Free CALT Neurobiology of Reading and Dyslexia Questions and Answers 1 — Questions and Answers
Question 1: Neuroimaging studies of individuals with dyslexia often show underactivation in which posterior brain region during reading tasks?
- The right prefrontal cortex
- The left occipito-temporal region (Correct answer)
- The hippocampus
- The cerebellum
Correct answer: The left occipito-temporal region
The left occipito-temporal region, often called the Visual Word Form Area (VWFA), is critical for skilled, automatic recognition of words. Research consistently shows that this area is underactivated in individuals with dyslexia when they are trying to read, reflecting a disruption in the brain's expert reading system.
Question 2: In the typical reading brain, what is the primary function of Broca's area, located in the left inferior frontal gyrus?
- Processing the visual features of letters and words.
- Storing long-term memories of stories.
- Phonological processing and verbal articulation of words. (Correct answer)
- Accessing the meaning (semantics) of words.
Correct answer: Phonological processing and verbal articulation of words.
Broca's area is crucial for language production and articulation. In the context of reading, it is involved in phonological processing, such as silently pronouncing words, analyzing their sound structure, and understanding grammatical rules.
Question 3: What does fMRI research reveal about the brains of individuals with dyslexia following intensive, evidence-based reading intervention?
- No significant changes occur in brain function, as dyslexia is a permanent condition.
- The brain permanently shifts all reading functions to the right hemisphere.
- There is increased activation in left-hemisphere posterior reading systems. (Correct answer)
- Overall brain activity decreases as reading becomes easier.
Correct answer: There is increased activation in left-hemisphere posterior reading systems.
Effective intervention can physically change the brain. Studies show that after successful remediation focusing on phonics, the brains of individuals with dyslexia show increased activation in the left-hemisphere systems that were previously underactive, and their brain activity patterns begin to resemble those of typical readers.
Question 4: The 'Double-Deficit Hypothesis' of dyslexia posits that an individual's reading difficulty is most severe when they have weaknesses in both:
- Phonological awareness and rapid automatized naming (RAN). (Correct answer)
- Visual acuity and auditory processing.
- Working memory and verbal comprehension.
- Executive function and attention.
Correct answer: Phonological awareness and rapid automatized naming (RAN).
Proposed by Maryanne Wolf and Patricia Bowers, this hypothesis suggests that dyslexia can result from a deficit in phonological awareness, a deficit in rapid naming speed, or a combination of both. The most severe and persistent reading difficulties are seen in individuals who have deficits in both areas.
Question 5: Which brain region acts as a crucial hub for linking the visual representation of a word (graphemes) with its sound structure (phonemes)?
- The amygdala
- The motor cortex
- The angular gyrus (Correct answer)
- The brainstem
Correct answer: The angular gyrus
The angular gyrus is considered a critical cross-modal association area. For reading, it plays a key role in integrating visual information from the occipital lobe with phonological information processed in the temporal lobe, effectively 'sounding out' a written word.
Question 6: How does the neurobiology of dyslexia provide a rationale for using a Multisensory Structured Language (MSL) approach?
- It proves that dyslexia is caused by poor vision and can be corrected with eye exercises.
- It demonstrates that the brain's reading pathways are weak and benefit from explicit, multimodal instruction to be strengthened. (Correct answer)
- It suggests that individuals with dyslexia learn best through incidental, discovery-based learning.
- It indicates that reading intervention is only effective when delivered via computer software.
Correct answer: It demonstrates that the brain's reading pathways are weak and benefit from explicit, multimodal instruction to be strengthened.
Since neurobiology shows that the typical neural pathways for reading are inefficient in dyslexia, MSL aims to build and strengthen these pathways through alternative means. By explicitly teaching the structure of language and engaging multiple sensory systems (visual, auditory, kinesthetic), MSL provides a robust, redundant signal to the brain, helping to forge the connections needed for literacy.
Neuroimaging studies of individuals with dyslexia often show underactivation in which posterior brain region during reading tasks?