Morphology of Neurons: Golgi Pictures

Abstract

As soon as the Golgi technique made it possible to stain individual neurons in the tissue, dissecting them out, as it were, from the tangle of their intermingled processes, it became apparent that they come in a spectacular variety of shapes and sizes. The collection of illustrations in CajaPs Histologie (1911) together with further drawings only recently made available in a translation of CajaPs original papers (DeFelipe and Jones, 1988) furnishes a panorama of this variety to which more recent publications (see papers in Peters and Jones, 1984 a onward) have added comparatively little. What improved staining techniques have shown recently, however, particularly by means of dyes injected into the cell (Gilbert and Wiesel, 1979, and many others; see Parnavelas, 1984), is that the Golgi stain may occasionally leave part of the axonal tree unstained. We have already noted this when comparing our estimates of the axonal density obtained from Golgi pictures with those inferred by other means (Chap. 7). The general picture, however, has not changed much since Ca-jal and the old dilemma between an urge to differentiate neurons in an ever finer taxonomy, and the opposite urge to reduce the variety to a few simple categories is still with us today.