Applications of ERPs in Autism Research and as Functional Outcomes of Neuromodulation Treatment

摘要

The review is aimed to explore the abnormality of neural and functional connectivity in autism resulting in executive function deficits by measuring performance on cognitive tests with event-related potential (ERP) recording. Analysis of ERP components is one of the most informative dynamic methods of investigation and monitoring of information processing stages in the human brain. Different amplitude and latency characteristics of ERP components at specified topographies reflect both early sensory perception processes and higher-level processing including attention, cortical inhibition, memory update, performance error monitoring and other cognitive activities. ERPs provide a method of studying cognitive processes in typical subjects, and also provide a sensitive instrument to assess differences in individuals with neurodevelopmental pathologies. Despite significant advances in functional neuroimaging (e.g., fMRI), the ERP measures still represents an important tool for brain research in psychiatry, as many psychiatric diseases correlate with certain altered patterns of ERP responses. Such ERP alterations can either serve as valid biological markers for functional diagnostic purposes or for better understanding of the cognitive functions which are disturbed in neurodevelopmental disorders such as autism spectrum disorder (ASD). Information about stages of signal processing during experimental manipulations can be obtained from ERP. In general, ERPs can be categorized as short-latency (e.g., N100) or long-latency (e.g., P300) ERPs, as they reflect early-stage, modality-specific and late-stage polymodal associative processing respectively. Response-locked ERPs such as error-related negativity (ERN) and positivity (Pe) are also considered as important indices of such executive function as error monitoring. The goal of the review which is based mostly on a series of studies conducted by our research group was to compare behavioral (reaction time, accuracy) and electrocortical biomarkers (frontal and parietal stimulus- and response-locked ERP) of executive functions during performance on a visual three stimuli oddball task with illusory figures and in oddball with novel distracters between children with autism spectrum disorder and typically developing children, to analyze group differences, and explore if low frequency repetitive transcranial magnetic stimulation (rTMS) administered over prefrontal cortex in children with ASD will improve behavioral and ERP measures during post-treatment test in the same oddball tasks. Application of ERPs in ASD treatment research is an approach aimed at validation of specific ERP measures as sensitive functional outcomes of experimental neuromodulation interventions such as rTMS and neurofeedback. The chapter will discuss several other aspects of ERP methodology usefulness in autism research and treatment.