Symptoms of Asperger’s syndrome range from relatively mild to severe. In many cases, parents and physicians may be unaware of the problem early in a child’s life, as it is common for children with Asperger’s syndrome to exhibit normal to high levels of intelligence.

The first symptoms usually appear by age 3, although some children may exhibit signs as early as infancy. Developmental delays in motor skills (such as crawling, walking, catching a ball or pedaling a bike) or excessive clumsiness are sometimes the first signs of Asperger’s syndrome. Other symptoms of the condition typically become more apparent when the child reaches school age and begins regularly interacting with peers.

Children with Asperger’s syndrome may struggle to make friends and may talk for long periods of time without allowing others to contribute to the conversation. When communicating, these children may avoid eye contact and their faces may lack expression. They may speak in monotone, fast or unusual patterns. They also may engage in unusual body postures or gestures.

Other symptoms related to social skills include:

• Difficulty empathizing or being sensitive to others’ feelings
• Self-absorption
• Difficulty understanding the nuances of language
• Inability to interpret other peoples’ body language
• Hyperactivity and inattention

Children with Asperger’s syndrome may also exhibit unusual behavior patterns. It is very common for such children to become obsessed with a topic of interest, such as reciting sports statistics, or having an unusually strong fixation on a particular subject, such as the weather. In many cases, these topics may be unusual, such as excessive interest in aliens or bus routes.

Repetitive rituals and movements, the ability to memorize facts easily, clumsy or uncoordinated movements, rigid routines, violent outbursts (e.g., tantrums) and hypersensitivity to light and sound are all hallmarks of Asperger’s syndrome. Some patients with Asperger’s syndrome may also injure themselves.

Symptoms of Asperger’s syndrome may appear different depending on the patient’s age. For example, a child’s difficulties in social situations may not be as evident at first and may become more apparent over time. Adolescents with Asperger’s syndrome may learn to use areas of strength (such as memorization abilities) to overcome areas of weakness. On the other hand, adolescents may experience depression and anxiety as they become more aware of their disorder and their social isolation.