In writing our book we had in mind both practicing physicians and scientif- ic personnel. We hope that the former will benefit from an analysis of clinical symptoms and changes in the morphological substrate which produce them, and that the latter will be interested in facts illustrating the resistance of nervous tissue to compression and displacement, and in our concept of the primary role played by blood supply in the functional disturbances of a deformed brain stem. Although only a short time has elapsed since the first edition of the book, it has been necessary to introduce a number of...