From the brain’s perspective, muscle control is a highly complex task—whether crossing a tightrope, sending a wink across the room or simply sitting still. Even raising an eyebrow requires the cooperation of dozens of muscles we don’t even realize we have. Dystonia, which literally means “abnormal tonicity of muscle,” happens when the part of the brain that controls muscle movement is impaired. Involuntary muscle spasms force affected parts of the body into contorted or twisted postures. These spasms can strike anywhere––arms and legs, the face, vocal cords, the torso, neck and even eyelids. While dystonia is not a fatal condition, it is chronic and often painful and can be profoundly debilitating.

Dystonic symptoms can show up in childhood or adulthood, and they range from relatively minor movements to severe contortions or fixed postures. The condition rarely goes away completely, and predicting its course can be difficult.

There are two categories of dystonia: “primary” and “secondary.” Primary dystonias have a genetic source and simply appear, while secondary forms follow an injury or physical trauma such as stroke, poisoning, reactions to certain drugs or lack of oxygen at birth.

Dystonia is the third most prevalent movement disorder, behind Parkinson’s disease and tremor. More than 300,000 people in North America suffer with dystonia, and yet relatively little is known about why it occurs, primarily because unlike other neurological disorders, brain scans of dystonic patients look normal. Because cognitive abilities, intelligence, vision, hearing and muscle strength are all normal too, scientists have few clues as to the underlying mechanisms of the disease.

Causes of Dystonia

Today, research suggests that genetic factors are even more linked to developing dystonia than previously thought. Investigators are looking into whether a person whose dystonia occurs after an injury may have been genetically predisposed to developing the disease. Research also points to genetic causes for aberrations in dopamine, a brain chemical that influences motor control and becomes depleted in patients with dystonia.

Additional insights into the causes of dystonia have come from studying the region in the brain where motor function occurs. Called the “basal ganglia,” or “basement structures,” this region, located deep below the cerebral cortex, is where the messages that control muscle movement are processed. Investigators believe that damage to the basal ganglia can result in the type of involuntary movements that define dystonia.

Scientists also suspect that sensory functions, which influence motor movement, may offer clues. In TWISTED, Pat Brogan demonstrated how just placing his hands on his forehead and cheek neutralized his painful contortions. Though the reasons behind this are mysterious, similar sensory tricks provide relief for other types of dystonia. For example, pressure on the eyelids has improved eye spasms, placing a toothpick in the mouth can relieve tongue dystonia, and touching parts of the arm can relieve cramping hands.

The Link to Parkinson’s Disease

Scientists first became interested in the relationship between dopamine and dystonia back the 1950s and 1960s when another movement disorder, Parkinson's disease, was shown to cause depleted dopamine in the brain. More recently, researchers discovered that two altered genes were related to a rare form of “dopa-responsive” dystonia, which is triggered by exercise.

Dystonia is often compared to Parkinson's disease because both are movement disorders related to the basal ganglia part of the brain, and because symptoms of Parkinson's sometimes resemble the twisting of dystonia, though this is usually because of medications, not the disease. Dystonia patients sometimes show symptoms resembling late stage Parkinson’s disease, such as difficulty swallowing, moving slowly or vocal problems.

But despite these obvious connections, investigators have yet to find the shared structural link that might explain dystonia. They have located the structure within the basal ganglia that Parkinson's disease affects, called the substantia nigra, but the geography of dystonia remains largely unmapped.

Treating Dystonia

There are three categories of dystonia treatment: oral medications, Botox injections and deep brain stimulation (DBS) surgery. Of the three, surgery is the most risky. However, for those who have found no relief through other treatments, surgery holds the most hope. Unlike medications or injections, which offer only temporary relief, DBS can be a long-term solution. And unlike surgical treatments of the past, which destroyed parts of the brain, DBS only disrupts certain areas, and the treatment can be reversed or discontinued without causing permanent effects.

Deep Brain Stimulation

What is deep brain stimulation? The short answer is, a “pacemaker” for the brain. During DBS surgery a thin lead with four electrodes at the tip is inserted into the thalamus area of the brain. The lead is connected to an extension wire through a small opening in the skull. That extension wire connects to a battery operated pulse generator (the “pacemaker”) that is implanted near the collarbone. The device is set to continuously generate mild electrical stimulation that suppresses dystonic movements by blocking the brain signals that cause the contortions.

In TWISTED, Remy Campbell dramatically demonstrated the effectiveness of her deep brain stimulator when she turned it off for the cameras. Immediately she began to arch and bend forward, moving from an upright posture to a 45-degree angle, just moments after the stimulator was shut off.

Managing Dystonia

For most people suffering with dystonia, managing symptoms and pain is the primary goal. Finding the right balance of treatments—which can be explored individually or in combination—is often a long process that can take an emotional and physical toll.

For this reason, supplemental strategies can be very helpful, such as physical therapy, support groups and speech therapy. Meanwhile, the research goes on. Genetic links and dopamine changes seem to be the most promising beacons along the path to the ultimate goal—finding a cure for dystonia.

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