Morphology of the developing visual cortex of the human infant: a quantitative and qualitative Golgi study.

A renaissance of the Golgi impregnation method has focused interest on dendritic aspects of neuronal development. The visual cortices of 39 "neurologically normal" infants from 14 weeks' gestation to 6 months of age were prepared at postmortem for rapid Golgi impregnation studies. These were stained and duplicated with camera lucida drawings. The total number of cells in defined columns of the visual cortex was counted on cresyl violet-stained sections, and differentiated neurons were identified. The number of spines on the apical and basal dendrites of selected cells was counted for a given interval along the dendrites. The camera lucida drawings, cell counts, and spine counts were used to illustrate the normal ontogeny of the visual cortex.