Progressions on the Co-Existence of Neuronal and Glial Precursor Cells in the Cerebral Ventricular Zone.

Heterogeneity is defined as the quality or state of being diverse in character or content. This article summarizes the natural progression from my studies, reported in the first issue of the Journal of Neuroscience, that identified molecular heterogeneity in precursor cells of the developing primate cerebral cortex to the current state in which differences defined at the molecular, cellular, circuit and systems levels are building data encyclopedias. The emphasis on heterogeneity has impacted the field of developmental neuroscience and the many contributors who have led a quest to determine the extent to which there is diversity, when it appears developmentally, and the heritable and non-heritable factors that mediate nervous system assembly and function. Since the appearance of the article on progenitor cell heterogeneity in the inaugural issue of Journal of Neuroscience, there have been continuous advances in technologies and data analytics that are contributing to a much better understanding of the origins of neurobiological and behavioral heterogeneity.