17351
Rest Cerebral Blood Flow in the STS Correlates with Social Perception Impairments in Children with ASD
A lack of preference for relevant social features is one of the main clinical characteristics of ASD. During the last decade, the use of eye-tracking methodology has allowed an objective and quantitative characterization of this social perception deficit in children with ASD. In addition, several brain imaging studies have suggested that abnormalities within the superior temporal sulcus (STS) could be related to social impairments in autism.
Objectives:
In this study, we aimed to objectify social perception process in children with ASD using eye-tracking in order to investigate a putative correlation between social perception impairments and rest functional brain activity. For this purpose, MRI arterial spin labelling (ASL) was used to measure rest cerebral blood flow (rCBF).
Methods:
Thirty-two children with ASD diagnosis based on ADI-R (mean age = 7.7 ± 3.4) participated on this study and underwent an eye-tracking study followed by an MRI-ASL study. Tobii T120 eye-tracker was used to measure participant’s number of fixations to the faces of the characters during passive visualization of social scenes. MRI-ASL was used to measure rCBF. Whole brain regression analyses were performed on the smoothed and normalized ASL images using number of fixations to the faces as covariate within SPM8 (http://www.fil.ion.ucl.ac.uk/spm).
Results:
ASL-MRI whole brain analyses showed a significant positive correlation between the number of fixations to the face and rest CBF in the right posterior STS (p < 0.001 uncorr). Children who looked less to the face of characters during visualization of social scenes where those who had the lower rest CBF values in the right pSTS.
Conclusions:
This results showed for the first time a correlation between a social behavior and a functional brain activity at rest, even though the measurements were unrelated and performed separately. This correlation suggests that social behavior in children with ASD is associated with, and might be predicted by, the level of functional activity at rest within the STS.