The histopathologic diagnosis of the senile psychoses with dementia is based mainly on the silver stains. The major points of differential diagnosis, clinical and pathologic, are summarized in a table (table 1) based on the data contained in the literature, as well as on our own experience. The literature has recently been reviewed by Grünthal,1 von Braunmühl2 and Alexander.3 Though the senile plaques appear to be rather specific for the senile dementias, especially those of the Alzheimer group, neurofibrillar changes, most of them of slightly dissimilar morphologic character but of similar staining properties (hyperargyrophilia), as in the senile neurofibrillar changes of Alzheimer type, have been observed in other diseases of the central nervous system, such as dementia paralytica (Bielschowsky and Brodmann4), chronic epidemic encephalitis (Hallervorden5), paralysis agitans (Lewy6),
spastic spinal paralysis (Barrett7 and Schaffer8), amyotrophic lateral sclerosis (van Bogaert and Bertrand9