Sudden uncontrollable behavior running around in circles starting at one side of the room to the other until I can get a hold of him to hold him and calm him down.He always has dilated pupils and salvia hanging off is his after an episode . Is he having a seizure? He was bitten in the head when he was younger .You would never know that and he is partially blind since then . But he plays and he sleeps with me at night .When he is cold he crawls into the sleeping bag or under a blanket. He is an indoor cat so are the other cats .But I have to dogs that go out just to potty . I am not sure how long ago this circle running started but it is very distrubing when it happens. I am always afraid he is going to die from the strain it causes. Please help?