Dyslexia affects the way that the brain processes written materials, making it more difficult to recognize, spell, and decode words.

The effects of dyslexia vary from person to person. People with the condition generally have trouble reading quickly and reading without making mistakes. They may also have trouble understanding what they read.

Dyslexia is a neurological issue, and it can run in families. It is not the result of poor teaching, instruction, or upbringing.

While it can be challenging, almost everyone with dyslexia can learn to read if they receive the right instruction.

Throughout early 2018, 33 legislative bills relating to dyslexia were introduced in the United States. This reflects the fact that government organizations are recognizing the need for early intervention to support children with dyslexia.

People with dyslexia are most likely to receive a diagnosis as children or young adults.

Adults who receive this diagnosis have usually had the condition their whole lives. However, a person can acquire dyslexia because of a brain injury.

If a parent, guardian, or teacher suspects that a young person has dyslexia, they should ask about a professional evaluation. The school may be able to help. An early diagnosis is more likely to lead to effective management.

Receiving a dyslexia diagnosis may open the door to more support for the child or adolescent. They may become eligible for special education services, support programs, and services in colleges and universities.

According to the International Dyslexia Association, diagnostic evaluations often cover the following areas:

• background information, including family history and early development
• intelligence
• oral language skills
• word recognition
• fluency skills
• reading comprehension
• vocabulary knowledge
• decoding, or the ability to read new words using letter-sound knowledge
• phonological processing, or how the brain processes the sounds of words

During the assessment, the examiner will aim to rule out other conditions that can have similar symptoms. Examples include vision problems, hearing impairment, a lack of instruction, and social and economic factors.

People can show symptoms of dyslexia at any age, but they tend to appear during childhood.

Dyslexia can cause challenges that involve:

Reaching development milestones

Children with dyslexia may learn to crawl, walk, talk, and ride a bicycle later than their peers.

Learning to speak

A child with dyslexia may take longer to learn to speak. They may also mispronounce words, find rhyming challenging, and appear not to distinguish between different word sounds.

Learning to read

This difficulty can present as early as in preschool. A child may find it difficult to match letters to sounds, and they may have trouble recognizing the sounds in words.

Dyslexia symptoms can also arise when young people start learning more complex skills. For example, the condition can cause difficulty with:

• grammar
• reading comprehension
• reading fluency
• sentence structure
• in-depth writing

Caregivers and teachers may notice that a child is reluctant to read — they may avoid situations that require it.

Learning to write

On paper, a person with dyslexia may reverse numbers and letters without realizing it.

Also, some children with dyslexia do not follow expected patterns of learning progression. For example, they may learn to spell a word and completely forget the next day.

Processing sounds

If a word has more than two syllables, processing the sounds can become much more challenging. For example, in the word “unfortunately,” a person with dyslexia may be able to process the sounds “un” and “ly,” but not those in between.

Sets of data

Children with dyslexia may take longer to learn the letters of the alphabet and how to pronounce them. They may also have trouble remembering the days of the week, months of the year, colors, and some arithmetic tables.

Coordination

A person with dyslexia may be less coordinated than their peers. For example, catching a ball may be difficult, and they may confuse left and right.

Reduced hand-eye coordination can also be a symptom of other, similar neurological conditions, including dyspraxia.

Concentration

People with dyslexia often find it hard to concentrate. This may be because, after a few minutes of struggling to read or write, they feel mentally exhausted.

Also, compared with the general population, a higher number of children with dyslexia also have attention deficit hyperactivity disorder (ADHD).

According to some estimates, 30% of those with dyslexia also have ADHD, compared with 3–5% of the general school population experiencing both conditions.

The sequence of ideas

A person with dyslexia may express ideas in a sequence that, to their peers, seems illogical or unconnected.

Autoimmune conditions

People with dyslexia are more likely to develop autoimmune conditions, such as seasonal allergies, asthma, and eczema.