IIn this still fame from the video, Dr. Hauser points to the back of the patient's skull, the occiput bone as it smashes into the patient's C1 vertebrae every time they move their head forward and their chin juts out, as in reaching out for something, looking upwards, etc. When this happens the patient's C1 nerve root and vertebral artery are compressed. This compression would lead to headaches, facial pain, and vibrating sensations in the upper lip.