Autism Speaks to the World, an International Congress for Autism Research, hosted by Autism Speaks and the Mexican Autism Clinic, A.C. (CLIMA) continued on July 6 at the Royal Pedregal Hotel in Mexico City. Ongoing from June 5-7, 2007, the Congress will promote awareness, treatment services, and autism research throughout Mexico and the world. For a live web cast of the conference, log onto http://www.autismcongress.org from 10:30 a.m. to 7:30 p.m. EDT on Saturday, July 7.
Speakers during day two of the Autism Speaks to the World congress addressed a range of issues surrounding the diagnosis, assessment, and treatment of autism, focusing particularly on research developments in infants and toddlers. (For a recap of day one, click here.)
Geraldine Dawson, director of the University of Washington Autism Center, known worldwide for her pioneering work on early diagnosis and brain function in autism, said early signs of the disorder can emerge as early as six months. Data obtained from home videos show babies with autism at that age don't respond to their names, nor do they make eye contact, or respond socially with those who attempt interaction. As babies with autism mature, social deficits can be accompanied by changes in brain structure and function, she added. For instance, by the age of three, the brains of children with autism are often larger compared to those without the disorder. Using an emerging technique called “EEG coherence” Dawson showed that brain regions of children with autism reveal that they are poorly synchronized, which might explain why they have difficulty with complex behaviors. Dawson described newer brain imaging studies focused on the “mirror neuron systems,” which are involved in imitation and become activated when others perform behaviors that the self also performs. “Mirror neurons allow the brain to map what we see others doing to our own behavior,” Dawson explained. “And the function of those neurons in children with autism is reduced.” Dawson concluded by describing part of her STAART (Studies to Advance Autism Research and Treatment) project, a center of excellence funded by the National Institutes of Health in the US, under which she will conduct randomized control interventions for children with autism 18 to 24 months of age. Ideally, behavioral methods developed by this group will affect brain circuitry in positive ways, by facilitating early social engagement and attention, she said.
Peter Szatmari, who holds the chair in child psychiatry at McMaster University, agreed that babies can exhibit autistic behavior, but he highlighted the limited ability of diagnostic tools to assess children at young ages accurately. For example, the Autism Diagnostic Observation Schedule (ADOS), he said, both over-diagnose due to lack of specificity and under-diagnose due to lack of sensitivity, those toddlers assessed at 18 months of age by roughly 30 percent. Szatmari stated that initial signs of autism observed at 12 months in children with the disorder typically stabilize by 18 months. He also spoke to a phenomenon called regression – which is a loss of abilities, primarily language, at the age of roughly 12 to 24 months among children who previously appeared normal. Dawson's home video studies suggest that regression might occur when autism susceptibility genes come into play as an infant matures, Szatmari suggested. Thus, normal rates of social and cognitive development appear to decline, leading to characteristic symptoms later. The Autism Genome Project, which Szatmari described as a “consortium of consortia,” may ultimately offer insights into these genetic mechanisms, he said. Possibly, genetic progress could yield blood tests for autism, he suggested, and provide opportunities to treat the disease using existing pharamacology. But Szatmari stopped short of advocating for routine infant screening based on so-called “prodromal,” or preliminary symptoms. Good screening tools for infants don't currently exist, he said, nor do effective treatments for these age groups.
Joseph Piven, professor of psychiatry at the University of North Carolina, presented additional data to support the data confirming increased brain size in children with autism. Piven oversees a longitudinal study of brain volume and employs a technique called magnetic resonance imaging. His studies show that infants with autism assessed at 12 months have enlarged heads, which correspond to a general increase in both gray and white matter in the brain. The jury's out on whether that increase causes autism, or is caused by it, he said. But he added that initial studies suggest larger brain volumes might result from an overgrowth of neuronal processes at young ages. Piven also cited research showing that children who harbor two pairs of the short serotonin transporter gene – which is a gene variation implicated in other mental disorders including depression, bipolar disorder, and schizophrenia – also tend to have larger brain volume, suggesting a possible link to autism. Humberto Nicolini, professor of genomics at the Autonomous University in Mexico City, said his research also implicates the serotonin transporter gene in the context of genetic variation.
A remarkable finding, Piven added, is that the brains of children who have both autism and a similar neurodevelopmental disorder called “fragile X” are more similar than the brains of children who have autism, but who do not have fragile X, suggesting that while the two disorders may have similar autistic presentations, they have different underlying neuropathology.
Victor Ruggieri, the chief of pediatric neurology at Buenos Aires British Hospital, emphasized that parents and pediatricians throughout Argentina and Latin America must become more aware of the early signs of autism. Ruggieri collected data for a prospective study of 100 children with autism, all of them recruited when their parents brought them to the hospital for unrelated reasons. Children less than one year old were typically brought in for co-morbidities, he said, such as seizures. Older children were brought in for behavioral problems. “The signs of autism are subtle [at younger ages] and so few people know how to detect them,” he said.
Current options for treatment were evaluated by Samuel Odom, director of the Frank Porter Graham Child Development Institute at the University of North Carolina. Odom performed meta-analyses of two complimentary methods of treatment: focused interventions and comprehensive treatments. The former, he explained, comprises a one-on-one approach between a teacher or clinician and a child with autism. Through his research, more than 2000 studies describing focused interventions were screened, ultimately generating 108 studies for inclusion. Most generated positive effect sizes. Comprehensive treatment methods are being subjected to meta-analysis now. Odom stressed the need for new treatment models that target infants and toddlers like those funded by Autism Speaks late last year. He also referred to a brand new research effort that will create 27 modules for evidence-based autism intervention, which will be available online at the Porter Graham Child Development Institute's website next year.
A fundamental conclusion from Day Two of the Congress is that autism emerges during a period of time when infant and childhood brain circuitry can still be altered, in many ways influencing the severity of the disease, or even its onset. But most children aren't identified until after that critical window. Future research will have to focus on early detection and intervention during these critical windows of brain development.