Autism Spectrum Disorder (Children's Hospital of Philadelphia)

Autism spectrum disorder (ASD) is a complex neurological and developmental condition that usually appears during the first three years of life. Symptoms can range from mild to severe and vary with each individual. For instance, some children may rarely use words to communicate, while others may hold extensive conversations and use rich language. Some children may not like to be hugged or touched, while others seek out and enjoy physical touch.