Functional Organization of Large-Scale Cortical Networks After Pediatric Epilepsy Surgery: A Naturalistic fMRI Approach
Year: 2026
Type: dissertation
Study design: Observational Study
Abstract: Unilateral cortical resection in childhood presents a unique opportunity to examine how a single hemisphere supports cognition when deprived of its typical bilateral architecture. Although postoperative outcomes in pediatric epilepsy are often remarkably favorable, the neural organization that enables such resilience remains poorly understood. This dissertation characterizes the multiscale functional organization of the preserved hemisphere using complementary static and time-varying analyses of functional connectivity (FC) during naturalistic movie viewing. Aim 1 examined static FC at multiple levels of organization—whole hemisphere, within- and between-network edges, and individual edges—using Schaefer- and Glasser-based parcellations. Patients showed widespread but spatially heterogeneous deviations from typical large-scale network organization, including altered global patterning of connection strengths and consistently weakened within-network connectivity in both left- and right-hemisphere–preserved groups. Between-network differences were more patient-specific and varied across atlases. Case-series analyses revealed substantial individual variability, with some patients showing minimal deviation and others exhibiting broad, distributed changes. Aim 2 assessed dynamic properties of FC using edge-centric co-fluctuation analysis, high-amplitude (HA) event detection, and template-based characterization of large-scale network states. Global measures of moment-to-moment dynamics were broadly similar between patients and controls. In contrast, event-based metrics revealed selective alterations: patients with a left-hemisphere–preserved brain showed reduced HA-event frequency despite preserved event amplitude, whereas right-hemisphere–preserved patients did not differ from controls. Template-expression profiles indicated individualized deviations rather than a shared patient-wide dynamic signature. Together, these findings demonstrate that post-resection functional organization is distributed and highly variable, with alterations that emerge at different levels of analysis. By integrating static and dynamic measures during naturalistic processing, this dissertation motivates individualized, network-level approaches to understanding plasticity after unilateral pediatric cortical resection.
Source: KiltHub Repository
DOI: 10.1184/r1/33170189
Author: Sophia Robert
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7214036673