Abstract
Much evidence indicates that patients with autism spectrum disorders (ASD) demonstrate marked social dysfunction. However, the etiology is still unknown. We have studied social dysfunctions in youth with high- functioning ASD compared with typically developing participants using functional MRI (fMRI). Firstly, individuals with ASD during self- face evaluation demonstrated relatively low self- related activity in the posterior cingulate cortex, and atypical neural responses to self- faces in the right insula. Dysfunction in these areas could contribute to the lack of self - conscious behaviors in response to self- reflection in ASD individuals. Secondly, when the subjects executed finger gestures and observed the gesture, the congruency effects in the extrastriate body area was reduced in ASD group. The finding suggests that the ASD have dysfunction in the extrastriate body area as a comparator of self and other’s action. Finally, we conducted hyper- scanning functional MRI while the subjects performed real- time joint- attention task. The findings showed that the impairment of joint attention in ASD is related to hypo- function of early visual processing. Furthermore, in ASD patients, a reduced inter- subject synchronization of the right inferior frontal cortex may be related to the difficulty in understanding shared intention through eye contact. These aberrant neuroimaging findings could be social brain marker in ASD.
