Although the neurobiology of autism has been studied for more than two decades, the majority of studies have examined brain anatomy 10 or more years after the onset of clinical symptoms. The early neural defects that cause autism remain unknown, but their signature is likely to be most evident during the first years of life when clinical symptoms are emerging. In this lecture, Eric Courchesne (UC San Diego) highlights several new findings about the neural and genomic abnormalities in autism at young ages. (#24819)