Tremor can be classified into two main categories:

Parkinsonian tremor

Parkinsonian tremor is a common symptom of Parkinson’s disease, although not all people with Parkinson’s disease have tremor. Generally, symptoms include shaking in one or both hands at rest. It may also affect the chin, lips, face, and legs. The tremor may initially appear in only one limb or on just one side of the body. As the disease progresses, it may spread to both sides of the body. The tremor is often made worse by stress or strong emotions. More than 25 percent of people with Parkinson’s disease also have an associated action tremor.

Resting tremor occurs when the muscle is relaxed, such as when the hands are resting on the lap.  With this disorder, a person’s hands, arms, or legs may shake even when they are at rest.  Often, the tremor only affects the hand or fingers.  This type of tremor is often seen in people with Parkinson’s disease and is called a “pillrolling” tremor because the circular finger and hand movements resemble rolling of small objects or pills in the hand. 

Action tremor

Action tremor occurs with the voluntary movement of a muscle. Most types of tremor are considered action tremor. There are several sub-classifications of action tremor, many of which overlap.

Most of the tremors I have experienced are Action tremors. Which means, they happen when I am actively trying to do something. All I need to do, to stop the tremor is to relax my hand, or leg, etc. The problem comes when I need to maintain a grip, because I am carrying something or lifting a utinsel toward my mouth, because if I relax it would result in a dropped item or spilled food. I have learned to use two hands when carrying items I would previously carried with one hand, and lay my fork down while I chew. I feel very fortunate that I am able to relax my feet, legs. arms, hands and even my chin/jaw with ease.

A tremor is most commonly classified by its appearance and cause or origin.  There are more than 20 types of tremor.  Since I don’t manifest very much resting tremors but have many non-motor symptoms, the Doctor ordered a datscan, to confirm I had a significant lose of dopamine… thus Parkinson’s instead of essential tremor

Essential tremor

Essential tremor (previously also called benign essential tremor or familial tremor) is one of the most common movement disorders.  The exact cause of essential tremor is unknown.  For some people this tremor is mild and remains stable for many years.  The tremor usually appears on both sides of the body, but is often noticed more in the dominant hand because it is an action tremor.

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