Doctoral Dissertation Research: Brain reorganization in human evolution: Connecting structural and functional changes in the inferior parietal lobe

George Washington University, Washington DC

Investigators

Abstract

During human evolution there have been large- and small-scale changes in underlying anatomical structures of the brain. Studying this reorganization is important for understanding the link between structure and function in the brain, and how this relationship may affect cognition and behavior. This project will look at changes in the interconnectedness and anatomy of a region of the brain related to planning and carrying out complex tool making, in humans and a number of non-human primate species. The findings will advance our scientific knowledge about how distinctive human behaviors originated and developed, ultimately contributing to our overall understanding of the origins of modern human behavior and culture. In addition, the project will support a female graduate student in the STEM sciences, provide science outreach to the public, and potentially inform future research on degenerative neurological diseases. The parietal region of the brain, particularly the inferior parietal lobe (IPL), experienced reorganization in the human lineage based on studies of fossil endocasts and neuroimaging scans. The IPL is particularly active in observing, planning and executing tool-use and skilled tool-making. The proposed project will integrate histological analyses of IPL microanatomy and a neuroimaging-based study of function and connectivity between the IPL and other brain regions to investigate reorganization. These methods will be applied consistently across a sample of primate species and humans to address reorganization of the IPL in human evolution. Such an integrative approach will reveal the anatomy of the human and non-human primate IPL and will show how the IPL operates within large-scale functional networks. This study will provide a detailed investigation of human-specific changes in brain evolution within a comparative and evolutionary framework, and can aid in answering questions about the origins of distinctive human behaviors, such as complex tool-making and symbolic behaviors. Thus, studying patterns of brain reorganization in the hominin lineage ultimately contributes to our overall understanding of the origins of human behavior and culture.