Onset and clinical course

No specific causes have been identified for autism and it is associated with a number of different disorders. Some parents report concerns from birth however in 15-40% of children with Autistic Disorder there is seemingly normal development for the first 15 to 19 months which is followed by a period of regression or loss of early vocabulary, reduced social interaction and responsiveness and sometimes an increase in repetitive play. Autistic Disorder cannot be cured as such and the deficits are thought to be lifelong but helped with training and education.  People who have an autism spectrum disorder with good communicative and intellectual functioning do best, however follow up studies suggest only a small percentage of   adults can work and most need varying levels of support.   A small number of individuals have special skills such as the ability to know vast amounts of   information about one subject or rote memory skills; however this does not usually help the person   function in an adaptive way. Lorna Wing, an English psychiatrist and the author of many books and academic papers on  autism, described three clinical sub-groups of autism. These describe the common types of  presentation of people with autism spectrum disorders:   • The aloof: this is the most commonly described type of social impairment. Individuals  appear to live in a world of their own and behave as if other people do not exist. They may  have little or no eye contact and no reponse when spoken to, and may have a limited and  unusual range of emotional expression;  • The passive: this is least commonly described. Individuals in this group may accept social  approaches albeit with indifference and will usually comply with requests made of them.  Questions are answered with complete honesty, whether that is socially appropriate or not.  They experience great difficulty with stress or change. • The “active but odd”: the individuals in this group make active approaches to others but  in unusual ways, such as appearing to pay no attention to the other person, poor or otherwise  discomforting eye contact or excessive physical contact, e.g. hugging or shaking hands too hard  or too long.