My son had a big head. Friends would comment on it. I thought he was adorable. He has 'grown' into it as he gets older. No one knows why but I think there is something to it. Big heads and autism.
My daughter has a big head. But so do I and my husband. Before jumping the gun, maybe you could measure your own heads? It might provide a hint. It could just be inherited.
My daughter has NF1-- neurofibromatosis. It's also associated with having a big head. It's susepcted that NF1 can contribue to autism.
Study: Increased brain size may be a predictor of autism
In a recent study, researchers at the University of California, San Diego found that the clinical onset of autism may be preceded by a smaller than normal head size at birth, followed by a sudden and excessive (which the researchers termed explosive) increase in head size between 1 to 2 months and 6 to 14 months. In this study head size (circumference) was measured by a tape measure. They concluded that an abnormally accelerated rate of growth may serve as an early warning signal for autism.
The head size of Autistic children at birth was found to be in the lower 25% when compared with heads of normal children and that the heads of Autistic children grew explosively large during infancy (to the 84th percentile on average - with mildly autistic subjects in about the 59th percentile and severely autistic children at or above the 97th percentile). Only 6% of the healthy infants showed accelerated growth compared with 59% of infants with autistic disorder. This increase by the end of the first year was strongly correlated with greater cerebral and cerebellar volumes by 2 to 5 years of age. These results suggest that growth dysregulation in 2 major cortices and underlying white matter in the brain underlies the increase in head circumference.
The researchers comment: "The brain volume increases could also reflect either aberrant compensatory responses to adverse prenatal conditions or deviant biological mechanisms that are first expressed in early postnatal life. Events and conditions, such as measles, mumps, and rubella vaccinations, childhood exposure to environmental toxins or pathogens, or unusual gastrointestinal or allergic reactions to food, that occur after the overgrowth are not logically plausible as causes. Although some may argue that such later occurring events might be important as aggravating factors."
There seems to be a correlation between large head at a certain age during toddlerhood and the later development of autism symptoms. Doctors would like to use head circumference as a predictor. I don't think it's all that accurate, but it can be ONE of the factors. I no longer have all the info, but you might be able to find articles on it if you google "autism head circumference." http://www.autism-pdd.net/forum/search.asp?KW=head+size& SM=1&SI=TC&FM=1&OB=1 Daniel is a small kid. It took longer for his soft spots to close though.Does anyone have good info...or stories about head circumference as related to ASDs? I know that there have been some studies published linking the two--but Im not sure if the info is valid.
Im worrying(of course) b/c my 4 yo has a diagnosis of pdd-nos(super high functioning)--and my one year old just had his measurements done--he is 25th percentile height and weight-and 75th percentile head circumference. The ped said I shoudnt worry b/c the percentiles have been consistant since birth and im not sure if thats accurate.
and by the way--my one year old just started EI due to low tone and strange gross motor patterns(bearing weight on the tops of his feet, curled toes in standing, etc)--but as of yet has no red flags for austism(good eye contact, good joint attention, etc)
Thanks for any input you have!!
Jen