The neuron is the smallest element
of the nervous system. To compose a system, several neurons should be
associated. We know that only one neuron is in relation to several tens
(hundreds, thousands?) other neurons.
Since the vocation of sensitives
neurons
, is to inform the higher centers, it should be supposed that a
considerable sum of information arrives at the nervous system, in a continual
way. Such a quantity of information, even for our brain, cannot be treated
quickly. Nature employed other means.
The constant objective of the
natural evolution, remains the survival of the species. Survival passes by the
knowledge of the environment and the adaptation to this environment. The
adaptation calls upon strategies. Some of these strategies can apply to our
neurons :
- Information must be transmitted.
- Information must be useful.
- The treatment of events must be fast.
To apply these strategies, certain
means should be activated :
- The redundancy. Significant information should
not be lost.
- Filtering. Only, significant information must be
transmitted.
The simple fact, for example, to
apply, to a member, an object, carry a deformation and thus a stimulation
which exceeds the surface of object contact. The coding of intensity
is proportional to the distance from conctact.
The more intense the support
becomes, the more the quantity of stimulated sensors, increases. We have well a
redundant system which makes it possible to mitigate the failures of the
sensors located under the object. As long as the integrity of the latter, is
respected, it seems that do not perceive a feeling of those which are around the
object. We filtered information. This filtering can take several forms ;
- The form which appears most probable is
discrimination. Because the contact is limited to a surface, the sensors of
contacts located under this surface are excited and inhibit the transmission of
information of the sensors of tension located at the periphery. This inhibition
can take place on the level of the spinal cord. This inhibition has several
advantages;
- It is concentric, more one moves away from the
center, more it is significant.
- It limits the number of information.
- It is fast.
- It does not utilize the higher centers.
- Another possible form is integration. Our
strategies are also the fruit of trainings. These trainings support certain
networks. It has, therefore, advantages;
- It can be modified.
- It utilizes our conscience.
It is possible that the means used
are multiple.
