I agree with all the suggestions so far and wanted to add one more unmentioned technique. While the you tube vidoe offered information about endorphins with a lowered head, there's another endorphin related technique that quickly results in a lowered head. I understand it's a bit controversial, but ENDOTAPPING has been a wonderful introduction to training my mare. If your not familiar with endosticks, or endotapping: It's just a firm foam ball on the end of a whip/crop/bat as opposed to a lash or loop. My mare had some challenges with nervousness, fleeing, and stiffness. I made an endotapper with a dressage whip, a foam ball (Walmart party supply sale), balloon, and liquid rubber or liquid electrical tape. Within the first 10 min. every time I tapped her - and anywhere I tapped her- she immediately lowered her head and stood still. Some think it's just another desensitizing tool, but it's really helped my groundwork with my mare. I find just a couple minutes before we begin anything, and she's more receptive to working and feeling good.