Wednesday, January 27, 2016

Switching Lenses: A Shift in Perspective Led Researchers to Unexpected Results About Face-Processing in ASD


Humanity seems to be “hard-wired” to pay attention to faces and facial expressions. Zeroing in on faces (rather than other body parts or objects) and being able to differentiate between people’s identities or expressions is one of the first skills developed during infancy; and differences in social attention appear to be one of the earliest observable signs of autism.
Because reduced attention to and interest in social information is a prevalent symptom of ASD, many studies have focused on comparing two groups - those on the spectrum vs. those with typical development - to search for differences in how they prioritize faces compared with other objects in the environment. However, no one had studied individual differences along the continuum of “face expertise”, without taking diagnostic labels into account. A group of CAR scientists led by Julia Parish-Morris, PhD, and Coralie Chevallier, PhD (now at INSERM), believed that ignoring diagnostic categories in favor of a more “dimensional approach” might improve our understanding of how humans develop their facial recognition skills and might also shed light on how differences in attentional biases or motivation to look at faces might influence the development of social skills.
For their study, the researchers enrolled 110 children between the ages of 6 and 17 (50 typically developing and 60 with ASD). The children participated in a series of scientifically validated tests, including Let’s Face It! - a computer game-based intervention designed help teach facial processing skills- to assess their ability to recognize both a person’s identity and perceive differences in facial expressions. They also watched short videos showing faces and objects, while their eye movements were tracked to measure gaze and attention. The team assessed each child’s behavior and social using the Social Communication Questionnaire (SCQ).
“We were surprised to find that, overall, children with ASD and their typically developing peers spent a similar amount of time looking at faces and objects,” explained Dr. Parish-Morris.
Interestingly, children who paid more attention to facial information were better able to differentiate between face identities and facial expressions in the Let’s Face it game, and so did children who performed better on the SCQ.

According to Dr. Parish-Morris, “The connection between attention to faces and face processing skill held regardless of whether or not the participant had autism. This suggests that face processing is truly dimensional and linked to underlying differences in social attention or motivation.” The Social Motivation Theory of autism suggests that while these differences might start small, they could have a snowball effect on face processing skill over developmental time.

Using a dimensional approach to assess social processing in autism is gaining favor across multiple areas of mental health research, and is consistent with a growing trend to think of ASD in terms of neurodiversity. Just as autism displays itself across a wide spectrum of symptoms and characteristics, it can be helpful for researchers to take a spectrum-approach as well, rather than adhering to strict diagnostic categories at the outset.

Shifting the lens through which we study ASD creates the potential for new pathways to understanding the variability that makes the diagnosis so challenging. Parish-Morris and her colleagues are interested in further exploring  the relationship between social interest, social motivation, and a person's  ability to identify and interpret faces as a potential area of interest for developing effective skill-building tools.

No comments:

Post a Comment