Week 7 - Deep Dyslexia Flashcards Preview

3019PSY CogNeuroPsych > Week 7 - Deep Dyslexia > Flashcards

Flashcards in Week 7 - Deep Dyslexia Deck (38)
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1
Q

Dyslexia

A
• Dyslexia = reading disorder
• Problem going from print to pronunciation of
item
• Acquired dyslexia
• Developmental dyslexia
2
Q

Deep Dyslexia

A

• First systematic study – Marshall & Newcombe
(1966)
• Typically an acquired reading impairment
• Cases of developmental Deep Dyslexia in the
literature
• Defining symptom semantic error in reading
aloud

3
Q

• Symptoms of Deep Dyslexia

A

• Unvarying across cases of Deep Dyslexia

4
Q

• Key symptom

A

• Semantic errors in reading single words out loud

eg. tandem > say “cycle” instead
cost > say “money”

5
Q

• Visual errors

A

produce a word that looks similar to the presented word

eg. signal > single

6
Q

• Visual-then-semantic errors

A

Visual error first than a semantic error on the replacement word:

eg. sympathy (symphony) > then say “orchestra”
favour (flavour) then say > “taste”
charter (chart) > map

7
Q

What is the imagability effect?

A

• Better at reading concrete than abstract
words
eg − Better at saying butter and windmill than grief and
wish

8
Q

Errors with abstract words are….

A

when trying to read abstract words will create visually related but highly imageable words, eg wish > wash
wash more concrete (highly imageable)

9
Q

better at content than…

A

function words
 Content words (nouns, verbs, adjectives)
 Function words (was, quite, of)

10
Q

• Function word errors

A

Different kind of function word

Was > with
If > yet
Quite > perhaps
(no access to semantic system) (can access the function word store but get it wrong)

11
Q

• Morphological errors (derivational errors)

A

put letters in wrong place (listen to lecture)
eg. edition > editor
Courage > courageous
(derivational errors)

12
Q

Very poor _____reading (____words)

A

nonword; nonsense
eg - brane, phocks

(GPC impaired)

Spelling and writing may be impossible
• If possible then symptoms are equivalent to
those listed above
• All patients with deep dyslexia show all of
these symptoms

13
Q

Explanations for Deep Dyslexia

A
• Impairment(s) to the normal left hemisphere
reading system through many different
approaches
OR
• Reading occurs via a secondary right
hemisphere reading system
14
Q

Impairment to left hemisphere reading

system

A

• Deep Dyslexia patient reads via a multiply
damaged LH (Morton & Patterson, 1980)
• Nonword reading abolished – letter to sound rules abolished
• Direct connection between orthographic input lexicon and the phonological output lexicon
must be impaired as word reading is poor
• Function words – can do visual LDT and can
produce them as they typically make function
word substitution errors
• Problem must be one between word
recognition and word production
• Reading worse for abstract than concrete words, impairment semantic system that is
worse for abstract than concrete words
• Semantic system impaired  semantic errors
e.g. canary  parrot
• Damage to connection between semantic system and phonological output lexicon
• Deep dyslexic correctly understands a printed
word but makes a semantic error reading it
• Damage to component syntactic system processes prefixes and suffixes (morphological
errors in reading affixed words)

15
Q

Right hemisphere hypothesis

A

• Both LH and RH approaches agree reading occurs
via orthography, phonology and semantics
(Coltheart, 2000).
• If LH cannot do one of these processes then RH
must take over
• Coltheart (1980) Deep Dyslexia loss access from
print to the LH orthographic lexicon
• Deep Dyslexia reads “word” via RH orthographic
lexicon  semantic representation  information
send to LH phonological lexicon to retrieve
phonology (“say word aloud”)

16
Q

Right hemisphere reading

A

• Semantic errors – incorrect selection of target
from activated candidates  LH
• Activation of nonword phonology in RH nonexistent
– cannot say nonwords
• Errors deep dyslexia due to use RH reading
system

17
Q

Brain Damage

A

• Widespread damage to left hemisphere
• Developmental case – no damage cortex or
white matter
• Orthographic processing – left occipital and
occipitotemporal regions
• Semantic processing – border between superior
and middle temporal gyrus, areas BA21 and
BA22 (LH)
• Phonological output – LH frontal operculum

18
Q

Diagnosis and rehabilitation of Deep
Dyslexia patient
Ska, Garneau-Beaumont, Chesneau &
Damien (2003)

A

Diagnosis and rehabilitation of DD patient
• Ska, Garneau-Beaumont, Chesneau & Damien
(2003)
• Assess reading of DD patient according to a
cognitive model of reading
• Assess a priming paradigm rehabilitation program
focus on the lexical route to reading aloud
• Patient JH 56 yrs old in 1997
• Suffered a left ischemic cereal vascular Sylvain
stroke following a triple aorta-coronary by-pass
operation
• Right hemianopsia, right brachio-facial
hemiparesis and receptive and expressive aphasia
symptoms

Diagnosis and rehabilitation of DD patient
• Appeared to have DD
• JH right handed physician, multi-lingual
• One year JH individually followed by speech
therapist 4 x week
• Two years in a rehabilitation program, 3
individual therapies a week, exercises to be
done at home and a weekly group therapy
session
• Dec 2000 JH began rehabilitation for his reading
problems

19
Q

Assessment of JH’s Deep Dyslexia (DD)

Peripheral processes

A
 Matching identical words
 Letter identification among visually similar
letters
 Letter identification among auditorily similar
letters
 Letter denomination
 Word and nonword repetition
 Unexpected delay repetition of words
20
Q

Peripheral Processes

A

• Assess being able to process auditorily
presented words
• Repeat words & nonword aloud
• Match letters to spoken letters
• Also process individual letters that were
visually presented

21
Q

Assessment of JH’s Deep Dyslexia (DD)

• Phonological route

A
Letter Reading (YES!)
Phoneme Reading (No)
Phoneme Identification (No)
22
Q

Phonological route

Grapheme-phoneme route

A
  • Letter reading
  • Phoneme reading
  • Phoneme identification
23
Q

Assessment of JH’s Deep Dyslexia (DD)

• Lexical route

A

Reading words aloud - (No)

Reading non-words (no)

24
Q

Assessment of JH’s Deep Dyslexia (DD)

• Assessing linguistic variables

A
  • Word length effect
  • Word frequency
  • Orthographic complexity
  • Concrete vs. abstract words
25
Q

Assessment of JH’s Deep Dyslexia (DD)

• Error analysis

A

– semantic, phonological, visual,

morphological

26
Q

Assessment of JH’s Deep Dyslexia (DD)

• Phonological lexicon

A

 auditory lexical decision task (yes)

27
Q

Assessment of JH’s Deep Dyslexia (DD)

• Orthographic lexicon

A

Failed - visual lexical decision

Passed - Irregular words letter switch task

28
Q

Lexical Route (orthographic route)

A

•Reading words
•Reading non-words (type of errors relevant here)
•Visual lexical decision and letters switched within
a word
•Word length, frequency effects and orthographic
complexity
•Concrete vs. abstract (link with semantic system)

29
Q

Assessment of JH’s Deep Dyslexia (DD)

• Semantic system

A

Passed all the following:

Odd item
Odd item with subtle relations
Written word-picture matching
Semantic relation between picture and
written word
Picture-written word matching
30
Q

Assessment of JH’s Deep Dyslexia (DD)

• Semantic system

A

failed all:
X Odd item
X Odd item with visually similar words
X Semantic matching

31
Q

Semantic system

what, tests?

A

•Odd items
•Written word-picture matching
•Semantic relations between picture and word
•Picture-written word matching
•Matching and semantic relations task using only
verbal input

32
Q

Assessment of JH’s Deep Dyslexia (DD)

• Phonological output lexicon

A

Passed:

Picture naming task
Semantic association task

Failed:

X Homophones
X Word designation

33
Q

Phonological output lexicon

A
  • Picture naming task
  • Semantic association task
  • Homophones
  • Word designation
34
Q

JH’s Deep Dyslexia (DD) summary

A

• Impaired phonological route to reading aloud
• Orthographic route to reading aloud impaired
even though he can read irregular words aloud
• Errors – semantic, morphological, phonological
for reading real words
• JH has deep dyslexia

35
Q

Rehabilitation of JH’s Deep Dyslexia (DD)

A

• Aim to use matching pictures to their written
labels to build a new lexicon
• Tasks & Method: pre-test 140 concrete written
words (76 low freq, 64 high freq.)
• At pre-test 34 (24%) words read correctly
• No frequency effect
• 50 words that were badly read or not read were
selected for use in the training program
• Other 56 words not use in training
• Post-test: 140 words presented for reading aloud
• Post-test: run 1 week after rehab program, 8
month follow-up

36
Q

Rehabilitation of JH’s Deep Dyslexia (DD)

• Training

A

• Weekly session with speech therapist.
• Words to be read aloud presented in blocks
• Each block practised once during a training
session
• Word written on one side of a card, picture and
word written on other side of card
• JH tried to read word alone, then look at picture
to identify word
• Word read by speech therapist
• JH invited to construct a mental association
between picture and written word

• Training (cont.)
• During the week JH read words twice a day
• Next session studied words assessed without
picture support and a new block of words
presented
• Final session were words presented that were
read incorrectly at the weekly meeting
• Total of five sessions
• Post-test and follow=up JH required to read all
140 words

37
Q

Rehabilitation Results

A

• Post-test 84/140 (60%) word read correctly
– Trained words 90% correct
– Non-trained words 18% correct
– Original words correctly read 85% correct
• 8 month follow-up JH read 260 words (140 old
words)
– 55% correct original 140 words
– 84% correct on trained words
– 25% correct non-trained words
– 62% original words correctly read

38
Q

Rehabilitation Implications

A

• After only 5 training sessions there was a
specific training effect
• No progress on control tasks
• Use of picture and auditory input assisted JH
• JH retained a high score on the trained words at
8 month follow-up despite no written contact
with these words during that time
• Training via the lexical route does not allow the
effects to generalise to learning new words
beyond those trained
• Training did increase JH’s motivation to continue
with reading