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Infant Brain Imaging Study (IBIS)



Past studies have indicated that siblings of individuals with autism are at a higher risk to develop autism themselves.1 The Infant Brain Imaging Study (IBIS) focuses on the brain development of younger siblings of children with autism spectrum disorder (ASD). By observing their progression researchers will be able to determine how normally developing brains and those affected by ASD differentiate in the infant stages of life.2 The IBIS will utilize results from MRI imaging and behavioral assessments conducted during each clinical visit to collect data on the progression of the children’s development at 6, 12, and 24 months of age.2-3 Magnetic Resonance Imaging (MRI) allows for researchers to view inside the body without the use of X-rays or radiation.4 The process can produce two- and three-dimensional images4 and is completely safe for people of all ages.3 According to the IBIS website, the goal of the IBIS is “to increase our understanding of the timing and pattern of brain development in very young children with autism. This knowledge will help us to understand the underlying causes and brain mechanisms involved in autism and the relationship of those brain mechanisms to particular behaviors and psychological processes.”2



The IBIS study hopes to further past research that has demonstrated both brain overgrowth and the arrival of the social symptoms often attributed to autism occur at around the end of a child’s first year of life.5 In 2003, Dr. Courchesne found evidence that after several months of life “head size increased from the 25th percentile based on the CDC averages of healthy infants to the 84th percentile in 6 to 14 months.”6 The IBIS study has already begun to release some of their own results regarding brain development in infants. In 2012, a study headed by Joe Piven, M.D., the Principal Investigator of the IBIS, “found clear differences in brain communication pathways as early as 6 months and continuing through 2 years of age in children who were later diagnosed with autism spectrum disorder (ASD).”7 The study was conducted on 92-high risk siblings, of which 28 met the criteria for ASDs at 24 months of age.8 These individuals demonstrated abnormal development of white matter fiber tracts by 6 months of age.9 This breakthrough discovery reveals that “before the emergence of behavioral symptoms, the neural networks that connect different brain regions are not developing normally in infant siblings who go on to develop autism.”9 According to Geri Dawson, Autism Speaks’ Chief Science Officer9, the implications of this study are two-fold:


  • The evidence helps researchers to understand why complex behaviors, such as social interactions, may be difficult for individuals with autism, because these behaviors require the coordination of many brain systems.

  • The results could serve as evidence that potential “biomarkers” could be found via imaging, this would allow doctors to identify the risk of ASD before the behavioral symptoms appear. Like other neurological conditions, such as Alzheimer’s disease and Parkinson’s disease, early biomarkers can indicate those at risk and allow for treatment to start before the symptoms are visible.


The latter implication is especially important because research has shown that the earlier the intervention occurs, the greater chance the individual has at reducing, or even preventing entirely, the symptoms of autism.10 The sample size of this study is only a fraction of the IBIS’ overall goal. In the long-term, the IBIS hopes to monitor and analyze brain development of 544 siblings of children with autism5 and 150 low risk infants.11



In 2010, the Infant Brain Imaging Study expanded its scope to include infants with siblings diagnosed with Fragile X Syndrome (FXS). The study’s expansion was made possible through new funding from the Eunice Kennedy Shriver National Institute of Health & Development.3 Fragile X syndrome is one of the most common forms of inherited intellectual disability12, and according to a 2009 study, FXS has an incidence in males of 1 in 5161.13 The expansion of this study is of particular importance because “approximately 1/3 of children with Fragile X also receive diagnosis of autism, [and] studying the brain development of these individuals very early on in life will provide important clues about what happens during brain development, when, and why.”3



The Infant Brain Imaging Study began as a project entitled “A Longitudinal MRI Study of Infants at Risk for Autism.”14 The study has expanded with supplemental funding from the NIH, Autism Speaks, and the Simons Foundation Autism Research Initiative, since the initial award of $10 million by the National Institutes of Health in 2007.14 The multi-site study is a collaborative effort between the Children’s Hospital of Philadelphia, University of Washington, Washington University in St. Louis, and is led by researchers at the University of North Carolina at Chapel Hill. Participation in this study is ongoing and interested parents are encouraged to contact the IBIS Network15 if they meet the requirements of having a six month old or younger whose sibling has been diagnosed with ASD. Participants will be reimbursed for travel and related expenses.



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