Theses

The human brain is a complex and dynamical system that changes throughout the lifetime. Non-invasive imaging techniques, including magnetic resonance imaging (MRI), allow for the measurement of large-scale functional and structural connectivity networks in the brain. Beyond trends, the dynamics across long timescales are still poorly understood. Our research aims to address the question of these long-term dynamics by carefully adapting and applying the stochastic actor-oriented model to brain networks derived from MRI data, specifically in an aging population. The resulting models of network change suggest that the brain is promoting modularity, local efficiency, and short-range connectivity with more adaptive functional networks compared to structural networks. Differences between individuals with and without cognitive impairment suggest a disruption in the maintenance of key brain topology in the progression of cognitive impairment with age. These results are modulated by subnetwork and sex differences that contribute further to the emerging picture of long-term dynamics in aging.

The disciplinarity of science and the future of interdisciplinarity in science is deeply connected with understanding the scope of scientific practice as well as the demarcation and organization of scientific disciplines. These topics, explored through the structure of their subjects, theories, methods, and interpretation, lead to the conclusion that science and its disciplines are largely defined by the integration of philosophical principles into the ethos of the practices rather than by any specific criteria. The ways in which different disciplines behave and interpret philosophies impact how those disciplines are organized and categorized, resulting in deep philosophical and perspective divides between disciplines. As a result of these conclusions, it can be asserted that interdisciplinary research faces many challenges. To combat the discipline divides, careful consideration of the philosophical discipline differences and the limited perspective of individual disciplines is required. Additionally, interdisciplinary research might consider viewing the disciplines as philosophically and socially unique, as well as equally valid and scientific, in order to effectively collaborate on interdisciplinary science and continue interdisciplinary science through time.