New in JNeurosci, Dorit Kliemann and James Traer, from the University of Iowa, led a research collaboration to compare brain activity between people with autism spectrum disorder (ASD) and individuals who do not have autism.
The researchers analyzed data previously collected at Indiana University and Caltech. These data were measured by recording the brain activity of adults with and without ASD as the participants watched different movies. Movie selections spanned across a variety of genres, including animation, action, romantic comedy, or Hitchcockian thriller. The researchers used the imaging data from these viewing sessions to train a computational model that searched for relationships between brain activity and sounds, visuals, or abstract social features of the scenes. Once trained, the model accurately predicted activity across different brain systems. Kliemann emphasizes the relevance of this approach to studying social difficulties in ASD, adding, "The computational model allowed us to look for robust brain responses to many different aspects of the complex, dynamic contexts in the movies."
When comparing group averages, the model predicted activity in different brain systems similarly for adults with and without ASD. However, comparing individuals to each other within each group revealed that individuals with ASD strayed more from their group average. This higher level of variability in activity was observed in nearly all the brain systems the researchers assessed, but it was most striking in the social brain system.
The researchers stress that because current approaches to understand and treat ASD rely on group average comparisons, this work emphasizes the need for a new perspective. Says Traer, "We were surprised by the similarity of group averages. The results suggest that we need to focus on understanding the details of individual brain responses. How and why do they differ?" Adds Kliemann, "Identifying ASD subgroups may help us build a more precise understanding of the condition and help develop ways to provide individually tailored support." The research team plans to continue exploring how, where, and when this variability in brain activity relates to individual differences in behaviors related to ASD.
