Experimental study of the structure of the psychodynamic communicability revealed a corresponding complex of symptoms. The complex, as a stable unity, is basically determined by EEG-indices of the lability of the nervous system and, to a lesser extent, - of the strength of the nervous system. There is a linear relation of an integral nature between the complex and the extraversion/introversion and the rigidity/plasticity characteristics. Emotional excitability is orthogonally related to the complex.