Epilepsy is a state of altered cortical excitability resulting from an imbalance between excitatory and inhibitory neural circuits. The common understanding is that the complex neuropathologic changes in an epileptic brain establish a diffuse hyperexcitable epileptogenic system.[1] Animal studies have shown that various factors like selective loss of neurons, alteration in membrane kinetics, deafferentation and sprouting of collaterals results in hyperexcitability and neuronal synchrony that are sufficient to cause seizures.[2,3] The hyperexcitability is maximum at the epileptogenic focus which may spread to the adjoining as well as distant areas of the brain through pre-existing neuronal networks as well as neocortical neuronal sprouting.[4,5] Studies on cortical excitability done in humans also hypothesize a similar concept of diffuse hyperexcitability in epileptic individuals.
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