**1. Introduction**

Two decades ago it was discovered that the adult mammalian brain contains neural stem cells (NSCs) and neural precursor cells (NPCs) capable of producing new neurons and glial cells [1-3]. This has led to a great deal of research to understand the biology of these cells and to determine signalling pathways that can be targeted to promote repair of the dam‐ aged nervous system. There are two primary regions in the adult mammalian brain that contain adult NSCs/NPCs. These are the subventricular zone (SVZ) lining the lateral walls of the lateral ventricles and the subgranular zone (SGZ) of the hippocampal dentate gyrus. NPC fate is regulated by intrinsic (e.g. transcription factors and signalling mediators) and extrinsic (e.g growth factors and extracellular matrix) factors which involve effects on prolif‐ eration, migration and differentiation of new neurons and glial cells.

This review will highlight the major signalling cascades involved in neuronal fate from birth to integration. It will begin with a discussion of pathways involved under normal physio‐ logical conditions, which will be followed by discussion of changes to these signalling cas‐ cades following neural damage due to injury or disease. Finally, there will be a more focused examination of the roles of suppressor of cytokine signalling (SOCS) molecules and related pathways in the context of signalling in adult neurogenesis under basal conditions and following neural damage.

© 2013 S. Basrai et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 S. Basrai et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
