What Is Parkinson's Disease?

Ask most people to picture Parkinson's disease and they will picture a shaking hand. That picture isn't wrong, exactly — but it leaves out most of the story, and believing it is the whole story is the first myth worth setting aside.

The video above, "Pathophysiology of Parkinson's Disease," runs just under four minutes and explains what is actually happening underneath the symptoms. It describes Parkinson's as a common neurodegenerative condition that typically begins in the sixth or seventh decade of life, often starting with a resting tremor on one side, combined with varying degrees of stiffness and slowness. The condition takes its name from James Parkinson, who first described it in detail in the early nineteenth century.

Myth: it is only about tremor. Fact: movement changes in several ways

Tremor at rest — shaking that appears when the hand is still and eases when you reach for something — is only one part of the pattern. Slowness of movement, called bradykinesia, is just as central: everyday actions like buttoning a shirt or swinging your arms as you walk gradually take more effort. Muscles may feel stiff, steps can become shorter, and balance can be affected later on. Changes that have nothing to do with movement are common too, including a reduced sense of smell, sleep disturbance and low mood. In other words, if you are waiting for a tremor before taking symptoms seriously, you may be waiting for the wrong sign.

What is going wrong in the brain?

Deep in the brain, a small group of cells produces dopamine, a chemical messenger that helps coordinate smooth movement. In Parkinson's, those cells are gradually lost, and movement signals become harder to organise — which is why the symptoms are mainly about movement, at least at first. Why the cells are lost is still not fully understood, and for most people there is no single identifiable cause. That uncertainty can be frustrating, but it does not prevent treatment, because treatment works on the dopamine system and on the symptoms it produces.

How a diagnosis is reached

There is no single blood test or scan that settles it. A neurologist usually makes the diagnosis from the history and a careful examination — watching how you walk, how your arms swing, and how your muscles respond to gentle movement — sometimes supported by scans to rule out other causes. Because these signs overlap with other neurological conditions, an accurate diagnosis matters: our guide to epilepsy, for example, covers a very different condition that is also diagnosed mainly from history and examination. If your symptoms are changing, a specialist review is the right next step rather than self-diagnosis.

What treatment can — and cannot — do

Treatment does not yet stop the underlying cell loss, and it is honest to say so. What it can do, often very effectively, is ease symptoms and protect independence. Medicines that support dopamine signalling, such as levodopa, are a standard part of care, alongside physiotherapy, exercise, speech and occupational therapy tailored to the person. For some people with troublesome fluctuations later on, a surgical option called deep brain stimulation may be discussed — you can see how it works in this video from Vanderbilt Medical Center on deep brain stimulation, which uses an implanted neurostimulator to treat movement disorders including Parkinson's. Whether any of these options suit you is a decision for your own neurology team, made over time as the condition evolves.

Frequently Asked Questions

Does everyone with Parkinson's have a tremor?
No. Tremor is common, but some people mainly notice stiffness, slowness and balance problems, with little or no shaking.

What causes Parkinson's disease?
The symptoms come from the gradual loss of dopamine-producing cells in the brain. Why those cells are lost is not fully understood, and most cases have no single identifiable cause.

Is there a test for Parkinson's?
There is no single test. Diagnosis is usually clinical — based on your history and a neurological examination — sometimes with scans to exclude other causes.

Can Parkinson's be cured?
Not at present. Treatment focuses on easing symptoms and maintaining independence and quality of life, and care is adjusted over time by your own team.

MedicalVideos.com has published trusted medical videos since 2007. The site was founded by Dr. Mohamed Ibrahim, MD, PhD — physician and researcher.

Educational only — this article is general information about Parkinson's disease, not medical advice and not a diagnosis. If you are concerned about tremor, stiffness or slowness of movement, discuss it with your own doctor or neurologist.