Dyslexia is a common language learning disorder that interferes with a person’s ability to read and write fluently. It’s not known exactly what causes dyslexia, but it is known to run in families.
Children and adults who have dyslexia have been found to struggle with:
- phonological awareness (the knowledge of how speech sounds correspond to letters/symbols)
- verbal memory (the ability to hold several words in memory)
- rapid verbal processing (the ability to quickly recognize and understand verbal letters, numbers, words, or instructions)
- rapid serial naming (the ability to rapidly categorize and name similar objects)
It is important to recognize that dyslexia is specific to certain language-based skills and is not in any way indicative of overall intelligence.
Specialized reading education with a trained reading instructor or speech-language pathologist can help to unlock a person’s potential in terms of effective, fluent reading and writing skills.
Genetic and Neurological Factors
It is known that dyslexia runs in families and is often present in both siblings among sets of twins. To date, six specific genes have been identified as potentially contributing to dyslexia.
In addition to genetics, brain imaging studies have found differences in the neurological functioning of some individuals with dyslexia. It is thought that these genetic and neurological factors contribute to dyslexia.
Phonological processing is the ability to match a symbol, such as a letter, to a speech sound. Each word contains multiple speech sounds called phonemes. For example, the word “bat” has three phonemes: ‘b,’ ‘a,’ and ‘t.’ The word “mat” also has three phonemes and is different from “bat” in only one phoneme (‘m’ rather than ‘b’).
In speech, it is not necessary to break a word into its individual phonemes. In reading and writing, however, a person must learn to recognize the phonemes in each word and to correctly match them to the corresponding symbols. It is believed that this is the skill that is impaired in individuals who have dyslexia.Symptoms of dyslexia vary widely from person to person. They can also be different within the same person as he or she ages.
Dyslexia in Preschool-Aged Children
Symptoms of dyslexia in young children include:
- speech development delays
- repeated difficulty with saying or learning long or complex words
- difficulty choosing the correct word
- difficulty constructing longer sentences
- difficulty understanding multi-step directions (for example, “get your coat and put on your shoes”)
- disinterest in rhymes or letters
Dyslexia in Older Children
Children often begin to show signs of dyslexia either when reading instruction begins, or at around grade four when the focus of education shifts from “learning to read” to “reading to learn.”
Symptoms at these ages can include:
- difficulty learning the alphabet or the sounds that correspond to the letters
- difficulty learning handwriting
- confusion about the order of letters in words
- confusion about letters that appear similar, such as ‘n’ and ‘m’
- unusual, incorrect, or unpredictable spelling
- difficulty focusing on words (words appear blurry or seem to move on the page)
- verbal skills that are more advanced than reading and writing skills
- difficulty with sequences, such as sequential directions or naming things in order
- slow, laborious reading when reading aloud
- slow, laborious writing and copying
- difficulty with recognizing rhyming or thinking of rhyming words
- difficulty manipulating sounds in words (for example, naming the number of speech sounds in “mat,” or figuring out what word is made when switching a ‘b’ for the ‘m’ in “mat”)
- sounding out words
- reading new words for the first time
Dyslexia in Teenagers and Adults
In addition to the symptoms of dyslexia seen in children, older individuals often show symptoms that reflect the increased complexity of the texts they are expected to read and write.
Symptoms of dyslexia that can appear in teens and adults include:
- impaired spelling
- difficulty taking notes or studying
- difficulty organizing narratives in writing despite the ability to demonstrate knowledge aloud
- difficulty remembering sequences of letters or words, such as a password
- avoiding reading and text. Source