Wired reports on successful efforts to induce the regeneration of neurons in mice: "They induced the birth of new cells by killing nearby neurons in mice, which set off a cascade of events that led to stem cells, also called precursor cells, producing new neurons in the cerebral cortex. If scientists can turn this into a therapy for humans, it would mean that patients could literally heal themselves with stem cells already present in their brains." This initial methodology is not one that would be used in humans; the object here is to study the chemical signals and cellular processes involved. Once those can be replicated, the door is wide open for brain regeneration in humans - and therapies for neurodegenerative disorders like Parkinson's and Alzheimer's.

Link: http://www.wired.com/news/medtech/0,1286,65560,00.html?tw=wn_tophead_9