To understand the meaning of a conversation, kids
automatically do what adults do besides processing
the meaning of words, they unconsciously "read" the
expression on a person's face and listen to their tone
of voice, then integrate that information with the
context at hand to discern meaning, be it humor,
anger, irony or straightforwardness.
Individuals with autism typically don't do this.
They often miss the subtle meanings conveyed by a
person's face and tone of voice, and thus have trouble
determining the communicative intent of others.
Neuroimaging studies have backed this up, showing that
individuals with autism spectrum disorders (ASDs)
including autism, pervasive developmental disorder and
Asperger's syndrome show reduced activity in the
regions of the brain that respond to such cues.
But what if those brain regions could be trained to
respond appropriately? In a report in the current
issue of the journal Archives of General Psychiatry
and currently online, UCLA researchers did just that.
Providing ASD children with explicit instructions to
pay more attention to facial expressions and tone of
voice elicited an increased response in the medial
prefrontal cortex, part of the brain's network for
understanding the intentions of others.
"That's significant. The fact that you can
'normalize' activity in this region in the ASD group
by directing their attention to these important social
cues clearly indicates there's nothing intrinsically
wrong with this region in the autistic brain," said
Mirella Dapretto, associate professor of psychiatry
and biobehavioral sciences at the Semel Institute for
Neuroscience and Human Behavior at UCLA and a member
of the UCLA Ahmanson-Lovelace Brain Mapping Center.
Dapretto co-authored the study with her former
graduate student Ting Wang, who is now a postdoctoral
fellow at Mount Sinai School of Medicine.
"This is a very positive thing," Dapretto said,
"because these findings have implications for future
interventions they suggest that you could train the
autistic brain to make use of the information conveyed
by the human face and voice to successfully navigate
social interactions."
Autism is a complex neurobiological disorder of
development that affects one of every 150 children,
impairing communication and social skills. ASDs
encompass a broad spectrum of disorders that range
from mild to severe.
The authors had two goals in mind with their study.
One was to examine the neural circuitry in the brain
that underlies the problems ASD children face in
interpreting communicative intent. The other was to
determine whether explicit instructions to pay
attention to facial expressions and tone of voice
would elicit more normal patterns of brain activity in
these children.
While undergoing functional magnetic resonance
imaging (fMRI), 18 ASD boys between the ages of 7 and
17, as well as a control group of 18 typically
developing (TD) boys, viewed cartoon drawings of
children in conversational settings while listening to
short vignettes that ended with a potentially ironic
remark. Researchers found that, compared with the TD
control group, the ASD children had reduced activity
in two areas of the brain the medial prefrontal
cortex and right superior temporal gyrus. But when the
researchers gave both groups explicit instructions to
pay attention to the speaker's facial expression and
tone of voice, only the ASD children showed a
significant increase in activity in the medial
prefrontal cortex.
"The typically developing kids recognized and
interpreted these cues automatically when trying to
infer if a speaker's remark was sincere or sarcastic,
so their brains were already responding
appropriately," said Dapretto. "But not so with the
ASD kids, who did not show activity in this area when
specific instructions weren't provided. This is the
first study to show that you can normalize activity in
a key region of the so-called 'social brain' in
individuals with autism by simply directing their
attention to these important social cues."
Other authors of the study included Susan S. Lee
and Marian Sigman. The research was funded by the
National Alliance for Autism Research, the Cure Autism
Now Foundation, the UC Davis M.I.N.D. Institute, and
grants from the National Institute of Child Health and
Human Development and the National Institute on
Deafness and Other Communication Disorders.