Parkinson’s disease is a progressive disorder of the nervous system that affects your movement. It develops gradually, sometimes starting with a barely noticeable tremor in just one hand. But while tremor may be the most well-known sign of Parkinson’s disease, the disorder also commonly causes stiffness or slowing of movement.

In early stages of Parkinson’s disease, your face may show little or no expression, or your arms may not swing when you walk. Your speech may become soft or slurred. Parkinson’s disease symptoms worsen as your condition progresses over time.

Although Parkinson’s disease can’t be cured, medications may markedly improve your symptoms.
Symptoms:
Tremor. Your tremor, or shaking, usually begins in your limb, often your hand or fingers. You may notice a back-and-forth rubbing of your thumb and forefinger, known as a pill-rolling tremor. One characteristic of Parkinson’s disease is tremor of your hand when it is relaxed (at rest).
Slowed movement (bradykinesia). Over time, Parkinson’s disease may reduce your ability to move and slow your movement. This may make simple tasks difficult and time-consuming. Your steps may become shorter when you walk, or you may find it difficult to get out of a chair. Also, your feet may stick to the floor as you try to walk, making it difficult to move.
Rigid muscles. Muscle stiffness may occur in any parts of your body. The stiff muscles can limit your range of motion and cause you pain.
Impaired posture and balance.
Loss of automatic movements. In Parkinson’s disease, you may have a decreased ability to perform unconscious movements, including blinking, smiling or swinging your arms when you walk. You may no longer gesture when talking.
Speech changes. You often may have speech problems as a result of Parkinson’s disease. You may speak softly, quickly, slur or hesitate before talking. Your speech may be more of a monotone, rather than with the usual inflections.
Writing changes

Medications typically markedly reduce many of these symptoms. These medications increase or substitute for a specific signaling chemical (neurotransmitter) in your brain: dopamine. People with Parkinson’s disease have low brain dopamine concentrations.

When to see a doctor
See your doctor if you have any of the symptoms associated with Parkinson’s disease — not only to diagnose your condition but also to rule out other causes for your symptoms.

Let’s watch a video about the Autonomic Nervous System: