Some brain cells, in very select parts of the brain, do reproduce. Scientists discovered adult neurons in the hippocampus and ventricles of the brain are capable of cellular mitosis and transformation from progenitor cells, shattering the dogma that the number of adult neurons in the brain is fixed after birth.
Neurons in the brain, for the most part, do not further divide once the brain matures. Studies, however, have confirmed the ability of select brain cells to undergo cellular division. Scientists are studying these cells to better understand how the process of neurogenesis works, in hopes to eventually program other dormant brain cells to begin cell division. Other cells that make up the brain besides neurons include support cells such as astrocytes and oligodendrocytes. These support cells are able to undergo cell division to some degree as well.