Autism.

Today half a million people across the UK are considered to be autistic, 50 years ago the condition was thought to affect only 1 per 1000 of the population. Is this increase in numbers due to there being more autistic people or is it the diagnostic criteria that have changed? Other questions Mark Porter approaches are why is autism four times more common in boys? Do testosterone levels play a role in autism? What hopes are there in the future for the treatment or even prevention of autism? We hear from members of the medical profession and a mother of a young autistic boy tells about how she embarked on an intensive period of behavioural therapy in her own mother's converted bedroom.