Car accidents can take away a person’s ability to move by damaging the body’s internal lines of communication.
When electrical messages can no longer pass between the brain and muscles, the person is paralyzed.
But although movement is lost, the area of the brain generating it remains active, according to a study published in the Oct. 25 issue of the journal Nature.
It’s a discovery that may be a preliminary step toward allowing disabled people to regain mobility, said Richard Normann, a University of Utah bioengineering and ophthalmology professor and an author of the study.
The results of the recent study indicate that the area of the brain involved in shaking hands, dancing, throwing a baseball or kissing remains active, producing signals to instruct the muscles. The result indicated the activity remains for at least five years after an injury.
Hopefully, engineers can design methods for translating the brain’s signals into motions such as moving a cursor on a computer screen, turning a wheelchair or raising a robotic arm.
The discovery may provide the basis for developments that make it possible for people to stand up from a wheelchair and walk on their own?but that is far, far in the future, Normann said.
The study’s subjects had various degrees of paralysis, the results of injuries sustained from car accidents between one and five years before the study.
Normann hopes that devices could communicate the mental commands of people in the same condition to artificial devices.
Producing movement is a complex process. The motor cortex of the brain commands a muscle to move with a pattern of signals.
“We spend the first 10 years of our life learning how to produce firing patterns that produce appropriate muscle motions,” he said. “We go from being clumsy, somewhat spastic infants to being graceful adults.”
Researchers could potentially design ways to interpret the firing patterns and use them to manipulate mechanical devices, producing movement.
Normann has worked on an artificial vision system for the blind that uses a camera to relay information directly to the brain. He is also involved in research on a device to aid the deaf.
Ultimately, the goal of his work is to restore abilities to those who have lost them. Researchers approach this from two fronts?biological solutions, such as gene therapy, and engineered solutions like those he is working on.
Developments in both fields will be complementary, he said
Work on interfaces with the nervous system is not a new idea.
Pacemakers, which use electricity to stimulate an irregular heartbeat, appeared in the mid-20th century. Implants placed in an ear can allow the profoundly deaf to hear virtually everything, and electrical currents injected deep into the brain can soothe the tremors of Parkinson’s disease. These are spectacular achievements, he said.
Such interfaces could one day moderate epileptic seizures or help the disabled walk, he said.