Social interaction and communication
Social differences revolve around the give-and-take of normal social interactions, non-verbal social communication, and skills in developing, maintaining and understanding relationships.
Communication skills can vary greatly between children with ASD; some children may have little if any speech, while others may have well-developed language skills. However, those that do have language skills often find it difficult to communicate effectively. They may say odd or inappropriate things, make blunt or impolite comments, talk about a specific topic for long periods of time with no awareness that others have lost interest, or say things that are not relevant to the current conversation.
Differences with non-verbal communication include difficulty in making and maintaining eye contact, and understanding non-verbal communication of others such as facial expressions and hand gestures such as pointing.
Some people with ASD seem quite aloof or detached from others, but this is not the case for all people with ASD, with some being quite affectionate and fond of company. People with ASD do often tune out when others are talking to them, or appear not to listen, especially when the conversation does not involve their favourite topic of interest.
Behaviour and interests
People with ASD can have a very narrow or unusual set of interests, or they may play in a repetitive way. They may know everything about a certain topic and talk about it constantly, want to watch the same television show over and over, or focus their play on a single toy.
They often show limited imaginative play, but may use toys and other objects in unusual ways, such as lining up objects, focusing on the spin on the wheel of a toy car, or watching the light shine off various things. Some children with ASD engage in unusual behaviours, such as hand-flapping or rocking, which is usually a sign of excitement or agitation. Many experience difficulties coping with change, but do better when they are prepared ahead of time for changes in routine.