Neuropediatrics 2006; 37 - PS4_4_3
DOI: 10.1055/s-2006-945806

fMRI FOR THE STUDY OF RESPONSE INHIBITION, AND FACE AND LINGUISTIC PROCESSING IN AUTISM

E Anagnostou 1, L Soorya 1, J Fan 1, K Stamper 1, E Hollander 1
  • 1Mount Sinai School of Medicine, New York, NY, United States

Objectives: The goal of this study is to explore abnormalities in activation of the frontostriatal circuit involved in response inhibition and abnormalities in activation of fusiform/amygdala areas involved in face processing.

Methods: We recruited adult subjects age 18–45 with high functioning autism or Asperger syndrome. And compared them to a group of healthy volunteers matched for age and IQ. The paradigm is designed to test control inhibition, and face processing. Therefore, it includes a go-nogo test, and a face emotion discrimination test. The subjects are shown a series of faces with happy or sad expressions in random order and asked to press the button when they identify one emotion but not the other. The BOLD imaging is performed using a gradient echoplanar (GE-EPI) sequence on a Siemens 3T Allegra system.

Results: For the response inhibition task, subjects with ASD demonstrate decrease activation in the caudate nucleus and anterior cingulate cortex (ACC), indicating a relative deficiency in inhibiting an already initiated action. In addition, there was decreased activation in the fusiform gyrus in response to faces, consistent with previously reported data, and a decrease in locus ceruleus activation, suggesting decreased arousal compared to healthy controls. Lastly, increased activation of ventral striatum and amygdala during the face processing task (face switch and happy and sad face conditions) was observed in affected subjects, which is consistent with response to aversive stimuli.

Conclusions: Preliminary data supports the hypothesis of dysfunction of the frontostriatal circuitry related to the presence of repetitive behaviors in autism. Our data also replicates previous findings of decreased activation of the fusiform face area in response to faces, but also suggests that face stimuli may be perceived as aversive by subjects with autism.