MYONET - Atlas Musculature Orofacial System

Atlas Musculature: Specialities II,B,1,2,3

 Erhard Thiele     020e Atlas Musculature Inventory       MYONET.TOTAL PROGR CONTENTS  

1.2.2 Discussion of the Physiology and Muscular Specialities of the Muscles of Area II

–        Tongue Musculature –

The musculature of the tongue can be viewed in two groups from insertion and origin.

The extrinsic muscles connect the body of the tongue with the neighbouring bon and, thus, give it its movability in the Cavum oris.

The intrinsic muscles have both fixing points within the muscular mass helping the tongue to its manifold moulding. With its systematical structure of the intrinsic muscle fibres with their tendineous ends the tongue body shows a sort of connective tissue internal skeleton. From its form and function it is compared with a "shear-grid"(J. W. Rohen, [136]). As shown in picture 24 it consists of two planes set in a right angle. The horizontal plane makes the Aponeurosis situated below the tongue surface. On its median line directed downwards in a right angle stands the sheet of the tongue septum.

Talking about the intrinsic musculature: As picture 23 shows the muscle fibres are arranged in presumably three lateral-symmetric blocks. The big central block is formed by the vertical and transversal fibres; the two rather laterally situated, a high and a deep one, mainly consist of longitudinal fibres. This gives the muscle fibres within the tongue body a strict layout in the three space planes standing rectangular to each other.

II/B1, the longitudinal fibres tend to shorten the tongue (see also the chart "Synergisms" below comparing action and effect.).

II/B2, the Transversal fibres, forming the tongue body slender and long, are interwoven to a room net within the main block of the tongue body --

II/ B3, --together with the vertical fibres, flattening the tongue.

The picture 23 showing the intrinsic musculature is schematically dividing separate blocks what is rather interwoven in a three-dimensional grid ("shear-grid") in the organism, which lends it a three-dimensional formability.

Basic tongue functions through intrinsic muscle synergism

Synergisms

 

contract:

Musculi -

 

Transversales & Verticales

Transversales & Longitudinales

Verticales  & Longitudinales

 

extend:

Musculi -

 

Longitudinales

Verticales

Transversae

effect =

Tongue body form:

 

tongue long and slender

tongue short and high

tongue short, flat, broad

The muscle actions can happen 'in toto' or in parts of the tongue, combined in any stages of synergisms and antagonisms, symmetrically or asymmetrically, uni- or bilaterally. This results in an extremely manifold moulding of the tongue. Its huge movability within the oral cavity is assigned to the tongue through the trampoline like action of the oral Diaphragma and especially trough the three muscle tracks of the extrinsic musculature of the tongue depicted in image 22 which, being fixed on bone, run into the tongue body allowing them to pull the tongue to an fro like a ship fastened at the pier. They start on the bone and run into the tracks of the three-dimensional grid of the intrinsic muscles.

II/A, 1.   M. styloglossus

arises from the bony Processus styloideus of the maxilla (styloid process of the temporal bone) and leads into the longitudinal tracks of the intrinsic musculature from up back at the tongue base continuing till the tongue tip. Parts are previously branching off into the transversal tracks; this allows flexing and directing of the tongue to the sides. The general pull goes back and up enabling primarily the last third of the tongue to move palatal for deglutition and the forming of specific sounds as [g] and [k].

II/A, 1a.  M. palatoglossus

stems from an Aponeurosis of the Palatum molle (soft palate) with  contralateral contact nearly forming a muscle ring through its insertion into the tongue border and its leading in into the intrinsic transversal tracks; contracts the rostral palatine arch.
II/A, 2.  M. genioglossus
has its fixing point at the inside of the chin tip (Spina mentalis) and runs fanning up in an arch form into the whole length of the tongue body, in the front more vertically, at the back more longitudinally. This makes him act antagonistic to the Styloglossus (A1) predominantly to frontal but down as well. This downward component shows specifically with the following muscles:

 

II/A, 3. M. hyoglossus

originates at the hyoid bone and inserts into the transversal and longitudinal tracks. It keeps the tongue down-backwards. Through their interaction with the intrinsic muscle tracks the extrinsic ones cause a shaping as well, besides the dislocation of the tongue body. During these actions two of the pulling directions are working in antagonism to the third so that it gets stretches when the other two are contracting. This is described in the above survey (see shear grid). Changes of form and site mostly happen fluctuant from one instant to the next like during the combination of sounds (S-canal) or they run through the tongue body in a wave movement during the retral movement of the superficial "dimple" during deglutition (Peristalsis). B. Wein demonstrated this during his lecture ”Gestörte Zungenbewegungen im sonographischen Bild”  at the 9th Congress for Myofunctional Therapy for the model of drinking to move portions of liquid to the fauces [176)

II/A, 3. M. chondroglossus
has its origin at the Cornu minor of the Hyoid and, ascending, passes through the Longitudinales and the Genioglossus until its fibres beam into the Submucosa of the tongue. This results in a downward pull of the tongue.

On this item B. Wein published two papers:

”Computer-sonographische Darstellung der Zungenmotilität mittels Pseudo-3 D-Rekonstruktion”. Die Autoren schreiben: ”Zungenbewegungen sind Ausdruck einer komplexen Zusammenarbeit verschiedener intra- und extraglossaler Muskelgruppen unterschiedlicher Hauptverlaufsrichtungen und einer differenzierten Innervation. Sie werden üblicherweise durch direkte Inspektion beobachtet. Die Bewegungsbeobachtung bezieht sich dann auf die maximale Auslenkung der Zunge sowie auf grobe Veränderungen des Bewegungsmusters. Insbesondere der Schluckakt entzieht sich jedoch der Inspektion, da er nur bei geschlossenem Mund als reflexartiges Geschehen ablaufen kann” [177, S. 95]. Ähnlich äussern sie sich in ”Ultraschalluntersuchungen von Koordinationsstörungen der Zungenbewegung beim Schlucken” [179]. 

In the translation:

"The Computer Sonographic View of the tongue motility through a Pseudo-3-D-Reconstruction ".The authors write: Tongue movements are the manifestation of a complex cooperation of the different intro and extraglossal muscle groups of different main routing directions and a differentiated innervation. They are commonly monitored through direct inspection. The movement observation is in that case directed on the maximum deflection of the tongue and further on rough changes in the movement pattern. Especially the deglutition act evades an inspection as it will only take place reflectively when the mouth is shut  [177, S. 95]. They report similar observations in the paper: Ultrasound Examinations of Coordination Disorders during Deglutition.[179]. 

 

In the same fluent way happens the broadening and narrowing movement during the mastication process to direct the foodstuff between the mastication planes of the teeth. In resting position the tongue will show a slightly convex surface (exercise: CAT’S HUNCHED BACK) the tip tapping against the incisal papilla (exercise: POINTPOSTURE  ) and the border of the tongue (rim) touching slightly the molar teeth. (There is a suggestion not to use the term "tip of the tongue" but rather call it the rim as it gives a abetter description of the front in its rest position.). Moreover has this tongue resting posture a much higher importance besides the inside/outside balance as meditative prescriptions and similar health rules are de- and pre-scribing this posture quite precisely. So the resting and functioning tonicity of the tongue will have to be adjusted to the extern facial musculature in equilibrium (ball-shell-picture). To a great part the intrinsic but as well, in synergism, the extrinsic tongue musculature and additionally the correspondingly the tongue position influencing mouth floor muscles represent the centrifugal power in the inside of the "ball" which is complemented by the "shell" of the outer orofacial muscles with their centripetally directed power. Our hard tissue "capsule" between the elastic inner ball and the outer shell - i.e. the jawbones with the dental arches - which can so easily be deformed is surely not distorted by the "normal" functions even if those do not take place eufunctionally and in a muscular equilibrium. Functions are exerting by their fluent pressure changes a very short-time influence. The pressure influence from histological view has to be so permanent that it effects an activation of bone building and demolishing cells (blastic and clastic cells) which finally brings about the transformation.

In this precisely tuned synergistic and antagonistic function course of the tongues intrinsic and extrinsic and mouth floor musculature against the outer "belt"muscles we witness a classical example for the principle of a bio-feedback regulated functional sensorimotor loop as they are governing the physiology in the whole organism. These feed-back circuits are able to grant a physiological equilibrium for the establishment of eu-function and continuation of the form of the supportive textures in a neuromotor way, respectively, in case of an unbalanced neuromotor tonicity to blow up the frame and collapse function and structure.