"Help us understand the cognitive processes and neural systems underlying ASD-DM so that targeted interventions can be developed"
24- 42 months
Children, Autism Spectrum disorder (ASD)
Atypical, rapid early brain enlargement is a distinct neurological characteristic that is observed in 15% of males with autism spectrum disorder (ASD). This trait has been labeled “autism with disproportionate megalencephaly” (ASD-DM) because head and brain growth is disproportionate to height. Evidence from the UC Davis MIND Institute Autism Phenome Project suggests that a higher proportion of children with ASD-DM are minimally verbal at 3 years of age. By 5 years of age, children with this phenotype have made fewer gains in IQ than their counterparts with ASD and normal brain size. At school age, a higher proportion of ASD-DM have IQs in the range of intellectual disability. The short-term goal of this project is to further study the prognosis of ASD-DM children compared to other children with and without ASD. The long-term objective is to fully understand the cognitive processes and neural systems underlying these deficits so that targeted interventions can be developed to improve the prognosis of children with this phenotype.
This study requires
History and Physical Blood draws MRI Behavioral assessments Questionnaires Visual, memory, attention, vocabulary assessments Electroencephalogram (EEG), (test that detects electrical activity in the brain using small, flat metal discs (electrodes) attached to scalp
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Who can participate?
Inclusion criteria for all children: Age at enrollment between 24 and 42 months, no contraindications for MRI, weight at least 20 pounds, living with at least one biological parent, family speaks and understands English, ambulatory, no suspected motor, vision or hearing problems and no chronic health conditions.
Exclusion criteria for all children: Fragile health condition that would prevent the child from participating in the study, presence of any metal or electromagnetic implants that would prevent MRI testing, refusal to allow videotaping of subject during behavioral testing and refusal to allow subject data and biological samples to be shared with other researchers
Specific inclusion criteria for ASD: These are based on the NIH Collaborative Programs of Excellence in Autism (CPEA) standards for children in this age group and include meeting the ADOS cut-off score for ASD and the ADI-R cutoff on either the Social or Communication subscale and within two points of this criterion on the other subscale.
Specific inclusion criteria for TD: Developmental scores within 1.5 standard deviations of the mean on the Mullen Scales of Early Learning (MSEL), Social Communication Questionnaire (SCQ) score less than 11, no diagnosed learning, developmental, or behavioral disorder and no 1st, 2nd, or 3rd degree family members with ASD. Specific recruitment criteria for macrocephaly (for both ASD and TD groups): Head circumference and height measurements from 18 or 24 month well-baby visits will be utilized as inclusion criteria for macrocephaly. Children with head circumference > 95th percentile height < 80th percentile for height OR children with head circumference < 95th percentile and greater than one quartile discrepancy with height percentile will be eligible for recruitment.
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Benefits and risks of participating
We cannot promise any benefits to you or others from your taking part in this research. A brief summary of information about your child’s psychological functioning will be available to you and may be helpful in developing educational and behavioral interventions. The information gained from the MRI scan may be beneficial for future treatment and diagnosis of autism. You will receive a copy of the MRI scan for your medical records. The radiological report and other medical reports may be shared with your family physician (with your consent which will be obtained with a separate consent form). The information gained from the study may be beneficial for future treatments and diagnosis of neurodevelopmental disorders. The benefits of research using specimens include learning more about what causes diseases, how to prevent them, how to treat them, and how to cure them.
Risks and side effects related to the study include:
This is a low risk study with minimally invasive procedures. However, there are possible minor discomforts associated with the following procedures. At times your child may find the behavioral assessment to be boring or difficult. Every effort will be made to lessen any discomfort experienced during the tests.
There may be some discomfort, minor bruising or swelling associated with taking the blood sample. Sterile procedures will be followed but there is a very small chance of infection at the site where blood is taken.
There are also minimal risks to the MRI scanning procedures. You will be screened prior to participating in this study for any potential contraindications that might prohibit your child from participating in the MRI scanning. Your child may experience some anxiety when introduced and becoming familiar with the scanner.
If you tell your family doctor that you are participating in this study, or if you tell your family doctor about any specific aspects relating to your participation, this information may then become part of your medical record with this doctor. Insurance companies routinely have access to such records. We will not release information about you or your family to your doctor or anyone else unless you authorize us to do so.
The study will compensate $50 for each of the completed visits that make up the study. Your child will choose a child-appropriate gift from a grab-bag at the end of each visit. Parking and mileage reimbursement will be provided. Compensation is based on visit and not on the ability to complete tasks during that visit. You will still receive compensation even if you only participate in Part 1 of the study. You may be asked for your social security number for payment purposes. It will not be used for any other purpose without your permission
UC Davis IRB: 1097084
Study duration and period
You and your child will be in this study for approximately one to two months during the first year visits, and then you will return for follow-up visits two years later in which there will be additional tests of your child.
After your behavioral assessment sessions are completed, the research team will send you a summary of how your child did on the tests.