Mirror Neuron Network Dysfunction as an Early Biomarker of Neurodevelopmental Disorder

Overview

Background: People show changes in brain activity when they watch other people do actions. This may be part of early social and communication skills. Researchers want to understand the stages of normal development of motor observation and imitation in people and how it relates to social development in infants and toddlers. Objective: To study the nature of brain activity that underlies typical brain functioning in infants, toddlers, and adults. Eligibility: Infants ages 8 12 months Healthy adults ages 18 65 Design: Adult participants will have one visit. They will: Answer questions about their family, like its size and ethnicity. Answer questions about their own behavior and do a simple motor task. Have EEG/fNIRS. A damp elastic cap with small sensors will be placed on the head. Participants will observe stimuli, either on a video screen or of a live person. The sensors will be connected to a computer. That will record the participant s brain activity while watching pictures on a screen. Infant participants will have 2 visits. Their parents will answer questions about their family. The parents will fill out forms about their child s development. These will be mailed to them before each visit. Parents will stay with their infant while study staff does an assessment of the child s communication, motor, and thinking skills. Infants will have EEG/fNIRS. Infants who are at risk for developmental delays will come back for another visit when they are about 2 years old. This will repeat the infant visits but it will not include EEG/fNIRS. Some questionnaires and assessments will be videotaped.

Objective: This investigation has two main objectives: 1) combine two child-friendly brain imaging techniques and stochastic modeling to determine the neural basis for the development of imitation and mimicry in human infants and 2) use machine learning to identify brain activation patterns that predict impairment in imitation and mimicry in infants at risk for social communication disorders. Study Population: This study will focus on two groups of infants. The first group includes 60 typically developing infants, who will complete the imitation and neuroimaging paradigm between the ages of 9-12 months (+/- 2 weeks) and again at 12 months of age (+/- 2 weeks). The second group includes 60 infants at increased risk for social communication disorders, including those with motor delay, language delay, preterm birth, or a sibling with an autism spectrum disorder. These infants will complete the imitation and neuroimaging paradigm at 12 months of age (+/- 1 month) as well as a follow up evaluation of social communication skills and developmental status at 24 months of age (+/- 1 month). Design: We propose to conduct longitudinal studies of changes in EEG and fNIRS correlates of mirror neuron network activity in typical development and infants at risk for social communication delay. We will measure both EEG mu suppression and hemodynamic change over the motor cortex during an established infant action/observation paradigm. At all study visits, infants will also complete developmental assessments that measure abilities in cognitive, motor, language, and social domains. Outcome measures: Both neuroimaging measures and developmental status will serve as outcomes for this study. For the typically developing infants, change in the neuroimaging metrics (i.e., percent mu suppression, percent oxyhemoglobin change) will be used to characterize development of the mirror neuron system, while the relation between neuroimaging variables, their trajectories, and developmental ability will be used to develop hypotheses about the role of the mirror neuron network in development of social communication skills. For the infants at risk for social communication disorders, the main outcome will be developmental status, with neuroimaging metrics used as predictors.