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Seminar Announcement Date: Wednesday, 20 August 2025 Time: 3.30 PM Venue: Seminar Hall A unified model of cortico-hippocampal activity through neural field theory Richa Phogat University of Newcastle. 20-08-25 Abstract
Functional interactions between cortex and hippocampus play a central role in cognition and are disrupted in major neurological disorders, yet the mechanisms underlying coordinated cortico-hippocampal dynamics are poorly understood. We address this challenge using neural field theory, a biophysically-grounded framework for modelling large-scale neural dynamics. We first show how the autonomous activity of cortex and hippocampus emerges from cortico-thalamic and hippocampo-septal feedback loops, respectively, giving rise to cortical alpha and hippocampal theta rhythms. Next, we integrate these two systems through topologically and topographically informed coupling between the cortex and hippocampus. Weak coupling yields spatially precise correlations between cortical and hippocampal activity, consistent with neurophysiological recordings. Stronger coupling pushes both the cortex and the hippocampus toward criticality, triggering state transitions and mode mixing, such that activity propagates across spatial scales and reorganizes both cortical and hippocampal dynamics. Such disruptive, unstable processes provide an explanation for the frequent involvement of the hippocampus in seizures. This prediction is validated using intracranial electroencephalographic data from human patients with focal onset epilepsy. Together, these results establish a geometrically and biophysically grounded framework that gives a unifying account of large-scale cortico-hippocampal dynamics and provides a physically principled foundation for studying other distributed brain systems. Speaker bio: Dr. Phogat is a Computational Neuroimaging Fellow at the University of Newcastle, working with Professor Michael Breakspear. Her research focuses on computational modelling and analysis of macro and meso-scale brain activity. You can read more about her work
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