Modeling of entorhinal cortex epileptic activity 1 Submitted to the Journal of Neurophysiology Revised version Realistic modeling of Entorhinal Cortex field potentials and interpretation of epileptic activity in the guinea-pig isolated brain preparation
نویسنده
چکیده
246 words) Mechanisms underlying epileptic activities recorded from entorhinal cortex (EC) were studied through a computational model based on review of cytoarchitectonic and neurobiological data about this structure. The purpose of this study is to describe and use this model to interpret epileptiform discharge patterns recorded in an experimental model of ictogenesis (guinea-pig isolated brain perfused with bicuculline). A macroscopic modeling approach representing synaptic interactions between cells subpopulations in the EC was chosen for its adequacy to mimic field potentials reflecting overall dynamics rising from interconnected cells populations. Therefore, intrinsic properties of neurons were not included in the modeling design. Model parameters were adjusted from an identification procedure based on quantitative comparison between real and simulated signals. For both EC deep and superficial layers, results show that the model generates very realistic signals regarding temporal dynamics, spectral features and cross-correlation values. These simulations allowed us to infer information about the evolution of synaptic transmission between principal cell and interneuronal populations and about connectivity between deep and superficial layers during the transition from background to ictal activity. In the model, this transition was obtained for increased excitation in deep versus superficial layers. Transitions between epileptiform activities (interictal spikes, fast onset activity (25Hz), ictal bursting activity) were explained by changes of parameters mainly related to GABAergic interactions. Notably, the model predicted an important role of GABAa,fast and GABAb receptor-mediated inhibition in the generation of ictal fast onset and burst activities, respectively. These findings are discussed with respect to experimental data.
منابع مشابه
Pig Isolated Brain Preparation and Interpretation of Epileptic Activity in the Guinea Realistic Modeling of Entorhinal Cortex Field Potentials
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Realistic modeling of entorhinal cortex field potentials and interpretation of epileptic activity in the guinea pig isolated brain preparation.
Mechanisms underlying epileptic activities recorded from entorhinal cortex (EC) were studied through a computational model based on review of cytoarchitectonic and neurobiological data about this structure. The purpose of this study is to describe and use this model to interpret epileptiform discharge patterns recorded in an experimental model of ictogenesis (guinea pig isolated brain perfused ...
متن کاملEntorhinal Cortex field potentials and interpretation of epileptic activity in the guinea - pig isolated brain preparation
246 words) Mechanisms underlying epileptic activities recorded from entorhinal cortex (EC) were studied through a computational model based on review of cytoarchitectonic and neurobiological data about this structure. The purpose of this study is to describe and use this model to interpret epileptiform discharge patterns recorded in an experimental model of ictogenesis (guinea-pig isolated brai...
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Slow (<1 Hz) periodic activity is a distinctive discharge pattern observed in different cortical and sub-cortical structures during sleep and anesthesia. By performing field and cellular recordings, we demonstrated that slow periodic events (0.02-0.4 Hz) are spontaneously generated in the entorhinal cortex of the in vitro isolated whole brain of the guinea pig. These events were characterized b...
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