Saint-Louis: Evaluating the strength of connections in the brain is one avenue researchers have been exploring to help identify children at risk for autism spectrum disorder earlier in life. Now, researchers at Washington University School of Medicine in St. Louis, with colleagues from the multicenter Infant Brain Imaging Study (IBIS) network, have found associations between brain connectivity and a key social behavior that is a central feature of autism. If it becomes possible to identify children with autism spectrum disorder earlier in life, such knowledge could jump-start efforts to begin therapies that might help improve a child’s language and social skills.
The findings are published online in the journal Cerebral Cortex.
The new study from the IBIS network involved scientists at Washington
University, the University of North Carolina, The Children’s Hospital
of Philadelphia and the University of Washington.
The researchers used functional MRI scans to identify brain networks
involved in a phenomenon called initiation of joint attention. It occurs
when a baby sees an object in his or her environment, such as a dog, a
car or a ball, focuses on that object and — by pointing and/or shifting
gaze — gets someone else to focus on that object. This behavior has been
linked to language development and is impaired in children with autism
“By the time most children are diagnosed with autism, they are 4 ½,
but in studying the brains of younger children, we have found neural
activity that may allow for earlier diagnosis, and that, in turn, may
allow us to begin treatment sooner,” said John R. Pruett Jr., MD, PhD,
co-senior author and an associate professor of child psychiatry at
Washington University. “We’re excited to link aspects of joint attention
behavior to the functional architecture of the brain. This study
represents the first time that has been done in children at an age when
joint attention abilities are actually developing.”
The researchers evaluated 116 young children at 12 months of age and
98 children who were 24 months old. Some children in the study had an
elevated risk of autism because they had older siblings who had been
diagnosed with the disorder. About 20 percent of babies with an affected
sibling go on to develop autism spectrum disorder.
The toddlers’ brains were scanned while they slept. The next day, the
children were assessed to see how often they initiated joint attention —
that is, drew another person’s attention to an object.
The babies less likely to initiate joint attention had strong
connections between their brains’ visual and dorsal attention networks.
The dorsal attention network helps keep attention focused on something
while still allowing the brain to respond to other potentially important
The researchers also identified stronger functional connectivity
between the visual and the default mode networks in babies who were more
likely to initiate joint attention. The default mode network is most
active during quiet rest or daydreaming but generally shuts down while
one is focused on a challenging task.
“When an infant is engaged in initiating joint attention, the visual
and default mode regions tend to work together while the visual and
attention regions tend to decouple, so in these scans we’re seeing
something like a fingerprint of how brain networks coordinate activity,”
said first author Adam T. Eggebrecht, PhD, an instructor in radiology
at Washington University’s Mallinckrodt Institute of Radiology.
“Pointing to direct another person’s attention involves identifying an
object, focusing one’s own attention on it, pointing toward it using the
brain’s motor system and, possibly, perceiving that another person
orients to that object, too.
“Identifying the brain regions responsible for all of that will leave
us better equipped to potentially uncover mechanisms underlying
behavioral features of autism as they emerge over the second year of
Now that those associations have been identified, the researchers
plan to conduct further studies to try to understand how connections
between brain networks might influence children’s language abilities, as
well as their social skills, both of which are impaired in children
with autism spectrum disorder.
“This research lays the groundwork for understanding how
fundamentally aberrant processes develop in the brain as autism is first
emerging in infants,” said Joseph Piven, MD, co-senior author on the
paper and a professor of psychiatry, pediatrics and psychology at the
University of North Carolina and principal investigator of the IBIS