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. 1 Word Recognition • The relationship between speech and reading – – – – 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. 2 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. 3 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. 4 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. 5 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. 6 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. 7 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. 8 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. 9 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. 10 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. 11 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. 12 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. 13 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. 14 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. 15 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. 16 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. 17 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. 18 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. 19 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. 20