Associations between neurophysiological discrimination and clinically observable sensory reactivity features in infants - PROJECT SUMMARY/ABSTRACT Hyper- and hypo-reactivity in response to sensory stimuli, particularly to auditory stimuli, are prevalent across the lifespan in populations with neurodevelopmental conditions including autism. Although hyper- and hypo-reactivity are widely documented in infants at increased likelihood for neurodevelopmental conditions (LNC), the neurophysiological underpinnings of these clinically observable sensory reactivity features have not yet been established in infancy, a developmental period in which the brain is most plastic. Studies have shown differences in neurophysiological discrimination may distinguish autistic and non-autistic school-age children. This suggests that neurophysiological discrimination is a potential underlying mechanism of clinically observable sensory reactivity features. Research with autistic school-age children has shown links between reduced neurophysiological discrimination and hyper-reactivity features, while the research regarding associations with hypo-reactivity features is sparse and conflicting. However, the associations between brain and behaviors have not yet been tested in infants with different levels of risk for later neurodevelopmental conditions. In this proposal I seek to extend research to an earlier developmental period by examining infants with low vs. high LNC levels through two specific aims. Aim 1: Compare within-session trajectories of neurophysiological discrimination responses to auditory stimuli between low and high LNC infants; and Aim 2: Examine how these neurophysiological discrimination trajectories associate with clinically observable sensory reactivity features. Over two years, I will measure neurophysiological responses of discrimination to an auditory in 60 infants aged 9-12 months using event-related potential (ERP). I will also collect behavioral assessments (observed and parent-report) on clinically observable sensory reactivity features. The long-term objective of this study is to elucidate the origins of sensory processing difficulties and their impact on developmental outcomes. The significance of this research lies in its potential to promote a more comprehensive conceptual model linking neurophysiological mechanisms to sensory behavior that can guide more precise clinical assessment and improved intervention approaches in the future. The PI on this training fellowship is a postdoctoral research associate in the University of Southern California’s Chan Division of Occupational Science and Occupational Therapy. The PI will work with a mentorship team of experts in the fields of neurophysiology and clinically observable sensory reactivity to complete a comprehensive investigation of neurophysiological underpinnings of clinically observable sensory reactivity features in infants at varying LNC, contributing to the brain-behavior understanding early in life. This study will help the PI to launch her career as an independent scientist with a research focus on biomarkers of clinical sensory behaviors in infants and young children with varying levels of LNC.
