Parkinson’s disease is a degenerative disorder with no known cure. But doctors and patients now have more tools to fight the progression of the disease than ever before.

We asked several leading doctors questions about the disease, diagnosis factors, and treatments. Read their answers below.

If you suspect you might be at risk for Parkinson’s disease, at what point should you see a neurologist?

According to neurologist Dr. Lawrence Severt, people should think about seeing a neurologist if they “notice a cluster of symptoms, for instance, if they are having trouble using their hands and/or if they notice changes in their balance or walking. If a person is experiencing asymmetric symptoms, such as a tremor or stiffness only on one side of the body or more on one side than the other, that is also a sign to consult with either a neurologist or a movement disorder specialist.”

What happens in the brain of a person with Parkinson’s?

“There’s a very small part of the brain, less than half an inch at the very base, and it makes a chemical called dopamine,” says neurologist Dr. Samuel Frank. “That part of the brain degenerates over time — sometimes over many years or decades. Before people present with symptoms, they lose the ability to make the neurotransmitter called dopamine. We’re not 100 percent sure of all the functions of dopamine, but we know that it controls movement.”

How fast does Parkinson’s disease progress?

“One of the challenges of PD is how quickly or slowly it progresses in different people. Parkinson’s is a different disease in every person,” explains Dr. Frank. “We don’t know why some people with PD progress faster than others, even though there are specific forms of the disease that we think may progress more quickly. In general, though, progression takes years, even decades. Usually people have experienced symptoms for a year or two before they get diagnosed. There are other signs that are potential early indicators of a PD diagnosis, too, such as loss of smell, constipation, depression, and anxiety. Those are pre-motor symptoms that can show up years before any type of tremor. Many people can live — and live well — with PD for many decades.”

Can anything be done to stall the progression of symptoms?

Neurologist Dr. Edward Wolpow says that “exercising regularly and vigorously” may lessen or stall symptoms, but not the progression of the disease. He also suggests that patients “exercise regularly in order to build up their strength, balance, and endurance because they will need it later.”

Why is exercise so important?

Exercise isn’t only good for you physically, but mentally too. Research shows that people with Parkinson’s who are in good health score better on cognitive and muscle control tests.

What about mental exercising?

“Regular cognitive exercise like doing crossword puzzles, math problems, reading challenging novels, socializing, and interacting with friends and debating and discussing ideas is already showing promise in many studies that focus on decreasing a person’s risk for degenerative neurological disease, including PD,” says Dr. Severt.

What do people go through after they’re diagnosed with Parkinson’s?

“Everyone has a different reaction, a sort of grief response, a whole mix of emotions,” says health psychologist Dr. John Allen. “It’s hard to integrate. Sometimes people have the reaction that they want to maximize their living potential. Most people are frustrated. There’s also an acceptance process. Every time there’s a loss of ability, there is a genuine grieving process. It’s a loss of independence. Those changes can be subtle, but they can also be very depressing.”

Why do doctors believe people with Parkinson’s disease start to lose dopamine?

“There are some theories,” says Dr. Frank. “Head trauma is one of the emerging theories, as is exposure to pesticides, herbicides, and/or heavy metals. Many epidemiologic studies are currently under way that are studying why these brain cells die off.”

How is Parkinson’s disease treated?

“We actually have a lot of options to treat PD,” continues Dr. Frank. “Unfortunately there’s no way to slow the progression of the disease that we know of right now. There are some hints that certain compounds might work, but right now we are essentially only treating the symptoms of the disease. Most of that treatment is focused around replacing dopamine with levodopa, or L-dopa [Sinemet]. There are other medications that mimic the actions of dopamine or make the action of existing dopamine more efficient.”

What about brain surgery or Deep Brain Stimulation (DBS)?

“In the early stages of PD, patients often respond well to medication, so brain surgery would be an unnecessary risk,” explains Dr. Bryan T. Klassen, assistant professor of neurology at the Mayo Clinic in Rochester, Minnesota. “In the middle stages, medications continue to be helpful but patients can suffer from motor fluctuations and dyskinesia [involuntary movements]. Because DBS can improve tremor, muscle stiffness, slow movements, and many walking problems with fewer fluctuations and dyskinesia, this therapy is best suited for patients in the middle stages.”

Who is a good candidate for DBS?

According to neurologist Dr. Jeff M. Bronstein, “good candidates for DBS are those PD patients who do not have significant cognitive or psychiatric problems. They must also have motor fluctuations and tremors that do not respond well to medications. While DBS can improve levodopa-response symptoms, dyskinesia, and tremor, benefits seem to be long-lasting in many [areas] of the brain.

What are the risks of DBS?

Besides the obvious risks of any surgery, such as bleeding or infection, “a small number of patients who undergo DBS may experience increased depression, apathy, impulsivity, worsened verbal fluency, and executive dysfunction,” continues Dr. Bronstein.

What about DBS treatment for late-stage Parkinson’s?

“In later stages of PD, patients may develop symptoms that will not respond to DBS, such as cognitive problems, imbalance, or problems with the autonomic nervous system,” says Dr. Klassen.