Neurogenesis as an organizing function of the adult brain: Is there enough evidence?

Аннотация

A half century of studying the neurogenesis of the adult brain has produced much evidence for an endogenous conversion of neural stem cells. Yet the idea receives increasing criticism, in addition to the many positive comments. Does neurogenesis proceed at a rate sufficiently high for its functional significance? Are new cells capable of integrating into proper brain regions in order to perform a reparative role? How long do new neurons persist in the integration sites, and how significant is their role in the neuronal circuit structure? An organizing function is hypothesized for endogenous adult brain neurogenesis on the basis of current information. One of the main arguments for the hypothesis is the multiplicity of key physiological processes functionally associated with the involvement of new neurons and glial cells: learning, memory, adaptive behavior, protective stress responses, reproductive function, changes in the state of mind, injuries, ischemic and neurodegenerative disorders, etc. The adjustable reprogramming of neuronal precursors and the reparative role of new cells are analyzed. The organizing role of neurogenesis is considered a justified complex process that is important for the function of the adult brain.