Categories and concepts- introduction

Categories and concepts- introduction
CS182/Ling109/CogSci110 Spring 2008

Lecture Outline Categories Aspects of a Neural Theory of concepts
Basic Level Prototype Effects Neural Evidence for Category Structure Aspects of a Neural Theory of concepts Image Schemas Description and types Behavioral Experiment on Image Schemas Event Structure and Motor Schemas

Concepts are not categorical

Mother The birth model The genetic model The nurturance model
The person who gives birth is the mother The genetic model The female who contributes the genetic material is the mother The nurturance model The female adult who nurtures and raises a child is the mother of the child The marital model The wife of the father is the mother The genealogical model The closest female ancestor is the mother (WFDT Ch.4, p.74, p.83)

Radial Structure of Mother
Genetic mother Stepmother Unwed mother Adoptive mother Central Case Surrogate mother Birth mother Biological mother Natural mother Foster mother The radial structure of this category is defined with respect to the different models

Marriage What is a marriage?
What are the frames (or models) that go into defining a marriage? What are prototypes of marriage? What metaphors do we use to talk about marriages? Why is this a contested concept right now?

Concepts and radial categories
Concepts can get to be the "prototype" of their category in various ways. Central subcategory (others relate to this) Amble and swagger relate to WALK Shove relates to PUSH Essential (meets a folk definition: birds have feathers, beaks, lay eggs) Move involves change of location. Typical case (most are like this: "sparrow") Going to a conference involves air travel. Ideal/anti-ideal case (positive social standard: "parent"); anti-ideal case (negative social standard: "terrorist") Stereotype (set of attributes assumed in a culture: "Arab") Salient exemplar (individual chosen as example)

Category Structure Classical Category: Radial Category:
necessary and sufficient conditions Radial Category: a central member branching out to less-central and non-central cases degrees of membership, with extendable boundary Family Resemblance: every family member looks like some other family member(s) there is no one property common across all members (e.g. polysemy) Prototype-Based Category Essentially-Contested Category (Gallie, 1956) (e.g. democracy) Ad-hoc Category (e.g. things you can fit inside a shopping bag) My original example for an ad-hoc category was “things you’ll bring to a picnic”, but a keen student pointed out that it is in fact a frame-based category (the picnic frame).

Prototype Cognitive reference point Social stereotypes
standards of comparison Social stereotypes snap judgments defines cultural expectations challengeable Typical case prototypes default expectation often used unconsciously in reasoning Ideal case / Nightmare case e.g. ideal vacation can be abstract may be neither typical nor stereotypical Paragons / Anti-paragons an individual member that exhibits the ideal Salient examples e.g. 9/11 – terrorism act Generators central member + rules e.g. natural number = single-digit numbers + arithmetic

Neural Evidence for category structure
Are there specific regions in the brain to recognize/reason with specific categories?

Category Naming and Deficits
People with brain injury have selective deficits in their knowledge of categories. Some patients are unable to identify or name man made objects and others may not be able to identify or name natural kinds (like animals)

A PET Study on categories (Nature 1996)

Study 16 adults (8M, 8F) participated in a PET (positron emission tomography) study. Involves injecting subject with a positron emitting radioactive substance (dye) Regions with more metabolic activity will absorb more of the substance and thus emit more positrons Positron-electron collisions yield gamma rays, which are detected Increased rCBF (regional changes in cerebral blood flow) was measured When subjects viewed line drawings of animals and tools.

The experiment Subjects looked at pictures of animals and tools and named them silently. They also looked at noise patterns (baseline 1) And novel nonsense objects (baseline 2) Each stimulus was presented for 180ms followed by a fixation cross of 1820 ms. Drawings were controlled for name frequency and category typicality

medial lateral

Left middle temporal gyrus
ACC Premotor

Calcarine Sulcus

Conclusions Both animal and tool naming activate the ventral temporal lobe region. Tools differentially activate the ACC, pre-motor and left middle temporal region (known to be related to processing action words). Naming animals differentially activated left medial occipital lobe (early visual processing) The object categories appear to be in a distributed circuit that involves activating different salient aspects of the category.

What are schemas? Regularities in our perceptual, motor and cognitive systems Structure our experiences and interactions with the world. May be grounded in a specific cognitive system, but are not situation-specific in their application (can apply to many domains of experience) So where do image schemas fit into this? --The idea is that there are regularities in our perceptual, motor and cognitive systems that structure our experiences and interactions in the world. -- For spatial relations, these structural regularities are presumably the basis for semantic primitives. Image schemas describe these primitives, but in addition, primitive schemas can be combined to form more complex image schemas. Image schemas are schematic in at least two ways – though they may be grounded in a specific cognitive or perceptual system, they are not situation-specific in their application (i.e. can apply to many domains of experience, unlike many frames). -- The entities that they apply to are only schematically specified, e.g. they do not apply only to specific shapes or types of objects.

Basis of Image schemas Perceptual systems Motor routines
Social Cognition Image Schema properties depend on Neural circuits Interactions with the world What sort of regularities are we talking about, and what is their basis? Perceptual system: -- Visual system – edge-detecting and orientation-sensitive cells CHECK -- Equilibrium – know orientation of head and body relative to gravity -- Proprioceptic – we are sensitive to the changing tensions of muscles and tendons -- We can sense contact and pressure on our skin Motor routines, with their own structure often referred to as X-schemas [will hear more on this later in course] Neural basis, e.g. generalization of input -- different pathways in the brain – the so-called “what” and “where” pathways in the brain These may use different types of visual information (and for different purposes, e.g. object identification vs. location) Interactions with the world -- affordances of objects, functional purpose of interaction (e.g motor control) --Information from the primary visual cortex (located at the back of the head) is transmitted along two pathways -- the ventral stream to the temporal cortex (the so-called "what" system) and the dorsal stream to the parietal cortex (the "where" system).

Image schemas Trajector / Landmark (asymmetric)
LM TR Trajector / Landmark (asymmetric) The bike is near the house ? The house is near the bike Boundary / Bounded Region a bounded region has a closed boundary Topological Relations Separation, Contact, Overlap, Inclusion, Surround Orientation Vertical (up/down), Horizontal (left/right, front/back) Absolute (E, S, W, N) bounded region boundary

Perceptual and motor systems
Similarity: Perceptual and motor systems Basic functional interactions with the world Environment Variation: Cross-linguistic variation in how schemas are used. Most of these bases are shared by all humans -- humans all share: perceptual and motor systems Basic functional interactions with the world such as eating, walking around, manipulating objects Similarities in environment such as gravity, the presence of a ground surface, some sort of plants, water. Though there are of course important geographical variations, such as living in a mountainous area where many ground surfaces are sloping vs. living in a flat environment So there may be a basic, universally available inventory of primitive schemas (e.g. basic perceptual distinctions that we can make, such as up and down, light and dark, and schemas for motion and orientation of our body) BUT, as we have seen, these schemas may be used in different combinations in different languages.

Cross-linguistic Variations
Let’s look at some a specific example of cross-linguistic variation. Many languages use adpositions (e.g. prepositions) to describe the relations between two objects. But the range of scenes which a given adposition can describe varies across languages. Consider, for example, the word used to describe the center picture, the one with the cup on the table

English In English the same word – on -- can describe several relations – the ones that have the white line around them. [Describe each] All of these involve contact. They are not, however necessarily restricted to vertical relations (e.g. ring on finger, apple on arrow)

Japanese Japanese – used only for vertical relations, but don’t distinguish between presence or absence of contact – not apple on stick or stamp on letter, but will be used for what would be described in English as light over table.

Tamil Dutch – only used for surface-to-surface relations, e.g. cup on table and stamp on letter. So the relations expressed by English word on are not universal. However, concepts like contact, horizontal support, and vertical relation may well be. So there may be semantic primitives, but they are not combined the same way in all cultures and languages. And some distinctions are (obligatorily) marked in a particular language, whereas others are not Terry Regier’s work used many of these primitives…and built a system that could combine them in different ways, in order to learn the spatial relation terms of different languages.

English ON AROUND OVER IN Bowerman & Pederson

Dutch AAN OM BOVEN IN OP Bowerman & Pederson

Chinese SHANG ZHOU LI Bowerman & Pederson

Spatial schemas TR/LM relation Boundaries, bounded region
Topological relations Orientational Axes Proximal/Distal We’ll start by looking at a few of the more basic schemas and see how they’re structured. I’ll talk about -- TR/LM – this is a very basic locational schema --boundaries and bounded regions --topological relations between bounded regions or objects, things like contact and inclusion --orientational axes –talk about vertical and horizontal distinctions, and different frames of reference that are used to determine them -- proximal distal schema, a schema about relative distances --

Representing image schemas
schema name schema Source-Path-Goal roles source path goal trajector schema Container roles interior exterior portal boundary role name Boundary Interior Trajector Portal Source Goal Path Exterior These are abstractions over sensorimotor experiences.

Schema Formalism SCHEMA <name> SUBCASE OF <schema>
EVOKES <schema> AS <local name> ROLES < self role name>: <role restriction> < self role name> <-> <role name> CONSTRAINTS <role name> <- <value> <role name> <-> <role name> <setting name> :: <role name> <-> <role name> <setting name> :: <predicate> | <predicate>

Trajector/Landmark Schema
Roles: Trajector (TR) – object being located Landmark (LM) – reference object TR and LM may share a location (at) Spatial relations are typically used to describe where an object is. One of the primary ways to do this is to locate one object with respect to some other reference object. The TR/LM schema is a representation of this very basic relation. It has two roles: --The TR – the object being located -- the LM – the object whose location is already known, I.e. the reference object These terms are pretty much equivalent to Figure (TR) and Ground (LM), as used by Talmy and others. The simplest instantiation is when the TR shares the same (general, static) location as the LM (roughly equivalent to the English at). However, the TR doesn’t necessarily have the same location as the LM. Rather, more specific spatial relation schemas will be used to define a region of space with respect to the LM, and the TR is located at that defined space. For example, for over (as discussed last week), the TR is located somewhere in a region that is defined relative to the LM using location a vertical axis(a projective relation…?) *[Sadalla et al., 1980 in Landau and Jackendoff article]

TR/LM -- asymmetry The cup is on the table
?The table is under the cup. The skateboard is next to the post. ?The post is next to the skateboard. What type of objects are typically used as LMs and TRs?: -- LMs = large, stable, familiar, or culturally significant objects. -- TRs = smaller, more mobile. If LMs are being used as reference points, need to know where they are located in the world… --In fact, find that LMs often exhibit similar prototype effects as other cognitive reference points – distance from “bad” LMs to “good” LMs is seen as less than the reverse* In language, the expression of spatial relations between objects are frequently not symmetrical. Two objects being related to one another may show up in different grammatical roles. - For example, in The cup is on the table. The cup is the subject and the table is the object of a preposition. We don’t usually get The table is under the cup. Or even with a seemingly symmetrical relation like next to, … [READ] Also get reaction time effects --linguistic tasks performed more quickly when using better (more fixed) LM and (mobile) TR than for reverse

Boundary Schema Roles: Boundary Region A Region B Region A Region B
The idea here is that a continuous region of space can be divided into two sub-regions when there’s a difference in values for some property or properties. In the drawing above, for example, the two regions are different colors, but we can differentiate areas on the basis of all sorts of properties, such as…???. The three main roles of this schema have been labeled Boundary, Region A and Region B. In a full schema description we’d want to say more… we’d want to at least add the restriction that Region A is different from Region B in some perceivable way. I’ve included drawings to help you understand the schemas, but a drawing always ends up specifying some things that aren’t actually specified by the schema. For example, the boundary here is shown as a straight line of a certain width and seems to be a separate object. But no separate boundary object need be present, nor does the boundary need to be of any particular shape. Boundary

Bounded Region Roles: Boundary: closed Bounded Region
Background region This is related to the Boundary schema, with the additional constraint that the boundary is a closed curve or surface. Bounded objects are type of bounded region. They are perceived as a Figure, distinct from the surrounding background region. Again though the drawing shows a circle, the bounded region could be of any shape.

Topological Relations
Separation Two bounded regions or objects can have various topological relations. These relations don’t make distinctions about actual sizes, distances, or shapes., and stay constant under various kinds of deformations, e.g. stretching, twisting… One such relation is separation -- no portion of either region, including the boundary, is immediately adjacent to or coincident with the other region. In the drawing here, each of the blue regions occupy different parts of space. -- because the two regions are separate, they can be perceived as distinct entities even if they share all the same properties -- separation is often bound to a proximal distal scale, allowing a distinction between objects which are very near to each other versus ones that are far apart.

Separation Contact Contact is a relation where some portion of the boundary of each of the regions are immediately adjacent, with no space between them. But, the two regions – the blue region and the yellow region-- still occupy different parts of space. -- When contact is perceived visually, it’s sometimes difficult to tell whether objects are actually contacting each other or whether they’re just very close to each other. -- But for force, contact is more readily distinguished from proximity since the transmission of force generally requires actual contact rather than just close proximity. So, for example, when we sense that something is exerting pressure on our skin, contact is present.

Separation Contact Coincidence: In the case of complete coincidence relation, the two regions occupy all of the same parts of space. In this drawing the green area is meant to indicate that the same area is occupied by blue and by yellow.

Separation Contact Coincidence: - Overlap It is also possible to have partial coincidence, or overlap Some of the blue and the yellow regions occupy the same part of space, but other parts do not.

Separation Contact Coincidence: Overlap Inclusion Or one region may be completely included in the other -- all of one region may occupy part of the space occupied by the other region. This is a more inherently asymmetrical relation than the previous topological relations, expressed as TR and LM. Yellow as TR and blue as LM rather than reverse, e.g. Yellow is in Blue or Blue includes Yellow

Separation Contact Coincidence: Overlap Inclusion Encircle/surround For the encircle or surround relation, the two regions occupy different areas of space, but one region completely surrounds the other… If you think of the blue region as a closed boundary, then it defines a bounded region of its own, and the yellow region is inside this bounded region but is not coincident with the blue region itself….

Orientation Vertical axis -- up/down up above upright below down
There is also a set of orientation schemas. These involve the notion of direction, which isn’t present in topological relations. The vertical axis is aligned with gravitic forces, as well as being a canonical orientation of the human body. --The vertical axis is usually defined with respect to the general scene, and doesn’t change for different viewpoints – it is external to the viewer. This is different than the distinctions we make along the horizontal plane, as we’ll see in a moment. --So the scene may have its own ‘inherent” structure, which isn’t imposed by the viewer. However, the viewer still has to be able to tell what a particular scene’s orientation is. --This can be done by orienting his own body thru internal mechanisms, such as thru his sense of equilibrium, and thru motor control interacting with gravity, and then orienting the scene relative to the self. --One can also use objects in the scene as cues, such as the canonical orientation of trees and the direction things fall when dropped [orientation can be used for single objects, or as a spatial relation between objects…] below down

Orientation Horizontal plane – Two axes:
The horizontal plane may be defined with respect to the vertical, e.g. once a person knows vertical/gravitic orientation, the horizontal is perpendicular to that. The surface of liquids is also an external guide. The horizontal plane may in turn be given axial structure. But gravity can’t be used as a cue to distinguish these axes [exception –when living on a hillside…]. Different languages have different ways of doing this, and utilizing different frames of reference. These can be divided into 3 main types – intrinsic, relative, and absolute.(following Levinson)

Language and Frames of Reference
There seem to be three prototypical frames of reference in language (Levinson) Intrinsic Relative Absolute

Intrinsic frame of reference
left back front For intrinsic, the different axes are determined with respect to inherent features of a person or object – For people, this correlates with parts of the body – particularly the face and front of the body vs. the back. So, I have a front and a back, and I can talk about objects being in front of me or behind me. This correlates too with perceptual asymmetry -- the front is usually more known and accessible, whereas the back is less so. For objects, intrinsic front/back may be determined by things like canonical direction of motion (e.g.cars) and interaction (e.g. TVs, computers, buildings). E.g. He sat in front of the TV for hours, The car is rolling backward. ---The right/left or side axis could be defined as perpendicular to the front/back axis. It lacks the asymmetries of the front/back axis, and in fact some languages, such as ?? do not distinguish between left and right Because these terms are usually used in relation to a canonical upright orientation of the human body, they correspond with the horizontal axes. -- it is a subject of research as to how people use these orientations when they are, for example, laying down…. And there are cross-linguistic differences as well…. ----Some languages, such as ???? use other types of figures, e.g.animal bodies in which case front (belly) will generally correspond with down, and back with up. (and orientation of figure doesn’t have to be canonical one) right

Relative frame of reference
right?? back front Relative frame of reference – some objects do not have an intrinsic “front” or “back” , e.g. balls, lamp posts, and trees. When using a relative frame of reference, front/back is assigned to object based on its relation to a viewer’s perspective. In English, this is done as if the object is facing you… But in other languages, e.g. the opposite may be the case. And how the sides are labelled is also variable… Might just be “sides” and in English, left right is relative to viewer, not object. Provides consistent logical inferences, unlike intrinsic system… left??

Absolute frame of reference
west south An absolute system doesn’t involve viewpoint or the inherent characteristics of the LM. Instead, they use the orientation of the landscape/”ground”… This may involve local geographic landmarks, such as mountains and shorelines. But it can also be fairly abstract, as in north east south west type systems which don’t change as one moves around in the landscape. [e.g. Tenejapan Tzeltal] For these systems, the description of a spatial array stays constant even as viewpoint changes (e.g. cup to the north of the plate). Like relative, preserves logical inference… north east

TR/LM and Verticality Schemas
The book is under the table. up Can combine schemas, e.g. the TR/Lm and the Verticality schema: As an example, let’s look at the sentence “The book is under the table”. In this example, the book is the trajector and the table is the landmark. The presumption is that we know where the table is. And we want to define a region of space relative to this LM. The specific region is defined by using another schema, which in this case might be called the “under” schema (which uses the vertical axis schema). A simple representation of this shows that the bluish trajector is more towards the “up” end of the vertical axis than the TR is. The TR is somewhere in the yellow area. Using this under schema, with the table as the LM, we then know that the book is somewhere in the yellow area… This is a just a simplified version of this… down under

Proximal/Distal Schema
. The proximal/distal schema relates to relative distance with reference to some landmark object. The default landmark here is usually the speaker, so proximal typically means proximal to speaker. This schema divides the area around the landmark into two or more zones. Different languages seem to make different numbers of distinctions. In English, we have near and far, can have more, e.g. something equivalent to “yon”. Proximal/distal distinctions are probably more than just an indication of spatial distance; they may reflect the differences in accessibility (both visual and manual) and affectedness that are correlated with changes in the distances between things. [give examples] Add something about peri-personal space?

Simple vs. Complex Schemas
So far I’ve gone over some of what might be called primitive or simple image schemas. And we’ve already seen that schemas can combine with one another. And in fact, most schematic structure we encounter in language involves fairly complex combinations of schemas. Also, in usage, we have values specified for some or all of the roles…. As an example of a potentially complex schema, let’s look at the Container schema… [next slide]

Container Schema Roles: Interior: bounded region Exterior Boundary C
The container schema can be described in terms of the bounded region schema, with the roles: …Interior, which is a bounded region Exterior Boundary This schema basically represents containers as bounded regions in space, with no restrictions on the size or shape of this region.

TR/LM + Container out in TR C C TR
When we add the TR/Lm schema, we can locate objects with respect to containers. Two basic (topological) relations are distinguished – either the TR in the interior region, or it is in the exterior region. Contact is not a factor here.

Container Schema Elaborated
Complexities –more roles/specifications: Boundary properties Strength Porosity Portals However, containers can be much more complex: And the relation between a container and its contents can be much more than a topological spatial relation. Physical containers are typically objects with a “hollow” interior and a solid boundary – they are used to hold and or protect other objects (the Contents). This means that most containers we interact with have force-dynamic properties as well. Specifically the boundaries (or sides) of the container provide some resistance to motion across or through them – this is how a container is able to contain something. --Consequently, we can talk about the strength of the containers’ s boundaries in terms of the amounts of force they can withstand without breaking. And porosity may also be a factor as to what a container can contain. --Also, containers typically have portals of some kind – a way for things to enter and exit the container. This means the boundary is not always completely closed and continuous.

Container schema logic
B A x The container schema is used for making inferences: if an object is in a container, it is not outside the container if X is in container A, and A is in container B, then X is in containerA Image schemas also often function as the source domain of metaphors. You might notice that this Classical categories are containers… -- categories have clear boundaries. -- An element is either in or out of the category. --Any location in the interior of the category qualifies as “in”. In this respect, all category members are equal. -And if X is a member of category A (Fido is a dog) and category A is in Category B (e.g. dogs are animals) then X is in category B (Fido is an animal)

Source-Path-Goal Constraints: initial = TR at Source
central = TR on Path final = TR at Goal To this point, the relations described have been static ones. But trajectors often move, and change location over time. The schema associated with moving Trajectors is the SPG To represent this will need to add different time stages – initial, central final And at each of these times the TR will be at a different location, e.g. TR starts at source, moves along Path and arrives at Goal. Though the Path here is shown as straight, any shape is possible… To make this meaningful, need to add one or more LMs in order to determine S P and/or G locations Source Path Goal

SPG -- simple example She drove from the store to the gas station.
TR = she Source = the store Goal = the gas station A very basic use of SPG Basic inferences – Initially she is closest to the store. As time progresses, she is further to the store and closer to the gas station. Once she is at the gas station, she has been at all the points on the path between the store and gas station. The Source PathGoal schema, like the basic TR/LM schema, can combine with all sorts of other schemas…. Source Path Goal

SPG and Container She ran into the room.
SPG. Source ↔ Container.Exterior SPG.Path ↔ Container.Portal SPG. Goal ↔ Container.Interior So for example, with SPG and container schema combined, can get She ran into the room. The room is conceptualized as a container, with a boundary and an interior. Initially, she is outside the room. At the final state, she is in the room. Somewhere in the central state, her path crossed the room boundaries (presumably through a door)

PATH landmarks LM LM LM past across along
The Path part of the SPG schema can also be related to a LM. --This can be a simple LM, as in The dog walked past the tree, where at some point in the motion, the dog is near the tree. --For many of the TR/Lm relations, the LM shape specification is irrelevant (exception – determining front/back relations…). However, dimensionality of the LM is sometimes relevant. E.g. containers are usually 2 or 3D, not points or lines) and contact is usually with the (2D) surface of an object. For some relations, the LM is a predominantly linear object (e.g. extent on main axis is greater than on other axes) e.g. Along and across a road -- Source and Goal are not specified. Could use same terms even if direction of Path was reversed… LM LM

Part-Whole Schema Part Whole
In addition to spatially relating two objects, image schemas can also be used to refer to a sub-region of an entity. A part-whole schema relates a portion of an entity to the entire whole entity. This could be combined with other schemas to refer to an oriented part. For example, we can talk about the front of the TV or the top of a tree. Whole

Representing image schemas
semantic schema Source-Path-Goal roles: source path goal trajector semantic schema Container roles: interior exterior portal boundary Boundary Interior Trajector Portal Source Goal Path Exterior These are abstractions over sensorimotor experiences.

Language and Spatial Schemas
People say that they look up to some people, but look down on others because those we deem worthy of respect are somehow “above” us, and those we deem unworthy are somehow “beneath” us. But why does respect run along a vertical axis (or any spatial axis, for that matter)? Much of our language is rich with such spatial talk. Concrete actions such as a push or a lift clearly imply a vertical or horizontal motion, but so too can more abstract concepts. Metaphors: Arguments can go “back and forth,” and hopes can get “too high.”

Simulation-based language understanding
Belief State General Knowledge Constructions construction WALKED form selff.phon  [wakt] meaning : Walk-Action constraints selfm.time before Context.speech-time selfm..aspect  encapsulated “Harry walked into the cafe.” Utterance Analysis Process Semantic Specification Similar to what we’re doing today (not coincidentally). Utterances evoke a complex network of conceptual schemas that are simulated in context to produce a rich set of inferences. BUT: entire process draws on many different kinds of data: constructions (lexical and grammatical, etc.), ontology, context. (We’re focusing on just a part of it today.) CAFE Simulation

The INTO construction construction INTO subcase of spatial-prep form selff .phon  [Inthuw] meaning evokes Trajector-Landmark as tl evokes Container as cont evokes Source-Path-Goal as spg tl.trajector « spg.trajector tl.landmark « cont cont.interior « spg.goal cont.exterior « spg.source Definition of constructions = form-meaning pairs needed? Standard?

Simulation specification
It should be clear that the simulation specification includes exactly the schematic content of the different elements of the sentence, bound appropriately. As noted earlier, the two representations differ with respect to which image schemas are involved – as reflected by the additional CONTAINER schema in Figure 5b – and in the precise bindings of aspects of the cafe to the SPG schema. Like the image schema representations, the simulation specifications can be viewed as a summary of the much more complex structures that are active when an event is simulated or imagined. Activating these structures – that is, “running” the simulation – can thus provide the much richer basis for inference necessary for accounting for many linguistic phenomena A simulation specification consists of: schemas evoked by constructions bindings between schemas

Basic Question about the role of Image Schemas
Are the spatial representations associated with certain verbs merely vestigial and only accessible metacognitively, or are they automatically activated by the process of comprehending those verbs?

Language and Thought Language We know thought (our cognitive processes) constrains the way we learn and use language Does language also influence thought? Benjamin Whorf argues yes Psycholinguistics experiments have shown that linguistics categories influence thinking even in non-linguistics task Thought cognitive processes

Universal Schemas and Cultural Frames
Image Schemas appear to be universal Colors Spatial schemas – container, support Action Schemas – grasp, general controller Frames are specific to a culture Commercial Transaction (CT), stock market Baseball, Cricket Linguistics, Philosophy Frames have roles and constraints like schemas. “shortstop” evokes the baseball frame framing has a major role in politics

Frames Frames are conceptual structures that may be culture specific
Words evoke frames The word “talk” evokes the Communication frame The word buy (sell, pay) evoke the Commercial Transaction (CT) frame. The words journey, set out, schedule, reach etc. evoke the Journey frame. Frames have roles and constraints like schemas. CT has roles vendor, goods, money, customer. Words bind to frames by specifying binding patterns Buyer binds to Customer, Vendor binds to Seller.

Event Frames Event frames have temporal structure, and generally have constraints on what precedes them, what happens during them, and what state the world is in once the event has been completed.

Sample Event Frame: Commercial Transaction
Initial state: Vendor has Goods, wants Money Customer wants Goods, has Money Transition: Vendor transmits Goods to Customer Customer transmits Money to Vendor Final state: Vendor has Money Customer has Goods

Sample Event Frame: Commercial Transaction
Initial state: Vendor has Goods, wants Money Customer wants Goods, has Money Transition: Vendor transmits Goods to Customer Customer transmits Money to Vendor Final state: Vendor has Money Customer has Goods (It’s a bit more complicated than that.)

Partial Wordlist for Commercial Transactions
Verbs: pay, spend, cost, buy, sell, charge Nouns: cost, price, payment Adjectives: expensive, cheap verbs. nouns and adjectives

Meaning and Syntax The various words that evoke this frame introduce the elements of the frame in different ways. , goods and money Information expressed in sentences containing these words occurs in different places in the sentence depending on the word.

An experiment on Image Schemas
Richardson and Spivey (2003) operationalized this question by presenting participants with sentences and testing for spatial effects on concurrent perceptual tasks. An interaction between linguistic and perceptual processing would support the idea that spatial representations are inherent to the conceptual representations derived from language comprehension (Barsalou, 1999).

Example verbs The servant argued with the master.
The storeowner increases the price. The girl hopes for a pony. The athlete succeeds at the tournament. The miner pushes the cart.

Aspect angles Vertical was 90 and horizontal 0.
Mean aspect angles were (12=H, 42=Neutral, 69=V)

Example verbs The servant argued with the master. 20 11 H
Forced choice Free form The servant argued with the master H The storeowner increases the price V The girl hopes for a pony V The athlete succeeds at the tournament V The miner pushes the cart H AVERAGE ASPECT ANGLE

The experiment Each trial began with a central fixation cross presented for 1000 ms. A sentence was presented binaurally through headphones. There was then a pause of 50, 100, 150 or 200 ms. This randomized “jitter” was introduced, so that participants could not anticipate the onset of the target visual stimulus. The target, a black circle or square, then appeared in either the top, bottom, left or right position, and remained on screen for 200 ms. Participants were instructed to identify the stimulus as quickly as possible, pressing one key to indicate a circle and another to indicate a square. Reaction times and accuracy rates were recorded. The questions were interrogative forms of the filler sentences with an object substitution in half of the cases (e.g., “Did the dog fetch the ball/stick?”). Participants responded “yes” or “no” by pressing designated keys.

Summary of Result There is an interference effect when the verb category is vertical (from norming study) and the visual stimulus object is vertical. Issues with the experiment?

Experiment on Memory effect

Action Words- an fMRI study
Somatotopic Representation of Action Words in Human Motor and Premotor Cortex Olaf Hauk, Ingrid Johnsrude,and Friedemann Pulvermuller* Medical Research Council, Cognition and Brain Sciences Unit Cambridge, United Kingdom Neuron, Vol. 41, 1–20, January 22, 2004, Copyright by Cell Press

Traditional theory Unified meaning center in the left temporal lobe.
Connected to Wernicke’s area Experiments on highly imageable words/nouns. Vocalization and grammar associated with frontal lobe Connected to Broca’s area

Do action words activate the motor cortex
Given: Cortical representations of the face, arm, and leg are discrete and somatotopically organized in the motor and premotor cortex Hypothesis: Words referring to actions performed with the face, arm, or leg would activate premotor networks. neurons processing the word form and those processing the referent action should frequently fire together and thus become more strongly linked, resulting in word-related networks overlapping with motor and premotor cortex in a somatotopic fashion. Experiment: An fMRI study with word stimuli from different effectors (face, arm, or leg). ROI based on movements (face, arm, leg)

Somatotopy in STS and MC

The Experiment In order to find appropriate stimulus words, a rating study was first performed. Subjects were asked to rate words according to their action and visual associations and to make explicit whether the words referred to and reminded them of leg, arm, and face movements that they could perform themselves From the rated material, 50 words from each of the three semantic subcategories were selected and presented in a passive reading task to 14 right-handed volunteers, while hemodynamic activity was monitored using event-related fMRI. The word groups were matched for important variables, including word length, imageability, and standardized lexical frequency, in order to minimize physical or psycholinguistic differences that could influence the hemodynamic response. To identify the motor cortex in each volunteer individually, localizer scans were also performed, during which subjects had to move their left or right foot, left or right index finger, or tongue.

Norming (B) Mean ratings for the word stimuli obtained from study participants. Subjects were asked to give ratings on a 7 point scale whether the words reminded them of face, arm, and leg actions. The word groups are clearly dissociated semantically (face-, arm-, and leg-related words).

All Actions (C) Activation produced by all action words pooled together. Results are rendered on a standard brain surface (left) and on axial slices of the same brain (right).

Movement vs. Actions

Correlation with BOLD Signal

Action Word Movement Overlap

Neural Evidence for category structure
Are there specific regions in the brain to recognize/reason with specific categories? No, but there are specific circuits distributed over relevant regions of the brain. What might the general characteristics of such circuits look like?

Schemas and Frames in Language
Language Understanding Model Analysis Semantic Specification Enactment or Simulation Semantic Specification (SemSpec) Combines Schemas and Frames Links (bindings) determine particular meaning Enactment Based on system goals Uses SemSpec and world knowledge

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