The Brain as an Endocrine Organ

In the middle of the 17th century, the great French philosopher Rene Descartes wrote (L'Homme, J. Le Gras, Paris, 1669) that a suitable stimulation of the brain results in two types of "movements": exterior movements, designed to seek desirable ends and to avoid undesirable or harmful ones and interior movements or "passions" which through the release of "animal spirits" regulate the heart, the liver, and other organs. When it appears appropriate to meet a threat with force, the passion of ...