Scientists have found preliminary evidence that oxytocin, a brain chemical frequently dubbed the "love hormone" because of the critical role it plays both in sexual pleasure and giving birth, holds promise as a potential new treatment for autism.
"Those who received oxytocin seemed to do much better," said Evdokia Anagnostou, an autism researcher at Mount Sinai Medical Center in New York City.
While it is hardly implausible that a hormone involved in orgasm would have positive effects on anyone, these findings of improvement in adults with autism given oxytocin are based on measurable changes in behavior as well as visible changes in their brains as seen through functional magnetic resonance imaging.
"It's very preliminary data," cautioned Anagnostou, who spoke Thursday at the 6th International Meeting for Autism Research. The meeting, which has drawn about 900 scientists, physicians and others from around the world, is being held through Saturday at the Seattle Sheraton Hotel and Towers. It is not open to the public.
Previous studies have indicated that oxytocin, which also causes milk production in breastfeeding mothers, plays some role in how mammals manage fear, develop trust and establish socially cooperative behavior. Autism is a disorder in which, among other things, individuals have difficulty establishing social relationships.
Anagnostou and her colleagues at Mount Sinai, including group leader Eric Hollander, have been administering oxytocin intravenously and by a nasal mist to adults with autism spectrum disorders.
While the studies have been limited to a small number of people, she said those who received the hormone improved in their ability to identify emotions as described in writing to them and also reduced characteristic autistic repetitive behaviors. They maintained these observed improvements two weeks after exposure to oxytocin.
Brain imaging, Anagnostou said, also showed improvement in regions of the brain known to be involved in autism. The findings are very early, she said, but they may point to a possible new treatment for the disorder.
"It's promising, but we still need to do more study of this," Anagnostou said.
Also at the autism research meeting, University of Louisville neuroscientist Manuel Casanova spoke on how structural differences in the brain may help explain why some autistics suffer severe developmental disabilities while others -- though still suffering deficits -- demonstrate brilliance in mathematics, memorization or other manifestations of genius.
"It has to do with connectivity," Casanova said. He and some other scientists point to studies indicating that autism is basically the result of bad wiring in the brain. Though that doesn't get to the cause of what's making the brain go haywire, Casanova said an increasing body of evidence supports the theory.
At a news conference Thursday, he said that basic structural units of the brain's cortex known as "mini-columns" are overproduced and undersized in people with autism. That correlates, he noted, with the observation of hyperdevelopment of the brain in many children with autism disorders.
"In some cases, this eventually constrains development" Casanova said. Nerve fibers get pinched off, he said, and long-term connectivity in the brain is reduced. Short-term connections between nerves, however, are often enhanced. Where development ends up in the balance -- between the gain of many more cortical mini-columns and damage to long-term connectivity -- may make the difference between disability and genius savant, he said.
It appears that many people with autism develop "many more microprocessors than normal," Casanova said. Why this happens and where it may lead in terms of treatment or efforts to figure out the cause of autism, he said, is unknown.
"I believe it is the wiring of our brain, not so much any different portion of the brain, which makes us unique as a species," Casanova said. Studies of the wiring in autistic brains, he said, may lead to much better understanding of what it means to be human.
Eric Fombonne of Montreal Children's Hospital at McGill University also spoke at the news conference Thursday. Fombonne and his colleagues examined the hair and blood of autistic children for mercury and other heavy metals.
"There has been a scare about vaccines that contain mercury," he said. Fombonne explained that the evidence overwhelmingly indicates that trace mercury in vaccines is not harmful, but many parents are still concerned enough to justify continued examination of the possibility.
For the study, blood and hair samples were taken from more than 150 children -- half with autism and half not. The McGill scientists found no difference in the mercury levels between the two groups of children.
That, Fombonne said, is more evidence challenging the popular notion that vaccines cause autism. He noted that in Quebec, where the use of mercury-containing vaccines ended about a decade ago, there has been no decline in autism rates. Though some studies indicating some association between mercury and autism continue to be circulated, most other studies in credible scientific journals have failed to support the vaccine-autism link.
"It's clear there is no evidence of mercury poisoning in autism," Fombonne said
He added that some parents who don't believe the science are still subjecting their children to chelation therapy -- a chemical process by which heavy metals and minerals are removed from the body. That, he said, can be dangerous and sometimes even deadly.
"A child died as a result of chelation not too long ago," Fombonne said. It is important for parents to pay careful attention to the bulk of the scientific evidence, he said, and not potentially do harm to their children based simply on mistrust of the scientific establishment.
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