Pupillometry used to examine the advantage children with ASD have on visual tasks

Written by: Dr. Signe Bray

People with ASD have an advantage in certain types of visual tasks, for example finding a specific item in a crowd of distracters.  This is true in children as young as two, the youngest age when you can reliably make a diagnosis. This study set out to better understand why, by using eye-tracking technology to monitor eye movements in children during a search task. They took advantage of the fact that our pupils dilate more when we undertake effortful cognitive tasks.

The authors compared two groups, ASD and typically developing, each with 17 toddlers aged 21-35 months.  The toddlers played a game where they were shown a red apple that flew into the screen. The apple disappeared and then re-appeared in a display among other similar-looking objects. The toddlers then looked at the display for four seconds. The eye tracking was used to see if the toddlers ‘found’ the apple – did their gaze land on the apple during that four second period?

The study found that pupils contracted more in the toddlers with ASD, when they played this ‘find the apple’ game. This might mean that a specific brain system that controls attention is more readily engaged in ASD, which can explain why people with ASD have an advantage in visual search tasks.

 

Examples of the visual search images participants were shown.  (Figure from Blaser et al., 2014)

Examples of the visual search images participants were shown.  (Figure from Blaser et al., 2014)


Reference:

Blaser E., Eglington, L., Carter, A.S., Kaldy, Z. (2014). Pupillometry reveals a mechanism for the Autism Spectrum Disorder (ASD) advantage in visual tasks. Scientific Reports. 4.