ABSTRACT
A tremor is first observed at the extremities of the limbs during periods of activity. It is analyzed during the ‘serment’ test with an accelerometer placed on the middle finger of the dominant hand. In man it begins between 15 and 20 bars. It increases with the depth and progressively affects all the limbs and the trunk. Fasciculation and myoclonus first appear at the extremities of the limbs. They then reach the limbs and finally the muscles of the neck, face and body trunk. There are also changes of the cortical evoked potentials brought about by different sensory modalities. The cortical excitability cycles are also modified and indicated a cortical hyperexcitability. The effects of pressure itself have been described during hydrostatic compression of aquatic animals. The works of P. Regnard, U. Ebbecke, M. Cattell , for example, have shown that the principal effect of pressure is a stimulation of the central nervous system from 50 bars.
