Friday, December 11, 2015

CAR Research: Attention and Gaze Hold Clues to Social Development in Autism

Children with autism spectrum disorders (ASD) focus their attention on social information differently from their neurotypical peers, and this gives us a glimpse into social development as they mature. Improving our understanding of how these differences work may provide clues to developing treatments and interventions to ease some of the social symptoms of autism spectrum disorders (ASD).

CAR psychologist
Benjamin Yerys, PhD, studies attention, impulsivity, and distractibility in ASD, as well as in ADHD and anxiety- ASD’s frequent companions. A pair of his studies contribute to our understanding of how children with ASD prioritize and respond to social information in their environment.


“Now you see it….”: The Attentional Blink Effect in Autism


The first study tested what’s known as the “attentional blink effect” in 8-14 year-old children diagnosed with an autism spectrum disorder (ASD) vs. typically developing peers. Attentional blink refers to a gap in the brain’s ability to detect visual information when it appears in rapid succession. (Think about trying to identify a single card as someone shuffles the deck.) This is a result of a brief “overload” in the brain’s capacity to process information. Essentially, the brain needs a brief moment of unawareness, equivalent to a “blink”, to recover its ability to pay attention to new visual information. This idea is best explained with an example. Imagine you’re shown a series of images of different shapes on a screen, each appearing for a fraction of a second. You’re told to look for a triangle, and that a heart shape may also appear in the series. It’s highly likely that you’ll notice the triangle, but will miss the heart shape while your brain recovers its ability to focus on the images.

The exception to this rule is when the visual information carries emotional weight. For example, if an angry face is among the images shown after the picture of the triangle, you will be more likely to notice it, meaning the “blink” effect is overridden by a strong emotional stimulus. 

When this study was previously conducted in adults with ASD, those on the autism spectrum were less likely than neurotypical adults to pick up emotionally-charged images. However, when Dr. Yerys tried this same test with children using photos of dogs, neutral facial expressions, and angry facial expressions, the children diagnosed with ASD performed just as well as – or slightly better than - their typically developing peers. This was a surprising finding because the amygdala area of the brain is very important for processing emotional information quickly, and this area of the brain develops atypically in ASD starting in toddlerhood. This means that in children with ASD, the ability to prioritize social-emotional information is somehow preserved. Further research is needed to determine if this would also hold true for children more severely affected by ASD.

“Although we were initially surprised, this finding does make developmental sense,” said Dr. Yerys. “In general, adolescents and pre-adolescents tend to have a heightened response to emotional information. It is important that emotionally-charged information may grab attention to the same degree for kids on the spectrum as those considered to be typically developing, because it means that this age range may present a window of opportunity for possible interventions.”


“Inhibition of Re…what?” Visual Search for Social Information Differs for Children on the Autism Spectrum


In a related study published in November, Dr. Yerys and his colleagues explored social attention in 8-17 year-old children by looking at how children shift their attention to search their environment, instead of responding by reflex to the environment as we saw in the attentional blink study. When children (or adults) search their environment, the brain tends to favor searching new locations instead of going to old locations. For example, if you lost your keys then you may be more interested to look for them in your desk rather than searching your pocket a second time. This process is called “
inhibition of return” (IOR).

In neurotypical development, people tend to automatically skew their attention toward social information (facial expressions, body language, emotional cues), as opposed to objects in their environment which carry no social significance (an electrical outlet, a tree, a particular toy).

Earlier studies have established that photos of angry or upset faces hold the attention of neurotypical individuals longer than smiling or neutral faces (because anger and worry indicate a potential threat). The threat-related faces override or delay the brain process that would usually cue the brain to move on and scan for new visual information. Until now, no studies have carefully examined whether this “override” effect would also hold true for people with ASD.

To test whether children with ASD would prioritize socially or emotionally charged information in a similar way, children in this study were given a series of tasks to complete on a laptop. They were instructed to respond as quickly as possible to various combinations of non-social symbols and sets of photos showing either neutral or angry facial expressions.

Dr. Yerys and his team found that young people with ASD were less accurate in their responses; they also had longer response times when compared with their typically developing peers. Children who had the most severe ASD symptoms were also the slowest to shift their attention. This is the first large study to show that this visual attention mechanism (IOR) is disrupted in children with ASD, and that this impaired attention is directly related to some of the core social symptoms of ASD.


The study also ruled out the possibility that this difference in attention is related to ADHD or anxiety symptoms, which are common in children diagnosed with ASD. The study results support the overarching hypothesis that problems with how children prioritize social or emotional information in visual attention is associated with more severe social impairments.

Putting it all together
Taken together, the “attentional blink” study and the “inhibition of return” studies indicate that emotional information captured the attention of adolescent and pre-adolescent children with ASD to the same degree as it did for their typically developing peers, when information was being gathered from a single point in space. However, adding the task of scanning a given area for information and then determining its social meaning may prove more difficult for children with ASD.

It also appears that social-emotional processing proved more difficult for children with more severe symptoms of ASD. The findings of both studies suggest that impairments in early visual attention processes have a cascading effect on social development in ASD. This is further borne out when we consider that similar studies done with adults showed greater impairments for those with ASD; and in studies with infants at high-risk for ASD [by virtue of having an older sibling with a diagnosis], infants with slower attention orienting are more likely be diagnosed with ASD later in childhood, compared with those infant siblings who do not go on to receive a diagnosis.

The two studies offer insight into specific cognitive and brain mechanisms that may contributing to core symptoms of ASD. Our center’s long-term goal is to translate this knowledge into opportunities for improving both diagnosis and intervention, with the goal of diminishing the cascading effect of early impairments to social-emotional development.



Special Thanks...We want to thank the 100+ families that made these two studies possible by participating in research! We’d love to hear your questions and feedback about your participation at
autism@email.chop.edu.

To learn more about participating in research at CAR, visit
www.autismMatch.org or email us to learn about studies for neurotypical and autism spectrum participants from infancy through young adulthood.

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