Anyone know anything about head wagging in horses when ridden?

[HorseLove!]

I recently did a dressage test with my horse and in the comments they said he was head wagging at times. I'm not fully aware of this however i presume it means his head isn't still on the contact when being ridden? Does anyone know what causes this and have any ideas on how to make the contact more consistent. He was in a drop nose band and since we have gone back to the cavasson he does seem better. Thank You for any answers.

 

[kirstykate]

Keep you hands still, you must be fiddling

 

[Jontydoggle]

It generally happens in trot, when the rider is rising to the trot. It's caused where the riders seat is not entirely independent and as a result a backwards pull is created on the reins during the rise and fall. Try to focus on feeling like you are pushing your hands towards the bit (without actually moving them). Your arms should feel quite solid while you do this. Also, think about your arms staying still and rising 'through' them, so they don't go up and down with your body.