ABSTRACT
If there is consensus that autism is now understood to be a neurobiological condition, with associated genetic influences, there is still significant debate about why the brain in those with the condition might develop as it does. Is this something that is pre-determined in the womb, either as a question of inheritance or because of some event in utero? Or might it be connected to the ways that the brain grows and changes after birth, a process that might be organic or one that could be influenced by external factors? There are arguments that seem to supply evidence for a range of possibilities: genetic research suggests the importance of inheritance, while our understanding of the ways in which the brain develops during the first years of life points to the possibility that it might be during this period that the structures of the brain responsible for autism take their final form; and, in support of potential external causes, one of the mostrepeated observations about the development of autism in the very young is that the onset of the condition appears to happen suddenly around the age of two. Up to that point, some parents observe, their child displays no signs of autism and appears to be developing in line with other children. In these cases, autism appears to arrive unheralded, and it seems only natural to assume that there is some cause for the change, something that happens. It should be stressed that such opinions are usually anecdotal, and no research has given any indication of the commonality of this kind of onset of the condition, but it is a point of view made with some regularity by a number of parent groups.
