 Thus, because the crownpiece of a bridle passes over the poll joint, a rider can indirectly exert pressure on the horse's poll by means of the reins, bit, and bridle.The poll is especially important in riding, as "correct" flexion at the poll joint is a sign that the horse is properly on the bit.Over-flexion, with the poll lowered and the neck bent at a cervical vertebra farther down the neck, is usually a sign that the horse is either evading contact or that the rider is trying to pull the horse onto the bit, rather than correctly ride from behind.