| In 1943,Leo Kanner described a group of eleven children found in his Baltimore clinic who exhibited little interest in people and severely impaired social skills.Besides,those children were proved to have IQs under 70 and be recognized as mentally retarded.They are know as Autism Spectrum Disorder.Ever since then,Autism Spectrum Disorder had been regarded as an important mental disorder.With the continuous development of human social cultures and economic levels,more and more people start to seek mental health support and treatment.However,most of those people are blind and helpless when facing various kinds of mental disorders,especially when it is Autism which outbursts in early life and probably lasts for a life-long time.Some of the causes of Autism have been suggested,but the explanation of its causation mechanism is incomplete.Moreover,Autism is a kind of mental disease with a lot of difficulties in early diagnosis,variety of intervention effect and increasing prevalence in the last few decades.Therefore,as a common concern for the whole world,Autism has drew the attention of governments,researchers,educators,and millions of families.Functional Near-Infrared Spectroscopy(fNIRS),a non-invasive neuroimaging tool,has been regarded to have the potential for investigating the neurodevelopment of the young and clinical population.It is a portable,low-cost,insensitive to head movement tool which can be applied in open environment.Integrated with the principles of complex brain network,fNIRS was applied to evaluate the brain function in very young(two-year-old)children with Autism in the current study,aiming to explore their brain activation while watching a cartoon.The time series of oxy-hemoglobin(oxy-Hb),deoxy-hemoglobin(deoxy-Hb)and total-hemoglobin(total-Hb)were acquired to construct the complex networks.The global(i.e.,global and local network efficiency,small wordlness,modularity,hierarchy,and assortativity)and local network features(i.e.,intra-and inter-lobe connectivity)were used to describe the early brain network development of children with Autism.The main focus of the current research is as follows:i.Early features of function network in children with Autism Spectrum Disorder.Twelve young children with Autism Spectrum Disorder and twelve age-and gender-matched healthy controls were recruited to participate in the study.fNIRS was applied to acquire the time series of oxy-,deoxy-,and total-Hb,which were further used to construct the oxy-,deoxy-,total-Hb-based functional network.The global and local network features mentioned before were used to describe the early brain network difference between children with and without Autism.Results indicated that:(1)Weak network efficiency was observed in young children with Autism,even for a wide range of threshold for the binarization;(2)A maximum classification accuracy rate of 83.3%was obtained for all participants by using the k-means clustering method with network efficiencies as the feature parameters,where ?=0.4;(3)Weak lobe-level inter-region connections were uncovered in the right prefrontal cortex,which might be the main cause of weak network efficiency in young children with Autism;and(4)When?=0.4,network efficiency and small worldness might have the sensitivity in representing the early psychopathology of Autism,in contrast,modularity,hierarchy and assortativity would exhibit less sensitivity in doing so.ii.Individual difference of brain functional networks in young children with Autism Spectrum Disorder:relationship with age and severity levels.Fourty-six young children with Autism Spectrum Disorder were recruited to participate in the research.fNIRS was applied to acquire the time series of oxy-,deoxy-,and total-Hb,which were further used to construct the oxy-,deoxy-,total-Hb-based functional network.From the perspective of brain-behavior,the global and local network features mentioned before were used to describe the individual difference(i.e.,age and severity levels)of early brain network features of young children with autism.Results indicated that:(1)Decreased global and local network efficiency of the deoxy-and total-Hb-based functional network were observed in young children with Autism as their age increases;(2)Child's age was proved to be related to global network parameters,such as small worldness,modularity,assortativity,and local network parameters,such as the intra-lobe connectivity in the right Prefrontal cortex and its inter-lobe connectivity with other lobes,in the deoxy-and total-Hb-based functional network.In contrast,it was not related to those parameters in the oxy-Hb-based network.Age was also not related to hierarchy in oxy-,deoxy-,and total-Hb-based network;(3)The severity levels of young children with Autism were prove to be related to the global and local network efficiency in the oxy-Hb-based network;and(4)The severity levels of young children with Autism were prove to be related to other global features,such as characteristic path length and hierarchy,and some of the local features,such as inter-lobe connectivity in the oxy-Hb-based network.iii.The effect of early emotion comprehension intervention on the functional brain network in young children with Autism Spectrum Disorder:a case study.Three children(4-,5-,and 6-year-old)with autism were recruited to participate in the emotion comprehension intervention.Another three age-and gender-matched children were recruited as the control group.Using behavioral evaluation(i.e.,parental report evaluation and formative evaluation),interview,observation,and brain function evaluation methods,we analyzed their improvement of emotion comprehension,autism behavior,empathy,formative evaluation and global/local network features after the 3-month intervention program.Results indicated that after the 3-month intervention program:(1)Children in the intervention group exhibited improvement of emotion comprehension and empathy.Meanwhile,those children showed less autism behavior than before,especially the behavioral problems in Sensory and Relating;(2)The formative evaluation results indicated that children in the intervention group were proved to gain much improvement in cooperation,verbal communication,eye contact,and behavioral problems during the early intervention stage.However,such improvement would reach their plateaus soon and fluctuated only a bit after that;and(3)Brain function evaluation results suggested that functional network features were effective in evaluating the intervention effect on children with Autism.After the intervention,children exhibited improvement in the oxy-Hb-based network efficiency.Besides,other global parameters,such as small worldness,modularity,and hierarchy were proved to grain some improvement as well.Some of the local features(i.e.,intra-lobe connectivity in the left Temporal lobe,and the inter-lobe connectivity in left Prefrontal cortex-left Temporal cotrex,left Temporal cotrex-right Temporal cotrex,left Temporal cortex-right Prefrontal cortex,right occipital cortex-right Prefrontal cortex)were proved to increase after the intervention.In Summary,this is an interdisciplinary study requiring the integration of concepts and methods in Neuroscience,Information Science,Psychiatry,Developmental Psychology,and Education.The innovation in the problem solving methods,its evaluation perspective of the intervention program,and the research questions makes it a novel and helpful research example in this area.It suggests a valuable methodological exploration in the future early diagnosis of Autism Spectrum Disorder by proposing sensitive functional network parameters,which helps researchers gain more understanding of the causes and psychopathology of Autism.Meanwhile,the exploration of the individual difference of age proposes a support for uncovering the sensitive developmental periods of Autism.The variety of functional network features relating to the severity levels in young children with Autism provides new objective evaluation method for the intervention effect,which would be helpful for the setting up of medical and social welfare systems. |
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