A symptom is something the patient senses and describes, while a sign is something other people, such as the doctor notice. For example, drowsiness may be a symptom while dilated pupils may be a sign.

The Dyslexia Research Trust includes these as the most common signs and symptoms associated with dyslexia:

Learning to read
the child, despite having normal intelligence and receiving proper teaching and parental support, has difficulty learning to read

Milestones reached later
the child learns to crawl, walk, talk, throw or catch things, ride a bicycle later than the majority of other kids


apart from being slow to learn to speak, the child commonly mispronounces words, finds rhyming extremely challenging, and does not appear to distinguish between different word sounds

Slow at learning sets of data
at school the child takes much longer than the other children to learn the letters of the alphabet and how they are pronounced. There may also be problems remembering the days of the week, months of the year, colors, and some arithmetic tables

the child may seem clumsier than his or her peers. Catching a ball may be difficult

Left and right
the child commonly gets "left" and "right" mixed up

numbers and letters may be reversed without realizing

may not follow a pattern of progression seen in other children. The child may learn how to spell a word today, and completely forget the next day. One word may be spelt in a variety of ways on the same page

Phonology problems
phonology refers to the speech sounds in a language. If a word has more than two syllables, phonology processing becomes much more difficult. For example, with the word "unfortunately" a person with dyslexia may be able to process the sounds "un" and "ly," but not the ones in between

Concentration span
children with dyslexia commonly find it hard to concentrate for long, compared to other children. Many adults with dyslexia say this is because after a few minutes of non-stop struggling, the child is mentally exhausted. A higher number of children with dyslexia also have ADHD (attention-deficit hyperactivity disorder), compared to the rest of the population

Sequencing ideas
when a person with dyslexia expresses a sequence of ideas, they may seem illogical for people without the condition

Autoimmune conditions
people with dyslexia are more likely to develop immunological problems, such as hay fever, asthma, eczema, and other allergies.