"Organic" and "functional" diseases of the nervous system

The aim of this paper is to discuss whether in the realm of diseases of the nervous system the concept of "dysfunctional" versus "organic" disorders is still useful. The knowledge on the Common Brain Stem System (CBSS) described by Hess is reviewed in order to underline its role as a control centre integrating all the homeostatic and adaptive nervous activities, and in this context, the nervous control of the cardiovascular system is examined, particularly in relation to higher nervous activities. The neurogenic syncopes are chosen as examples of the either "organic" or "dysfunctional" conditions whose semeiotic and pathophysiological distinctive features are analysed. In conclusion the distinction between "organic" diseases and "dysfunctional" disorders seems to be still justified, mainly for the nervous affections involving the homeostatic-adaptive properties of the CBSS.