Schematic illustration of adult neurogenesis in the adult rodent and human brain.

<p>New neurons are indicated in green. (A) Neuroblasts that are generated in the subventricular zone lining the lateral ventricle (LV) in rodents migrate to the OB, a structure crucial for olfaction, where they integrate as interneurons. (B) Neuroblasts are present in the subventricular zone also in humans, and new neurons integrate in the adjacent striatum, which plays an essential role in movement coordination, procedural learning, and memory, as well as motivational and emotional control. New neurons are continuously generated in the DG of the hippocampus—a brain structure essential for memory and mood control—in both rodents and humans (A, B). A limited subpopulation of DG neurons are subject to exchange in rodents (C), whereas the majority turn over in humans (D) [<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002045#pbio.1002045.ref004" target="_blank">4</a>–<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1002045#pbio.1002045.ref006" target="_blank">6</a>]. The neurons within the turning over population are continuously exchanged. A value of 100% on the <i>y</i>-axis means that all neurons have been replaced since the individual’s birth.