Dendritic and spinal alterations of the spiny stellate cells of the human visual cortex during normal aging.

The visual cortex undergoes age related changes that have been studied mainly in rats Maccaca Mulata, and human beings. Despite the fact that there is no extensive neuronal loss in aged brains, a lot of important pathological changes are found in the morphology of the neurons. The present study describes the morphological alterations of the spiny stel-late cells of the human primary visual cortex during normal aging, using Golgi method, Golgi-Nissl staining and Nissl staining. Two types of spiny stellate cells have been studied. the first one located at layer 4Cβ and the second one located at layer 4Cβ. Even if some spiny stel-late cells retain high number of primary dendrites in the aged group there seems to be important spine loss, and extensive dendrite pathology. Age-related changes were more significant in spiny stellate cells of layer 4Cβ. Dendritic and spinal alterations described in the present study could explain the decline in visual functions during normal aging.