Question: why can we not repair damaged nerves in the brain?

Rebecca Dewey answered on 17 Jun 2015:

We can’t repair them with surgery because they are too fragile and we don’t have the materials needed to “patch them up”. Nerve cells can heal by themselves over time given the right conditions, the brain will have needed to adapt to working differently over this time. What the brain tends to do more often is find a new way of completing the task using different nerve cells. This is called plasticity, and is usually more beneficial than trying to heal the cell.