Studies on the growth of the human nervous system: IV. Material illustrating the postnatal growth and topography of the basal nuclei

Abstract

TWO TEXT FIGURES AND ONE PLATERelatively little is published on the postnatal growth and topography of the basal nuclei of the human cerebrum, although Franceschi (quoted by Donaldson, 1895) has recorded some figures regarding their size in children and adults.l H. L. Dunn, in a study of the growth of the brain, sectioned and photographed twenty-five specimens of various ages. He has kindly allowed us to use twelve specimens of this series for a further illustrative study by reconstruction and graphic methods ; the results are presented here. METHODSThe material was prepared in the following way : All the specimens were fixed in a 10 per cent formalin solution for at least 6 months. Each brain was then placed in a mass of melon pulp and concentrated aqueous gelatin solution and the whole allowed to set over night. The matrix was 'Franceschi (1888) weighed the corpora striata and the optic thalami. His method of preparing this subdivision was to excise the basal ganglia with the cortex of the insula attached, and then to dissect away both the cortex and the white matter of the insula until the gray substance of the ganglia could be clearly seen. The weights of these masses given by Francesehi are about twice those of the nuclei obtained in this study. This may be explained by his inclusion of the white substance of the corpora striata. The relative increase in these massea as noted by Franceschi is about the same as that obtained in this study of the basal nuclei proper. 443 THE ANATOMICAL REOOED, VOL 64, NO. 4, AND SUPPLEMENT NO. 3