Hyperlexia: Definition, Variant and Invariant Symptoms, and Possible Causes

Hyperlexia is a rare condition in which a child recognizes words (and can often spell them correctly) at a young age, but cannot comprehend what she reads. A child with hyperlexia seems to be reading precociously, but she cannot answer basic questions about what she has read. Some believe that hyperlexia is the opposite of dyslexia, at least neurologically. Many children with hyperlexia fall on the autistic spectrum, often exhibiting symptoms of Asperger syndrome.

There are several symptoms of hyperlexia that a child may exhibit as warning signs. Although some symptoms are invariant, meaning that they apply to all children with hyperlexia, others are variant, occurring only in some hyperlexic children. The following are invariant symptoms of hyperlexia:

· Extremely advanced skills in decoding; able to decode material far above what is expected for the child’s age level

· Acquisition of decoding skills spontaneously, without much instruction

· Severely underdeveloped comprehension skills; unable to comprehend at grade level or even slightly below

The following are variant symptoms of hyperlexia, many of which are similar to symptoms of Asperger syndrome, or other disorders on the autistic spectrum. Although some children with hyperlexia exhibit these symptoms, many do not:

· Rituals or other stereotyped behaviors

· Abnormal socialization skills; unable to interact easily with others

· Repetitive speech, sometimes resorting to echolalia

· Anxiety

· Other language problems

Although researchers are not sure what causes hyperlexia, there are some clues. When children with hyperlexia performed certain tasks, a MRI picked up addition activity in the left side of their brain, far more than what was found in the brain of a neurotypical child performing the same task. Psychologists refer to hyperlexia as a normal psychological variant, or a condition that comes from a difference in the child’s brain that came about during development. Although some believe that symptoms of hyperlexia can be caused by external factors, such as overwhelming parental pressure, reaction to a traumatic event, or other circumstances in the child’s life, most experts seem to disagree.