Cours : Developmental Dyslexia

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Questions and Answers

What is the main reason for the increase in heritability of reading skills with age?

Genes become more dominant as children age.

Older students have access to more advanced reading instruction.

Older children are more likely to select environments that reinforce their reading abilities. (correct)

Older children are more likely to have dyslexia.

What is the 'Matthew effect' in the context of reading?

Poor readers are more likely to be diagnosed with dyslexia.

The impact of genetics on reading ability increases with age.

Good readers tend to read more, becoming better readers, while poor readers avoid reading. (correct)

Good readers are more likely to be diagnosed with dyslexia.

What is the estimated familial risk for dyslexia?

10-20%

40-60% (correct)

20-30%

70-80%

What does 'heritability' refer to in the context of reading skills?

The proportion of variance in reading skills attributable to genetic influence. (B) Signup and view all the answers

What is the heritability of reading skills at age 6?

0.22 (C) Signup and view all the answers

What is the approximate heritability for cognitive skills related to reading?

40-70% (B) Signup and view all the answers

What is the most likely reason for the difference in heritability between reading skills at age 6 and age 12?

Increased niche selection. (D) Signup and view all the answers

Which of the following is NOT a factor contributing to the multifactorial nature of dyslexia?

Intelligence Quotient (IQ) (A) Signup and view all the answers

Which of these findings were reported by Giallusi et al.?

A single nucleotide polymorphism (SNP) with self-reported dyslexia from 51’800 individuals and 1’087’070 controls. (B) Signup and view all the answers

What does the abbreviation SNP stand for?

Single nucleotide polymorphism (A) Signup and view all the answers

What is the main focus of the content?

The genetic factors involved in dyslexia (C) Signup and view all the answers

Which of these could be considered a candidate gene for dyslexia?

All of the above (D) Signup and view all the answers

What does 'GWAS' stand for?

Genome Wide Association Studies (B) Signup and view all the answers

What is the estimated prevalence of developmental dyslexia?

5-7% (A) Signup and view all the answers

What is the typical gender ratio of males to females affected by developmental dyslexia in community samples?

1.5:1 to 3:1 (C) Signup and view all the answers

A child is diagnosed with developmental dyslexia based on standardized test results. Which of the following criteria is used to determine the diagnosis?

Performance in reading and/or writing tests clearly below average in a standardized test with a significant discrepancy to age or IQ norms. (A) Signup and view all the answers

What does the text describe as a possible indicator of severe difficulties in reading and/or writing?

PR ≤ 16 (1 SD) (C) Signup and view all the answers

Based on the text, what does the acronym "PR" likely refer to?

Percentile Rank (C) Signup and view all the answers

Which of the following is a characteristic of spelling problems in children with dyslexia?

Children make more errors, but there are no identifiable patterns or "dyslexia-specific" errors. (A) Signup and view all the answers

The text highlights that developmental dyslexia is present in various cultures and languages. What does the text say about its prevalence across different languages?

Prevalence is similar across different languages, with a 1 SD cutoff around 7%. (A) Signup and view all the answers

What is a key factor that contributes to the development of reading and writing difficulties?

Familial Risk. (D) Signup and view all the answers

What does the example text reading test in the 5th grade demonstrate?

A child with dyslexia struggling to read fluently, making multiple errors. (A) Signup and view all the answers

Based on the provided information, what is likely the primary focus of the document?

Presenting the diagnostic criteria and characteristics of developmental dyslexia. (B) Signup and view all the answers

What does the acronym "MRI" stand for, as used in the provided content?

Magnetic Resonance Imaging (B) Signup and view all the answers

Which of the following are NOT measured by functional MRI? (Select all that apply)

The specific location and size of brain tumors (B), Characteristics of brain tissue like grey matter and white matter (C) Signup and view all the answers

What is the name of the core reading region whose variability in grey matter volume can be explained by NRSN1 gene variants?

Visual Word Form Area (VWFA) (B) Signup and view all the answers

According to the content, what is the main difference between the functional brain activations in dyslexic individuals compared to controls during a word reading task?

Dyslexic individuals have increased activation in the precentral gyrus, while controls have a higher activation in the temporo-parietal cortex (A) Signup and view all the answers

Which of the following factors is NOT stated to be related to dyslexia in the content provided?

Reduced cognitive abilities, particularly in terms of working memory and attention (G) Signup and view all the answers

What specifically are "copy number variants" (CNVs) in the context of dyslexia?

Variations in the number of copies of specific genes on a chromosome (B) Signup and view all the answers

According to the provided content, what is the relationship between the "visual word form area" (VWFA) and dyslexia?

Individuals with dyslexia have smaller VWFA volumes compared to controls, suggesting issues with visual word form processing. (B) Signup and view all the answers

Which of the following is NOT mentioned in the content as a possible consequence of having copy-number variants (CNVs) related to dyslexia?

Impaired visual perception, leading to difficulties with letter recognition (B) Signup and view all the answers

Based on the content, which of the following brain regions is directly related to phonological processing and lexical access in dyslexia?

Inferior frontal gyrus (A) Signup and view all the answers

What is the main takeaway from the study by Fedorenko et al. (2024) regarding language and reading in the brain?

There are two distinct pathways for reading in the brain, one phonological and one visual, both equally important for successful reading. (E) Signup and view all the answers

What is the main difference between the two pathways for reading in the brain?

One pathway is responsible for recognizing the visual form of words, while the other is responsible for decoding the sounds of words. (E) Signup and view all the answers

Which brain region is NOT associated with phonological processing according to the content?

Occipito-temporal cortex (VWFA) (B) Signup and view all the answers

What is the importance of the NRSN1 gene variants in the context of dyslexia?

They are associated with variations in grey matter volume in the VWFA, influencing reading abilities. (A) Signup and view all the answers

What does the content suggest about the role of genetics in dyslexia?

Genetics contribute to the development of dyslexia, influencing brain structure and function, but environmental factors also play a role. (B) Signup and view all the answers

Based on the provided content, what is the relationship between the precentral gyrus and dyslexia?

Individuals with dyslexia show increased activation in this area, suggesting compensatory mechanisms. (C) Signup and view all the answers

Which of the following is NOT listed as a precursor to reading?

Visual memory (C) Signup and view all the answers

Which of the following is NOT mentioned as a contributing factor to dyslexia?

Environmental factors (C) Signup and view all the answers

Which of the following cognitive skills is primarily affected by dyslexia?

Phonological processing (B) Signup and view all the answers

Which of the following is an example of phonological awareness?

Recognizing rhyming words (D) Signup and view all the answers

What does RAN (Rapid Automatized Naming) measure?

The ability to quickly and accurately identify objects, colors, or letters (D) Signup and view all the answers

Which of the following is NOT a symptom of dyslexia?

Struggles with mathematical calculations (B) Signup and view all the answers

What is the importance of understanding the multifaceted nature of dyslexia?

All of the above. (D) Signup and view all the answers

Which of these is a gene associated with dyslexia?

DCDC2 (B) Signup and view all the answers

Why is dyslexia testing typically done after school grade 2?

Because the current diagnostic approach prioritizes identifying children who are struggling significantly with reading and writing. (D) Signup and view all the answers

Based on the provided information, which of these is NOT a potential factor contributing to dyslexia?

Lack of adequate reading instruction (D) Signup and view all the answers

Which of the following is NOT a symptom of dyslexia, as mentioned in the content?

Challenges with basic motor skills (B) Signup and view all the answers

The suggested approach of early intervention for dyslexia involves:

Identifying potential risks for dyslexia before children begin formal reading instruction. (D) Signup and view all the answers

The term 'speech-print association' refers to:

The ability to associate spoken words with their written counterparts. (D) Signup and view all the answers

Which of the following represents a misconception related to dyslexia?

Dyslexia is primarily a problem with visual perception. (A) Signup and view all the answers

Why is the gene 'DCDC2' mentioned in the context of dyslexia?

It is a gene that is involved in the development of language and reading skills. (D) Signup and view all the answers

What does the term 'multifactorial origin' suggest about dyslexia?

Dyslexia is a result of a complex interplay of different factors. (B) Signup and view all the answers

Study Notes

Developmental Dyslexia

Developmental dyslexia is a specific learning disorder.
It is characterized by significant and persistent difficulties in learning the basic reading skills
Males are more often affected than females, with a ratio ranging from 1.5:1 to 3:1.
The prevalence of developmental dyslexia (reading and writing) is estimated at about 5-7%
People with this disorder often struggle with spelling, word recognition, and phonological processing.
Commonly seen in children and can persist into adulthood.

Reading Competence in Europe & Switzerland

PISA studies assess reading competence every three years.
Data from 2022 shows significant variation in reading competence across European countries.
In Switzerland, 14-16% of adults and almost 25% of adolescents demonstrate insufficient reading competence.

Diagnosis of Developmental Dyslexia

Not all individuals with poor reading competence have developmental dyslexia.
It is critical to distinguish learning differences from dyslexia.

Characteristics of Developmental Learning Disorders

Significant and persistent difficulties in learning academic skills
Performance significantly below expected levels for age
Significant impairment in academic or occupational functioning

Exclusion Criteria for Developmental Learning Disorders

Limitations not attributable to external factors (e.g., economic, environmental disadvantages).
Learning difficulties not better accounted for by another disorder, e.g., intellectual disability.
Exclusion includes any other conditions like a motor or sensory disorder (vision or hearing).

Diagnostic Criteria for Reading and Writing Disorders

Performance in reading and/or writing tests below average for age
Discrepancy between performance and cognitive ability needed for testing.

Testing Reading Competence

Use of a standardized test (e.g., Salzburger Reading Test)
Participants read aloud fantasy words within 1 minute – this test is not a valid diagnostic tool during this course.

Causes of Dyslexia

Multifactorial, involving multiple genes and environmental risk factors.
Heritability estimated to be between 40-60%.
There's a complex interplay of genetic, environmental, and brain development factors.

Molecular Mechanisms

Potential genes involved in dyslexia include KIAA0319, DCDC2, and DYX1C1 and others.
Neuronal migration and connectivity in specific brain regions play a crucial role.

Comorbid Symptoms

40-60% of children diagnosed with learning disorders (dyslexia) also have comorbid disorders.
Common co-occurring conditions include ADHD, dyscalculia, depressive disorders, and anxiety disorders.
Adolescents with reading difficulties often experience increased rates of school dropout, negative experiences at school, and other possible psychological problems.

Prevalence of Dyslexia Across Languages and Writing Systems

Similar prevalence rates of dyslexia across various languages and writing systems.
Similar prevalence across different grades.
Research indicates variations slightly increase the risk across ages and genders

Early Differences in Reading Precursors

Phonological awareness
Letter knowledge
Rapid automatized naming (RAN) speed (e.g., of objects)

Brain Structure, Function, and Connectivity

Structural and functional alterations in the brain may be related to dyslexia
MRI scans can be used as a measurement to evaluate this condition

Waiting to Fail in Dyslexia

Diagnostic approach often delayed, sometimes until second grade or later.
Early identification and intervention to address developmental dyslexia have proven to be crucial for success.

Example Texts and Word Readings

Provide example reading material and word lists for practice, used in the given classes and sessions.

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Description

Explore key concepts surrounding dyslexia, reading skills, and their hereditary aspects in this quiz. Assess your understanding of terms like heritability, the Matthew effect, and familial risks associated with dyslexia. Additionally, delve into genetic implications and research findings related to reading difficulties.