Dyslexia

Question 1

What percentage in UK across social groups have Dyslexia?
What percentage leave school unable to read properly?
What percentage of convicted criminals are illiterate?

Answer 1

10%
20%
75%

Question 2

What 5 things do children with dyslexia present with?

Answer 2

problems with nursery rhymes and other language games
problems with reading and writing at school
avoids reading activities
dyslexia in the family
disorganised and forgets things easily

Question 3

What 4 things do adults with dyslexia present with?

Answer 3

find it hard to remember 2 or 3 instructions together
delay between hearing and understanding words
had problems with reading and spelling at school
dyslexia in your family

Question 4

What are the three clinical characteristics of ADHD in children?

Answer 4

Symptoms for at least 6 months, despite specific interventions
Impairment of single or more abilities, with negative effects on school achievement
Onset in a school-age, even if the disorder persists later

Question 5

What has to be ruled out in a clinical diagnosis of dyslexia?

Answer 5

intellectual disability  
fragmentary and inadequate instruction 
sensory problems (visual and auditory sensory problems) 
lack of linguistic proficiency in the language used for academic instruction

Question 6

Name some tests for dyslexia

Answer 6

Background (Family history/ delays and difficulties speech & language)
Intelligence
Oral language skills
Word recognition (reading)
Decoding (letter sound knowledge–read nonsense words)
Spelling
Phonological Processing (link letters to sounds)
Fluency (Rapid automated naming)
Reading comprehension
Vocabulary

Question 7

Where do lesions that result in alexia occur?

Answer 7

Angular gyrus

Question 8

What brain areas are affected in adult dyslexia?

Answer 8

 Left lateralised
 Superior middle and temporal-parietal
 Visual word form area

Question 9

What does the brain look like during development in dyslexics?

Answer 9

 Less lateralised

 VWFA develops gradually

Question 10

What areas are hypoactivated?

Answer 10

 Temporal
 Parietal
 Fusiform area

Question 11

What areas are hyperactivated?

Answer 11

 Inferior frontal

Question 12

What are the rates of heritability of dyslexia in studies like the Florida twin study?

Answer 12

about 50 to 60%.

Question 13

What are the two genes involved in dyslexia?

Remember- Washington doubles, Kryptonite is absolute agony on the 19th March

Answer 13

• DCDC2

* KIAA0319

Question 14

The combination of risk alleles increasing chances of developing dyslexia is known as…

Answer 14

Polygenic risk

Question 15

What are four issues with GWA studies?

Answer 15

• Requires very large samples
• Small effects / explain small portion of variance
• Poor replicability
• GWAS miss genuine but small effects

Question 16

Issues with GWA studies specifically for dyslexia?

Answer 16

2% of children with dyslexia have both genetic variants
Even though variant of KAA0319
 present in 25% diagnosed with dyslexia
 present in 39% normal readers

Question 17

Phoneme hypothesis:
What is it?
What are its three specific impairments?
How is it assessed?

Answer 17

Best recognised cause of Dyslexia 
Identifying sounds that connect written to spoken words
	specific impairment in 
•	representation
•	storage 
•	retrieval of speech sounds. 
	assessed by reading pseudo-words

Question 18

Main challenge to Phoneme hypothesis?

Answer 18

Other disorders with phonological deficits have no reading difficulty

Question 19

Magnocellular hypothesis:
What are the Magnocellular pathways?
What is the nucleus involved?
Which sense does is it involved in?
What does it look like in dyslexia?

Answer 19

•	neural pathways that connect the sensory organs to the cerebrum via the thalamus. 
•	Lateral Geniculate Nucleus (LGN)
o	Dorsal, Where , vision 
Magnocelluar 
	Large cells in retina 
	Sensitive to motion 
	Sensitive to low contrast
o	Left side abnormally small in Dyslexia

Question 20

Arguments against the Magnocellular hypothesis?

Answer 20

o Magnocellular abnormalities result not cause of dyslexia
• Motion perception is not necessarily magno
• Doesn’t explain phonological deficits
• Not always found

Question 21

Cerebellar hypothesis:
Reading difficulties are due to..
Pattern of activation in cerebellum?

Answer 21

 Reading difficulties due to skill learning issues

 Cerebellum is active during early stages of skill learning, but less active when the skill becomes automatized

Question 22

Evidence for cerebellar hypothesis in dyslexia?

Answer 22

• appear clumsy
• have motor impairments
• MRI studies show cerebellar abnormalities

Question 23

Evidence against cerebellar hypothesis in dyslexia?

Answer 23

• Almost all studies show correlation of phonological abilities and reading
• Many fewer show correlations with balance and other motor skills
• Interventions based on exercise controversial
• Large scale study

Question 24

Neural noise hypothesis?

Negative association between … and … concentrations are positively correlated with …

Answer 24

Negative association between children’s reading skill and glutamate MRS glutamate concentrations are positively correlated with cortical excitability