Issue link: https://www.massageandbodyworkdigital.com/i/812910
technique MYOFASCIAL TECHNIQUES Uncoupling the Neck and Jaw By Til Luchau If you place your hand on the back of your neck and open your jaw wide, what do you feel? Does your neck extend slightly? Do your neck muscles contract a bit when your jaw drops (Image 1)? If so, you're likely feeling what Moshé Feldenkrais called "parasitic contraction" — habitual muscle activity and tension not necessary for the movement being performed. 1 Of course, I wouldn't suggest using the term "parasitic" when talking to your clients about their movement (it's a creepy word, and as therapists, it's good to remember that our language has the power to shape our clients' body sense, in both helpful and unhelpful ways). The point is, in normal circumstances you don't need to tighten or extend your neck in order to open the jaw. Using these extra muscles actually takes more effort, and just adds tension to an area that usually has plenty of that already. There are many examples of these unnecessary and inefficiently paired movements in the body—the shoulder might lift when the arm reaches; the eyebrows arch when singing loudly; the jaw clenches when opening a jar. There may be a reason for these pairings, in certain situations—extending your neck when opening the jaw can help you open a bit wider, for example; but to the extent that these patterns become unconscious, automatic, and habitual, they can cost us in lost movement efficiency and ease. Paired movements of the jaw and cervicals are very common—in one small but often-cited study, all participants' necks extended with jaw opening (and to a lesser extent, flexed with jaw closing). 2 That study's authors speculated that this coupling was related to the jaw and neck's shared innervation via the trigeminocervical nucleus in the upper cervical spine. But we should be clear that shared innervation doesn't have to mean "automatically and always linked"; we differentiate the movements of structures with shared innervation whenever we refine our movement skill. For example, the thumb, and the first, and second fingers are all innervated by the median nerve, but can easily learn to operate independently in complex and refined ways, such as in typing, playing a musical instrument, or performing a manual therapy technique. Likewise, we can also learn to move our jaw independently of our neck; the posterior cervical muscles do not need to contract in order to open the jaw. Try it yourself: return your hand to the back of your neck, and practice letting your jaw gently fall open while your neck stays relaxed and long. Allow your tongue to soften (because interestingly, cervical motion can be inhibited by tongue position 3 ). Make sure your shoulders are relaxed, and your breathing is easy. Most people find it is much easier to open the jaw when these other structures are relaxed. 1 Does the back of your neck contract or extend when you open your jaw? C h e c k o u t A B M P 's l a t e s t n e w s a n d b l o g p o s t s . Av a i l a b l e a t w w w. a b m p . c o m . 97