psy 369: psycholinguistics language comprehension

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PSY 369: Psycholinguistics Language Comprehension

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PSY 369: Psycholinguistics

Language Comprehension

Some of the big questions

“the horse raced past the barn”

Production

How do we turn our thoughts into a spoken or written output?

Some of the big questions

Comprehension

“the horse raced past the barn”

How do we understand language that we hear/see?

How do we turn our thoughts into a spoken or written output?

Production

Some of the big questions Comprehension Production Representation

How do we store linguistic information? How do we retrieve that information?

Lexicon

SemanticAnalysis

SyntacticAnalysis

WordRecognition

Letter/phonemeRecognition

FormulatorGrammatical EncodingPhonological Encoding

Articulator

Conceptualizer

Thought

Lexicon

SemanticAnalysis

SyntacticAnalysis

WordRecognition

Letter/phonemeRecognition

FormulatorGrammatical Encoding

Phonological Encoding

Articulator

Conceptualizer

Thought

Overview of comprehension

The cat chasedthe rat.

Input

cat

dogcapwolftreeyarncat

clawfurhat

Wordrecognition

Language perception

ca

t

/k//ae/

/t/

Syntacticanalysis

cat

S

VP

ratthe

NP

chased

Vthe

NP

Semantic &pragmaticanalysis

The Comprehender’s Problem

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

The Comprehender’s Problem

If reading were like listening

whereareyougoing

Different signals Reading and listening are very different

Where are you going?

Different speakers speak differentlyLots of differences in written/printed language

The Comprehender’s Problem

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

The cat chased the rat.

The cat chased the rat.

The cat chased the rat.

The cat chased the rat.

The Comprehender’s Problem

I scream for ice scream

The stuffy nose can lead to problems.The stuff he knows can lead to problems.

Oronyms

Why don’t you take a nice cold shower?Why don’t you take an ice cold shower?

See here for more oronyms

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

The Comprehender’s Problem

Good shot How he got into my pajamas I’ll never know

Groucho Marx shot an elephant in his pajamas

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

The Comprehender’s Problem

Money “bank” River “bank”

“Oh no, Lois has been hypnotized and is jumping

off the bank!”

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

The Comprehender’s Problem

“Uncle Bobkicked the bucket

last night”

“Sure as soon as I’m done using it.”

“Nope, somebody glued it to the table.”

Ambiguity Must take a potentially ambiguous serial acoustic

(or visual) input, and recover the intended meaning

“Can you pass the salt”

Overview of comprehension

The cat chasedthe rat.

Input

catdogcapwolftreeyarncat

clawfurhat

Wordrecognition

Language perception

ca

t

/k//ae/

/t/

Syntacticanalysis

cat

S

VP

ratthe

NP

chased

Vthe

NP

Semantic &pragmaticanalysis

Lexical Access

Lexical access How do we retrieve the linguistic

information from Long-term memory? How is the information organized/stored? What factors are involved in retrieving

information from the lexicon? Models of lexical access

Lexical access How do we retrieve the linguistic

information from Long-term memory? How is the information organized/stored? What factors are involved in retrieving

information from the lexicon? Models of lexical access

Storing linguistic information Tale of the tape:

High capacity: 40,000 – 60,000 words Fast: Recognition in as little as 200ms (often before word

ends) How do we search that many, that fast!? – suggests that there is a high

amount of organization

Excellent reading: Words in the Mind, Aitchison (1987, 2003)

Or something much more complex

“The world’s largest data bank of examples in context is dwarfed by the collection we all carry around subconsciously in our heads.”

E. Lenneberg (1967)

Storing linguistic information Interesting questions:

How are words stored? What are they made up of? How are words related to each other? How do we use them?

Some vocabulary Mental lexicon The representation of words in long term memory Lexical Access: How do we access words and their the meanings

(and other properties)?

Theoretical Metaphors: Access vs. Recognition

Recognition - finding the representation

Often used interchangeably, but sometimes a distinction is made

Here it is

dogcapwolftreeyarncat

clawfurhat

Search for a match

cat

Select word

cat

cat

catThe magic moment

Balota (1990)

Theoretical Metaphors: Access vs. Recognition

Access - getting information from the representation

Recognition - finding the representation

Often used interchangeably, but sometimes a distinction is made

Open it up and see what’s inside

dogcapwolftreeyarncat

clawfurhat

Search for a match

cat

Select wordAccess lexical

information

CatnounAnimal, pet,Meows, furry,Purrs, etc.

cat

Lexical access How do we retrieve the linguistic

information from Long-term memory? How is the information organized/stored? What factors are involved in retrieving

information from the lexicon? Models of lexical access

Studying Lexical Access Generally people ask: what makes word

identification easy or difficult? The assumption:

Measures of identification time are usually indirect Time spent identifying a word can be a measure of

difficulty

Common methodologies Measure how long people take to say a string of

letters is (or is not) a word (lexical decision) Measure how long people take to categorize a word

(“apple” is a fruit) Measure how long people take to start saying a word

(naming or pronunciation time) Measure how long people actually spend looking at a

word when reading Word by word reading Line by line reading Using eye movement monitoring techniques

Lexical accessFactors affecting lexical access

Some of these may reflex the structure of the lexicon

Some may reflect the processes of access from the lexicon

Words or morphemes? Word primitives

Morpheme primitives Economical - fewer representations Slow retrieval - some assembly required

Decomposition during comprehension Composition during production

Need a lot of representations Fast retrieval

horse horses barn barns

horse -s barn

Words or morphemes? Lexical Decision task (e.g., Taft, 1981)

See a string of letters As fast as you can determine if it is a real

English word or not “yes” if it is “no” if it isn’t

Typically speed and accuracy are the dependent measures

table

vanue

daughter

tasp

cofef

hunter

Words or morphemes? Lexical Decision task

tablevanue

daughtertaspcofefhunter

YesNo

YesNoNoYes

Words or morphemes? Lexical Decision task

daughter

hunter

Words or morphemes? Lexical Decision task

daughter

hunter

Pseudo-suffixed

Multimorphemic

daught

hunt -er

-er

Takes longer

This evidence supports the morphemes as primitives view

Words or morphemes? May depend on other factors

What kind of morpheme Inflectional (e.g., singular/plural, past/present tense) Derivational (e.g., drink --> drinkable, infect --> disinfect)

Frequency of usage High frequency multimorphemic (in particular if derivational

morphology) may get represented as a single unit e.g., impossible vs. imperceptible

Compound words Semantically transparent

Buttonhole Semantically opaque

butterfly

Phonology

Words that sound alike may be stored “close together”

What word means to formally renounce the throne?

abdicate

Brown and McNeill (1966) Tip of the tongue phenomenon (TOT)

Look at what words they think of but aren’t right

e.g, “abstract,” “abide,” “truncate”

Phonology

Letters at Word beginning

Word end

10

2 3 3 2 1

20

30

40

50

1

% o

f m

atch

es

Similar-meaning words

Similar-sounding words

More likely to approximate target words with similar sounding words than similar meanings

The “Bathtub Effect” - Sounds at the beginnings and ends of words are remembered best (Aitchison, 2003)

Words that sound alike may be stored “close together” Brown and McNeill (1966) Tip of the tongue phenomenon (TOT)

Imageability Imageability, concreteness, abstractness

Umbrella

Lantern

Freedom

Apple

Knowledge

Evil

Try to imagine each word

Imageability Imageability, concreteness, abstractness

Umbrella

Lantern

Freedom

Apple

Knowledge

Evil

Try to imagine each word

How do you imagine these?

Imageability Imageability, concreteness, abstractness

Umbrella

Lantern

Freedom

Apple

Knowledge

Evil

More easily remembered

More easily accessed

Frequency

GambastyaReveryVoitleChardWefeCratilyDecoyPuldowRaflot

MulvowGovernorBlessTugletyGareReliefRuftilyHistoryPindle

Lexical Decision Task:

OrioleVulubleChaltAwrySignetTraveCrockCrypticEwe

DevelopGardotBusyEffortGarvolaMatchSardPleasantCoin

Frequency

GambastyaReveryVoitleChardWefeCratilyDecoyPuldowRaflot

MulvowGovernorBlessTugletyGareReliefRuftilyHistoryPindle

Lexical Decision Task:

OrioleVulubleChaltAwrySignetTraveCrockCrypticEwe

DevelopGardotBusyEffortGarvolaMatchSardPleasantCoin

Low frequency High(er) frequency

Typically the more common a word, the faster (and more accurately) it is named and recognized

Typical interpretation: easier to access (or recognize)

Frequency

However, Balota and Chumbley (1984) Frequency effects depend on task

Lexical decision - big effect Naming - small effect Category verification - no effect

A canary is a bird. T/F

Typically the more common a word, the faster (and more accurately) it is named and recognized

Typical interpretation: easier to access (or recognize)

Semantics Free associations

Most associates are semantically related (rather than phonologically for example)

Semantic Priming task Meyer & Schvaneveldt (1971)

For the following letter strings, decide whether it is or is not an English word

TaspNurseDoctorFractSlithestShoesDoctor

noyesyesnonoyesyes

nurse

shoes

Responded to fasterRelated

Unrelated

“Priming effect” Evidence that associative relations influence lexical access

doctor

doctor 940 msecs

855 msecs

Role of prior context

Cross Modal Priming Task:

Listen to short paragraph. At some point during theparagraph a string of letters will appear on the screen. Decide if it is an English word or not. Say ‘yes’ or ‘no’ as quickly as you can.

Role of prior context

ant

“Rumor had it that, for years, the government building has been plagued with problems. The man was not surprised when he found several spiders, roaches and other

bugs in the corner of his room.”

Role of prior context Swinney (1979)

Lexical Decision taskContext related: antContext inappropriate: spyContext unrelated: sew

Results and conclusions Within 400 msecs of hearing "bugs", both ant and spy are

primed After 700 msecs, only ant is primed

“Rumor had it that, for years, the government building has been plagued with problems. The man was not surprised when he found several spiders, roaches and other

bugs in the corner of his room.”

Lexical ambiguity Hogaboam and Pefetti (1975)

Words can have multiple interpretations The role of frequency of meaning

Task, is the last word ambiguous? The jealous husband read the letter (dominant meaning) The antique typewriter was missing a letter (subordinate meaning)

Results: Participants are faster on the second sentence.

The results may seem counterintuitive The task is the key, “is the final word ambiguous” In the first sentence, the meaning is dominant and the context strongly

biases that meaning. So the second meaning may not be around, which in turn makes the it harder to make the ambiguity judgment in the first sentence

Lexical access How do we retrieve the linguistic

information from Long-term memory? How is the information organized/stored? What factors are involved in retrieving

information from the lexicon? Models of lexical access

Models of lexical access Serial comparison models

Search model (Forster, 1976, 1979, 1987, 1989) Parallel comparison models

Logogen model (Morton, 1969) Cohort model (Marslen-Wilson, 1987, 1990)

Connectionist models Interactive Activation Model (McClelland and Rumelhart,

1981)

Logogen model (Morton 1969)Auditory stimuli

Visual stimuli

Auditory analysis

Visual analysis

Logogen system

Outputbuffer

Context system

Responses

Available Responses

Semantic Attributes

Logogen model

The lexical entry for each word comes with a logogen

The lexical entry only becomes available once the logogen ‘fires’

When does a logogen fire? When you read/hear the word

Think of a logogen as being like a ‘strength-o-meter’ at a fairground

When the bell rings, the logogen has ‘fired’

‘cat’[kæt]

• What makes the logogen fire?

– seeing/hearing the word

• What happens once the logogen has fired?

– access to lexical entry!

– High frequency words have a lower threshold for firing

–e.g., cat vs. cot

‘cat’[kæt]

• So how does this help us to explain the frequency effect?

‘cot’[kot]

Low freq takes longer

• Spreading activation from doctor lowers the threshold for nurse to fire

– So nurse take less time to fire

‘nurse’[nə:s]

‘doctor’[doktə]

nurse

doctor

Spreading activation network

doctor nurse

Search modelE

ntri

es in

ord

er o

f

Dec

reas

ing

freq

uenc

yVisual input

cat

Auditory input

/kat/

Access codes

Pointers

mat cat mouseMental lexicon

Cohort model Specifically for auditory word recognition

(covered in chapter 9 of textbook) Speakers can recognize a word very rapidly

Usually within 200-250 msec Recognition point (uniqueness point) - point at

which a word is unambiguously different from other words and can be recognized

Three stages of word recognition1) activate a set of possible candidates2) narrow the search to one candidate3) integrate single candidate into semantic and

syntactic context

Cohort model Prior context: “I took the car for a …”

/s/ /sp/ /spi/ /spin/

…soapspinachpsychologistspinspitsunspank…

spinachspinspitspank…

spinachspinspit…

spin

time

Interactive Activation Model (IAM)

McClelland and Rumelhart, (1981)

Nodes: • (visual) feature• (positional) letter• word detectors

• Inhibitory and excitatory connections between them.

Previous models posed a bottom-up flow of information (from features to letters to words).

IAM also poses a top-down flows of information

Inhibitory connections within levels If the first letter of a word is “a”, it isn’t “b” or “c” or …

Inhibitory and excitatory connections between levels (bottom-up and top-down)

If the first letter is “a” the word could be “apple” or “ant” or …., but not “book” or “church” or……

If there is growing evidence that the word is “apple” that evidence confirms that the first letter is “a”, and not “b”…..

Interactive Activation Model (IAM)

+

Until the participant hits some start key

The Word-Superiority Effect (Reicher, 1969)

COURSE

Presented briefly … say 25 ms

The Word-Superiority Effect (Reicher, 1969)

U &&&&&

A

Mask presented with alternatives above and belowthe target letter … participants must pick one as theletter they believe was presented in that position.

The Word-Superiority Effect (Reicher, 1969)

The Word-Superiority Effect (Reicher, 1969)

+

E E

& T

+

PLANE E

&&&&& T

+

KLANE E

&&&&& T

Letter only Say 60%

Letter in Nonword Say 65%

Letter in Word Say 80%

Why is identification better when a letter is presented in a word?

IAM & the word superiority effect

We are processing at the word and letter levels simultaneously Letters in words benefit from bottom-up and top-

down activation But letters alone receive only bottom-up activation.

Comparing the models Each model can account for major findings (e.g.,

frequency, semantic priming, context), but they do so in different ways. Search model is serial and bottom-up Logogen is parallel and interactive (information

flows up and down) Cohort is bottom-up but parallel initially, but then

interactive at a later stage AIM is both bottom-up and top-down, uses

facilitation and inhibition