Proprioception and Proprioceptive System

This system begins with information receivers and it ends with action suppliers. Between these two extremities, there is a complex mechanism. There is an afferent pathway to the brain. Proprioceptive information is received by the brain, it is treated at this level and then submitted to a perceptive mechanism.

The disease occurs when the proprioceptive perception is disturbed. Perception depends on the information coming from different receivers and not just from one kind of proprioceptive receiver. Let's consider the perception of verticality. Information comes from the eyes, from the feet, from the inner ears, from antigravitic muscles, from tendons, from fascias and from joint receivers. Suppose these pieces of information are not coherent amongst themselves... the result is unbalance, vertigo or dizziness. As so, these receivers have shown they are intrinsically linked and integrated by a common brain mechanism. That is why they represent a system.

The proprioceptive system includes not only the perception of the body but also the perception of the body in space, the EGOCENTRIC LOCALIZATION. It is impossible to understand the consequences of the proprioceptive dysfunctions without this knowledge.

The proprioceptive system is a slow neurological system, which means it works with at a low speed in afferent and efferent pathways. Proprioceptive centers receive information from the classical proprioceptive body receivers but also from vision and inner ears. Vision has two kinds of neurological pathways: the well known retina-cortical pathway and the retina-colicular pathway but only this secondary pathway belongs to the system.

Low-powered prismatic lenses use this colicular pathwayto reach the brain and manage the proprioceptive system.

The Optician and Active Prisms

Usually, Optician Schools are not able to train opticians in setting active prisms. It requires a very specialised know-how and understanding. This kind of glasses must respect oculomotricity rules to be effective. Opticians are usually trained to set passive prisms. The shape of the frame and the method for centering lenses must follow specific rules. The optician is part of the therapeutical team and he/she must be integrated as a working element. Otherwise, the entire work is at risk. Since we are providing the brain with new information, this information must be highly precise. Multifocal lenses represent a hard task for opticians. Setting the prescribed prisms in the correct place, respecting oculomotrocity rules and choosing the correct frame requires deep knowledge and special training.

Usual optical lenses only have one main task. It consists of putting a focused image on the retina. Active prisms have a different main task. It is to inform the brain. The technical parameters to be respected are different even from passive prisms.

This kind of active prisms needs a frame with a minimum of deepness. For small children, the minimum is 29 mm deep; for other people 30 mm deep; and for multifocals, no less than 32 mm.

The frame must be curved and tilted in order to respect the physiology of eye movements. Both temporal fields must be symmetrical, which means the centering rules must be different from the usual. The orbital asymmetry must be taken into consideration. This means new rules for frame adjustment.

In conclusion, only a specif training for opticians can guarantee good results. Standard opticians do not possess enough knowledge to prepare glasses with active prismes. They can do it, but the results will not be good because they will be missing the correct rules.

Increasing Attention by Furniture Modification

Usual school furniture is aggressive on the proprioceptive system. As so, we decided to modify the usual school furniture by use of sloped desks, limb supports and specially-shaped chairs.

We studied the attention levels of 2 classes composed of 8-year-old children.

In one of them, we used the standard furniture and we equipped the other one with special furniture.

The difference in the results for the two classes lead us to conclude that the non aggressive proprioceptive system furniture can increase attention levels.

In the same study, we also evaluated the number of spelling mistakes and we observed that, before the special furniture, both classes had the same level of spelling mistakes. 4 months after that, the class equipped with special furniture reduced its mistakes 4 times more than the non-equipped class.

We also studied the reading speed and reading ability of both groups. The special-equipped group presented much better results than the non-equipped.

4 months later, we studied both classes and verified that, in the class equipped with our special furniture, there was a reading improvement of 24.4 percent. In the non-equipped class, we verified an increase of only 7 percent, which could easily be due only to the fact that the children were now 4 months older.

We have also been studying the reading speed and the spelling mistakes in another school. The first results are showing a very high performance in the group equipped with special furniture when compared to the non-equipped group. The quantifiable results are still in progress.

Proprioceptive aggression doesn't harm the intellectual level but it can terribly harm the execution level, which is the main factor of learning disabilities.

Correct Standing Position

Some attendees to the San Diego Seminar are asking whether correct standing position is similar for every person or not. Also, they want to know how to assess the short leg situation through a postural point of view.

The situation is as follows:

Both legs are symmetrical concerning the medial plan but opposite concerning the antero-posterior body gravity centre. When we put the right leg behind the shoulders, the gravity centre moves forwards. Also, when we put the left leg behind the shoulders, the gravity centre moves backwards. In case of PDS, the body gravity centre is displaced backwards. In order to correct this anomaly, we must put the right leg slightly behind. This is similar for every person. This is true for usual standing position on a flat surface.

However, when you bend the leg, i.e. to use the stairs, the opposite is true. When people put their right foot on the stairs, the centre of gravity moves forwards. But when people put their left foot on the stairs, the shoulder and the body gravity centre moves backwards.

The majority of short legs are not actual short legs, they are the consequence of asymmetrical muscular tonus. It is a mistake to put a single compensation insole under the short leg because it increases the pression on this limb and enhances the muscle tonus's asymmetry.