Social Difficulties

• A child with classic autism may not respond to people and may avoid eye contact. He may be withdrawn and seem unable to play normally with other children.
  
  

Narrow Interests

• Children with classic autism may focus on one item for abnormally long periods of time, and be fixated on a very narrow range of objects and interests.
  
  

Inflexible Behavior

• An autistic child may be very inflexible about routines and engage in ritual behavior. For instance, she may insist on having a certain type of food at every meal. She is likely to become upset at changes in her environment.
  
  

Sensory Abnormalities

• Many children with classic autism are unusually sensitive to sensory stimulation, making them avoid or become upset at loud sounds, bright lights, or being hugged or touched.
  
  

Repetitive Actions

• Performing repetitive movements is a sign that a child has classic autism, such as rocking, flapping arms, or hitting himself over and over. The child also may use language in a very repetitive or sing-song manner.