )?

A memory study showing recall distortion and reconstruction across retellings, illustrating schema-driven memory.

What is consistency (or the consistency) bias in memory?

The tendency to exaggerate the consistency between past memories and current beliefs or feelings.

What did Brewer & Treyans (1981) show about schema-driven memory?

People recalled more schema-consistent objects present and falsely recalled schema-consistent objects not present.

What is semantic dementia?

Widespread loss of knowledge about meanings of concepts/words, with impaired categorization and drawing, unlike primarily episodic memory impairment in Alzheimer’s.