Treatment that gets on your nerves

‘Neuromodulation’ is opening up new possibilities for medical therapies by seeking to target and change nerve activity

If something gets on your nerves you usually want to get rid of it as quickly as possible. But from a medical perspective, targeting nerves could offer ways to treat some movement and sensory conditions.

Your body contains a complex network of nerves, which are like electrical information highways, that plays an important role in how you sense the environment – and pain – and how and when parts of your body move.

“Neuromodulation”, which seeks to target and change nerve activity, is opening up new possibilities for medical therapies, according to Dr Ross O’Neill.

He’s CEO of MuteButton, which is developing ways to modulate nerves for the condition tinnitus, where a person “hears” phantom noises like ringing or buzzing. And O’Neill believes that devices are the way forward when looking to home in on nerve activity.

“Pharmaceutical interventions are neither spatially nor temporally targeted,” he says. “A drug blanket bombs the whole system – you don’t know how long it’s going to be in there, and how it acts depends on factors how big you are and how much you eat. With a device you can be much more targeted.”

Going deep into the brain

One way to change how nerves act is to implant electrodes into the brain. Deep-brain stimulation, or DBS, is a surgical therapy for a range of different disorders of the nervous system, explains Dr Madeleine Lowery, a senior lecturer at University College Dublin’s school of electrical, electronic and communications engineering.

“It involves surgically implanting electrodes into a region of the brain known as the basal ganglia – which is a part of the brain involved in movement – and it delivers a very high-frequency stimulus to neurons in that part of the brain,” she says.

“The electrodes are connected by means of a wire that runs just below the skin surface down into the chest cavity to a pulse generator, which looks similar to a standard cardiac pacemaker.”

DBS has been used to treat symptoms in people with movement disorders, such as Parkinson’s disease. You don’t have to look too hard online to find clips of patients whose tremors ease the moment the stimulation is turned on.

Yet the mechanism through which DBS works has yet to be fully understood. Funded through Science Foundation Ireland, Lowery and colleagues are now using computational models to look at how the electrical stimulation could be changing firing patterns in the brain, and how the approach could suppress oscillations that are causing problems. They also want to inform potentially “smarter” ways to go about it.