Infants may have a delayed or absent social smile. They may fail to interact with caregivers. They may not reach out to be picked up and held. Pleasure is not shown in cuddling or other contact. A lack of social interest is present as the child ages.
Repetitive behavior occurs in the child's second year.
Examples are flicking a light switch on and off, passing a toy back and forth from one hand to the other, or walking around a room feeling the walls. Common body movements might include hand flicking or twisting, spinning, or head-banging. Stopping these behaviors or disturbing their surroundings may cause the child to respond with a temper tantrum. Speech is not used for meaningful communication during the early childhood years. There is often constant and meaningless repeating of another's words or phrases.