CDT Foundations of Dyslexia & Language-Based Learning Disabilities 2 — Questions and Answers
Question 1: Which brain imaging finding is most consistently associated with dyslexia in neurological research?
- Enlarged corpus callosum
- Reduced activation in left temporoparietal regions during reading (Correct answer)
- Increased gray matter in the right frontal lobe
- Overactivation of the visual cortex
Correct answer: Reduced activation in left temporoparietal regions during reading
fMRI studies consistently show reduced activation in left temporoparietal areas (including the angular gyrus and Wernicke's area) in individuals with dyslexia during reading tasks.
Question 2: The 'Simple View of Reading' (Gough & Tunmer, 1986) defines reading comprehension as the product of which two components?
- Phonological awareness and vocabulary
- Decoding and linguistic comprehension (Correct answer)
- Fluency and background knowledge
- Word recognition and working memory
Correct answer: Decoding and linguistic comprehension
The Simple View of Reading formula is RC = D × LC, meaning Reading Comprehension equals Decoding multiplied by Linguistic Comprehension.
Question 3: Dyscalculia that co-occurs with dyslexia is best described as which type of comorbidity?
- Mutually exclusive condition
- Coincidental overlap with no shared etiology
- Comorbid condition sharing some neurological risk factors (Correct answer)
- Secondary consequence caused exclusively by dyslexia
Correct answer: Comorbid condition sharing some neurological risk factors
Dyscalculia and dyslexia frequently co-occur and share some genetic and neurological risk factors, though they also have distinct etiological pathways.
Question 4: Which term describes the phenomenon where a child with dyslexia reads words correctly but very slowly and with great effort?
- Hyperlexia
- Compensated dyslexia
- Dysfluent decoding (Correct answer)
- Orthographic mapping failure
Correct answer: Dysfluent decoding
Dysfluent decoding refers to accurate but labored, slow word reading that still reflects the core deficit in phonological processing even when accuracy improves.
Question 5: According to the IDA definition, which of the following is NOT a primary characteristic of dyslexia?
- Difficulties with accurate word recognition
- Difficulties with decoding
- Difficulties with spelling
- Difficulties with reading comprehension caused by poor listening comprehension (Correct answer)
Correct answer: Difficulties with reading comprehension caused by poor listening comprehension
The IDA definition specifies that reading comprehension difficulties in dyslexia result from deficits in phonological processing, not from poor listening/language comprehension (which would indicate a different profile).
Question 6: The 'Wolf Naming Speed Deficit' refers to deficits in which cognitive process that is separate from phonological awareness?
- Verbal working memory
- Rapid automatized naming (RAN) (Correct answer)
- Orthographic processing speed
- Phoneme segmentation
Correct answer: Rapid automatized naming (RAN)
Maryanne Wolf's research identified rapid automatized naming (RAN) as a second core deficit in dyslexia, distinct from phonological awareness, leading to the double-deficit hypothesis.
Question 7: Which genetic finding best supports the hereditary nature of dyslexia?
- Dyslexia occurs in 100% of identical twins
- Heritability estimates range from 40–70% with multiple candidate genes identified (Correct answer)
- A single dominant gene on chromosome 6 causes all cases
- Only maternal inheritance patterns have been confirmed
Correct answer: Heritability estimates range from 40–70% with multiple candidate genes identified
Twin and family studies show heritability estimates of 40–70% for dyslexia, with multiple candidate genes (e.g., DCDC2, KIAA0319) identified on several chromosomes.
CDT Foundations of Dyslexia & Language-Based Learning Disabilities 2
Which brain imaging finding is most consistently associated with dyslexia in neurological research?