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Mental Lexicon. All of your knowledge about words and you know a lot of words! Average college-educated adult Speaking vocabulary = 75,000 - 100,000 words Recognition vocabulary is substantially larger You're not equally likely to use all of those words

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mental lexicon
Mental Lexicon
  • All of your knowledge about words
    • and you know a lot of words!
  • Average college-educated adult
    • Speaking vocabulary = 75,000 - 100,000 words
    • Recognition vocabulary is substantially larger
  • You're not equally likely to use all of those words
    • The 50 most common words make up
      • ~60% of the words we speak
      • ~45% of the words we write
    • On average, you only say 10-15 words before repeating one

Psyc / Ling / Comm 525 Fall 10

10 most frequent english words counts out of 1 000 000 words
10 Most Frequent English Words(counts out of ~1,000,000 words)

Notice that most are function words rather than content words

Psyc / Ling / Comm 525 Fall 10

writing systems
Writing Systems
  • Two basic types of writing systems
    • Ones that indicate pronunciation
    • Ones that do so less
  • Systems that do represent pronunciation:
    • Alphabets- One character supposed to represent one “sound”
      • ALL modern alphabets are derived from Phoenician
    • Syllabaries- One character represents a whole syllable
      • In most, 2 syllables that share a sound don’t look anything alike
        • Japanese hiragana:か= /ka/ vs き=/ki/ vs く=/ku/
        • But, Korean hangul has C & V characters within syllable: 수잔 = /suzn/?
  • Systems that represent pronunciation less directly:
    • Ideograms (pictograms) - One character represents a meaning
      • Words with similar meanings usually share characters, even if pronunciation is completely different
      • But often words that share a syllable that has different meanings in each word also share a character

Psyc / Ling / Comm 525 Fall 10

word boundaries
Word Boundaries
  • Most (all?) languages using Roman alphabet put spaces between words
  • But some other writing systems do not (e.g. Chinese, Japanese)
    • - Sometimes ambiguous where word boundaries are (just as in speech)

Psyc / Ling / Comm 525 Fall 10

bottom up and top down processing in reading
Bottom-up and Top-down Processingin Reading
  • Some examples:
    • Detecting particular letters is less accurate in highly familiar words
    • Proofreading is harder the more familiar the text

Psyc / Ling / Comm 525 Fall 10

slide8

Does this remind you of

anything about auditory

word recognition ?

Psyc / Ling / Comm 525 Fall 10

bottom up and top down processing in reading9
Bottom-up and Top-down Processingin Reading
  • Some examples:
    • Detecting particular letters is less accurate in highly familiar words
    • Proofreading is harder the more familiar the text
  • - ...
  • Race Models of word recognition
    • Top-down and bottom-up processes go on in parallel
    • Racing with each other
    • Whichever "finishes" first wins the race
      • i.e. determines how you identify the word
    • If bottom-up processing is hard because input is noisy, top-down wins
    • If little help from context, bottom-up wins
  • Decision Criterion = Finish line in race
    • How sure must you be that the input is a word before saying so?

Psyc / Ling / Comm 525 Fall 10

disorders of reading
Disorders of Reading
  • Patterns of Acquired Dyslexia have influenced theories and models of normal reading
    • More than observations of any other kind of language deficit have influenced models of other aspects of normal language processing

Psyc / Ling / Comm 525 Fall 10

surface dyslexia tends to occur in fluent aphasics with posterior brain damage
Surface Dyslexia(tends to occur in fluent aphasics with posterior brain damage)
  • Read regularly spelled words aloud ok
  • Read nonwords aloud ok
  • Tend to mispronounce irregularly spelled words
    • They regularize them
      • island > /Izlǽnd/
      • pint > /pInt/
    • So, they seem to
      • construct pronunciations via direct letter-to-sound mappings
      • without retrieving knowledge about particular words' pronunciations

Psyc / Ling / Comm 525 Fall 10

slide12
Phonological Dyslexia(often no other aphasia)(most similar of the acquired dyslexias to developmental dyslexias)
  • Read highly familiar words aloud ok, regardless of spelling regularity
  • Trouble reading both less familiar words and non-words aloud
    • Tend to pronounce them as similar-looking familiar words
      • i.e., they lexicalize them
      • forb > fork
      • moth > mother
      • border > bread
    • If the word they come up with happens to have an irregular spelling for its pronunciation, they pronounce it in the correct irregular way
    • So, they seem to
      • get into the neighborhood of words that look like what they see
      • & retrieve the pronunciation of one of the more familiar words in that neighborhood

Psyc / Ling / Comm 525 Fall 10

deep dyslexia tends to occur in non fluent aphasics with anterior brain damage
Deep Dyslexia(tends to occur in non-fluent aphasics with anterior brain damage)
  • Read content words aloud a lot better than function words
  • Within content words, better on concrete, imageable ones
  • Often can't read non-words at all, or may lexicalize them
  • Errors sometimes semantically related, with no sound or spelling similarity
    • ape > monkey
    • forest > trees
  • Errors sometimes visually related instead, or mixed visual and semantic
    • scandal > sandals
    • orchestra > sympathy
  • So, they seem to (sometimes)
    • get into the neighborhood of words with meanings like what they see
    • & then retrieve the pronunciation of another word in that neighborhood

Psyc / Ling / Comm 525 Fall 10

modular vs interactive processing systems
ModularvsInteractive Processing Systems
  • It’s obvious that bothbottom-up and top-down processes contribute to the recognition of letters & sounds & words
  • But how does top-down processing work?
    • Interactive account:
      • Context & knowledge guide actual perception of input

vs

    • Modular account (= post-perceptual, autonomous):
      • Context & knowledge influence choices among alternative candidates proposed by perceptual processes

Psyc / Ling / Comm 525 Fall 10

slide20

Localist

Psyc / Ling / Comm 525 Fall 10

slide21

Localist

Psyc / Ling / Comm 525 Fall 10

slide22

Localist

Psyc / Ling / Comm 525 Fall 10

modular account of phoneme restoration
Modular Account of Phoneme Restoration
  • The connectionist account is interactive
  • In contrast, a modular account says:
    • No top-down feedback from words to sounds
    • Instead, system guesses there must have beens because that's what would make sense
    • An unconscious decision process

Psyc / Ling / Comm 525 Fall 10

slide24
Each of the next 3 slides has a list of letter strings
  • Your task is to read through them as quickly as you can and count how many of them are words
  • Raise your hand as soon as you’re done

Psyc / Ling / Comm 525 Fall 10

slide25
zyndc

cnccl

apple

frgtd

wrpts

brat

nxprd

must

lbdry

other

nrgln

sfbdl

war

cloth

dtrnp

library

stwsn

mplfs

Psyc / Ling / Comm 525 Fall 10

slide26
bant

anger

fold

bagin

pretser

mash

kalt

magic

lomp

sinos

arid

hink

radle

track

rean

supper

weth

amol

Psyc / Ling / Comm 525 Fall 10

slide27
brane

leev

want

damp

stane

mair

quick

lowd

heeter

power

wim

pryse

muther

prefer

koller

heaven

much

prufe

Psyc / Ling / Comm 525 Fall 10

slide28
Why were you slower on the second list than on the first, and even slower on the third list, even though there were 7 words in each list?
    • Because the nonwords (NWs) grew progressively more word-like across the lists
      • In list 1, the NWs were not even pronounceable and had illegal sequences of letters
      • In list 2, the NWs were pronounceable and followed legal English spelling patterns
      • In list 3, NWs all had the same pronunciation as a real word

= pseudohomophones

Psyc / Ling / Comm 525 Fall 10

tasks strategies
Tasks & Strategies
  • You adopted different decision criteria in the 3 different lists
    • about how fully to process the letter strings before moving on to the next one
  • So, sometimes the "distractors/fillers" in an experiment can matter a lot!
    • Influence task-specific response strategies people can adopt
    • Crucial to think very carefully about how participants could be doing the tasks we give them
    • But also important to realize people’s intuitions about how they’re doing something are often not reliable

Psyc / Ling / Comm 525 Fall 10

slide31
When you encounter a new word you don’t know, you can tell a lot about it from:
    • its position in the sentence relative to other words you do know

= Syntax

    • its prefixes and suffixes

= Morphology

Psyc / Ling / Comm 525 Fall 10

the jabberwocky lewis carroll
The JabberwockyLewis Carroll

One two! One two! And through and through

The vorpalbladewent snicker-snack!

He left it dead, and with its head

He wentgalumphing back.

"And hast thou slain the Jabberwock?

Come to my arms, my beamishboy!

Oh frabjousday! Callooh! Callay!"

He chortled in his joy.

'Twas brillig, and the slithytoves

Did gyre and gimble in the wabe:

All mimsywere the borogoves,

And the momerathsoutgrabe.

Adjectives, Nouns, Verbs

= Parts of speech

= Syntactic categories

'Twas brillig, and the slithytoves

Did gyre and gimble in the wabe:

All mimsywere the borogoves,

And the momerathsoutgrabe.

"Beware the Jabberwock, my son!

The jaws that bite, the claws that catch!

Beware the Jubjub bird, and shun

The frumiousBandersnatch!“

He took his vorpalsword in hand:

Longtime the manxomefoe he sought --

So rested he by the Tumtum tree,

And stood a while in thought.

And, as in uffishthought he stood,

The Jabberwock, with eyes of flame,

Came whiffling through the tulgeywood,

And burbled as it came!

Psyc / Ling / Comm 525 Fall 10

morphology
Morphology
  • Many words have internal structure
    • friend > friendly > unfriendly > unfriendliest
  • Morpheme = smallest meaningful unit in language
    • friend = 1 morpheme
    • unfriendliest = 4 morphemes (end is not a morpheme in friend)
  • Affixes = prefixes, suffixes, & infixes
  • Free morphemes (friend, the) vs

Bound morphemes (un-, -ly, -est)

  • Lexical (= Content)morphemes(friend) vs

Grammatical (= Function) morphemes (the, un-, -ly, -est)

  • Allomorphs = different versions of same morpheme
    • (Remember allophones?)
    • English plural = /s/, /z/, /Iz/, /In/, ...
    • English indefinite article = a, an

Psyc / Ling / Comm 525 Fall 10

slide35
Languages vary from having:
    • Many short simple words and using more of them
      • (e.g. Chinese = isolating)
    • To having mostly long complex words and using few of them
      • (e.g. Turkish, Hungarian = agglutinative)
  • English is somewhere in between
  • Term Morphosyntax reflects the fact that the same kinds of relationships are coded morphologically in some languages & syntactically in others

Psyc / Ling / Comm 525 Fall 10

does morphological structure affect reading
Does Morphological StructureAffect Reading?
  • People do seem to decompose complex words during reading
    • Priming from regularly inflected morphological relatives can be equivalent to repetition priming
      • e.g., believes primes believe just as much as believe primes itself
    • But priming from irregularly inflected or derivational relatives is smaller
      • e.g., believer doesn’t prime believe as much as believe primes itself, nor does went prime go as much as go primes itself or as much as repeated primes repeat
  • Even when what looks like a morpheme really isn’t
    • e.g., beak- and -er in beaker
    • Get effects of frequencies of apparent subcomponents
      • The frequency of the word beak (meaning a bird’s beak) influences response time to beaker even though its meaning is not a component of the meaning of beaker

Psyc / Ling / Comm 525 Fall 10

eye movements
Eye Movements
  • Two types of eye movements
    • Smooth pursuit
      • Long smooth movements
      • Can only do this if eyes are following something
    • Saccades
      • Short jumps
      • Most eye movements
  • When eye is not moving = fixations
  • Reading consists of saccades and fixations
  • Backward saccades = regressions

Psyc / Ling / Comm 525 Fall 10

eyetracking dual purkinje tracker
Eyetracking (Dual Purkinje Tracker)
  • - Dim infrared light shines on eye
  • - Reflections bounce back from different layers in eye
  • Relative positions of different reflections show where eye is pointing
  • Some other kinds of eyetrackers work in different ways

Psyc / Ling / Comm 525 Fall 10

span of fixation
Span of Fixation
  • How much can you see during a single fixation?
  • -
  • It depends on:
    • your visual acuity
    • your reading skill level
    • how hard what you’re reading is, overall
    • how familiar the current and preceding and next words are
    • how predictable the current and preceding and next words are
    • ...
    • how much of current word you could see on previous fixation

Psyc / Ling / Comm 525 Fall 10

what techniques could be used to answer this question
What techniques could be used to answer this question?
  • Eyetracking
    • Contingent display changes (McConkie & Rayner)
      • Moving window = 1 special type
    • Works because you’re functionally blind during saccades
      • so you don’t see the change itself happen
    • Need eyetracker & computer fast enough to complete display changes before saccade ends
      • Average saccade only lasts 10-20 msec

Psyc / Ling / Comm 525 Fall 10

slide45
So, how far ahead does the eye see?
    • Get different answers when
      • Ask people what they consciously notice

vs

      • See what affects their eye movement patterns

Psyc / Ling / Comm 525 Fall 10

contingent display change
Contingent Display Change
  • Idea:
    • If something peripheral changes just before the eye reaches it
      • during a saccade, so don’t see change itself happening
    • If the eye stays on the changed thing longer than when that’s what was there all along
    • what was originally there must have been "seen" peripherally
  • Answer to the question:
    • You can sometimes get wordshape and initial letter info as far ahead as 10-14 characters
    • But you have to get as close as 6 characters before you detect the "wordness" of the next unit

Psyc / Ling / Comm 525 Fall 10

semantic priming phenomenon tool
Semantic Priming(Phenomenon & Tool)

... ...

arm arm

kitchen kitchen

tree tree

Related prime >doctoractor < Unrelated prime

nurse<Target> nurse

floor floor

... ...

  • In a priming experiment:
    • Some people see nurse immediately after doctor in a list of words

= Related condition

    • Others see nurse after an unrelated word like actor

= Unrelated condition

- Notice that target word is identical across conditions, so important word properties like frequency & length are perfectly controlled

    • People respond faster, on average, in Related condition

= Priming (= facilitation)

Psyc / Ling / Comm 525 Fall 10