An ERP Study On The Disorder In Contextual Information Processing In Chinese Children With High-Functioning Autism

Autism is a neural-developmental disability.According to the Weak Central Coherence theory,it is difficult for autistic patients to effectively integrate contextual information.However,more and more studies suggest that autistic patients integrate contextual information,and they suspect that the difficulty is closely related to inhibition deficits.It is necessary to use the new experimental design to explore the obstacle mechanism of autistic context processing.The Chinese children with high function autism are strictly selected as subjects,and typical developing children matched with age,IQ and semantic level are selected as the control subjects.With the help of event-related potential technology,the lexical semantic priming paradigm is used to investigate how autistic children use word contextual information to promote recognition and semantic processing by comparing the conditions whether prime word and target word are semantic relevant or irrelevant.At the same time,the display context is added in prime stimuli as interference.The process of using contextual information and inhibiting useless information is investigated simultaneously.Contrasting the activation and inhibition of contextual information to help clarify the mechanism of contextual processing disorders in autism.According to the study,the two groups of children have the same EEG components during processing,indicating that the context processing model of autistic children is similar to that of typical developing children.However,the longer reaction time and the difference of EEG components between groups indicate that it is difficult for autistic children to use contextual information.And more cognitive efforts are also needed.In terms of the cognitive process of context processing,there is no difference between groups in the N1、P200 and N400 of prime stimulus,which indicates that the semantic activation ability of autistic children is intact.It is suggested that the difficulty of using contextual information in autism occurs in the process of integration or inhibition in the later stage of processing.Firstly,autistic children can integrate contextual information.The similar N400 effect to the typical development group shows that autistic children can automatically integrate the contextual information of target words and prime words.At the same time,the LPC component is more positive when the target word is semantically related to the prime word,which shows that autism strategically use contextual information.Secondly,autism is difficult to inhibit the interference of useless information.On one hand,the picture that unrelated to the target word affects the early attention allocation and processing efficiency of autistic children.On the other hand,the semantic information of picture affects the semantic processing of the subjects.The N400 of autistic children is more negative when the background picture and target word are semantic irrelevant,and the LPC is more positive in relevant condition.However,there is no difference in the typical development group between different conditions.It indicates that the typical developing children successfully inhibit the excitement of interfering information.It is difficult for autistic children to inhibit previously activated information and resist to interference of information from a potentially attention-capturing stimulus.To sum up,the study believes that the difficulty of contextual information processing in autistic children is not stems from the inability to activate,but from inhibition deficits.Autistic children automatically activate contextual information and form expectations to promote the processing of target words.At the same time,they strategically use contextual information according to experimental tasks,but autistic children can’t inhibit the interference of task-independent contextual information.It increases the cognitive burden and leads to the difficulty of context processing.