Tremors are involuntary, rhythmic shaking movements that occur in one or more parts of the body. They are most common in the hands, but they can also affect the arms, head, voice, torso, and legs. Tremors are most prevalent among middle-aged and older individuals, although they can occur at any age. Some tremors are inherited and can run in families. The most common form of tremor, essential tremor, is marked by involuntary shaking which tends to worsen over time.

Essential tremor is often observed in the hands, head, and voice and can range from mild to severe. It may start in one limb or on one side of the body and then spread to the other side. While the exact cause of essential tremor is not known, it is thought to be a neurological condition involving a disruption in the normal communication between certain areas of the brain, including the cerebellum.

Unlike the cerebrum, cerebellar disease causes problems on the SAME SIDE of the body as the cerebellar lesion. Titubation, which refers to the tremor of the head (and sometimes trunk), is a result of cerebellar disease. Parkinsonian tremor, which is different from essential tremor, is the most common cause of a resting tremor and usually involves the distal muscles, such as the hand.

A person with essential tremor may exhibit a postural hand tremor or an intention tremor, which is a shaking that worsens with movement and is less noticeable at rest. This type of tremor can be particularly disabling as it can interfere with daily activities and tasks.

Treatment for tremors may include medication to help control the shaking or surgical interventions, such as deep brain stimulation. This two-step surgery involves implanting permanent electrodes in the brain and a neurostimulator device under the skin, which can help silence the tremors with electrical pulses.

For more information on tremors and their management, visit the Stanford 25, Brain Institute at OHSU, and Harvard Health websites.