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Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York, USA; 3 Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York, USA Abstract: Patients with essential tremor (ET) have kinetic arm tremor; this tremor can also have an intentional com- ponent. We are unaware of reports of intention tremor of the head in ET. Our aims were to describe, provide elec- trophysiological data and video documentation of, and es- timate the prevalence of intention tremor of the head in our sample. Ten (9.0%; 95% confidence interval  4.7%–14.3%) of 111 patients had intention tremor of the head; in 7 it involved the neck and in 3 the chin. These patients trended toward having more severe kinetic arm tremor and they had more severe intention tremor of the arms. These observations provide further support for the evolving view that the cerebellum may be involved in ET. © 2006 Movement Disorder Society Key words: essential tremor; intention tremor; head tremor; cerebellum The predominant clinical finding in patients with essen- tial tremor (ET) is arm tremor. 1,2 This tremor is primarily a kinetic tremor but patients may also exhibit a postural tremor. 1,2 ET patients with longstanding disease may also develop a tremor at rest in their arms. 3,4 Finally, there is an intentional or terminal component to arm tremor in many ET patients (i.e., the tremor increases in amplitude at the endpoint of goal-directed movement such as finger-to-nose testing). 5 The presence of inten- tion tremor provides additional evidence, along with imaging studies, 6–8 electrophysiological studies, 5,9 –12 and case reports, 13 for the evolving view that the cere- bellum may be involved in the pathogenesis of ET. Tremor commonly affects other body regions besides the arms in ET patients, and postural tremor (tremor while seated or standing) may occur in the head in 34% to 53% of patients. 14 –18 We report another type of head tremor, intention tremor of the head, which is phenom- enologically distinct from postural head tremor and, to our knowledge, has not been described previously. We used the term “head tremor” to refer to tremor involving structures (e.g., the chin) that are part of the head or are connected to the head (e.g., the neck). Our two primary aims are to describe and provide video and electrophys- iological documentation of intention tremor of the head in patients with ET, and to estimate the prevalence of this tremor in our sample of ET patients. A secondary aim is to begin to explore some of the possible clinical corre- lates of this type of tremor. Our overarching goal is to provide further support for the accumulating literature that suggests that the cerebellum is involved in ET. 5,9 –12 PATIENTS AND METHODS ET patients are being recruited as potential brain do- nors to the Essential Tremor Centralized Brain Reposi- tory at Columbia University. 19 Participation in the pro- gram entails completion of demographic and medical questionnaires and creation of a videotaped tremor ex- This article includes Supplementary Video, available online at http:// www.interscience.wiley.com/jpages/0885-3185/suppmat *Correspondence to: Dr. Elan D. Louis, Unit 198, Neurological Institute, 710 West 168th Street, New York, NY 10032. E-mail: edl2@columbia.edu Received 29 March 2005; Revised 15 March 2006; Accepted 18 April 2006 Published online 7 September 2006 in Wiley InterScience (www. interscience.wiley.com). DOI: 10.1002/mds.21079 INTENTION TREMOR OF HEAD IN ET 2001 Movement Disorders, Vol. 21, No. 11, 2006