The airway dictates much of head posture and hierarchically takes precedence. Check SCMs and Scalenes before and after placing 1, 2 or 3 tongue blades between the molars.

you will also see the head 'correct' its position when the lower jaw shifts (use the "S" sound to locate ideal position.)

also common is 'whiplash type injury that never seems to fully heal (prolotherapy can help there). when head goes forwards, airway improves, but at the expense of Scalenes, SCMs and others finally the Trapezius.

This is the genesis of Tension Type Headaches and many can be reversed with 2 bits of wood!

there is a significant body of EMG and similar work now to link Temporalis and other muscles to such activity. this is seen dentally in questionable approach to orthodontic crowding by removal of teeth. sure it solves the dental issue, but adds to oropharyngeal constriction. Look at the lateral tongue border, 70% of those with Scalloped Borders will have Obstructive Sleep Apnoea and 34% of the female cohort will develop PCOS.

there are many such links that are more recently being established.
DZ

Competing interests: None declared