Some dogs get what is known as partial /Aura seizures. Unlike a seizure that renders the dog unresponsive, shaking, and stiff, partial seizures show a change in behavior. Some dog will pace, circle, act frightened, become clingy to the owner, snap at imaginary flies, wander, hide and there are many more behaviors that can be seen with this. Some dogs are predisposed to epilepsy and others just get what are known as idiopathic seizures, meaning there is no known cause. I am going to direct you to sites that talk about this along with a site of breed directory. Find your breed then click on it to open the page. If you scroll to the bottom you will see prone illnesses of that breed.