word recognition in normal reading sara c. sereno collaborators: ras/pgs: paddy...
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Word recognitionin normal reading
Sara C. Sereno
Collaborators: RAs/PGs:
Paddy O’Donnell Sébastien Miellet
Hartmut Leuthold Graham Scott
Christopher Hand
Word Recognition
• What factors affect word recognition?
• How can word recognition processes be accurately measured?
• How can effects be interpreted?
• Orthography of language– English vs. Hebrew or Japanese
• Intraword (sublexical) variables– word-initial bi/tri-grams clown vs. dwarf– spelling-to-sound regularity hint vs. pint– neighborhood consistency made vs.
gave– morphemes
• prefix vs. pseudo-prefix remind vs. relish• compound vs. pseudo-compound cowboy vs. carpet
What factors affect word recognition?
What factors affect word recognition?
• Word (lexical) variables– word length duke vs. fisherman– word frequency student vs. steward– AoA rabbit vs. violin– expert vocabulary voxel– syntactic class open/closed-class; A,N,V– ambiguity bank (“money” “river”)– concreteness/imageability tree vs. idea– animacy dog vs. cup– affective tone love vs. farm vs. fire
What factors affect word recognition?
• Extraword (supralexical) variables– Contextual predictability
Neutral He bought a large plant for his garden.
Biasing Terry went to the new gardening centre. He bought a large plant for his garden.
– Syntactic complexity
Trans. Mary took the book
VERB Mary knew the book
Intrans. Mary hoped the book
on the table.was good.
on the table.was good.
on the table.was good.
• Extraword (supralexical) variables– Discourse factors
Focus The dog chased the cat today.
The cat was chased by the dog today.
What the dog chased was the cat today.
It was the cat that was chased by the dog today.
Elaborative inferences & anaphora
What factors affect word recognition?
… The mugger her with his weaponweapon…
He threw the knife into the bushes and ran away.
stabbedassaulted
What factors affect word recognition?
• Language skill– beginning (novice) vs. skilled (expert) readers– normal vs. dyslexic vs. neuropsychological patient
How can word recognition processesbe accurately measured?
Measure Task Time Res.“electrical” imaging single word presentation ~80 – 500 ms (EEG, MEG) word-by-word reading (P1,N1,EPN,N400)
Eye movements in fixation time, location & ~250 ms normal reading sequence of EM’s
RT naming, lexical decision ~500 – 800 ms categorization tasks;
± priming, masking, lateralized presentation
“blood flow” imaging single word presentation seconds (PET, fMRI)
Thisisawordbywordpresentationofasentenceatafastreading-likerate.
Word-by-word reading: 200 ms per word
Thisisawordbywordpresentationofasentenceataslowratetypically usedinERPstudies.
Word-by-word reading: 600 ms per word
Normal Reading
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.
*
This is an approximation of normal reading
in real time.*
This is an approximation of normal reading
in real time.*
This is an approximation of normal reading
in real time.*
The importance of making eye movements in normal reading
Cond1 There was a box of…
Cond2 There was an enormous box of…
Cond1 She saw a cat in the…
Cond2 She saw a cup in the…
Perception of text influences how EMs made.
AND
Location/duration of EMs affect perception.
(1) Pick factors: stimulus quality, frequency, predictability
• Additive factors
How can effects be interpreted?
StimulusQuality
Context
Frequency
RTLo freq
Hi freq
+ – stim qual
RT
+ – context
– stim
+ stim
RT
+ – context
Lo freq
Hi freq
(3) Additive sequential Interactive overlapping
(2) Independently manipulate 2 factors at once:
oculomotor-related factorslaunch distance to wordlocation of fixation within wordnumber of fixations on wordword lengthword frequencycontextual predictability
language-related factors
How can effects be interpreted?• Modelling
(1) Pick factors:
oculomotor-related factorslaunch distance to wordlocation of fixation within wordnumber of fixations on wordword lengthword frequencycontextual predictability
language-related factors
How can effects be interpreted?• Modelling
(1) Pick factors:
(2) Perform repeated measures multiple regression analysis to determine which factors account for most variance.
Factors Measures Approachorthographybi-/tri-gramsregularityneighborhoodmorphologylengthfrequencyjargonword classambiguityimagabilityanimacyemotionalitypredictabilitysyntactic prefs.focusinferenceanaphoraskill
ERPs+
word-by-word(slow) presentation
Eye movements +
normal reading
EM-ERPco-registration?
Additive factors
Repeated measuresmultiple regression
Distributed hierarchical visual processing in primateslexical humans
higher-levelsemantics
syntax
meanings
word forms
letters
features
Conclusion
Precisely delineating the time course of different components of word recognition allows us to:
– determine when top-down effects modulate bottom-up processes;
– inform neuroimaging localisation studies in order to construct a temporally realistic neural circuitry of normal reading.
Measurement
EMs = best on-line measure of visual word recognition in the context of normal reading
ERPs = best real-time measure of brain activity associated with the perceptual and cognitive processing of words
(Sereno & Rayner, Trends in Cognitive Sciences, 2003)
(Sereno & Rayner, Trends in Cognitive Sciences, 2003)
Sereno, Rayner, & Posner (1998). NeuroReport.Sereno, Brewer, & O’Donnell (2003). Psych. Sci.