We basically divide Epilepsy into a couple of specific categories. One category is what we call Idiopathic Epilepsy. Idiopathic Epilepsy means, we don't know why they have it. They may have a genetic reason why they have it, but the child is otherwise normal, their brain is structurally normal, and nothing has happened to their brain to damage their brain. That's called Idiopathic Epilepsy. The other type is called Remote Symptomatic Epilepsy. That's pretty much, everything else. That's the child who is born with a brain malformation. That's the child who has had a severe brain injury, in the past, not just now, that's damaged their brain, that has a birth injury or a chemical imbalance. So everything else where the Epilepsy is symptomatic of something else wrong with their brain. There's a huge range of what that can be. The idiopathic ones are somewhat more interesting in a lot of ways. For example, one common type of Idiopathic Epilepsy, is the Mixed Generalized Epilepsy that causes petit mal and convulsions. Almost always, those kids are completely normal, there's nothing else wrong with them. If we scan them, their brain is normal. Another common type is what we call Idiopathic or Age Related Childhood Epilepsy, is a focal onset Epilepsy called Benign Rolandic Epilepsy. These kids are typically otherwise fine. They have seizures that at sleep onset or as they wake up that's almost always focal, so they will start with their face twitching or their hand twitching. Sometimes the seizure will spread. More often, they won't. They are called Benign Rolandic Epilepsy, not because the seizures are all that nice to deal with, but because there is no brain lesion causing it. It's not a symptom of something else. So the division is Idiopathic versus Symptomatic Epilepsy.