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PICTURES - Is it autism? Facial features that show disorder
For the small study, scientists examined the brains of seven autistic children and six children without autism, all of whom had died by drowning or other causes between the ages of two and 16. The researchers found that the autistic kids had 67 percent more brain cells (neurons) in the prefrontal cortex. That's the brain region just behind the forehead.
In addition to more neurons - about 1.9 billion vs. about 1.2 billion for the control children - the brains of the autistic children weighed more.
What does it all mean?
Study author Dr. Eric Courchesne, director of the National Institute of Health-University of California-San Diego School of Medicine Autism Center of Excellence, told WebMD that the research was "a small study with a large impact. The extra neurons mean "a huge increase in potential connections and, therefore, a potential for 'miswiring' which would lead to abnormal function," he told HealthDay.
The study - published in the Nov. 9 issue of the Journal of the American Medical Association - seems to go against the belief that autism is the result of vaccines administered in early childhood. Dr. Lizbeth Romanski, of the University of Rochester Medical Center in New York, told HealthDay that neurons are created during the second trimester. "That is when these neurons are being born," she said. Dr. Romanski was not involved in the study.
Because the extra neurons can be measured by a brain scan, the new study could point to new ways to clarify a diagnosis of autism, according to WebMD. Currently, the condition is diagnosed on the basis of symptoms and behaviors, not blood tests, brain scans, or other more tangible indicators.
In the meantime, concerned parents should be on the lookout for worrisome symptoms - problems with speech, in particular.
"The hallmark of autism is language delay," Los Angeles-based pediatrician Dr. Y. Jane Tavyev Asher told WebMD. "So if there is early language delay, shoot first and ask questions later. It's better to have started a little speech therapy and find out it's not autism than to go from person to person being evaluated before starting speech."
In addition to communication problems, autism can affect social interaction, intelligence, and behavior. It affects about one of every 110 children.
The CDC has more on autism spectrum disorders.
Wouldn't that be ignoring the fact that autism has been around before the 1930s or that fraudulent claim that the children were developing normally has been exposed years ago?
W&N
Neuronal Organization & Head Circumference: Several autism brain studies have found evidence of increased neuronal cell replication, a lowered ratio of glia to neurons, and an increased number of glial cells (Bailey et al, 1996). Based on these and other neuropathological findings, autism can be characterized as "a disorder of neuronal organization, that is, the development of the dendritic tree, synaptogenesis, and the development of the complex connectivity within and between brain regions" (Minshew, 1996).
Rat pups dosed postnatally with methylmercury had significant reductions in neural cell adhesion molecules (NCAMs), which are critical during neurodevelopment for proper synaptic structuring. Sensitivity of NCAMs to methylmercury decreased as the developmental age of the rats increased. "Toxic perturbation of the developmentally-regulated expression of NCAMs during brain formation may disturb the stereotypic formation of neuronal contacts and could contribute to the behavioral and morphological disturbances observed following methylmercury poisoning" (Deyab et al, 1999). Plioplys et al (1990) have found depressed expression of NCAM serum fragments in autism.
Abnormalities in neuronal growth during development are implicated in head size differences found in both autism and mercury poisoning. In autism, Fombonne and colleagues (1999) have found a subset of subjects with macrocephaly and a subset with microcephaly. The circumference abnormalities were progressive, so that, while micro- and macrocephaly were present in 6% and 9% respectively of children under 5 years, among those age 10-16 years, the rates had increased to 39% and 24% respectively. Another study, by Stevenson et al (1997), had
Neuronal Organization & Head Circumference: Several autism brain studies have found evidence of increased neuronal cell replication, a lowered ratio of glia to neurons, and an increased number of glial cells (Bailey et al, 1996). Based on these and other neuropathological findings, autism can be characterized as "a disorder of neuronal organization, that is, the development of the dendritic tree, synaptogenesis, and the development of the complex connectivity within and between brain regions" (Minshew, 1996).
Mercury can interfere with neuronal migration and depress cell division in the developing brain. Post-mortem brain tissue studies of exposed Japanese and Iraqi infants revealed "abnormal neuronal cytoarchitecture characterized by ectopic cells and disorganization of cellular layers" (EPA, 1997, p.3-86; Clarkson, 1997). Developmental neurtoxicity of Hg may also be due to binding of mercury to sulfhydryl-rich tubulin, a component of microtubules (Pendergrass et al, 1997). Intact microtubules are necessary for proper cell migration and cell division (EPA, review, 1997, p.32-88).
Abnormalities in neuronal growth during development are implicated in head size differences found in both autism and mercury poisoning. In autism, Fombonne and colleagues (1999) have found a subset of subjects with macrocephaly and a subset with microcephaly. The circumference abnormalities were progressive, so that, while micro- and macrocephaly were present in 6% and 9% respectively of children under 5 years, among those age 10-16 years, the rates had increased to 39% and 24% respectively. Another study, by Stevenson et al (1997), had found just one subject out of 18 with macrocephaly who had this abnormality present at birth. The macrocephaly in autism is generally believed to result from "increased neuronal growth or decreased neuronal pruning."
They are measuring events that occur during embryonic development--not post-birth pruning.
W&N
This study says nothing about the cause of autism--which cannot be genetic because there is no such thing as a genetic epidemic. 13 children in a study says nothing--it's a teeney, tiny, tiny study(way too small) to have significance. What about children with extra neurons that don't have autism-again nada on this because the study is too tiny. Waht about children with extra neurons that don't have autism? Again, huh? The only thing the study might tell us is that some children might have a predisposition before birth with excessive neurons to be vulnerable following birth to excessive environmental toxins like vaccines.
I don't think these authors of the study should break out the chianti yet, but it is a good try to point the direction away from vaccines again for the greater masses. Bravo for the effort.
Maurine Meleck, SC
As far as Dr. David Amaral is concerned, he says there is no difference in autism rates between vaccinated and never vaccinated children. He knows full well no such study exists. He seems to have his own agenda regarding the cause of autism and wants the focus off of vaccines.
Please explain how "residual, human DNA" injected into the muscle of the thigh passes the blood brain barrier to affect the development of the brain.
This is simple. Injection in the thigh feeds the capillaries and provides rapid access to the blood-stream. This is the purpose of injection. Once in the blood of an infants, it easilly permetates the imature blood-brain-barrier.
Amaral referred to the work that Dr. Eric Courchesne discussed in his keynote address at the meeting, in which Courchesne asserted that in ASD the evidence "points strongly to dysregulation of functions that govern [brain development] in the second trimester . . . to very early events that are driving the failure of the normal organization of the brain . . . All these things are being driven by events that are prenatal . . . because there are no known mechanisms for producing such a gigantic difference [a 25% to 65% excess in the frontal cortex] in neuron numbers postnatally in the human brain."