Brain Mechanisms for Perceiving Emotional Information in Body Movement in Children with Autism

Background: Researchers and clinicians have suggested that individuals
with autism might find faces aversive to look at, particularly the eyes. The tendency to not look at faces, be it driven by aversion or a failure to understand the significance, has been used to explain poor performance on emotion identification tasks using faces (Adolphs et al., 2005; Pelphrey et al., 2002), and lower levels of FFA and AMY activation during emotional face viewing (Dalton et al., 2005; Hadjikhani et al. 2004). Research by Blake et al. (2003) demonstrated that children with autism exhibit deficits in the perception of biological motion. However, we do not know if children with autism process emotional information conveyed through biological movement differently than TD children. Do children with autism have difficulty with emotional processing in general whether it is conveyed through facial features or through body movement? Are these difficulties related to underlying neurological processing differences in autism in emotional brain areas?
Objectives: This fMRI study used a male silhouette (with no observable facial expressions) that moved with a happy, angry, or sad gait. We examined whether the different walks triggered emotion-based brain regions and whether these patterns differ between children with high-functioning autism and age and IQ-matched TD control children.
Methods: Data collection is ongoing. We have analyzed data for eleven children with autism (ages: 7-15 years, mean=11.6; FSIQ: 83-135, mean=108) and five TD children (ages: 9-13 years, mean=10.8; FSIQ: 98-134, mean=115). The children passively viewed the video while lying in a 3T Siemens Allegra scanner.  The stimuli were created to convey three different emotional conditions—happy, sad, and angry---using parameters from previous research about emotional information conveyed by gait.
Results: Overall, preliminary results indicate that viewing the angry walk elicited a greater BOLD response than viewing a happy walk in both the children with autism and the TD children in the right STS. The autism group also had greater activation than TD in right parietal and right STS when viewing the angry walk and in bilateral STS when viewing the sad walk. The TD children had greater activation than the autism children in bilateral middle temporal and left STS when viewing the happy walk. The children with autism had no greater BOLD response when viewing the happy walk than when viewing the non-moving figure during the baseline condition.
Conclusions: As in previous studies with typically developing adults with emotional processing in faces, the amount of activity in the STS was modulated by happy and angry emotional body movement such that anger elicited a greater BOLD response than happiness for both groups of children.  Differential processing is evident in that the children with autism have a greater response than the TD children in right STS for anger, the strongest of the three emotions.  Significant differences between the groups occurred during the processing of the positive emotion of happy with the autism children failing to respond differently than a neutral condition.