In this study, the differences between the typically developing and ASD children were most striking for that time interval in which multisensory stimuli is normally processed. "We saw robust MSI in the typically developing kids from 100 and 200 ms after sensory stimulation reached the brain's cortex," said Dr. Foxe. "But in the ASD kids, MSI occurred significantly later—at about 310 ms—and at a much lower level."
"This doesn't mean that the children with ASD didn't integrate the information at all," he added. "It does mean that they didn't integrate it as effectively as they should have, given their age and maturity. They may go on to integrate well later in life. We don't know. This is a single slice of the developmental trajectory."
"This was a much-needed study of multisensory integration in autism," said Barry E. Stein, Ph.D., professor and chair of neurobiology & anatomy at Wake Forest University School of Medicine, who was not involved in the Einstein study. "Using simple logic and standard techniques for electrically mapping the brain, the authors have identified defects in the way ASD individuals synthesize cues from different senses. In doing so, they have not only helped confirm the insights of parents and clinicians, but they've improved our understanding of how the behavioral differences in children with ASD may result from sensory anomalies."
"Today, there's a cottage industry—actually more like a military-industrial complex— for multisensory integration therapies for children with autism," said Dr. Foxe. "A lot of parents' hard-earned cash goes into these interventions, all in the absence of actual empirical evidence that there is anything wrong with MSI in these children or that these therapies do any good."
The researchers are currently evaluating MSI in children from 6 years of age through early adulthood to better understand the developmental trajectory of multisensory integration. They also plan to study MSI in lower-functioning ASD children. "This experimental paradigm is especially good for that, because it makes so little demand on the kids," said Dr. Foxe. "As you can imagine, asking them to do tasks doesn't work very well."
Sophie Molholm, Ph.D., discusses her new study of how children with autism spectrum disorders process sensory information such as sound, touch and vision. Dr. Molholm is associate professor in the Dominick P. Purpura Department of Neuroscience and of pediatrics.
(Photo Credit: Courtesy of Albert Einstein College of Medicine)
An EEG cap is used to measure the brain's response to sensory stimuli.
(Photo Credit: Photo : Courtesy of Albert Einstein College of Medicine)