Let's rule out pain right now, I'm almost certain that is not the case.
I ride a friend of mine's older Arab mare and when I get on her or have her in the round pen she tosses and flips her head...a lot! Any truth to the rumor that Arabs just like to toss their heads more? How do I get rid of this behavior because honestly the owner doesn't always mind (but she only ever does trail) but I can't stand it! I'm supposed to get this mare out and exercise her but I can't be productive with an unruly head toss every 10 seconds.
Would work with a cercingle/side reins work? What should I try undersaddle?