Essential Tremor (ET) is a neurological condition that causes shaking of the hands, head and voice, but it can also cause the legs and trunk to shake. Some people even have a feeling of internal tremor. The tremor begins mild and progresses over time to become more severe – and in some patients severe enough to interfere significantly with daily activities, such as eating, dressing, writing, etc. Essential tremor is associated with movement while doing actions and is not present at rest.
Essential Tremor is the most common movement disorder affecting an estimated 10 million Americans according to the International Essential Tremor Foundation. Essential tremor is more common in people age 40 and older, however many people may be diagnosed at an earlier age.
What Causes Essential Tremor?
The cause of essential tremor is still not fully understood, but it is thought that the abnormal electrical brain activity that causes tremor is processed through the thalamus. The thalamus is a structure deep in the brain that coordinates and controls muscle activity.
Years of previous surgical work has identified the Vim nucleus of the thalamus as the part of the brain to be treated in order to alleviate the tremor.
Essential tremor is generally an inherited condition. If you have a parent with a genetic mutation for essential tremor, you have a 50 percent chance of developing the disorder yourself.1
Although ET is more common in the elderly – and symptoms become more pronounced with age – it is not a part of the natural aging process.
The primary symptoms associated with essential tremor include:
- Uncontrollable shaking that occurs for brief periods of time
- Begins gradually, usually on one side of the body
- Occurs in the hands first, affecting one hand or both
- Can include a shaking voice or tremor of the head
- Nodding head
- Worsening during periods of emotional stress and purposeful movement
- Balance problems (in rare cases)