The characteristics of children and young people with ASD will vary depending upon their age, developmental level and how severely they are affected.
The difficulties are also likely to change over time. Parents are usually (but not always) the first to have some concerns about their child’s development, and difficulties may be noticed from as early as infancy. Overall, the problems and behaviours can be divided into three main areas:
Difficulties with communication
Children and young people with ASD have difficulties with both verbal communication (speaking) and non-verbal communication (eye contact, expressions and gestures). Some children may not be able to talk at all or have very limited speech.
Some have good speech and language skills, but still have difficulty using their speech socially or to sustain a conversation. Their use of language may be overly formal or 'adult-like'. They may talk at length about their own topics of interest, but find it hard to understand the back and forth nature of two-way conversations.
Difficulties with social interaction
Children and young people with ASD have difficulty understanding the 'social world', for example, they often have difficulty recognising and understanding their feelings and those of people around them. This in turn can make it difficult for them to make friends. They may prefer to spend time alone, or appear insensitive to others because of their difficulties understanding social rules and expectations.
Difficulties with behaviour, interests and activities
Children and young people with ASD often prefer familiar routines (e.g. taking the same route to school every day, putting their clothes on in a particular order), and tend to have difficulties dealing with change, which they find difficult and distressing.
They may also have unusual intense and specific interests, such as in electronic gadgets or lists of dates. They might use toys more like 'objects' to line up, for example. They may have unusual responses to particular experiences from their environment such as tastes, smells, sounds and textures. For example, they could be very sensitive to the sound of a hair dryer, or the feel of certain materials against their skin.
Some children show unusual repetitive movements such as hand or finger flapping or twisting, or complicated whole body movements.