Written by: Ivy Cho
One of the key building blocks in building and maintaining social relationships is the ability to process and understand the meaning behind facial expressions. Unfortunately, in individuals with Autism Spectrum Disorder (ASD), where impaired social functioning is a hallmark, the ways by which emotional faces are processed is still unclear. Some research studies suggest emotional processing deficits, while other studies have reported no such deficits. Specifically, research regarding emotional face processing in ASD adolescents is sparse, and this is disappointing as adolescence is a transitional period with change and higher levels of stress – all factors that can have an impact on the processing of facial expressions. With this in mind, there is great importance in investigating emotional face processing in adolescents with ASD.
A research group at the University of Toronto, has recently investigated emotional processing in adolescents with ASD using a neuroimaging technique called magnetoencephalography (MEG). MEG, looks at brain activity by measuring electrical currents coming from the brain.
This study measured different areas of the brain while participants underwent a task looking at angry, happy, and neutral faces. Twenty-four adolescents with ASD and twenty-four typically developing adolescents, all between the ages of 12-15, underwent this task during MEG. During this task, participants were shown two images placed on either the left or right side of the screen. One image was that of a facial expression and the other was a scrambled pattern. Participants were told to press a button that corresponded to the side with the scrambled pattern. This task measured both the accuracy and the time until a response was recorded.
The study found 2 interesting results after examining brain activity in response to this task. Firstly, they found that adolescents with ASD showed lower accuracy in the task when the emotion presented was an angry face. Secondly, adolescents with ASD showed different brain activity patterns when processing happy and angry faces to that of typically developing adolescents.
These results suggest implications regarding social behavioural difficulties that adolescents with ASD face. Inaccurate perception of facial expressions (like angry faces) and differences in facial affect processing in the brain may be contributing to the social impairments found in ASD.
This study expands the current sparse literature regarding facial processing in adolescents with ASD and the specific deficits seen. Hopefully, this will help in further understanding how facial processing in ASD ties in with social behavioural deficits.
Leung RC, Pang EW, Cassel D, Brian J, Smith ML, Taylor MJ (2014) Early neural activation during facial affect processing in adolescents with Autism Spectrum Disorder. Neuroimage Clin 7:203-212.