Emergence of Cortical Activity Patterns as Infants Develop Functional Motor Skills.

Abstract

Despite the careful examination of the developmental changes in overt behavior and the underlying muscle activity and joint movement patterns, there is very little empirical evidence on how the brain and its link to behavior evolves during the first year of life. The dynamic systems approach and theory of neuronal group selection provides a framework that hypothesizes the development of the CNS early in life. However, the direct examination of the changes in brain activation that underlie the development of functional motor control in infants have yet to be determined or tested. The goal of my dissertation was to use functional near-infrared spectroscopy (fNIRS) to document the changes in brain activation patterns as infants acquired functional motor skills. My studies show that fNIRS is a viable and useful tool to examine brain activity in the context of infant movements. My findings demonstrate that as the behavioral and motor outcomes improve, the underlying neural activation patterns emerge. When functional motor skills are unstable and not fully functional, larger areas of the broad brain regions are recruited. As the skills become more reliable and functional, the brain activation patterns become refined and show an increase in strength of activity. The results from the studies in my dissertation take an important first step of describing the typical neural patterns that emerge with functional motor skills early in life. This work will help future studies build the body of empirical evidence that will improve our knowledge regarding the developing link between brain development and behavior. Finally, these studies provide foundational knowledge to better understand the atypical development of the CNS in those with disabilities.