I have some personal experience with intrusive thoughts. There were times in my life where I have been overcome with thoughts that were not my own. It’s terrifying, especially when the advisors at my disposal just believed that I was completely losing touch with reality. But wait…in the Christian worldview, spirits exist. And Paul even says that we should ‘test the spirits.’ So not only do they exist, but we should communicate with them, and figure out whether they come from God or not. In short, the spirit world can communicate with us.
Neurologists can stimulate different areas of the brain and trigger thoughts. My only thought here is that if a doctor can do this with a probe why couldn’t spirits? If the brain is so altered, surely God [or spirits] could plant thoughts. (A Thousand Brains, p. 37)
And honestly, I think this is how the spirit world works, in part. A spirit would be an entity with a probe of sorts. The inception of thoughts would be plausible.
I say this to say that the statement that ‘thoughts are simply electric activity of the brain’ may very well be true, but the source of that electric activity is the question. If a doctor can simulate thoughts during surgery, surely an all-knowing creator could simulate thoughts as well.
I’d also like to reference the boy that Jesus cured of epilepsy in the New Testament. We are told that the cause of the epilepsy is a spirit. But does that jive with what we know about seizures?
We can induce seizures with electric brain stimulation. If seizures are simply electric charge on the brain, and the spirit world can manifest itself by way of electricity, I think it would follow that spirits could cause epilepsy. I am not saying that all epilepsy is caused by spirits. Or that all spirits cause epilepsy. What I do know is that both of these things are true, and this is how I reconcile them.
TLDR: Thoughts are electrical activity. Seizures are electrical activity. Spirits can plant thoughts, therefore, spirits can cause seizures. And if we can remove spirits in these cases, we can remove the seizures.