Dyslexia is a learning disorder that makes it difficult to interpret words, letters, and other symbols. People with dyslexia often have trouble matching letters to sounds, reading quickly, spelling correctly, learning a new language, and interpreting words. Dyslexia is one of the most common learning disabilities and affects people across languages and cultures.
What causes dyslexia?
Research shows that dyslexia is a neurobiological condition that runs in families. It is not caused by poor teaching, laziness, or lack of intelligence. Dyslexia arises from differences in how the brain processes written and spoken language. People with dyslexia may have weaknesses in:
- Phonological processing – Difficulty connecting letters to sounds
- Orthographic processing – Problems remembering words and letter sequences
- Processing speed – Slow reading and writing speed
- Auditory processing – Difficulty filtering meaningful sounds from background noise
- Visual processing – Problems with letter and number reversals
- Working memory – Trouble remembering information over short periods of time
These difficulties are present at birth and affect the learning process from early childhood. Dyslexia is not related to race, income, language, or intelligence. With the right support, people with dyslexia can succeed in school and later in life.
Is dyslexia genetic?
Research indicates that dyslexia runs in families and has a genetic component. Some of the key research findings include:
- Up to 50% of children with dyslexia have a parent or sibling with dyslexia
- Identical twins are more likely to share dyslexia compared to non-identical twins
- At least 11 genes have been identified that correlate with dyslexia risk
- Some genes linked to dyslexia affect how the brain forms connections
However, dyslexia does not follow clear Mendelian inheritance patterns like single-gene disorders. Most experts agree that dyslexia stems from complex interactions between multiple genetic and environmental factors. Having certain gene variants puts a child more at risk but does not necessarily mean they will develop dyslexia.
Brain differences
Brain imaging studies have identified structural and functional differences in the brains of people with dyslexia compared to typical readers. Key differences include:
- Less gray matter volume in several regions involved in reading
- Less white matter connectivity between brain hemispheres
- Differences in how the visual cortex processes text and symbols
- Abnormalities in how the auditory cortex represents speech sounds
- Overactivation and underactivation patterns in certain networks
Some of these brain differences are present at birth, while others emerge as the child develops reading skills. Overall, research indicates that dyslexia stems from genetic influences on how the reading network in the brain forms before and after birth.
When are signs of dyslexia noticeable?
Here is the typical developmental timeline of when signs of dyslexia emerge:
- Preschool years – Delayed speech, struggles learning rhymes, confusion with directions
- Kindergarten and 1st grade – Difficulty recognizing letter names and sounds, trouble learning to read
- 2nd and 3rd grade – Very slow and inaccurate reading, trouble spelling common words
- 4th grade and up – Avoids reading aloud, poor reading comprehension, difficulty learning a foreign language
However, some children with dyslexia are not identified until later grades when reading demands increase. Warning signs in a school-age child include:
- Avoiding reading and writing
- Letter and number reversals past age 7
- Poor handwriting
- Trouble decoding unfamiliar words
- memorizing math facts or foreign words
Early identification and support are key to helping children with dyslexia achieve success in school. However, it is never too late to get help.
Can you develop dyslexia later in life?
Dyslexia is a lifelong condition that starts in childhood. The symptoms may change over time but do not emerge for the first time in adulthood.
However, some people are not diagnosed with dyslexia until later in life. Reasons this may happen include:
- High intelligence helps compensate for dyslexia difficulties during school years
- Less reading focus in the curriculum
- Support from parents or tutors masks the problem
- Lack of teacher awareness about dyslexia
- It may be mistaken for other learning or attention disorders
Events like a job change, taking a foreign language class, or needing stronger reading skills can reveal undiagnosed dyslexia in adults. Getting assessed and support services can help adults better manage their dyslexia.
Are dyslexia and intelligence connected?
There is no connection between dyslexia and intelligence. Many people with dyslexia have average or above-average intelligence. Some signs of high intelligence include:
- Advanced vocabulary and conceptual knowledge
- Strong reasoning and critical thinking skills
- Creativity and out-of-the-box thinking
- Spatial skills and big picture focus
- Special talents in areas like art, athletics, music, mechanics, etc.
However, people with dyslexia often have weaknesses in rote learning, memorization, processing speed, and working memory. This makes tasks like reading, spelling, and math calculation slower and more difficult.
With the right support, people with dyslexia can develop strategies to bypass their challenges and leverage their strengths. Famous and successful people with dyslexia include scientist Albert Einstein, entrepreneur Richard Branson, and actress Whoopi Goldberg.
Does dyslexia go away?
No, dyslexia is a lifelong condition. However, the impact of dyslexia can be minimized through early diagnosis and evidence-based instruction. Here are some key points about dyslexia persistence:
- Dyslexia is a neurobiological condition, not something a child can overcome on their own.
- With effective reading instruction, children with dyslexia can make significant progress. However, reading, spelling, and writing will always be slower.
- Adults with dyslexia continue to read slower with less fluency. However, their vocabulary, reasoning, and listening comprehension skills can be very strong.
- Dyslexia is managed, not cured. People with dyslexia learn ways to work around and compensate for their challenges.
While dyslexia persists for life, with the right support most people with dyslexia can learn to read and succeed academically. The focus should be on finding the right learning environment and using strengths to bypass weaknesses.
Conclusion
In summary, research indicates that dyslexia is a neurobiological condition with genetic influences. The symptoms emerge in early childhood and persist throughout life. However, dyslexia occurs independently of intelligence or effort. With early assessment and evidence-based instruction, people with dyslexia can become skilled, independent readers.