Spinal cord injuries are life-altering, as they prevent the transmission of nerve impulses past the point of injury. That means no sensory inputs make it to the brain, and no signals from the brain make it to the muscles normally controlled by the brain. But improvements in our understanding of neurobiology have raised the hope that we can eventually restore some control over paralyzed limbs.

Some of these efforts focus purely on nerve cells, attempting to get them to grow through the damage at the site of injury and restore a functional spinal cord. Others attempt to use electronics to bypass the injury entirely. Today, there was very good news for the electronics-focused effort: researchers have designed a spinal implant that can control the leg muscles of paralyzed individuals, allowing them to walk with assistance within hours of the implant being activated.

Skipping the brain

Much of the spinal cord is composed of long extensions made by nerve cells, termed axons. These axons allow nerve impulses to travel long distances, which is necessary for information to travel back and forth to the brain. Sensory inputs, like pain in your elbow or tickling of your feet, ride axons up the spinal cord into the brain. The brain in turn sends signals back down the spinal cord, controlling your breathing or moving your arms.