PSY2002 W3 Reading & Dyslexia (L) Flashcards
What is the processes that support visual word recognition (reading)?
Activation of mental representations of processes are required to read and recognize printed words
What is the Dual Route Cascaded (DRC) model of visual word recognition models reading?
Assumes that we have a lexical and non-lexical route for reading that facilitates the recognition of regular and irregular words
What is the relationship between the DRC model and Shre’s 1995 self-teaching hypothesis?
Share’s 1995 self teaching hypothesis resonates with the DRC model that assumes we have a non-lexical route to facilitate decoding when we start to read.
Does phonological deficit underpin all cases of dyslexia?
although researchers agree that for many a phonological deficit underpins dyslexia evidence of surface dyslexics suggest that some may have a deficit in orthographic learning
What tasks/methods are used to assess vissual word recognition?
Priming paradigms combined with a variety of tasks are used to assess semantic processing. Tasks such as Phoneme deletion and rapid automatic naming are used to assess visual word recognition and reading
What is reading?
Fundamental elements of communication.
Mental representation of comprehension
Written word [imput]>activate existing mental representation of written word - link to meaning > comprehension [output]
What is orthography?
Form in reading/written word comprehension
What is the logographic system?
characters represent words
What are the possible routes of reading?
Route 1: Less strong wrritten lexical: Written word input > activate letters > activate phonemes (via letters) > activate phonological form > semantics.
Route 2: Strong written lexical: Written word input > activate ltters > activate orthographic form > activate phonological form > semantics.
Rpite 3: May Bypass phonological form altogether and go straight from orthography to semantics: Written word input > activate letters > activate orthographic form > semantics.
What is the DRC: Dual Route Cascaded model of visual word recognition and reading aloud?
Coltheart, Rastle, Perry, Langdon & Ziegler, 2001
CDP + Model
1-Phonemes Nodes
1a- [semantics]: Phonological lexicon <> orthographic lexicon
1b- Grapheme nodes
2- Letter nodes <> feature detector
Triangle Model
Semantics//Orhtography//phonology
DRC Model
Phoneme system <> Phoological lexicon <> Semantic system//Orthographic lexicon <> Letter units < Visual features
Visual features > Letter Unites > Grapheme- phoneme rule system > phoneme system
What does computational modelling allows us to do?
ask very specific questions, test the results, but rarely able to model all the variables and parameters at work, not likely to get an absolute anwser but excellet to test specific questions
The model assumes that we have two route to process visual words (reading)
the lexical route activate n orthographic representation that is linked directly to meaning
What is speeling-to-sound correspondence?
The relationship between letters and sounds is referred to as Grapheme Phoneme correspondence and maybe key to understanding the problems encountered by people with dyslexia.
What are regular words?
Follow a set of rules that dictate how a grapheme should be pronounced.
MINT is regular word but PINT is irregular both words contain the grapheme ‘i’ in MINT pronunciation is regular and in PINT it is irregular
80% of English monosyllables could be pronounced using a relatively small set of rules relating graphemes to phonemes.
What is a regular pronunciation?
aligns with the graphemes most frequent pronunciation
What is transparent grapheme phoneme correspondence?
Orthographies with a lot of regular correspondences -> TRANSPARENT
DOG, PRINT, COBWEB = regular words
What is opaque grapheme phoneme correspondence?
Orthography with few regular correspondences -> OPAQUE
YACHT, KNIGHT, COLONEL = irregular words
Is english considered a transparent orthography?
no because there’s to many irregular correspondence
What is shallow orthography?
Transparent Language – Shallow orthography: The spelling of each word maps directly on to its pronunciation (e.g., Finnish or Italian)
What is Depp orthography?
Opaque Language – Deep orthography: The spelling of each word does not map directly on to its pronunciation (e.g., English)
What are some advantages of the DRC?
- Allows 2 routes for processing written word
- Accounts for Orthographic lexicon and phonological lexicon
- Accounts for processing of regular and irregular words
- Accounts for encountering new or novel words, can be processed via grapheme-phoneme correspondence.
What is the self-teaching hypothesis?
Share, 1995
- Children ‘de-code’ words using an understanding of how letters correspond to sounds
- Existing phonological representations are accessed – used to access meaning
- The phonological representation is used to develop an orthographic lexicon of whole words
- In other words they teach themselves to read.
What is the slef-teaching DRC ? - learning to read
Pritchard, Coltheart, Marinus & Castles, 2018)
The ‘non-lexical’ route is used to decode words and access an existing phonological representation.
Contextual cues are used to select the target word from a list of spoken word candidates – many spoken word candidates – select the best match from context.
Exposure to print facilitates the development of an orthographic lexicon – Lots of reading on a regular basis necessary
When we learn to read we use the non-lexical route to de-code words. Generating a phonological representation that can access the semantic system and start to build an orthographic lexicon.
Gradually building up the representations in the orthographic lexicon as we acquire more written words.
What can we bypass when we are a skilled reader?
Once we become a skilled reader we can bypass the non lexical route and access semantics directly via activation of orthographic representations in the orthographic lexicon.
A rich network of connections from print to meaning combined with automatic processes that activate meaning without requiring further processing allow skilled readers to process written words rapidly
What is the self-teaching hypothesis?
If ‘decoding’ words to access phonological representations is necessary for the development of an orthographic lexicon
Children who struggle to link graphemes with phonemes might not be able to ‘teach themselves to read’
If ‘de-coding’ words is necessary for the development of an orthographic lexicon children with dyslexia may not be able to ‘teach themselves to read’
What is dyslexia?
DSM 5
“Difficulties in accuracy or fluency of reading that are not consistent with the person’s chronological age, educational opportunities or intellectual abilities”
What is dyslexia?
British Dyslexia Association
“Dyslexia is a specific learning difficulty that mainly affects the development of literacy and language related skills. It is characterised by difficulties that may not match up to an individual’s other cognitive abilities.”
NHS “It‘s estimated that up to 1 in every 10 people in the UK has a certain degree of dyslexia”
How does Lyon et al. 2003 define dyslexia?
“difficulties with accurate and/or fluent word recognition, poor spelling and decoding abilities that are unexpected in relation to other cognitive abilities”
How does Ahmed et al. 2012 define dyslexia?
Difficulty decoding words results in an inability to sound out new words. Difficulty recognising known words that results in impoverished sight word reading
How does Snowling and colleagues define dyslexia?
problems with phonological processing in understanding how speech sounds correspond to letters.
A learning difficulty underpinned by problems with phonological processing and speech/sound-letter correspondence.
Not a visual problem as demonstrated by difficulty identifying phonemes. An interaction of gene and environment that puts some children more at risk than others
What skills are affected by dyslexia?
decoding, lexical retrieval and verbals short-term memory
What are decoding skills ?
convert graphemes into phonemes (Phoneme deletion/substitution task, Decoding pseudowords (non-words))
What is lexical retrieval ?
recognize whole words (i.e. activate representations is an orthographic lexicon. (Rapid automatic naming (RAM) tasks, word identification of regular and irregular words
What is verbal short-term memory?
retain information in short term memory (word span, digit span)
How can we test phonological awarness?
Longitudinal study, phoneme identification, say ‘speech’ without the ‘s’, say the ifrst sound in the word ‘train’. Graph shows no deficit in kindergarten, a problem appearing after 1 year of reading instruction that disappears by the end of primary school
How can we test reading impairment profiles?
Nation (2019) Learning to read longitudinal data set. Dyslexic Participants only. From a sample of 242 children 34 poor decoders. Worse performance on measures of phonological awareness at age 7 compared to age 5.
How is automatic word processing tested?
RAN Task: Name images, letters or digits as rapidly as possible
Graph shows both dyslexic and weak readers are slower to name objects than the control group. Identification of words and non words:
* Non words: ving, fump, drace, biss
* Words: bear, wood, pint, sweat
Graph shows dyslexic readers name fewer objects and fewer correct words than the control group . Does not mean they cannot do the task, but with less fluency or speed.
What are the dyslexic profiles?
Poor phonological awarness: problems iding phonemes and reading non-words
Slow lexical retrieval: RAN task - slow retrieval of letter. Slower word reading for dyslexic group compared to weak and normally developing readers
How does the DRC model explain dyslexia?
a child is struggling to read a real word they could have a deficit in either route. Problems with the non lexical route would make de-coding a word difficult. Problems with the lexical route would make accessing an orthographic representation difficult.
A problem with the non-lexical route could mean that a child was not very good at activating a phonological representation and that could affect their ability to form orthographic representations.
On the other hand problems reading non-words suggests a deficit in the non-lexical route as it is not possible to read non words via a lexical route
Problem/defict in the non-lexical route would lead to what kind of problem?
lead to problems reading on-words and could lead to problems in the lexical route
What do phoneme and grapheme problems result in ealry and later stages of life?
Initial problems results in problems with word reading later in development. Reflected in slower identification and reading of correct words in later stage of development.
Difficulties in reading later in life may be due to phonological deficit when learning to read – less robust orthographic lexicon – less fluidity in reading.
Key time for learning to read based on phonological processing, difference most pronounced.
What does reading faciliate?
Reading (exposure to print) facilitates the development of an orthographic lexicon
What facilitates skilled reading?
Development of an orthographic lexicon facilitates ‘skilled’ reading
1.
Do decoding skills create opportunities?
Share 2011
YES, Decoding skill creates opportunities for self-teaching but does not guarantee that orthographic learning will take place”
How is orthographic learning affected by phonological processes?
- Weak phonological processes affect the formation of orthographic representations
- The result could be an *‘Unexpectedly poor speller’ or a subtype of dyslexia called ‘Surface’ Dyslexia: *Typical decoding, reading speed but difficulty in spelling
What’s surface dyslexia?
Phonological awareness appears unimpaired
Non-word reading is within a ‘normal’ range
Irregular word reading is impaired – break is read as ‘breek’
Unable to distinguish between homophones – difficulty telling which of the following is a vegetable been or bean
What is it like to read irregular words with surface dyslexia?
If your lexical route in impaired but your non lexical route is intact you may struggle to read irregular words because you do not have access to strong orthographic representations
How are reading impairment profiles tested?
Tests of irregular compared to regular word reading have highlighted differences in dyslexic profiles
Are there any surface dyslexia subtypes of dyslexia?
Bailey et al (2004) Surface dyslexics had difficulty learning a set of irregular words such that they could recognise them and read them out loud.
Ziegler et al. (2008) found evidence of a surface dyslexic subtype in children diagnosed with developmental dyslexia compared to a chronological age control group.
Friedmann & Coltheart 2016 describe varity of types of developmental dyslexia
What is surface dyslexia?
Deficits to the lexical Route, problems reading regular non-words. Problems reading irregular words
What is phonological dyslexia?
honological dyslexia: Deficits to the non-lexical route. Problems reading non-words. Impairment of non-lexical (GPC) route
Are there actually different types of dyslexia?
Review Sprenger-Charolles & Semiclaes 2003
These results are more in line with the hypothesis that a phonological deficit is at the core of developmental dyslexia, than with the idea that a clear dissociation exists between surface and phonological profiles.
What compensatory mechanism is used when reading by dyslexics?
As a compensatory mechanism, they tend to rely more on semantic processing for reading than their typically reading peers. That is, stronger influences of semantics on word reading can be expected in this group compared with typical readers
What happens if a child isn’t as good at using their non-lexical route to decode words?
If a child is not very good at using their non lexical route to de-code words they may still be able to access some phonemes in a word. This may result in activation of a list of candidate words that could fit the partial de-coding. If a child can use context to disambiguate the situation, they may be able to work out which word they are seeing.
How does context impact lexical access?
The language system predicts which words might come up next and activates them in the lexicon. It is possible that due to problems reading words dyslexic readers have stonger predicting mechanisms that rely on context.
How does dyslexia affects semantic processing?
Frith & Snowling 1983
Tested children’s ability to correctly read out loud sentences that ended with a homograph (spelled the same – pronounced differently). Before he made his speech he gave a bow. Dyslexic children were more likely to correctly pronounce ‘bow’ than controls
What did Nation & Snowling 1998 found on reading words in context?
Tested children’s ability to correctly read regular and irregular words in isolation and their ability to correctly read regular and irregular words after hearing a sentence.
Dyslexic readers use context to process both regular and irregular words more than normal readers. Normal readers use context more for irregular compared to regular word reading
What is semantic priming effects ?
A measure of semantic processing that can be used to explore these effects is semantic priming. If an individual has stronger predictive processing and links between semantic concepts they should have larger semantic priming effects.
What is the priming paradigm and the semantic priming effect?
NURSE
Doctor = prime, NURSE = target (related condition)
Sheep = prime, NURESE = target (unrelated condition)
Reaction time (RT) to the word NURSE.
Related condition = 450ms
Unrelated condition = 600ms
-> Priming effect = 150ms
What is semantic priming effects in picture word priming task?
Van der Kleij et al 2019
Dyslexic readers show larger semantic priming effects than normal readers.
The evidence presented here also suggests that dyslexic readers are able to use context to a greater extent than normally developing readers
What do dyslexic children may acquire to compensate for weaker phonological processing?
stronger semantic processing
