Adult Hippocampal Neurogenesis in the Human Brain: Updates, Challenges, and Perspectives

The existence of neurogenesis in the adult human hippocampus has been under considerable debate within the past three decades due to the diverging conclusions originating mostly from immunohistochemistry studies. While some of these reports conclude that hippocampal neurogenesis in humans occurs throughout physiologic aging, others indicate that this phenomenon ends by early childhood. More recently, some groups have adopted next-generation sequencing technologies to characterize with more acuity the extent of this phenomenon in humans. Here, we review the current state of research on adult hippocampal neurogenesis in the human brain with an emphasis on the challenges and limitations of using immunohistochemistry and next-generation sequencing technologies for its study.