What is an Essential Tremor?
Essential Tremor
Essential tremor is a nervous system disorder that causes rhythmic shaking you can’t control. It most often affects the hands, sometimes the head, and can affect almost any part of the body. The tremor usually gets worse with movement, such as tying your shoes or lifting a glass. Essential tremor usually isn’t dangerous, but it can become disabling as it progresses, and it is sometimes confused with Parkinson’s disease. It can begin at any age but is most common after age 40 (1).
How Common Is Essential Tremor?
Essential tremor is the most common movement disorder, affecting an estimated 7 million people in the United States. It becomes more common with age, and more than 4% of people over age 40 have essential tremor (2).
What Are the Early Signs of Essential Tremor?
Early signs of essential tremor include rhythmic shaking that develops gradually, usually starting in the hands. The tremor is usually worse with movement and minimal at rest. It typically affects both hands, though one side may be worse than the other. It can also cause a “yes-yes” or “no-no” motion of the head, and it can affect the voice, jaw or tongue. Fatigue, caffeine, low blood sugar, illness, emotional stress and temperature extremes can make it worse.
People may also notice a tremor when holding a position against gravity, such as holding the arms out in front of them, called postural tremor, or a feeling of shakiness inside the body (2). Some people have mild trouble with balance and coordination while walking, especially when walking heel to toe.
What Are the Later Signs of Essential Tremor?
Over time, the tremor may become larger and more disruptive to daily life. It may spread to both hands, move up the arms or affect the head. In some people, tremor may also appear at rest. Other symptoms can develop as well, including problems with thinking, changes in sense of smell, depression and anxiety (2). Essential tremor can also take a social and emotional toll, and some people begin avoiding social or stressful situations out of embarrassment or frustration.
What Causes Essential Tremor?
The cause of essential tremor is not fully understood. In many people, it runs in families, while others have no family history. First-degree relatives of a person with essential tremor are almost five times more likely than the general population to develop it (3).
In families where essential tremor is inherited, each child of an affected parent often has about a 50% chance of inheriting it. Researchers are still working to identify the specific genes involved (4).
Recent research suggests that essential tremor may be a neurodegenerative disorder that affects important cells in the cerebellum called Purkinje cells (5).
What Happens in the Brain With Essential Tremor?
Although essential tremor is the most common movement disorder, much remains unknown about what happens in the brain. Studies of the brain after death have found that Purkinje cells, cerebellar cells that help prevent excessive movement, may be breaking down in essential tremor. Researchers believe genetics likely play a role, but the genes involved have not yet been identified (6).
Essential tremor may also involve circuits connected to the basal ganglia (7). These circuits act like the gas and brake pedals of the movement system, helping start and stop movements. Like the cerebellum, they rely heavily on a calming brain chemical called GABA.
How Is Essential Tremor Diagnosed?
Essential tremor is diagnosed by a physician. They will take your medical history and do a physical and neurological exam, looking at when the tremor occurs (at rest or with movement), where it occurs, and asking about your symptoms. They may also check your balance, speech and muscle tone. Additional tests may include blood and urine tests to look for treatable causes, such as thyroid problems or medication effects; MRI of the brain to look for other causes; and electromyography (EMG) to measure muscle activity (8).
How Is Essential Tremor Usually Treated?
People with mild essential tremor may not need treatment. When tremor interferes with daily life or causes significant distress, medication is usually the first treatment (9). Common medications include propranolol and primidone.
Purkinje cells in the cerebellum use GABA to fine-tune movement and hold back unwanted movement, which may help explain why medications that boost GABA activity can reduce tremor in some people (5).
Botulinum toxin (Botox) injections may help with head and voice tremor when other medications haven’t worked (2). Because the effects wear off over time, repeat treatments are needed.
When medication and Botox aren’t enough, deep brain stimulation (DBS) of the thalamus may be an option. DBS involves surgically placing a thin wire in the brain, connected to a small, pacemaker-like device under the skin of the chest. Stimulation is adjusted from outside the body with a programmer. Many people experience significant relief from tremor after DBS (10). Another option for some people is focused ultrasound, which treats a small target in the thalamus without open surgery.
How the NeuroRescue Program Can Help
We cannot cure essential tremor. Our goal is to help improve the function of the systems involved, with a focus on tremor control, balance, daily function and quality of life. Our care works alongside your neurologist and other providers, never in place of them. Please don’t change any medication without talking with your prescriber.
Eye movements. Vision is our most developed sense, and the many types of eye movements we make depend on large parts of the cortex, deeper brain structures, the cerebellum and the brainstem. Changes in these areas can show up as changes in eye movements (11).
To move through the world, your brain first needs to know where things are. Saccades, the quick jumps the eyes make from one object to another, help take in your surroundings quickly. They need to be fast, accurate and quick to start. Because saccades depend on the cerebellum and other brain regions involved in essential tremor, they can be affected as well (12). We use targeted saccade exercises with the goal of improving the function of these brain regions and supporting tremor control.
Complex movement training. Depending on your needs, your program may include visual and vestibular rehabilitation to engage the cerebellum and deeper brain regions (13), along with complex movement tasks using the affected limbs to engage cerebellar pathways (14). The cerebellum works by predicting movements, then fine-tuning them in real time (15). Practicing and progressing complex movements is designed to help the cerebellum filter and smooth movement more effectively.
Other therapies. Your program may also include electrical stimulation, applied through the skin, which has been studied for supporting eye movements, balance and other sensory and motor functions (16), and virtual reality exercises, which one preliminary study explored for reducing tremor and improving coordination (17). Transcranial magnetic stimulation has been studied for tremor (18), and at our clinic it is provided by our psychiatric mental health nurse practitioner, who will evaluate whether it’s appropriate for you.
Every NeuroRescue Program is different, with therapies chosen based on your testing and your specific situation.
How the NeuroRescue Program Works
Your NeuroRescue Program begins with your Discovery Day. We start with a detailed history of your condition and your life on a timeline. This helps us understand the factors that may have contributed to where you are now, and identify related conditions that may be making it harder to move forward.
We measure how your visual, vestibular and balance systems are working through computerized analysis of your eye movements, inner ear reflexes and balance under different conditions. Our testing includes videonystagmography and saccadometry to measure several types of eye movements, the video head impulse test to measure inner ear reflexes, and CAPS computerized posturography to assess your balance under different sensory conditions. We also use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and your perception of vertical in a virtual reality environment.
We combine this with a thorough physical and neurological exam of your sensory, motor, autonomic and cognitive systems. We also review any relevant lab work, imaging and prior testing, and integrate it with our findings.
Together, this helps us understand which parts of your nervous system are working well, which are struggling, and how quickly they tire. We use that information to design your personal NeuroRescue Program, aimed at improving function and endurance in the systems that need support. Our testing also helps us decide when to push and when to let you rest.
Our goal is to help you gain more control over your movements, feel more confident in daily activities, and enjoy more of your life.
Your Next Step
Living with essential tremor can be challenging. While we cannot cure it, symptoms can often be managed, and function and quality of life can often improve. To find out if the NeuroRescue Program is right for you, contact one of our patient care coordinators to schedule your Discovery Day.
It’s never too late to take the next step.
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