In essential or familial tremor, the movement disorder is the only aspect of the disease. The only difference between essential tremor and familial tremor is that in the latter, there is a family history with tremor being present in other generations, whereas in essential tremor, there is not. The actual tremor itself is identical in both conditions.

In essential or familial tremor, the hands and arms are usually quiet at rest, but if the patient attempts to perform a task, such as picking up a glass of water or writing, then the tremor becomes very noticeable. Tremor can sometimes involve the head and neck and also sometimes involves the legs. Tremor interferes with many normal activities.  

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