Development of Face-Processing Abilities in Infants: Structural and Functional Brain Changes - Project Summary/Abstract This Pathway to Independence Award (K99/R00) will facilitate my transition to an independent scientist who conducts innovative research on the development of face processing abilities in infancy. The apparently effortless ability to recognize faces belies the complexity of this task. The activities described in this proposal are aimed at addressing the structure-function coupling underlying the distributed network of face-sensitive areas by characterizing the white matter (WM) fiber tracts connecting functionally activated regions during the processing of faces. Such an approach has been previously implemented with adults investigating the pattern of fMRI activation in response to faces. Source analysis of high‐density scalp electroencephalography (EEG) recordings is an optimal means to examine brain activity in infancy. Therefore, I propose to investigate the structure-function relationship between source cortical activity of the early low‐level stage of holistic face perception and structural encoding of faces in adults and 12-month-old infants. To better understand the WM connectivity profile within this network, I will define macro- and micro-structural properties (i.e., total volume of fiber bundles, fractional anisotropy – FA, axial and radial diffusivity, and fiber density) of the WM tracts using diffusion tensor imaging (DTI) tractography. Further, I will extend this investigation to younger infants to track the developmental changes in face-processing during the first year of life. As a secondary aim, I will explore structural-functional relations in infants at high familial risk for autism. I propose training and research during the mentored phase (K99) to extend my knowledge and skills in: (1) source localization of EEG activity using advanced source analysis methods and accurate head models; (2) DTI data acquisition and fiber tract reconstruction; and (3) learning tools for conducting research with high-risk infants. The knowledge and skills gained in the mentored phase, as well as the results of the mentored research, will be instrumental to achieving the aims of the independent phase (R00). These specific aims are: (1) track the development of structural brain changes and functional responses to faces in the first year of life to better understand typical and atypical trajectories of the face network; and (2) extend the investigation to other important aspects of face-processing, such as the discrimination of facial identities. I will track structural and functional changes in the processing of faces in infants at 6, 9, and 12 months. This approach will allow us to shed light on the sensitive periods in face perception occurring during the second half of the first year of life. Further, the multimodal approach to define structural-functional development will be implemented to investigate the dynamics of the adaptation effect to individual face perception in infants. My mentorship team is uniquely poised to assist and promote my training and research goals, and to ensure a successful transition to my independent research program.
