There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Eighty-three brains obtained at autopsy from nondemented and demented individuals
were examined for extracellular amyloid deposits and intraneuronal neurofibrillary
changes. The distribution pattern and packing density of amyloid deposits turned out
to be of limited significance for differentiation of neuropathological stages. Neurofibrillary
changes occurred in the form of neuritic plaques, neurofibrillary tangles and neuropil
threads. The distribution of neuritic plaques varied widely not only within architectonic
units but also from one individual to another. Neurofibrillary tangles and neuropil
threads, in contrast, exhibited a characteristic distribution pattern permitting the
differentiation of six stages. The first two stages were characterized by an either
mild or severe alteration of the transentorhinal layer Pre-alpha (transentorhinal
stages I-II). The two forms of limbic stages (stages III-IV) were marked by a conspicuous
affection of layer Pre-alpha in both transentorhinal region and proper entorhinal
cortex. In addition, there was mild involvement of the first Ammon's horn sector.
The hallmark of the two isocortical stages (stages V-VI) was the destruction of virtually
all isocortical association areas. The investigation showed that recognition of the
six stages required qualitative evaluation of only a few key preparations.