Date of Award
2025
Document Type
Thesis
Degree Name
Master of Science (MS)
Department
Pharmacology
First Advisor
Jeremy Barry
Second Advisor
David Jangraw
Abstract
Hippocampal oscillations play a critical role in learning and memory. However, it is unclear how the oscillatory generation correlates with corticohippocampal synaptic-dendritic development (e.g., CA1, MEC3-SLM, DG LEC2-OML/MEC2 MML). We used high-density laminar silicon probes (H3, Cambridge Neurotech) to compare hippocampal CA1 and dentate gyrus (DG) theta and gamma spectral properties and PAC in juvenile (P21) and adult (P90) rats. ELS induction was achieved through the recurrent flurothyl seizure induction model (seizures induced at P9-13, 5 seizures/day). We demonstrate significant spectral power, CSD, and PAC changes between ELS induction and P21, and seizure impacts enduring into adulthood. Control adults differ in spectral properties relative to control juveniles, exhibiting greater theta and gamma amplitudes. Relative to control juveniles, ELS juveniles showed significant post-seizure CSD changes with reduced activity in the outer third of the DG somatodendritic axis at OML. In ELS adults, post-seizure maturation precipitates broad DG CSD activity depression and significant PAC shifts at OML and MML synaptic inputs relative to slow theta (4 Hz) and slow gamma (40 Hz). In contrast, control maturation is characterized by increased CSD activity in the stratum radiatum and SLM, theta and gamma spectral property changes, and PAC at corticohippocampal inputs in SLM, OML, and MML relative to all other groups. We propose ELS impairs corticohippocampal circuit throughput development.
Our results are consistent with prior work, suggesting theta and gamma signal properties are network efficacy proxies at specific dendritic compartments that may be necessary for decoding DG corticohippocampal inputs. Our results also suggest post-seizure dysmaturation, distinguishing between short-term and long term seizure impacts as development functions. This suggests ELS result in early hippocampal signaling abnormalities and sheds new light on seizure consequences in the developing brain.
Language
en
Number of Pages
59 p.
Recommended Citation
Weinstein, Caleb Reid, "Early Life Seizure Impact On Corticohippocampal Maturation" (2025). Graduate College Dissertations and Theses. 2096.
https://scholarworks.uvm.edu/graddis/2096