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Imagine the brain could reboot,

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updating its withered and damaged cells[br]with new, improved units.

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That may sound like science fiction,

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but it's a potential reality[br]scientists are investigating right now.

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Will our brains one day [br]be able to self-repair?

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It's well known that embryonic cells[br]in our young developing brains

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produce new neurons,

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the microscopic units [br]that make up the brain's tissue.

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Those newly generated neurons migrate[br]to various parts of the developing brain,

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making it self-organize [br]into different structures.

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But until recently,

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scientists thought cell production came to[br]an abrupt halt soon after this initial growth,

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leading them to conclude [br]that neurological diseases,

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like Alzheimer's and Parkinson's,

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and damaging events, like strokes,[br]are irreversible.

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But a series of recent discoveries

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has revealed that adult brains [br]actually do continue to produce new cells

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in at least three specialized locations.

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This process, known as neurogenesis,

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involves dedicated brain cells,[br]called neural stem cells

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and progenitor cells,

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which manufacture new neurons[br]or replace the old ones.

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The three regions where neurogenesis[br]has been discovered

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are the dentate gyrus,[br]associated with learning and memory,

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the subventricular zone, which may[br]supply neurons to the olfactory bulb

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for communication [br]between the nose and brain,

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and the striatum, [br]which helps manage movement.

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Scientists don't yet have a good grasp[br]on exactly what role

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neurogenesis plays [br]in any of these regions,

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or why they have this ability [br]that's absent from the rest of the brain,

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but the mere presence of a mechanism[br]to grown new neurons in the adult brain

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opens up an amazing possibility.

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Could we harness that mechanism[br]to get the brain to heal its scars

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similar to how new skin[br]grows to patch up a wound,

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or a broken bone [br]stitches itself back together?

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So here's where we stand.

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Certain proteins and other small molecules[br]that mimick those proteins

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can be administered to the brain

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to make neural stem cells [br]and progenitor cells

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produce more neurons [br]in those three locations.

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This technique still needs improvement

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so that the cells [br]reproduce more efficiently

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and more cells survive.

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But research shows that progenitor cells[br]from these areas

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can actually migrate to places where[br]injury has occurred

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and give rise to new neurons there.

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And another promising possible approach

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is to transplant healthy [br]human neural stem cells,

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which are cultured in a laboratory,[br]to injured tissue,

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like we can do with skin.

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Scientists are currently experimenting

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to determine whether transplanted[br]donor cells can divide, differentiate

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and successfully give rise [br]to new neurons in a damaged brain.

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They've also discovered

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that we might be able to teach[br]other kinds of brain cells,

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such as astrocytes[br]or oligodendrocytes

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to behave like neural stem cells[br]and start generating neurons, too.

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So, a couple of decades from now[br]will our brains be able to self-repair?

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We can't say for sure,

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but that has become one of the major [br]goals of regenerative medicine.

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The human brain has 100 billion neurons

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and we're still figuring out the wiring[br]behind this huge biological motherboard.

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But everyday, research on neurogenesis[br]brings us closer to that reboot switch.