Simulation of Abnormal/Normal Brain States Using the KIV Model.

摘要

Recent studies have focused on the phenomena of abnormal electrical brain activity which may transition into a debilitating seizure state through the entrainment of large populations of neurons. Starting from the initial epileptogenisis of a small population of abnormally firing neurons, to the mobilization of mesoscopic neuron populations behaving in a synchronous manner, a model has been formulated that captures the initial epileptogenisis to the semi-periodic entrainment of distant neuron populations. The normal non-linear dynamic signal captured through EEG, moves into a semi-periodic state, which can be quantified as the seizure state. Capturing the asynchronous/synchronous behavior of the normal/pathological brain state will be discussed. This model will also demonstrate how electrical stimulation applied to the limbic system restores the seizure state of the brain back to its original normal condition.;Human brain states are modeled using a biologically inspired neural network, the KIV model. The KIV model exhibits the noisy, chaotic attributes found in the limbic system of brains of higher forms of organisms, and in its normal basal state, represents the homogeneous activity of millions of neuron activations. The KIV can exhibit the 'unbalanced state' of neural activity, whereas when a small cluster of abnormal firing neurons starts to exhibit periodic neural firings that eventually entrain all the neurons within the limbic system, the network has moved into the 'seizure' state. These attributes have been found in human EEG recordings and have been duplicated in this model of the brain.;The discussion in this dissertation covers the attributes found in human EEG data and models these attributes. Additionally, this model proposes a methodology to restore the modeled 'seizure' state, and by doing so, proposes a manner for external electrical titration to restore the abnormal seizure state back to a normal chaotic EEG signal state. Quantification measurements of normal, abnormal, and restoration to normal brain states will be exhibited using the following approaches: · Analysis of human EEG data · Quantification measurements of brain states. · Development of models of the different brain states, i.e. fit parameters of the model on individual personal data/history. · Implementation of quantitative measurements on "restored" simulated seizure state.