Developmental growth of the human neostriatum during fetal stages

Introduction. The neostriatum is a large subcortical brain area that includes the caudate nucleus and putamen and plays a crucial role in motor function. There are few studies on the development of the human neostriatum in the prenatal period, which makes it difficult to understand the morphogenesis of this region. The aim of this study was to investigate the volumes of the caudate and putamen in order to understand the normal development of the neostriatum during fetal stages. Materials and methods. The volumes of the caudate nucleus and putamen were measured on serial sections of the brains of 8 human fetuses between weeks 12 and 30 of gestational development. The sections were histologically stained. Results. Between weeks 12 and 30 of gestation, the caudate nucleus and putamen volumes increased by more than 400 and 250 times, respectively. These data are comparable to the results obtained using both classical histological methods and modern noninvasive imaging techniques. This similarity is likely to be due to high density of neuroblasts in the neostriatum during fetal development, which eliminates artifacts associated with sample dehydration. Conclusion. The rapid rate of neurogenesis in the neostriatum during human prenatal development indicates the crucial importance of motor development. Accumulating data on the normal development of the caudate nucleus and putamen could contribute to early diagnosis of motor disorders. Keywords: caudate nucleus, putamen, basal ganglia, human brain development