ABSTRACT
INTRODUCTIONTremor is the most common neurologic movement disorder. Tremor is an oscillation of a body part produced by alternating or simultaneous contraction of agonist and antagonist muscles. This movement is usually rhythmic and regular and can affect one or more body parts, including the limbs, neck, chin, tongue, or vocal cords. This chapter will address tremor in general with an emphasis on Essential Tremor (ET). Chapter 5 focuses on tremor associated with Parkinson’s disease (PD). CLASSIFICATION OF TREMOR
Tremor can be described by the body part or parts affected, the etiology, or the frequency or oscillation of the tremor. The rate or frequency of tremor is usually expressed in Hertz (Hz) with one Hz equaling one oscillation or cycle per second. Tremors are usefully and broadly classified as occurring at rest or in action.
