Chase isn't fond of doorways between rooms, particularly if there's anything even slightly blocking it or if a baby gate is propped near it but not even blocking any of it. I guess I've knocked over baby gates often enough that he's afraid he'll knock it over himself. He scrambles through like something is going to attack him. Not all doorways, only if there's some potential attack item nearby.
My sister's dog was scared to death of the sound or action of her shaking out clothes prior to folding them. Flap a shirt in his direction and he'd zoom out of the room so fast you'd wonder if he'd been there in the first place.