What Causes Recurring Seizures?

My son is 35 years and was brought to the hospital over the weekend. He was weak and clammy, had shakes ,pasted out and went into some kind of seizure. The hospital ran all kind of tests, everything came back negative, and they released him. He was brought back to the hospital for the same simtoms, but this time he not responsive. Again everything came back negative. He is not talking normal, not making sence. They released him again, because everything came back negative. The advised us to follow up with a Neurologist. He is still not talking right , says his brain is in a fog. he keeps picking up things and holding on to them, not wanting to give them back. keeps saying we got to give up something. witch doctor should we see first. A neurologist or a phyricists. I hope you understand this, I can t spell and I m typing fast, because he keeps roaming out side.