The present paper attempts to comment on the relation between diffuse concentric hyperostoses of the cranial vault and neurologic and psychiatric symptoms in a male aged 42 and a woman aged 23 when death occurred. In the past, similar discussions mainly concerned the hyperostosis frontalis interna (Hfi), although the demonstration of a true relation is difficult in the Hfi because of its late occurrence at an advanced age (60-70 years), in which mental disturbances due to other pathological circumstances are frequent as well. The diffuse concentric hyperostosis in young individuals has comparatively seldom been regarded, although in young individuals the age factor in the consideration of mental disturbances can be excluded. The 42 year old male had an 18 years history of mental disturbances such as a mental change and severe episodic psychiatric symptoms, which repeatedly required clinical treatment. Since 18 years he had also suffered from headaches which caused an abusus of phenacetinum. A diffuse concentric hyperostosis of the neurocranium with a long developmental course, as could be derived from microscopical examination, was considered likely to be the reason for the longstanding headaches and the mental change. The 23 year old female was a prostitute suffering from serious headaches and neurodystonia until she died suddenly and unexpectedly, without sufficient autopsy findings. The cranial vault displayed a severe concentric hyperostosis besides other striking changes.