Fourty-one cases have been studied, using the research of 10 brain stem reflexes, leading to define 6 levels of axial disturbances. The anatomical post-mortem findings allowed the authors to assume that primary brain stem damages are scarcely found (4 p. 100), as compared with diffuse brain damage (93 p. 100). The amount of supratentorial diffuse lesions seems to be the most important factor to determine the level of axial disturbance: the larger supra-tentorial lesion the lower brain stem dysfunction level. The authors emphasize the special value of corneo-pterygoidal reflex as a borderline in the rostro-caudal deterioration process of theCNS, following severe head injury.