Via EurekAlert: "In mice, after a stroke was initiated in a part of the brain located far from the [subventricular zone], the researchers [tracked] newly formed neuroblasts (immature brain cells from which mature adult neurons form) as they traveled through healthy brain tissue to the stroke area. Once there, these immature neurons wrapped themselves around the immature vascular cells that were in the process of forming new blood vessels in the damaged area. ... two proteins, stromal-derived factor 1 (SDF1) and angiopoietin 1 (Ang1), that are given off by these newly-forming blood vessels, are what trigger the thousands of immature neurons to the site of damage. ... the molecular mechanisms for neuronal regeneration hold the promise of regenerating and reconnecting brain cells near the area where stroke occurs." When scientists understand the mechanisms and signals by which the brain repairs itself, the door is opened to greatly improving the effectiveness of these processes - very much a needed advance.