Language II October 15, 2009
Dec 27, 2015
Language II
October 15, 2009
Why is Language Important?
• Represents unique form of abstraction in human species
• Language influences perception and memory
• Relevant to the form and manner of information storage
• Relevance to thinking and problem-solving is unquestioned
• Chief means of human communication
Key Terminology• Phonology: (the way sounds function in the language)
basic unit = phoneme– single speech sound– English has about 45; 9 make up half our words– dimensions: voiced (“a”); unvoiced (“s”); fricatives
(“sh”), plosives (“t”); place of articulation (palate v. lips)
• Morphology: (study of the internal structure of words) basic unit = morpheme– smallest unit of meaning (words, parts of words, etc.)– free (e.g., “old”, “the”) vs. bound (e.g., “er”, “ist”)– over 100,000 words formed by morpheme
combinations• Semantics: (study of meaning)
– denotation vs. connotation – e.g., “heart”– words as economic labels; link between language
and concepts• Syntax: (study of rules that govern combination of
morphemes in phrases and sentences; interdependency)– prescriptive vs. descriptive grammar– “Daddy, what did you bring that book that I don’t
want to be read to out of up for”?
Language Comprehension
Auditory Word Recognition: Basic Processes
• Bottom-up: processing of individual phonemic features
• Top-down: conceptual processing– phonemic restoration effect:
• probably affects response bias, not sensitivity
“the *eel was on the axle” - hear “wheel”“the *eel was on the shoe” - hear “heel”“the *eel was on the orange” - hear “peel”
Theories of Auditory Word Recognition I• Motor Theory of Speech Perception (Liberman et
al., 1967)– during listening, listeners mimic articulatory
movements of speaker and depend on this for recognition
– Supported by PET studies showing motor activation during speech perception
– noninvariance is a problem, as is infant data• Cohort Theory (Marslen-Wilson & Tyler, 1980)
– activation of word cohort as speech signal arrives– some activated words eliminated on basis of context;
continues until “recognition point” is achieved– assumes that lexical, syntactic, and semantic
information interact to analyze speech signal; context effects are probably late• e.g., “The police indicated that excessive SP---
was a factor in the fatal accident.”
Auditory Word Recognition: Theories II
• TRACE Model (McClelland, 1991)– three units of levels: features,
phonemes, words– between-level connections excitatory– within-levels inhibitory– excitation in the network produces
pattern, or “trace” of activation– recognized word is that which is
highest among candidate words
A Simple Feature-Detection Network
Auditory Word Recognition: Theories III
• Cognitive Neuropsychological Models– derive from studies of how word recognition
fails after brain injury– make use of “box models” of cognitive
processing popular in mainstream cognitive psychology
– basic structural features:• domain-specific systems• lexicons
Model of Processes involved in Analysis of Spoken Words
Normally, all routes are available; damage to system reveals fractionated performance which serves to “isolate” each route to a greater or lesser degree
Route 1: accesses full representation of word, including meaning and spoken form
Route 2: same as route 1 without meaning
Route 3: involves phoneme-spoken form conversion (e.g., for repetition)
Pattern 1: ORFRepeats words (85%) better than nonwords (39%), but can understand familiar words
Pattern 2: Word-meaning deafness – can repeat but not understand; can repeat words (80%) better than nonwords (7%); can understand written words
Pure Word Deafness
Stages in Lexical Processing (Single Word Recognition)
• Contact of the analyzed waveform with the lexicon– Spectrographic (LAFS)– Motor theory– Phonemic theories
• Activation of specific lexical entries • Selection of appropriate lexical entry
from set of activated candidates• Access to the full information from the
lexical entry
Reading (Visual Word Comprehension)
• Similar processes likely, but entry into the system is a visual (graphemic), not an acoustic (phonemic) representation
• Transformation from graphemes to phonemes is critical
• Two routes to reading– Grapheme-phoneme conversion– Lexical (whole word) reading
How Reading is Studied
• Eye movement recordings• Reading aloud• RSVP (rapid serial visual
presentation)• Subject-controlled presentation• Word-identification techniques
– lexical decision– naming
Eye-Movement Research• Emphasizes a “word-recognition” vs. “meaning construction”
approach to reading• Asymmetric perceptual span (3-4 letters to the left of fixation
and 15 letters to the right)• Parafoveal preview allows for skipping words• Fixations may be affected by context and meaning
– predictable words receive less fixation– “garden path” sentences:
“The young man turned his back on the rock concert stage and looked across the resort lake. Tomorrow was the annual one-day fishing contest and fishermen would invade the place. Some of the best bass guitarists would come to this spot”
– derivation of meaning occurs early (parafoveally? instantaneously?)
Fixation data from a normal (PP) and a dyslexic (Dave) reader
Numbers immediately below the dots are the sequence of eye movements, and the lower numbers are fixation times
Visual Word Identification
• Rapid (200ms)• Automatic (e.g., Stroop effect)• Basic effects:
– word-letter effect: letters identified better if in words than if alone (e.g., TAKE v. _ _ K _)
– word-superiority effect: letters identified better when in real word (e.g., TAKE v. PAKE)
– These effects imply that “word environment” influences recognition
red green blue
green yellow red
blue green blue
red yellow green
yellow red blue red
Visual word recognition is automatic…..
Visual Word Identification: Models I
• Serial Letter Model
.
.• Parallel Letter Model
Visual
ProcessingLetter Detection Word Detection
Visual
Processing
Letter Detectors Word Detectors
Visual Word Identification: Models II
• Direct Word Model
• Interactive Activation Model
Visual Processing
Letter Detection
Word Detection
Visual
Input
Feature Analysis
Letter Analysis
Word Analysis
McClelland & Rumelhart’s Interactive Activation Model
Cognitive Neuropsychological Model of Processes
involved in Reading – the “Dual Route
Cascaded Model” (Coltheart, et al 2001)
Example from book:
CAT FOG COMB PINT MANTINESS
FASS
Route 1 (Grapheme–Phoneme Conversion)
• Converting spelling (graphemes) into sound (phonemes)
• Marshall and Newcombe (1973)– Surface dyslexia – poor reading of irregular
words; strong reliance on Route 1• McCarthy and Warrington (1984)
– KT read 100% of nonwords accurately, and 81% of regular words, but was successful with only 41% of irregular words
– Over 70% of the errors that KT made with irregular words were due to regularisation
• Significant variability in performance, suggesting that this is not a clear dissociation
Phonological Awareness
Route 2 (Lexicon Plus Semantic System)
• Event sequence– Representations of familiar words are stored
in an orthographic input lexicon; activation leads to…
– Meaning is activated by the semantic system and..
– Sound pattern is generated in the phonological output lexicon
• Beauvois and Dérouesné (1979)– Phonological dyslexia – impaired Route 1;
use Route 2; 100% real words; 10% nonwords
Route 3 (Lexicon Only)
• Like Route 2 but the semantic system is bypassed – printed words are pronounced but not understood
• Funnell (1983)– Phonological dyslexia with poor ability to
make semantic judgments about words• Coslett (1991)
– Reasonably good at reading irregular words, but had no understanding of them
Deep Dyslexia• Characteristics
– Particular problems in reading unfamiliar words
– An inability to read nonwords– Semantic reading errors (e.g., “ship” read as
“boat”)• Damage to the grapheme–phoneme
conversion and semantic systems• Patterson, Vargha-Khadem, and Polkey
(1989)– Studied left hemispheric removal, producing
all of these symtpoms; argued that reading is taking place in right hemisphere
• Laine et al. (2000) used MEG– Activation mainly in the left hemisphere
Parsing• Four major possibilities:
– Syntactic analysis generally precedes (and influences) semantic analysis
– Semantic analysis usually occurs prior to syntactic analysis
– Syntactic and semantic analysis occur at the same time, in parallel
– Syntax and semantics are very closely associated, and have a hand-in-glove relationship
Grammar/Syntax• Syntax – word order and combination critical
to meaning:– “He showed her the boys pants.”– “He showed her boys the pants.”
• An infinite number of sentences is possible in any language
• Sentences are nevertheless systematic and organised
• Chomsky (1957, 1959)– Rules to take account of the productivity and the
regularity of language– A grammar should be able to generate all the
permissible sentences in a given language
Syntactic Ambiguity• “They are flying planes”
– The grammatical structure is ambiguous• Global and local levels• Making use of prosodic cues
– Stress and intonation (illustrate with above example)• Allbritton, McKoon, and Ratcliff (1996)
– Doubts about the use of prosodic cues• Snedeker and Trueswell (2003)
– Listeners’ interpretation of ambiguous sentences was influenced by prosodic cues even before the start of the ambiguous phrase
Garden-Path Model• Frazier and Rayner (1982)
– Only one syntactical structure is initially considered for any sentence
– Meaning is not involved in the selection of the initial syntactical structure
– The simplest syntactical structure is chosen, making use of two general principles: minimal attachment and late closure
– According to the principle of minimal attachment, the grammatical structure producing the fewest nodes is preferred
– The principle of late closure is that new words encountered in a sentence are attached to the current phrase or clause if grammatically permissible
Evidence for the Garden-Path Model
“Put the apple on the towel in the box”
Based on data in Spivey et al. (2002).
Incorrect object: towel on its own
Disambiguating context: presenting an apple on a towel and another on a napkin
Constraint-based Theory• MacDonald et al. (1994) – all relevant information/constraints
are available – various possibilities influence comprehension to the extent they are activated– Grammatical knowledge constrains possible sentence interpretations– The various forms of information associated with any given word are
typically not independent of each other– A word may be less ambiguous in some ways than in others (e.g.,
ambiguous for tense but not for grammatical category)– The various interpretations permissible according to grammatical rules
generally differ considerably in frequency and probability on the basis of past experience
– As the woman edited the magazine amused all the reporters.– As the woman sailed the magazine amused all the reporters.
Unrestricted Race Model (combines features of GP and CB theories)
• Van Gompel, Pickering, and Traxler (2000) – combines aspects of GP and UR models– All sources of information are used to identify a
syntactic structure, as is assumed by constraint-based models
– All other possible syntactic structures are ignored unless the favoured syntactic structure is disconfirmed by subsequent information
– If the initially chosen syntactic structure has to be discarded, there is an extensive process of re-analysis before a different syntactic structure is chosen
Evidence for the Unrestricted Race Model
• Data from van Gompel et al. (2001).
Ambig: The burglar stabbed only the guy with the dagger during the night.
Verb-phrase: The burglar stabbed only the dog with the dagger during the night.
Noun-phrase: The burglar stabbed only the dog with the collar during the night.
GP: 2>3
UR: 2=3>1
Inference Drawing• Rumelhart and Ortony (1977)
1) Mary heard the ice-cream truck coming2) She remembered the pocket money3) She rushed into the house
WHAT’S HAPPENING HERE?
• Logical inferences– Depend on the meaning of the words
• Bridging inferences– Establish coherence between the current part of the
text and the preceding text• Elaborative inferences
– Serve to embellish or add details to the text
Drawing Inferences in Language Comprehension• “She took out an apple and ate it.”• Anaphora: “Bob told Bill about his
serious illness”– Bridging inference: “his” refers to
“Bob”• depends on distance between Bob and
“his” (probably not)• depends on “Bob” as topic of discourse
• Three models:– constructivist: full mental model formed– minimalist: only limited, constrained, inferences are
formed (automatic vs. strategic distinction)– search-after-meaning: meaning constructed ‘after
the fact’ in accordance to goals
• The types of inferences normally drawn, together with the predictions from the S-A-M and minimalist perspectives. Adapted from Graesser et al. (1994).
Speech/Language Production I
• Common Features of Models– extensive pre-planning– distinct stages of processing– general (intended meaning)-to-
specific (utterance) organization– most models use of speech errors as
data
Semantic substitution (“tennis bat”), blending (“sky is shining”), word-exchange errors (“let the bag out of the cat”)
Morpheme exchange errors (“trunked two packs”), spoonerisms (“hissed my mystery lectures”) within same clause
Bock & Levelt (1984)
ERRORS
Selection of word concepts, grammatical construction
Ordering parts of sentence, adding inflection
Phonological and prosodic elements worked out
Intended meaning
Phonological
Dysgraphia
Deep
Dysgraphia
Language Disorders
Types of Disorders
• Aphasia: acquired disorder of language due to brain damage
• Dysarthria: disorder of motor apparatus of speech
• Developmental language disturbances• Associated disorders
– Alexia– Apraxia– Agraphia
Major Historical Landmarks
• Broca (1861): Leborgne: loss of speech fluency with good comprehension
• Wernicke (1874): Patient with fluent speech but poor comprehension
• Lichtheim (1885): classic description of aphasic syndromes
C
M A
Lichtheim’s Model
Arcuate fasciculus
Syndrome Symptom Deficit Lesion
Broca’s Aphasia speech production;
sparse, halting speech, missing function words,
bound morphemes
Impaired speech planning and production
Posterior aspects of 3rd frontal convolution
Wernicke’s Aphasia
Auditory comprehension, fluent speech, paraphasia, poor repetion and naming
Impaired representation of sound structure of words
Posterior half of the first temporal gyrus
Pure motor speech disorder
Disturbance of articulation, apraxia of
speech, dysarthria, aphemia
Disturbance of articulation Outflow from motor cortex
Pure Word Deafness
Disturbance of spoken word comprehension,
repetition also impaired
Failure to access spoken words
Input tracks from auditory cortex to Wernicke’s area
Transcortical Motor Aphasia
Disturbed spontaneous speech similar to BA; relatively preserved
repetition, comprehension
Disconnection between conceptual word/sentence representations and motor
speech production
Deep white matter tracks connecting BA to parietal
lobe
Transcortical Sensory Aphasia
Disturbance in single word comprehension with
relatively intact repetition
Disturbed activation of word meanings despite normal recognition of
auditorily presented words
White matter tracks connecting parietal and
temporal lobe
Conduction Aphasia
Disturbance of repetition and spontaneous speech,
phonemic paraphasia
Disconnetion between sound patterns and speech production
mechanisms
Arcuate fasciculus; connection between BA
and WA
Contemporary anologues of Lichtheim’s (1885) Aphasic Syndromes
Additional Aphasia Syndromes
Syndrome Symptom Deficit Lesion
Anomic Aphasia single-word production,
marked for common nouns; repetition and comprehension intact
Impaired storage or access to lexical entries
Inferior parietal lobe or connections within
perisylvian language areas
Global Aphasia Performance in all language functions
Disruption of all/most language components
Multiple perisylvian language components
Isolation of the language zone
Spontaneous speech, comprehension, some
preservation of repetition; echolalia
common
Disconnection between concepts and both
representations of word sounds and speech
production
Cortex outside perisylvian association
cortex
Broca’s Aphasia
• Telegraphic, effortful speech• Agrammatism• Some degree of comprehension
deficit• Writing and reading deficits• Repetition abnormal – drops
function words• Buccofacial apraxia, right
hemiparesis
M.E. Cinderella ... poor ... um 'dopted her ... scrubbed floor, um, tidy ... poor, um ... 'dopted ... Si-sisters and mother ... ball. Ball, prince um, shoe ...
Examiner. Keep going.M.E. Scrubbed and uh washed and un...tidy, uh, sisters and
mother, prince, no, prince, yes. Cinderella hooked prince. (Laughs.) Um, um, shoes, um, twelve o'clock ball,
finished.Examiner. So what happened in the end?M.E. Married.Examiner. How does he find her?M.E. Um, Prince, um, happen to, um ... Prince, and Cinderalla
meet, um met um met.Examiner. What happened at the ball? They didn't get married at the
ball.M.E. No, um, no ... I don't know. Shoe, um found shoe ...
Wernicke’s Aphasia
• Fluent, nonsensical speech• Impaired comprehension• Grammar better preserved than in
BA• Reading impairment often present• May be aware or unaware of deficit• Finger agnosia, acalculia, alexia
without agraphia
C.B. Uh, well this is the ... the /dødøü/ of this. This and this and this and this. These things going in there like that. This is /sen/ things here. This one here, these two things here. And the other one here, back in this one, this one /gø/ look at this one.Examiner. Yeah, what's happening there?C.B. I can't tell you what that is, but I know what it is, but I don't now where it is. But I don't know what's under. I know it's you couldn't say it's ... I couldn't say what it is. I couldn't say what that is. This shu-- that should be right in here. That's very bad in there. Anyway, this one here, and that, and that's it. This is the getting in here and that's the getting around here, and that, and that's it. This is getting in here and that's the getting around here, this one and one with this one. And this one, and that's it, isn't it? I don't know what else you'd want.
Wernicke description of “Cookie Theft Picture”
Conduction Aphasia
• Fluent language• Naming and repetition impaired• May be able to correct speech off-
line• Hesitations and word-finding
pauses• May have good reading skills
Global Aphasia
• Deficits in repetition, naming, fluency and comprehension
• Gradations of severity exist• May communicate prosodically• Involve (typically) large lesions• Outcome poorest; anomic
Transcortical Aphasias
Transcortical Motor• Good repetition• Impairment in producing
spontaneous speech• Good comprehension• Poor naming
Transcortical Sensory• Good repetition• Fluent speech• Impaired comprehension• Poor naming• Semantic associations poor
Fundamental Lessons
• Language processors are localized• Different language symptoms can
be due to an underlying deficit in a single language processor
• Language processors are regionally associated with different parts of the brain in proximity to sensory or motor functions
What Language Disorders Reveal about Underlying Processes
• Pure Word Deafness: selective processing of speech sounds implies a specific speech-relevant phonological processor
• Transcortical Sensory Aphasia: repetition is spared relative to comprehension; selective loss of word meaning; some cases suggest disproportionate loss of one or more categories
What Language Disorders Reveal about Underlying Processes
• Aphasic errors in word production: reveal complex nature of lexical access– Phonological vs. semantic errors: independent vs.
interactive relationship?– Grammatical class: nouns vs. verbs (category
specificity)• Broca’s aphasia: syntax comprehension and production
– Central syntactic deficit; loss of grammatic knowledge
– Problems in “closed-class” vocabulary (preposition, tense markers)
– Limited capacity account– Mapping account (inability to map from parsing to
thematic roles)• Jargon Aphasia: can construct gramatically “better”
sentences than agrammatics, but can’t find words, producing neologisms; reinforces distinction between content and grammatical struture
Prosody
• Linguistic vs. nonlinguistic prosody• Evidence for hemispheric
differences• Clinical syndromes
– Disturbances of comprehension• Auditory affective agnosia• Phonagnosia
– Disturbances of prosodic output• Aprosodias
Ross & Monnot (2007) Brain and Language
Spontaneous Prosody
Good
Poor
Ross & Monnot (2007) Brain and Language
Semantic System
• System for storing meaning• Meaning stored separately from form• Models of representation in semantics
– Feature-based models (see categorization)– Nondecompositional meaning (lexicons)
• Modality-specific (fractionated) semantic deficits– Modality-specific deficts (e.g., optic aphasia)
Category-specific: e.g. living things, fruits
Two Example Models of Semantic Organization
One Semantic System
Multiple Semantic Systems