Many people are unsure about the differential diagnosis of disorders such as autism, ADHD and Asperger Syndrome, and this can lead to confusion and upset. We wanted to clear up some of the confusion with a very brief summary of the most commonly talked-about disorders and how they differ from each other.
Autism and Autism Spectrum Disorder (ASD) are both general terms for a group of complex disorders of brain development. These disorders are characterized, in varying degrees, by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviours. Autism is a lifelong, developmental disability that affects how a person communicates with and relates to other people, and how they experience the world around them
Asperger Syndrome – This disorder is part of the autistic spectrum and is characterized by difficulties in communication and interaction. This diagnosis is used for people who have good grammatical language but use it mainly to talk about their special interests.
Attention Deficit Hyperactivity Disorder (ADHD) – A developmental disorder that is not part of the autism spectrum disorder but can occur alongside the autism spectrum disorder. ADHD is characterized by poor attention span together with marked overactivity.
Attention Deficit Disorder (ADD) – A developmental disorder that is not part of the autism spectrum disorder but can occur alongside the autism spectrum disorder. ADD is characterized by poor attention span without marked overactivity.
It is important to note that the symptoms of Autism Spectrum Disorder (ASD), ADD and ADHD can overlap – for example, a child with autism may also have issues with attention and hyperactivity.
For more detailed information on differential diagnosis between a wide range of disorders this page is very helpful: http://www.autism.org.uk/labels