Psycholinguistics : Consequences of reading Flashcards
Learning to read
Map written symbol onto laguage units that are phonems in latin alphabet (but could be words for logographic [Chinese] or syllables [Japanese])
>> VERBAL SYSTEM
Use the visual modality to access cerebral speaking system.
>> Via VWFA
Writting system / orthography
WS : differ according to the level of spoken language wich represented in written language
Orthography : refers to the conventions used in a specific language
Othographies
transparent / opaque
Transparent
simple grapheme to phoneme mapping (vice versa)
> italian, german
Opaque
Several graphemes for one phoneme (vice versa)
> English
French : intermediate position
Graph to phon (reading) : 88%
Phon to graph (spelling) : 50 %
Twice as slow for non shallow orthography
Difficiulties of learning to read
Into which spoken language unit should written language be analysed (word, syllables, phonemes)
Integrate specific rules of spelling :
french /wa/ <>“oi”
“i” in english : several prononciations (bird, flight, hit)
Becoming a fluent reader requires
To understand that speech is made of phonemsù
> Phonological awereness
To understand that letters/letters groups correspond to these phonemes
> alphabetical principle
To learn the grapheme-phoneme correspondances
To make word processing automatic
Phonological awareness
Ability to manipulate intentionnally phonological units (non significant)
Pay attention to form, not meaning
Longitudinal studies (Lecoq, 91)
56% de la variance fin CP est expliquée par un score composite de conscience phonologique
MOST IMPORTANT PRECURSOR OF READING
especialy phonemic consciousness task
Alphabetic system makes the conscious manipulation on phonemes crucial (causal link : Bryant 83)
Brain aspects
VISION
Occipital cortex
VWFA (N170)
Visiual Word form area (fusiform gyrus)
REPRESENTATIONS PHONOLOGIQUES
Planum temporale
The Visiual Word Form Area
Vision involved in reading but no brain area devoted to reading
Part of the visual area which is responding more strongly to written language
Occipito temporal cortex LEFT
Responds to word and pronuncable pseudowords
reproductble in all individiuals
Accross language
A strong responsivness after some months of reading
Recycling hypothesis
Dehaene
Neurons initialy devoted to to face processing are progressivly specialized into ortography processing
Literacy
Set of processes and reprensenations an individiual possesses as a direct consequence of having learned to read
Set of skills related to reading and spelling
Studies on illiterates people
Studies on illiterates people (and ex-illiterates) allows to better understand impact of reading on cognition and on brain, avoiding the issue of maturation.
> Determine what, in cognitive system results from learning
> Identify the factors which could originate severe reading disabilities such as developmental dyslexia
Dyslexia
Of the impairment of the skill X in connection to the reading failure individuals with dyslexia.
If illiterate people perform lower than literates (including ex illiterates) on the skill X, we can not conclude that a low achievement of X is a cause of dyslexia.
By contrast, if illiterates perform within a normal range on the skill X, we can exclude the hypothesis according to which the reading level determines the performance on X
Metaphonology
Conscious representatiton of phonemes
Depends on literacy - Not in general but in alphabetical system in particular
Syllables are easier to manipulate
Learning effect (feedback) \> With training, illiterates can restore this ability
Phonemes perception
96% minimal pair discrimination
Babies can discriminate stimuli that differ for only one phoneme
(succion non nutritive)
Boundaries shaped by orthography ?
> Illiterates have not really clear boundaries
Knowledge of the letter shapes the way we perceive sounds
⇒ Strong impact of an artificial ability (reading) on a natural ability (perceiving sounds)
Illusory conjunctions
Illiterates also have illusions
⇒ Their brain process speech in a normal way
Illiterates
Can’t manipulate phonemes
Have less precise phoneme bondaries
Perception is not so different
Non verbal skills
Illiterates perform lower in picture completion, block design, picture arrangement, object assembly
pas dû à la mémoire ( présentation simultanée)
Perform less for different : they decide stimuli are different when they are identical
CC : Illiterate people do process information in a specific way as compared to literate people (and ex illiterate)
Impact on cognition : visual processing
Face recognition
Face recognition
Neuronal recycling hypothesis (Dehaene 2005)
The VWFA is devoted to face recognition and becomes devoted to orthography processing (left hemisphere)
Ventura et al, 2013 - matching task (only bottom part of face)
Litterates and ex-illiterates are better to decide whether the bottom halves of faces are same or different without being disrtacted by the top part of the images.
Strongly misaligned faces were used to facilitate attention to the target part.
If the stronger congruency effect for aligned than misaligned stimuli reflects holistic processing, then illiterates rely on holistic processing more than ex-illiterates and literates
Reliance on holistic processing
Thus far results are consistent with the hypothesis that acquiring literacy enables to partly reduce reliance on holistic processing
Ventura et al 2013
Impact on cognition : visual processing
Mirror invariance
Dehaene 2010
Mirror invariance is the capacity to recognize a visual image as identical after a left–right inversion. Mirror invariance is useful in the natural world because a lateral reversal usually does not affect the identity of natural objects
However, mirror invariance is undesirable for reading.
it is necessary to discriminate mirror letters! such as ‘p’ and ‘q’, or ‘b’ and ‘d’. It has therefore been suggested that learning to read requires the ‘unlearning’ of mirror invariance
Left fusiformVWFA simultaneously shows a maximal effect (repetition suppression) of mirror priming for pictures and an absence of mirror priming for words
Japanese : facilitation <= no need to pay attention to orientation of symbols
Literate adults are slower in judging whether two images represent the same object if they are mirror images
Children writting in mirror
Decreases when learn to read (except dyslexic)
Impact on cognition : speech processing
There is accumulating evidence that orthography influences spoken language.
Metaphonological tasks (Seidenger+ 79) : rhyme judgement for spoken words better when spelling is the same (pie/rye vs pie/tie)
++ Auditory lexical decisions
++ phonological priming in spoken word recognition
Ziegler & Ferrand 98 - ERP - Lexical or post lexical (decision)?
Early inconstency 132ms ! Even prelexical
Conclusion
Beign litterate has a strong impact on our brain connectivity and cognition. The way we speak and also the way we see.
Literacy affects
> Metalinguistic tasks
> Speech processing and spoken word recognition
> Visual processing
This should be taken into consideration when assessing people who may vary in there reading skills.
Text DEHAENE
3 major brain systems in wich changes are observed
Early visual system
> early occipital ERPs
>
> faces
Ventral visual pathway
> Fusiform VFWA (N170)
Phonological coding system
Resume
Given the evidence discussed above, we
reach a conclusion that literacy affects brain
organization primarily by creating and auto-
mating an efficient interface between vision
and language. This broad change is medi-
ated by a reorganization of the left VOT (the
VWFA). Its putative afferents (the bilateral
occipital visual cortices) and its putative
efferents (the left superior temporal regions,
such as the PT for phonological analysis) are
also enhanced. Finally, an extended network
of surrounding temporal and occipito-
parietal areas is also improved, particularly
when effortful grapheme-to-phoneme
conversion is called for. Anatomically, the
physical connections among these areas —
notably, the posterior corpus callosum and
left arcuate — are changed in a detectable
manner. Functionally, these changes result in
fluid, bidirectional interactions between the
internal representations of written symbols
and spoken language.
