Two new studies out of the University of Washington's Autism Center say accelerated head growth can help pediatricians predict autism before behavioral symptoms start. According to the research, children later diagnosed with autism have normal-size heads at birth, but show accelerated head growth between six and nine months of age. The center says that this period precedes the onset of many behaviors that enable physicians to diagnose the developmental disorder. The study also indicates that this aberrant growth is present in children who have the early onset form of autism as well as those later diagnosed with the regressive type of the disorder, suggesting that an atypical biological process was in place before the regression occurred. Dr. Geraldine Dawson, one of the authors of the studies and now the Chief Science Officer at Autism Speaks, points out that "many typically developing children will also have larger than normal heads, so accelerated head growth doesn't lead to a higher risk for autism. However, accelerated head growth in an infant sibling of a child with autism, who is at higher risk for the disorder, should be monitored closely."