Introduction

Some children are less socially interactive and communicative than others. When the combination of social and communication problems takes on the quality of a clinically severely impairing condition one needs to consider the possibility of a disorder of social interaction, particularly one that may fall under the diagnostic umbrella of ‘autism spectrum disorders’.

Autism was first delineated as a syndrome of childhood onset by Leo Kanner in the US in the 1940s. Long before that – at the turn of the eighteenth century – classic autism cases had been described by John Haslam in the UK and Jean Itard in France. The word autism (from the Greek autos for self) was introduced by Eugen Bleuler to depict the self-centred thinking believed to be typical of schizophrenia. Considered by Kanner to be a discrete disease entity, early infantile autism was conceptualized as an extremely rare disorder, and one which would be easy to identify and diagnose. It was only in the early 1980s that the concept of autism spectrum disorder was introduced by Wing and Gillberg. Wing put forward the notion of a fairly specific triad of impairments of social, communicative and imaginative functioning as being at the basis of all autism spectrum disorders. She also coined the term Asperger's syndrome for the kind of ‘high-functioning’ autism spectrum disorder described originally by Hans Asperger (who used the term autistic psychopathy) at about the same time that Kanner described his more ‘low-functioning’ variant of autism.