Reading
• Model of word recognition
• Two theories
– indirect access
– direct access
• Individual differences
• Comprehension
– two measures
– effects of prior knowledge
– organization of the text
• global coherence
• local coherence
– Kintsch’s model of comprehension and “readablity”
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Word Recognition
• The relationship between speech and reading
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silent letters
introspective connection
acoustic recoding
what is the role of acoustic recoding in reading?
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Model of Reading
sentence
Visual encoding
Speech recoding
Semantic
Lexical access
LTM
Working memory
LTM
Tentative propositional structure
Store propositional structure
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Two theories
• Indirect access
– must go through speech (acoustic recoding) to get to meaning
• Direct access
– skilled readers get immediate visual access to meaning
– faster, no recoding
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Evidence For Indirect Access
• EMG recordings of vocal apparatus while people read
– people moving their lips while reading
• Lexical decision task (is this a word)
– phonemic similarity increases lexical RT
– e.g. it takes longer to say “NO” to “brane” than to “melp” because “brane” is
acoustically equal to “brain”
– e.g. faster RT to “set - wet” (rhyming pair) than to “few -sew” (graphemically
similar but pronounced differently
• Errors during letter search and proof reading are
influenced by phonemic factors
– the silent versus pronounced “e”s
– in proof reading “borst” for “burst” is easy, but “hurd” for “heard” is hard
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Evidence For Indirect Access
• People often sound-out words when material is difficult
– when people are prevented from making lip movements they may have more
trouble reading difficult material
• Mistakes on categorizing homonyms
– “rows” as a flower
– “which” as a character in a Halloween story
• Phonological readiness for reading
– e.g. Kyle’s difficulty with phonological understanding
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Evidence for Direct Access
• Profoundly deaf can read
– but have trouble learning and never get as good as hearing readers
• Profoundly deaf
– not make same letter search errors
• equal number of errors on silent and pronounced letters
– not have same proofreading errors
• Acquired phonemic dyslexia
– can repeat words they have heard but cannot read out loud
– can not sound-out phonemes
– can get direct access to meaning but may be slightly “off”, e.g. read “dream”
as “sleep”
– also not have same types of proofreading errors as normal readers
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Evidence for Direct Access
• Semantic decision task
– decisions about individual words not affected by phonemic factors
• e.g. vary number of syllables - “clerk” versus “secretary”, same RT when
asked if an accupation
• Use of homonyms
– same sounds that lead to different meanings
• In reading aloud “mown- down” and “horse - worse” are
problems because of pronunciation, but not a problem
in silent reading
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Conclusion
• Dual encoding
– may speech recode
– speech recoding may be necessary for learning
– skilled readers have direct access
• like the horse race model
– maybe direct visual access only for overlearned or automatized words
• Why speech recode?
– Facilitate working memory (ease storage)
– especially for:
• difficult passages
• when memory will be tested
• under stress
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Individual Differences
• What differentiates good, average, and poor readers?
• Many different theories
• Three processing differences
– use of phonemic code
– capacity of working memory
– speed of letter encoding
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Three processing differences
• Use of phonemic code
– good readers have greater reliance on phonemic code
• for second graders good readers how more interference from the
rhyming words (set-wet, few-sew) than poor readers
• general use of phonemic code first appears around age 5
– “reading readiness”
• Capacity of working memory
– reading span task
• read aloud a series of sentences and then recall the last word of each
sentence
• measures how many sentences can be held in STM
• normal span is 2 -5 sentences
• correlated with reading comprehension scores and SATs
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Three processing differences
• Capacity continued
– some forms of dyslexia are based on STM problems
– What causes the differences?
• More storage
• faster processing
• efficiency
• can this be learned
• Speed of letter encoding
– Posner letter matching task
• not faster at perceptual match
• faster at same name and homophone task
– not a perceptual processing difference, but a difference in access to
phonetics and LTM
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Reading Comprehension
• Study how individual differences in prior knowledge
and information processing characteristics interact with
the organization of ideas in the text
• Two measures of comprehension
– subjective - rate ease of understanding
– objective - number of ideas recalled
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Prior Knowledge
• Context
– picture as context, measure number of ideas recalled
• no picture average 3.6 ideas recalled
• picture before text average 8.0 ideas recalled
• picture after text recalled 3.6 ideas
– context must come before the text
• not just provide retrieval cues
• provide organization
– titles also act as context (familiar activities)
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Prior Knowledge
• Can lead to false recall
– general passage about a man
– half subjects are told the man is Gerald Martin and half are told it is about
Adolf Hitler
• the “Hitler” subjects primarily recalled information consistent with their
prior knowledge of Hitler
• after one week could not distinguish past knowledge of Hitler from
information provided in the text
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Prior Knowledge
• Perspective influences recall
– Anderson and Pritchert ‘s study of a long story about two boys who play
hookey and stay at one boy’s wealthy parents’ house.
• lots of details about their valuable possessions
• also details about the house being old with a leaky roof, damp basement
and other problems
– Subjects are told to recall ALL information, but
• group one is told to take the perspective of a burglar
• group two is told to take the perspective of a home buyer
– groups recall information relevant to their perspective, then
• half are given a new perspective
• half are told to try again with same perspective
– groups that switch perspective recall more
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Prior Knowledge
• Perspective continued
– three reasons why a change in perspective may increase recall
• guess ideas consistent with new perspective
• not try to recall irrelevant info
• perspective provides a plan for searching memory!!!!!!!!!!
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Organization of the text
• Global coherence
– main events, characters and goals
– depends upon type of text
• story grammars (goals, conflict, and resolution)
• cultural differences in narratives (organization and flow)
• text books and how to set up global coherence
– history
– subfields
– major problems (questions)
• Local coherence
– integration of immediate ideas
– causal connections
– anaphoric reference
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Kintsch’s Model of Comprehension
• Simplified model
– major point is that incoming information can be understood more easily if it
can be integrated with information the reader has already encountered
– easiest is when new information fits with information currently in working
memory
– if not currently in working memory must do a “reinstatement search”
• look for related propositions in LTM and transfer them to working
memory
– hardest is when no relevant information is found during “reinstatement
search”
• must start a new association network
– less well recalled
– not well integrated
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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Kintsch’s Readability formula
• Formula
– readability is predicted by the number of recalled propositions divided by the
reading time
– this correlated best with
• word frequency
• number of required reinstatement searches
• number of inferences required
Sensation and Perception - reading.ppt © 2001 Laura Snodgrass, Ph.D.
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