Several early-stage clinical trials indicate that implanting patients with the cells is safe. But whether they can alleviate neurological problems remains to be seen.

The machine cannot be used outside of the lab yet, but the results are promising.

Uncertainties about the cells’ risk profiles and the potential for hyping unproven therapies mean scientists and the media must tread carefully.

The treatment will be tested in a handful of patients who suffered nerve damage in sports or traffic accidents.

The eel-like lamprey can return to normal swimming and burrowing after suffering a severed spinal cord twice.

Precisely timed electrical stimulation and intensive rehabilitation restore some capacity to walk among three men more than four years after their debilitating injuries.

The first human experiment with neural precursor cells implanted to treat chronic spinal cord injury suggests the procedure is safe, and hints at a small benefit.  

Thousands of axons grew from the transplants and connected to damaged primate tissue, the first such demonstration in primates.

Zebrafish have a remarkable ability to heal their damaged nerve fibers following a spinal injury.