Why is the hippocampus the most common starting point of focal epilepsy that resists drugs? · Grey Matter

The hippocampus is built for strong recurrent excitation and plasticity, which serve memory and also let activity spread and synchronise easily.

Why is the hippocampus the most common starting point of focal epilepsy that resists drugs?

The hippocampus is built for strong recurrent excitation and plasticity, which serve memory and also let activity spread and synchronise easily. Its pyramidal cells, CA1 above all, are among the most vulnerable in the brain to injury such as a prolonged febrile seizure, and their loss leaves a shrunken, scarred hippocampus, called hippocampal sclerosis. In the surviving circuit, the mossy fibres of dentate granule cells sprout back onto granule cells and form recurrent excitatory loops, and some inhibitory interneurons are lost, so the tissue becomes easier to synchronise and harder to calm with drugs.