The purpose of this research is to understand brain functioning in children with autism spectrum disorders (ASD) and in infants at risk for ASD, and to characterize differences in brain functioning between children with ASD and typically developing children. This is done using electroencephalography (EEG) and eye tracking, both of which are noninvasive ways to look at how individuals respond to events in their environment. EEG allows us to look at brain processing in real-time. Children are shown different events (such as pictures or sounds) while EEG is recorded. The EEG data are then processed and Event Related Potentials (ERPs) are extracted. ERPs represent changes in the brain’s electrical activity in response to an event. They do not require a behavioral response (such as a button press) and therefore are very useful for studying babies and young children, as well as children who may be nonverbal, as are many children with ASD. By using EEG and ERPs we hope to begin to understand how children with ASD may process information, and to then correlate this information with genetic and behavioral data. It is hoped that by clearly identifying differences in brain function at an early age in children with ASD, we will ultimately be able to design treatments that are tailored to the specific impairments of each child.
This research focuses on characterizing several levels of brain processing, from low-level perception to higher-level cognition, in children with ASD. Children and adolescents ages 6 months to 18 years will be shown a variety of paradigms that target specific areas of processing including: (1) low level visual and auditory processing, (2) face processing and joint attention, (3) language processing, (4) implicit memory, and (5) explicit memory. There is no minimum requirement of IQ or verbal abilities, as our methods allow us to study all levels of functioning.
The primary aim of the study is to characterize perceptual and cognitive processing in children with ASD, and high-risk infants, compared to typically developing control children, by using the noninvasive methods of EEG and eye tracking. The specific areas of investigation and paradigms, from low-level to higher-level processing include:
- low-level visual processing
- face processing and associated joint attention
- implicit learning of language and language processing
- implicit memory
- explicit memory
Based on existing literature on EEGs in children with ASD, we hypothesize that we will be able to characterize subgroups of children within the autism spectrum with specific perceptual and cognitive impairments that may help further understand endophenotypes, particularly as informed by their genetic profiles. We particularly are optimistic that we will be able to use EEG to understand neural processing in children who are preverbal or nonverbal, as our current methods of imaging (fMRI) in the Center for Autism Research and Treatment are limited to children who are verbal and higher-functioning. These EEG data will add a rich set of data that will be used in conjunction with the behavioral, genetic and imaging information to better characterize and inform our search for endophenotypes within ASD.