At least one sign of autism
may begin as early as 2 months of life, new research suggests.
The study of 110 babies
found that infants later diagnosed with autism showed a decline in the amount
of attention they paid to other people's eyes beginning at 2 months and
continuing until 24 months.
"We found that signs
of autism are measurable and observable within the first months of life,"
said study author Warren Jones, director of research at the Marcus Autism Centre
at Children's Healthcare of Atlanta.
"These are the
earliest signs of autism ever observed," Jones said, noting they may be
associated with symptom severity.
Children with autism have
impaired communication and social skills and often exhibit repetitive behaviours.
Symptoms may be mild, as in Asperger syndrome, or severe, as in full-blown
autism. It's estimated that one in 88 US children has an autism spectrum
Signs of social disability
Despite the observed
decline in eye attention, the researchers said infants later diagnosed with
autism did pay more attention to people's eyes than was expected.
"This insight, the
preservation of some early eye-looking, is important because, in the future, if
we were able to use similar technologies to identify early signs of social
disability, we could then consider interventions to build on that early
eye-looking and help reduce some of the associated disabilities that often
accompany autism," said Jones.
Autism therapies work best
when begun while the brain is still developing. "This early developmental
window may be an opportunity to intervene that we didn't know we had
before," Jones added.
The findings, released in the journal Nature, need to be confirmed in larger
studies before they can lead to changes in clinical practice.
Deficits in eye contact are
a key sign of autism spectrum disorders, according to background information in
the study. But it wasn't clear when such deficits begin.
Currently, autism is often
diagnosed using a scientifically validated checklist designed for youngsters
between 16 months and 30 months old, according to Autism Speaks.
For the study, the
researchers enrolled 59 babies considered to be at high risk of developing an
autism spectrum disorder because they had a sibling with autism. Another 51
babies were enrolled who were considered low-risk.
To see if they could
pinpoint when lack of interest in other people's eyes begins, the research team
used eye-tracking technology to measure the babies' focus when shown videos of
caregivers engaged in normal behaviours.
The babies were shown the
videos at 10 time points between 2 months and 2 years of age.
By age 3, just one child
from the low-risk group was later diagnosed with an autism spectrum disorder,
compared to 12 youngsters in the high-risk group. Because just two of these
children were female, the researchers limited their analysis to the 11 male
children diagnosed with autism. They compared them to 25 typically developing
children from the low-risk group.
The researchers noted that
the decline in interest in other people's eyes began at 2 months and continued
declining until 2 years.
A significant advance
"This was a very
well-done, very revealing study documenting in a precise and systematic way
that children who are later diagnosed with autism spectrum disorders have
demonstrable and progressive differences in visual regard in infancy. It's a
breakthrough finding," said Dr Andrew Adesman, chief of developmental and
behavioural paediatrics at Steven & Alexandra Cohen Children's Medical Centre
of New York in New Hyde Park, NY.
"Whether this might
permit accurate and reliable diagnosis earlier is still very unclear. But if it
does lead to earlier identification, it may lead to the development of earlier
interventions," he said.
Jones pointed out that
these deficits aren't something that parents would be able to see on their own.
"This is not something a parent can see by just holding a baby. We
collected many measurements over time," he explained.
"Parents shouldn't be
concerned if their babies aren't looking at them 100% of the time, but if they
do have persistent concerns, they should talk to their child's paediatrician,"
The US Centres for Disease
Control and Prevention offers advice on what to do if you're concerned
about your child's development.