Progressive dendritic changes in aging human cortex

doi:10.1016/0014-4886(75)90072-2

Experimental Neurology

Volume 47, Issue 3, June 1975, Pages 392-403

https://doi.org/10.1016/0014-4886(75)90072-2 Get rights and content

Abstract

The methods of Golgi have been used in the histological evaluation of brain tissue from ten aged patients with and without evidences of senility. A sequence of changes, identified particularly in third layer pyramids in prefrontal and superior temporal cortex, was seen with variable frequency in all aged brains. The intensity of changes noted appeared more a function of the amount of senile change shown by the patient, than of his calendar age. The sequence of histopathological changes involved increasing swelling and lumpiness in outline of the cell body and proximal dendrites, progressive loss of horizontally oriented dendrite systems, especially the basilar shafts, and eventual loss of apical shafts with cell death. Special significance was attached to the loss of horizontal dendrite masses for two reasons: (i) they have been shown to receive, selectively, synaptic terminals from intracortically derived fiber systems and (ii) their densely intertwined and bundled configurations have been proposed as storage sites for central programs. Preferential loss of this dendrite system seems likely to remove, progressively, the more subtle, modulatory aspects of cortical activity, along with a number of essential output programs coded along their surfaces. Deterioration of psychomotor performance with aging may accordingly be conceived in significant degree as a function of the quality of neuropil as well as of the amount of total nerve cell loss.

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¹: This study was supported by USPHS Grants NS 10567 and CHD 10468. We thank Abe Green for his help in preparation of the histological material.

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Progressive dendritic changes in aging human cortex

Abstract

J. Comp. Neurol.

Exp. Neurol.

Exp. Neurol.

Exp. Neurol.

Int. J. Neurosci.

Exp. Neurol.

Nisslazheim. Arb.

Ueber eine eigenartige Erkrankung der Hirnrinde

Cbl. Nervenheilk Psychiat.

Sur les lésions et la pathologie de l'epilepsie dite essentiale

Sem. Med. Paris

Age changes in the neuronal microenvironment

Aging of the vertebrate brain

Aging of the nervous system