The Brain's Role in Parkinsonian Syndrome and Essential Tremor
All deliberate movement starts in the brain. When you want to move, chemicals in your brain begin a cascade of events that result in the stimulation of nerves and muscles that complete the action.
There are many types of movement disorders, and two of the most common are parkinsonian syndrome and essential tremor. If you would like to learn more about other types of movement disorders, Worldwide Awareness and Education for Movement Disorders is an excellent resource.
PS and ET movement disorders (also known as motor system disorders) are caused by changes to the parts of the brain that control muscle movement. People with PS or ET movement disorders may move less than they want to (freezing or getting stuck) or more than they want to (tremors or shaking). The changes in the brain that lead to PS or ET movement disorders are sometimes caused by side effects of medicine, an injury, or stroke. However, sometimes the cause of these changes is not known. It's important to know whether you have PS or ET in order to get the right treatment.
Some symptoms of PS and ET movement disorders are:
- Tremor (shaking)
- Slowness of movement (bradykinesia) or a shuffling walk
- Rigidity (stiffness)
- Postural instability (balance problems)
- Small, cramped handwriting
- Facial mask (stiff facial expression)
- Vocal symptoms (muffled speech, soft voice)
- Depression or moodiness
The role of dopamine
Parkinsonian syndrome (PS) movement disorders are caused by the loss of the brain cells that produce dopamine, a brain chemical. Dopamine has a role in many functions of the body, including the control of movement. When the brain does not produce enough dopamine, it can result in a collection of symptoms known as parkinsonian syndromes (PS). The most common of the PS conditions is Parkinson's disease.
Not all movement disorders are caused by too little dopamine. Essential tremor (ET) is a condition that shares some of the symptoms found in PS. It is not yet known what part of the brain is responsible for ET. Essential tremor, the most common form of movement disorder in the elderly, is sometimes misdiagnosed as PS.
Next: The Differences Between PS and ET