Is it possible for a horse to have arena anxiety? I've noticed when I ride Gun outside the arena, he's much more relaxed, looking around, and listens very well to stopping. When we go into the arena, he becomes tense, moves out a lot more, is extremely sensitive to leg, and doesn't want to stop moving. In the arena, he tucks into the classic dressage headset immediately, without me asking (not that I know how to ask). Outside, he raises his head.
This is an arena I've only ridden him in very lightly, with no pressure to perform, no one watching us. I don't lunge or train him in the arena, and there is no equipment sitting out. I've done it some bareback and some with saddle, and he reacts the same way.
He does have a history of ulcers and had been pinfired in the past, leading me to believe he was competed rather hard. Could he have some form of performance anxiety? How do I help him with it?