Early detection of autism is a critical goal in promoting earlier treatment and intervention for children with autism. Research being conducted at the Center for Autism and Related Disorders (CARD) at the Kennedy Krieger Institute in Baltimore, Maryland is focusing on early detection and intervention in
autism. This research has been spearheaded by Rebecca Landa, Ph.D., Director of CARD, and implemented through the CARD research program, Research and Education for Autism in Children (). The goal of this program is to understand causes of and develop treatments for Autism Spectrum Disorders (ASD), particularly to identify early signs of autism and evaluate treatment strategies for toddlers with ASD.
The search for improved methods for early detection has included determining early physical (e.g. head circumference) and behavioral markers, as well as finding biomarkers that could be used to develop medical diagnostic tests. The search for potential biomarkers is progressing, and while this particular area of research is vital, improving early detection requires continued research into all areas of early development including early cognitive and behavioral milestones.
A recent study led by Dr. Landa and partially funded by CAN, found that differences between typically developing children and children with ASD can be discerned as early as age two using a standardized general developmental measure, paired with clinical judgment. The study followed the performance of 87 children on the Mullen Scales of Early Learning (MSEL) at 6, 14 and 24 months. The MSEL examines gross and fine motor abilities, visual reception, and receptive and expressive language, and thus provides measures of a number of areas known to be impaired in individuals with autism. The performance of three groups of children was compared: unaffected children, children with autism spectrum disorders, and children with language delay. To determine this classification the children were administered the Autism Diagnostic Observation Schedule (ADOS) and the Preschool Language Scale (PLS) at 24 months in addition to a clinical evaluation.
The researchers found that at 14 months of age, children with ASD performed worse than unaffected children in four of the five areas. The one exception was visual reception, which is a known relative strength of children with ASD. At 24 months, children with ASD had lower mean scores than the unaffected group in all areas. Moreover, the ASD group performed worse than the language delay group in receptive language, as well as gross and fine motor skills. The researchers also found that the children with ASD showed an overall slower rate of development, with a marked decrease in the period between 14 and 24 months. This study identifies areas in early development that may be indicative of a later diagnosis of autism and could be used as early warning signs, before observable concerns such as delay in speech onset are reported by parents. It also supports growing evidence that autism diagnoses can be made in young infants and toddlers.
Following up on this research, the next line of inquiry is whether such warning signs of autism can now be used to push diagnosis to as early as the first year of life. Therefore, with support from a CAN Young Investigator Grant to post-doctoral fellow Anjana Bhat, Ph.D., Drs. Landa and Bhat are examining autism-specific impairments in visual attention, affect, and learning in children at risk for autism (infant siblings of ASD children) at 3 and 6 months of age. Children with autism are known to have impairments with joint attention (the ability to orient one's attention to where others are directing theirs), shared positive affect (e.g. shared smiling or laughing), and social orienting (e.g. orienting to name). Delays in these very early developmental milestones could be pre-cursors to later impairments. Developing a means to identify these delays could be used as an early indicator of risk for autism.
This on-going study is using a modification of a standard psychological learning paradigm, called the Mobile paradigm, to measure a number of the developing systems in young infants. In the Mobile paradigm, an infant learns that increased kicking of a leg can produce movement in a standard crib mobile. In addition to measuring how well the child learns the pattern, the infant's emotional responses, visual attention, and motor coordination can be measured, all which represent development in systems relevant to autism. Using a modified mobile paradigm, the children's performance will be compared with their performance on the MSEL at 3, 6 and 18 months. At 18 months, assessments will also be administered to determine if there is evidence for a provisional autism diagnosis. The study will be important for determining if there are early identifiable autism deficits for infants in the first 6 months and will test the efficacy of the paradigm as an assessment tool for determining these early warning signs.
“Introducing behavioral interventions even one year earlier can make a tremendous difference in the lives of children with autism and their families,” said Dr. Landa. “If we are able to educate professionals to identify red flags in development we can then recognize and diagnose the disorder at one-and-a-half or two years of age, instead of three or four, allowing for earlier intervention and ultimately better outcomes.”
To read the press release on Dr. Landa and Dr. Garrett-Mayer's study,
To read the complete abstract for Drs. Bhat and Landa's on-going study click here.
Click on the link to read about studies in CAN's .
Landa, R. & Garrett-Mayer, E. Development in infants with autism spectrum disorders: a prospective study. Journal of Child Psychology and Psychiatry. 2006 47(6): 629-638.