Hyperlexic children are often fascinated by letters and numbers. They are extremely good at decoding language and thus often become very early readers. Some hyperlexic children learn to spell long words (such as elephant) before they are two and learn to read whole sentences before they turn three. An fMRI study of a single child showed that hyperlexia may be the neurological opposite of dyslexia.
Often, hyperlexic children will have a precocious ability to read but will learn to speak only by rote and heavy repetition, and may also have difficulty learning the rules of language from examples or from trial and error, which may result in social problems.
Despite hyperlexic children's precocious reading ability, they may struggle to communicate. Their language may develop using echolalia, often repeating words and sentences. Often, the child has a large vocabulary and can identify many objects and pictures, but cannot put their language skills to good use. Spontaneous language is lacking and their pragmatic speech is delayed. Hyperlexic children often struggle with Who? What? Where? Why? and How? questions. Between the ages of 4 and 5 many children make great strides in communicating.
Social skills often lag tremendously. Hyperlexic children often have far less interest in playing with other children than do their peers.