Cognitive Processes Chapter 9

What are the building blocks of all knowledge?

Basic concepts like "chair" and "dog".

Why is categorization important?

It enables you to apply your general knowledge to new cases.

— It also enables you to draw broad conclusions from specific experiences.

What is a problem with the definitional approach?

It is always possible to find exceptions to our definitions.

What is family resemblance?

Members of a category share a family resemblance.

— No defining features

— Characteristic features across family members.

Why do family members resemble one another?

Each member of the family shares at least some features with this ideal, and therefore has some features in common with other family members. This feature overlap is why there is resemblance.

How do ordinary categories and family resemblance interconnect?

Wittgenstein proposed that ordinary categories like "dog" work in the same way. They may be no features that can be shared by all dogs, even so we can identify characteristics features that perhaps most dogs have. These are the features that enable you to recognize that is a dog.

What is a prototype?

The category example that possesses all the characteristic features, the ideal

True or False: Resemblance is a matter of degree

True

What is typicality?

The degree to which a particular case (an object, situation, or event) is typical for its kind.

What is graded membership?

The idea that some members of a category are "better" members and therefore are more firmly in the category than other members.

True or False: Objects close to the prototype (meaning they have a high typicality) are better members of the category than objects further from the prototype.

True

How do definitions set boundaries?

If "inside" boundaries, a test case has attributes (meaning it belongs)

If "outside" boundaries, a test case does not have features (doesn't fit definition.)

What is a sentence verification task?

A procedure in which participants are briefly presented with simple sentences and asked to make quick judgments about them. (True or False)

Example of sentence verification task

True or false? Pigeons are Birds.

True or false? Penguins are birds.

What is concluded from sentence verification tasks?

Judgements about items that are more distant from the prototype take more time to make.

Faster response when there is a close similarity between test case and prototype.

What is a production task?

A procedure used in studying concepts, in which the participant is asked to name as any examples (e.g., as many fruits) as possible.

How do production tasks work cognitively?

First locating their bird or dog prototype in memory and then asking themselves what resembles this prototype. They start with the center of the category (the prototype) and work their way outward from there.

Things most similar are mentioned first, things further away from prototype mentioned later on.

What is basic-level categorization?

A level of categorization hypothesized as the "natural" and most informative level, neither too specific nor too general. People tend to use basic-level terms (such as "chair," rather than the more general "furniture" or the more specific "armchair") in their ordinary conversation and in their reasoning.

What is a rating task?

A task in which research participants must evaluate some item or category with reference to some dimension, usually expressing their response in terms of some number. For example, they might be asked to evaluate birds for how typical they are within the category "birds," using a "1" response to indicate "very typical" and a "7" response to indicate "very atypical.

How does typicality influence attractiveness?

People seem to find the more-typical category member to be more attractive.

What is exemplar-based reasoning?

Reasoning that draws on knowledge about specific category members, or exemplars, rather than drawing on more general information about the overall category

True or False: Conceptual knowledge only includes prototypes.

False

It is useful that it includes both prototypes and exemplar, as they both have their advantages.

What is the difference between prototype and exemplar?

Prototypes provide an economical (quicker) summary of category.

Exemplars provide information about category variability, but less economical. It is easier to adjust categories based on exemplars than prototypes (i.e., gift for a 4-year-old and gift for a 4-year-old that broke her wrist.)

True or False: Category judgements can be independent of typicality

True

What is an example of atypical features that don't necessarily exclude category members?

A lemon that is painted with red and white stripes, injected with sugar to make it sweet, and then run over with a truck is still a lemon.

What is an example of objects that have typical features but are rejected as category members?

A perfect counterfeit bill, it is not an actual bill.

How do we declare that objects are similar?

Focusing on the attributes that you believe to be essential for each category

How do we determine what attributes are essential?

It depends on your own beliefs about the category (cost, weight, physical characteristics)

How do we judge resemblance?

Unrelated objects can share thousands of properties, but decisions about which features are important to resemblance still depend on one's beliefs about the concept.

Summary of Resemblance

You focus on attributes that you believe are essential for each category, even if the stimulus does not resemble the prototype at all. Your judgments about what’s essential, however, depend, on your beliefs about that category.

What is the broader role of conceptual knowledge?

1. Typicality influences category judgments.

2. Typicality effects reveal the substantial role of prototypes and exemplars.

3. When using a prototype or exemplar, you rely on a judgment of resemblance.

4. That judgment of resemblance depends on other knowledge.

•Which attributes to pay attention to? Which attributes to ignore?

•The abused lemon resembles other lemons in the ways that matter.

•The counterfeit bill doesn’t resemble real money in the ways that matter.

How does category knowledge guide our thinking about new cases?

Theories we hold enable us to:

•think about causes

•think about new possibilities for categories

•learn new concepts

Can a plane be made of wood? Ceramic? Whipped cream?

•At a party, someone jumps into the pool fully clothed... why?

In what ways are natural kinds and artifacts reasoned about differently?

People tend to assume more stability and more homogeneity with reasoning about natural kinds. These principles don't relate to artifacts as though we believe they can be manipulated.

What is an example between the reasoning difference of natural kinds and artifacts?

A skunk cannot be turned into a raccoon, but it is possible to turn a toaster into a coffeepot.

How can concepts be characterized?

•Features

•Goal-derived categories (e.g., diet food, exercise equipment)

•Relational categories (e.g., hunting)

•Event categories (e.g., dates, shopping trips)

What is the relationship between concepts and the brain?

fMRI scans show that different brain sites are activated when people are thinking about living things as opposed to when thinking about nonliving things. Different sites are also activated when thinking about manufactured objects and natural objects.

What is anomia?

Losing the ability to name certain objects or answer simple questions about these objects.

Some patients lose the ability to name living things but not non-living things, and others show the reverse pattern. Brain damage can be more specific as a patient might not be able to answer questions about fruits and veggies but can answer on other objects living or nonliving.

When recognizing living things, what properties are used?

Perceptual properties, especially visual properties that enable us to identify horses or trees or other animate objects

When recognizing non-living things, what properties are used?

Functional properties

What is conceptual knowledge intertwined with?

Knowledge about what particular objects look like (or sound/feel like) and also with knowledge about how one might interact with the object.

What is grounded (embodied) cognition?

Body's sensory and action systems play an essential role in all our cognitive processes; it's inevitable that our concepts will include representations of perceptual properties and motor sequences associated with each concept.

Damage to the temporal lobe is associated with what kind of anomia?

Difficulty naming persons, but were easily able to name animals and tools.

Damage to the inferotemporal region is associated with what kind of anomia?

Difficulty in naming persons and animals, but did somewhat better in naming tools.

Damage to the lateral occipital lobe is associated with what kind of anomia?

Difficulty naming tools, but did reasonably well naming animals and persons.

What is the hub and spoke model?

A proposal for how concepts might be represented in the brain, with tissue in the anterior temporal lobes serving as the "hub"—a brain location that connects and integrates information from many other brain areas. The "spokes" represent more specific elements of the concept —with (for example) visual information relevant to the concept stored in visual areas; relevant action information stored in motor areas; and so on.

If the damage involves the ATL (Anterior temporal lobe) what occurs?

The person seems to lose general knowledge associated with various concepts.

If the damage involves the "spokes" what occurs?

The person will show more specific symptoms, such as an inability to make certain types of judgement about the concept.

What do associative links do?

Not only tie together the various bits of knowledge but also help represent the knowledge.

Example: George Washington was an American president. This simple idea can be represented as an associative link between a node representing Washington and a node representing President.

True or False: You'll need less time to retrieve knowledge involving closely related ideas, and more time to retrieve knowledge about more distant ideas

True

What is an example of "travelling through the network"?

Seeking a connection between nodes. When the participant finds the connection from, say, the robin node to the birds' node, this confirms that there's an associative path linking these nodes, which tells the participant that the sentence about these two concepts is true. This travel should require little time if the two nodes are directly linked by an association, as robin and birds probably are. In this case, we'd expect participants to answer "true" rather quickly.

What did Collins and Quillian propose?

The memory system avoids redundant storage of connections between CATS and HAVE HEARTS, and between DOGS and HAVE HEARTS, and so on for all the other animals. Instead, HAVE HEARTS is stored as a property of all animals. To confirm that cats have hearts, therefore, you must traverse two links: from CATS to ANIMALS, and from ANIMALS to HAVE HEARTS.

What did Collins and Quillian argue?

There's no point in storing in memory the fact that cats have hearts and the fact that dogs have hearts, etc... Instead, they proposed, it would be more efficient just to store the fact that these various creatures are animals, and then the separate fact that animals have hearts. As a result, the property "has a heart" would be associated with the ANIMALS node rather than the nodes for each individual animal, and the same is true for all the other properties of animals, as shown in the figure.

What is an example of the relationship between time and travelling through nodes?

In a sentence verification task, participants' responses were fastest when the test required them to traverse zero links in memory ("A canary is a canary"). They were slower when the necessary ideas were separated by one link, and slower still if two links separated the ideas. Responses were also slower if participants had to take the additional step of traversing the link from a category label ("bird") to the node representing a property of the category (CAN FLY).

What are the problems behind the Collins and Quillian study?

Problem #1:

Sentence verifications are faster if the sentence is about a more prototypical stimulus.

•"A canary is a bird." versus "An ostrich is a bird."

Problem #2:

The principle of "nonredundancy" does not always hold.

•"Birds have feathers." versus "Peacocks have feathers."

•Participants respond quickly to the peacocks question, because peacocks have prominent tail feathers

What is a propositional network?

A diagram in which the terms of a proposition and the relations between them are represented as nodes linked to form a network. Defined as the smallest units of knowledge that can be either true or false.

What are distributed representations?

Ideas represented by means of a specific pattern of activation across the network

Why do distributed representations require distributed processing?

A network using distributed representations must use processes that are similarly distributed, so that one widespread activation pattern can evoke a different (but equally widespread) pattern. In addition, the steps bringing this about must all occur simultaneously—in parallel—with each other, so that one entire representation can smoothly trigger the next.

What is parallel distributed processing?

A system of handling information in which many steps happen at once (i.e., in parallel) and in which various aspects of the problem or task are represented only in a distributed way

According to Wittgenstein,

a)we have no real general concept for each category that we know, but instead learn each category member individually.

b)we assess category membership probabilistically, based on family resemblance.

c)we can find rigid features that define a category but only after intensive study.

d)we first encounter the prototypical member of a category and then compare all other potential members to it.

B

Wittgenstein developed the idea of family resemblance within categories rather than all-or-none categories based on definitions.

Which of the following is true?

a)People only use prototypes when there are no clear definitions to fall back on.

b)Just because people use prototypes does not mean that this is the only information available to them.

c)People use exemplars rather than prototypes whenever possible.

d)Clearly defined category boundaries are necessary for deciding category membership.

B

Generally, prototypes may be used in situations where exemplars are available as well.

In a production task, the __________ category members that a person mentions are the category members that produce the slowest reaction times in a sentence verification task.

a)first

b)last

c)loudest

d)slowest

B

The first members produced are usually the prototypes, and hence those most tightly linked to a category. The last members will be more loosely linked, and hence will be last. Generally, the more prototypical members are also those that are the fastest to be verified as belonging to the category.

The idea that we categorize objects based on their similarity to specifically stored instances is known as __________ theory.

a)geometric

b)prototype

c)feature

exemplar

D

Exemplars are instances of an item. The idea is that we store these examples in our memory.

Which of the following is NOT true of category knowledge?

a)Category judgments are influenced by typicality.

b)Judgments of resemblance will override our beliefs about categories.

c)We are more likely to generalize about a category from typical cases than from atypical cases.

d)Our beliefs and prior knowledge can influence how quickly we learn new concepts.

B

When making a judgment about category membership, we rely partly on judgments of resemblance (e.g., how similar is this item to other exemplars or prototypes that I've seen?). That judgment of resemblance, though, depends on other knowledge, and beliefs about essential properties can be more important than resemblance alone in deciding category membership.