Growing Neurobiological Links to Genetics, Environment and Behaviour

Autism Spectrum Disorders-A Rapidly Increasing Problem of Western Society: Autism comprises a spectrum of severe neurodevelopmental disorders of increasing incidence characterized by profound language impairment, impaired socialization, repetitive motor behaviour, sensory disturbances, severely restricted interests and self injury. There is also a high association with seizure disorder. Autism's prevalence, initially thought to be between 7 and 20 per 10,000, may now be greater than 1 in 150, an observation that cannot solely be accounted for by increased surveillance. Autism may co-exist with a number of neuropsychiatric conditions, including pervasive developmental delay, Asperger syndrome, fetal alcohol syndrome, thalidomide and valproate exposure, and a number of known genetic conditions. Remarkably, both classic neurological activities and gross brain function in most autistics are relatively intact, and in approximately 5 to 10% of documented cases, there is an idiosyncratic hypercompetancy in some aspects of visual spatial, acoustic, computational and artistic behaviour. Autism is more common in males. Researchers such as Simon BaronCohen at Cambridge University have suggested that prenatal exposure to sex hormones may play a role. Cohen suggests that autism may result from a hyper masculine brain that is more suited to processing objects, as opposed to a feminized brain, superior to processing facial expression.