摘要 : Abstract The social and communicative difficulties that characterize autism spectrum disorder (ASD ) are considered the most striking feature of the disorder. Research has reported that individuals withASD show abnormalities in th... 展开 Abstract The social and communicative difficulties that characterize autism spectrum disorder (ASD ) are considered the most striking feature of the disorder. Research has reported that individuals withASD show abnormalities in the brain regions associated with the processing of social information. Importantly, a recent study using functional nearinfrared spectroscopy (fNIRS ) found the first evidence of atypicalities in the neural processing of social information in 4 to 6monthold infants at high familial risk ofASD . These findings provide an important step in the search for early markers ofASD and highlight the potential for neuroimaging techniques to detect atypical patterns of neural activity prior to the manifestation of most behavioural symptoms. This study aimed to extend the findings of reduced neural sensitivity to social stimuli in an independent cohort. Twentynine 5monthold infants (13 lowrisk infants, 16 highrisk infants) were presented with social and nonsocial visual stimuli, similar to the previous experiment. Importantly, a nonsocial dynamic motion control condition was introduced allowing the comparison between social dynamic and nonsocial, static, as well as dynamic stimuli. We found that while lowrisk infants showed activation to social stimuli in the right posterior temporal cortex, this activation was reduced in infants at high risk ofASD . Although the current sample size was relatively small, our results replicate and extend previous work and provide evidence for a social processing difference in infants at risk of autism. Future research will determine whether these differences relate to an eventualASD diagnosis or may rather reflect the broader autism phenotype. 收起