Cognitive Psychology Chapter 9a Language

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Study Questions.• How has sentence ambiguity been used to study the psycholinguistics of grammar.• Describe the classical localization model of brain and language. How do different aphasias relate to the model. Give examples.

04/10/23Oh freddled guntbuggly, thy micturations are to meAs plurdled gabbleblothchits on a lugid beeGroop, I implore thee, my foonting turlingdromesAnd booptiously drangle me with crinkly bindlewurdlesOr I will rend thee in the gobberwarts With my blurglecruncheon, see if I don’t

Prostetnic Vogon JeltzHitchhiker’s Guide to the Galaxy

• Language» Articulatory Phonetics

◊ Top down processes

» Syntax

» Lexical and semantic factors◊ Case Grammar

» Neuropsychology of language◊ Classical Localization Model

» Neurophysiology of language

Language

• Articulatory Phonetics» Voicing

Perc

enta

ge I

dent

ifie

d

100

80

60

40

20

0

Voice-onset time (ms)40 50 60 7010 20 30

Language

• Is speech special?» Do we possess specialized neural mechanisms for

perceiving speech? » Categorical perception

◊ Voice onset-time and distinguishing /d/ from /t/

Language

• Articulatory Phonetics

» Vowels◊ Positioning and part of tongue

– Height

High (/i/ beet)

Med (/e/ bait)

Low (/a/ pot)

– Part

Front (/I/ bit)

Central (but)

Back (/o/ boat)

Language

• The search for invariants

» Distinctive features

» Problems with a simple bottom-up approach◊ There are no periods of silence between phonemes

– The speech spectrograph

Language

• The search for invariants

Language

• The search for invariants» Phonemic information is presented in parallel

◊ Coarticulation◊ E.g. Cf. /M/ in “Tim” vs. “/M/ in “mad”

» We perceive them as the same, but they are different

» We perceive the same sound differently according to the context

◊ E.g.: Writer vs. Rider

◊ E.g.: Insert a silence between /s/ and /i/ --> “ski”

Insert a silence between /s/ and /u/ --> “spew”

Language

• Top down processes» Phonemic restoration effect (Warren, 1970)

◊ Their respective legi*latures◊ Found a *eel on the axle◊ Found a *eel on the shoe

Language

• Perceiving conversational speech» Two main problems:

◊ There are no physical boundaries between words– Anna Mary candy lights since imp pulp lay things

– ( An American delights in simple play things)

◊ Speech is sloppy– He wants to kiss this Guy?

– Misheard Lyrics (www.kissthisguy.com)

– This was the best buy vs. She is a bad girl

Language

• Perceiving conversational speech

Language

W h a d’ a y a D oo w i n

• Perceiving conversational speech

Language

• Top-down processes and speech perception

» Phonemic perception◊ The McGurk Effect

» Sentence comprenension◊ Miller & Isard (1963)

– Participants shadow sentences:

Grammatic: Bears steal honey from the hive.

Semantically incorrect: Bears shoot honey on the highways.

Ungrammatic: Across bears eyes honey the bill.

Language

• Top-down processes and speech perception◊ Miller & Isard (1963)

– Results

Gram. Nonsem. Nongram.

No noise 89% 79% 56%

Noise 63% 22% 3%

Language

• Syntax» Finite state grammar

◊ E.g, Miller (1958).

0

1

3 2

0´StartFinish

S

N

N X

S

G

G

X

Language

• Syntax» Finite state grammar

◊ E.g, Miller (1958).

Structured Random

L1 L2 R1 R2

SSXG NNSG GNSX NXGS

NNXSG NNSXG NSGXN GNXSG

SXSXG SXXSG XGSSN SXNGG

Etc. Etc. Etc. Etc.

Language

• Syntax» Finite state grammar

◊ E.g, Miller (1958).

Language

• Syntax» Finite state grammar

◊ Problems with finite state grammar– Linguistic competence

– Judgements of grammaticity (Chomsky)

e.g., Colourless green ideas sleep furiously

(For words never paired together)

– Judgements of agrammaticity (Miller and Selfridge)

e.g., Was he went to the newspaper is in deep end.

(For words often paired together)

– Resolving/explaining ambiguity

e.g., They are cooking apples.

Language

• Syntax» Phrase structure grammar

» Constituent analysis

The boy hit the ball

Verb phrase (VP)Noun phrase (NP)

NPDet.

The

Det.

the

Noun

boy

Verb

hit

Noun

ball

Sentence

VPNP

Verb NP

Cop. Part. Noun

Pronoun

They flyingare planes

Sentence

VPNP

They

Pronoun Verb NP

NounAdj

flyingare planes

Language

• Syntax» Phrase structure grammar

◊ Three types of sentences– Grammatical / meaningful: maps onto only one phrase structure.

– Nongrammatical: cannot be mapped onto a phrase structure

– Grammatical / ambiguous: maps onto more than one phrase structure.

e.g., They are flying planes

Language

• Syntax» Transformational grammar

◊ Some ambiguous sentences are not explained by phrase structure

E.g, Visiting relatives can be boring

◊ Both interpretations map onto the same phrase structure...but, they map onto different meanings

» Surface structure: Superficial appearance (i.e., phrase structure).

» Deep structure: The meaning of the sentence.

» Transformational rules: convert the deep structure into a surface structure (a sentence ready to be spoke)

Language

• Syntax» Resolving ambiguity (McKay, 1966)

◊ Lexical ambiguity– E.g., Although he was continually bothered by the cold …

– Control: headache

◊ Surface ambiguity– E.g., Although Hannibal sent troops over a week ago …

– Control: almost

◊ Underlying ambiguity– E.g., Knowing that visiting relatives could be bothersome ….

– Control: visiting some

Language

• Syntax» Resolving ambiguity (McKay, 1966)

◊ Results

Language

• Syntax» Case grammar

◊ Semantic analysis involves determining the semantic role of each word or concept and computing sentence meaning based on that analysis.

◊ E.g,A] The key will open the door

B] The janitor will open the door with the key

– The ‘key’ is the subject of [A] and an object in [B] but serves the same role in each sentence.

Language

• Syntax» Interaction between syntax and semantics

◊ Fillenbaum (1974)– Had subjects read and then paraphrase several sentences– Normal sentences:

Threat: Don’t print that or I will sue you.Control: John got off the bus and went to the store

– Perverse/disorderedThreat: Don’t print that or I won’t sue youControl: John went in the store and got on the bus.

– Results:Perverse: 50% normalized in their paraphrasesDisordered: 60 % normalized.When subjects checked their work, they missed

half of the errors…

Nice we’re having weather isn’t it?

Brain & Language

• Neuropsychology of language» Aphasia: Language deficits resulting from brain-related

disorders and injury.◊ Very common

– 40 % of all strokes produce some aphasia

» Broca’s Aphasia◊ Paul Broca - studied patient Leborgne (A.K.A.’Tan’)

– Treated for leg injury

– Died a few days later

– Autopsied brain

– Discovered ‘Broca’s area’

– Left Hemisphere dominance for language

Brain & Language

• Neuropsychology of language» Broca’s Aphasia

Paul Broca

Brain & Language

• Neuropsychology of language» Broca’s Aphasia

◊ Production Deficits

– Problems in producing fluent language

– Range from ‘Tan,tan,tan,…’ to short phrases

– Lack function words and grammar

May retain idioms (‘fit as a fiddle’) or songs

– Proximity to motor cortex

Dysarthria: loss of control over articulatory muscles

Speech Apraxia: Unable to program voluntary articulatory movements.

Paul Broca

Brain & Language

• Neuropsychology of language» Broca’s Aphasia

◊ Comprehension deficits– Unable to analyze precise grammatical information

E.g.

“The Boy ate the cookie”

Who ate the Cookie?

“Boy ate cookie”

Implied grammar (cookies don’t eat boys)

“The Boy was kicked by the girl”

Who kicked whom?

“Boy kick girl”

Paul Broca

Brain & Language

• Neuropsychology of language» Wernicke’s Aphasia

◊ Carl Wernicke, 1870s

– Examined two patients

Problems understanding language following strokes

Fluent but nonsensical speech

Poor language comprehension

Proximity to auditory sensory areas

(Wernicke proposed word memory area)

Carl Wernicke

Brain & Language

• Neuropsychology of language» Wernicke’s Aphasia

◊Production deficits– Sounds fluent (e.g., foreign language)

– Neologistic (invented words)

– Semantic substitutions

E.g.

I called my mother on the television and did not understand the romers by the door.

Carl Wernicke

Brain & Language

• Neuropsychology of language» Wernicke’s Aphasia

◊Comprehension deficits– Do not recognize the incomprehensibility of their own

sentences

– Do not comprehend written or spoken language

◊“Here and gone again”– Aphasia improves over time

– Anomia: Losing the ability to retrieve words (nouns)

Carl Wernicke

Brain & Language

• Neuropsychology of language» Classical localization model (Lichtheim, 1885; Geschwand,

1967)

ConceptualInformation

Wernicke’sBroca’s

Brain & Language

• Neuropsychology of language» Classical localization model (Lichtheim, 1885; Geschwand,

1967)

◊ Damage to main areas– Broca’s Aphasia

– Wernicke’s Aphasia

◊ Damage to connections– Conduction aphasia

– Transcortical sensory aphasia

Brain & Language

• Neuropsychology of language» Conduction aphasia

◊ Damage to the connection between Wernicke’s and Broca’s area

– Arcuate Fasciculus

Brain & Language

• Neuropsychology of language» Conduction aphasia

◊ Production deficits– Problems producing spontaneous speech

– Problem repeating speech

– Sometimes use words incorrectly

◊ Comprehension– Can understand spoken/written words

– Can hear their own speech errors, but cannot correct them

Brain & Language

• Neuropsychology of language» Conduction aphasia

ConceptualInformation

Wernicke’sBroca’s

Brain & Language

• Neuropsychology of language

» A prediction

ConceptualInformation

Wernicke’sBroca’s

Brain & Language

• Neuropsychology of language

» A prediction◊ Disconnecting Wernicke’s from the conceptual area

should lead to repetition without comprehension.◊ Transcortical Sensory Aphasi

– Damage to the angular gyri

Brain & Language

• Neurophysiology of language in the intact brain

» ERP studies◊ The N400: Semantic violations

Brain & Language

• Neurophysiology of language in the intact brain

» ERP studies◊ The P600: Syntactic Positive Shift (syntactic violation)

Brain & Language

• Neurophysiology of language in the intact brain◊ Dispreferred continuation of ambiguous sentences

– E.g.,

The spy saw the cop with the binoculars

Who has the binoculars?

“The spy has the binoculars” -> preferred continuation

◊ The N400 and aphasia– Swaab et al.

Patients listened to sentences that had an anomalous word at the end.

Brain & Language

• Neurophysiology of language in the intact brain◊ Swaab et al. (1997)

Brain & Language

• Neurophysiology of language in the intact brain◊ A caveat: Individual differences

– Stimulation mapping of the brain

Neurosurgery around left hemisphere language areas

– A couple hundred of partients

– Correlation with effects in Wernicke and Broca’s area are week

Some patients have naming problems in the area, not all.

– Anatomical localizations vary considerably.

Brain & Language

• Neurophysiology of language in the intact brain

◊ A caveat: Individual differences