Recently I watched movie "Brain on Fire" sorry a big spoiler ahead, in it main protagonist a girl had auto-immune disease so one half of brain got inflamed. Sh

Recently I watched movie "Brain on Fire" sorry a big spoiler ahead, in it main protagonist a girl had auto-immune disease so one half of brain got inflamed. She was showing symptoms like she had schizophrenia. After fixing auto immune problems and brain inflammation everything return to normal with some after effects. That being said and knowing that root canals can get inflamed and that inflammation can spread trough nerves to brain how lightly is the cause of his amnesia has a similar cause? Neurologist among you what is the brain region that is most probably first to be affected if that would happen?