Folks, I have to respectfully disagree here. I'm not sure about OPs situation, but for example my horse's head in constant motion mostly because she's getting excited/alert/unsure about pretty much everything, not because she's uncomfortable with bit or hands. Tiny little move in bushes (and unfortunately we have bushes, ponies, horses, wild life, etc. all around th ring) --> she's as alert as she can be with head up. No noise, head goes down, 30 secs again pony showed up - same reaction. She's not nearly new to all that, she's been taken on trails all the time, but it doesn't go away. Even when she's concentrated on work, she's still very alert. I talked to number of trainers (good trainers BTW), and all of them say she's just that kind of horse. I took her to the open range ring, no horses, no bushes, no wild life, no disturbance, and she worked very nicely, unfortunately it's almost impossible to create such environment every time I school her.