Skip to main content Accessibility help
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 1
  • Print publication year: 2009
  • Online publication date: December 2009

27 - Tremor



Tremor is defined as a “… rhythmical, involuntary oscillatory movement of a body part …” (Deuschl et al., 1998). These involuntary movements can easily affect the voluntary movements of reaching and grasping up to the total loss of control in patients with severe tremor disorders. The following chapter will review the clinical characteristics and pathophysiological concepts of the most frequent and pathophysiologically important tremor disorders and link the findings to the control of grasping and other hand functions.

Physiological tremor

Clinical characteristics

Any movement or isometric contraction is accompanied by the mostly invisible normal physiological tremor. The limits between normal and pathological tremors can be difficult to define. A pragmatic clinical approach is to define abnormal tremor whenever it is visible to the naked eye. The frequency of physiological tremor is usually greater than 7–8 Hz. It has recently been proposed that any tremor at lower frequencies is likely to be pathological (Elbe et al., 2005), but in cases of gradual transitions this clinical criterion can be problematic.


Theoretically tremor oscillations can emerge from two basic mechanisms. Any movable limb can be regarded as a pendulum with the capability to swing rhythmically (oscillate). These oscillations will automatically assume the resonant frequency of this limb which is dependent on its mechanical properties; the greater its weight the lower its resonant frequency, the greater the joint stiffness the higher its frequency (Elbe & Randall, 1978; Lakie et al.,1986). Any mechanical perturbation can activate such an oscillation.

Related content

Powered by UNSILO
Bergeron, M., Reader, T. A., Layrargues, G. P. & Butterworth, R. F. (1989). Monoamines and metabolites in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy. Neurochem Res, 14, 853–859.
Brown, P. (2000). Cortical drives to human muscle: the Piper and related rhythms. Prog Neurobiol, 60, 97–108.
Butterworth, R. F. (2000). Complications of cirrhosis. III. Hepatic encephalopathy. J Hepatol, 32, 171–180.
Conn, H. O. (1993). Hepatic encephalopathy. In Schiff, B. & Schiff, E. R. (Eds.), Diseases of the Liver (pp. 1036–1060). Philadelphia, PA: Lippincott.
Conway, B. A., Halliday, D. M., Farmer, S. al. (1995). Synchronization between motor cortex and spinal motoneuronal pool during the performance of a maintained motor task in man. J Physiol (Lond), 489, 917–924.
Deuschl, G., Bain, P. & Brin, M. (1998). Consensus statement of the Movement Disorder Society on Tremor. Ad Hoc Scientific Committee. Mov Disord, 13 (Suppl. 3), 2–23.
Deuschl, G., Wilms, H., Krack, P., Wurker, M. & Heiss, W. D. (1999). Function of the cerebellum in Parkinsonian rest tremor and Holmes' tremor. Ann Neurol, 46, 126–128.
Deuschl, G., Wenzelburger, R., Loffler, K., Raethjen, J. & Stolze, H. (2000). Essential tremor and cerebellar dysfunction clinical and kinematic analysis of intention tremor. Brain, 123 (Pt. 8), 1568–1580.
Elble, R. J. & Randall, J. E. (1978). Mechanistic components of normal hand tremor. Electroencephalogr Clin Neurophysiol, 44, 72–82.
Elble, R. J., Higgins, C. & Elble, S. (2005). Electrophysiologic transition from physiologic tremor to essential tremor. Mov Disord, 20, 1038–1042.
Findley, L. J., Gresty, M. A. & Halmagyi, G. M. (1981). Tremor, the cogwheel phenomenon and clonus in Parkinson's disease. J Neurol Neurosurg Psychiatry, 44, 534–546.
Gross, J., Tass, P. A., Salenius, al. (2000). Cortico-muscular synchronization during isometric muscle contraction in humans as revealed by magnetoencephalography. J Physiol, 527, 623–631.
Haussinger, D., Laubenberger, J., vom Dahl, al. (1994). Proton magnetic resonance spectroscopy studies on human brain myo-inositol in hypo-osmolarity and hepatic encephalopathy. Gastroenterology, 107, 1475–1480.
Heimer, G., Rivlin-Etzion, M., Bar-Gad, al. (2006). Dopamine replacement therapy does not restore the full spectrum of normal pallidal activity in the 1-methy-4-phenyl-1,2,3,6-tetra-hydropyridine primate model of Parkinsonism. J Neurosci, 26, 8101–8114.
Hurtado, J. M., Gray, C. M., Tamas, L. B. & Sigvardt, K. A. (1999). Dynamics of tremor-related oscillations in the human globus pallidus: a single case study. Proc Natl Acad Sci USA, 96, 1674–1679.
Hurtado, J. M., Lachaux, J. P., Beckley, D. J., Gray, C. M. & Sigvardt, K. A. (2000). Inter- and intralimb oscillator coupling in parkinsonian tremor. Mov Disord, 15, 683–691.
Joebges, E. M., Heidemann, M., Schimke, al. (2003). Bradykinesia in minimal hepatic encephalopathy is due to disturbances in movement initiation. J Hepatol, 38, 273–280.
Kircheis, G., Wettstein, M., Timmermann, L., Schnitzler, A. & Haussinger, D. (2002). Critical flicker frequency for quantification of low-grade hepatic encephalopathy. Hepatology, 35, 357–366.
Lakie, M., Walsh, E. G. & Wright, G. W. (1986). Passive mechanical properties of the wrist and physiological tremor. J Neurol Neurosurg Psychiatry, 49, 669–676.
Lang, A. E. & Lozano, A. M. (1998). Parkinson's disease. Second of two parts. N Engl J Med, 339, 1130–1143.
Leavitt, S. & Tyler, H. R. (1964). Studies in asterixis. Arch Neurol, 10, 360–368.
Liu, X., Ford-Dunn, H. L., Hayward, G. al. (2002). The oscillatory activity in the Parkinsonian subthalamic nucleus investigated using the macro-electrodes for deep brain stimulation. Clin Neurophysiol, 113, 1667–1672.
Mousseau, D. D., Perney, P., Layrargues, G. P. & Butterworth, R. F. (1993). Selective loss of pallidal dopamine D2 receptor density in hepatic encephalopathy. Neurosci Lett, 162, 192–196.
Mousseau, D. D., Baker, G. B. & Butterworth, R. F. (1997). Increased density of catalytic sites and expression of brain monoamine oxidase A in humans with hepatic encephalopathy. J Neurochem, 68, 1200–1208.
Nolano, M., Guardascione, M. A., Amitrano, al. (1997). Cortico-spinal pathways and inhibitory mechanisms in hepatic encephalopathy. Electroencephalogr Clin Neurophysiol, 105, 72–78.
Pollok, B., Gross, J., Dirks, M., Timmermann, L. & Schnitzler, A. (2004). The cerebral oscillatory network of voluntary tremor. J Physiol, 554, 871–878.
Raethjen, J., Lindemann, M., Schmaljohann, al., (2000a). Multiple oscillators are causing parkinsonian and essential tremor. Mov Disord, 15, 84–94.
Raethjen, J., Pawlas, F., Lindemann, M., Wenzelburger, R. & Deuschl, G. (2000b). Determinants of physiologic tremor in a large normal population. Clin Neurophysiol, 111, 1825–1837.
Raethjen, J., Pohle, S., Govindan, R. al. (2005). Parkinsonian action tremor: interference with object manipulation and lacking levodopa response. Exp Neurol, 194, 151–160.
Salenius, S., Portin, K., Kajola, M., Salmelin, R. & Hari, R. (1997). Cortical control of human motoneuron firing during isometric contraction. J Neurophysiol, 77, 3401–3405.
Schnitzler, A., Gross, J. & Timmermann, L. (2000). Synchronised oscillations of the human sensorimotor cortex. Acta Neurobiol Exp, 60, 271–287.
Sturman, M. M., Vaillancourt, D. E., Metman, L. V., Bakay, R. A. & Corcos, D. M. (2004). Effects of subthalamic nucleus stimulation and medication on resting and postural tremor in Parkinson's disease. Brain, 127, 2131–2143.
Tass, P., Rosenblum, M. G., Weule, al. (1998). Detection of n:m phase locking from noisy data: Application to magnetoencephalography. Phys Rev Lett, 81, 3291–3294.
Timmer, J., Lauk, M., Pfleger, W. & Deuschl, G. (1998). Cross-spectral analysis of physiological tremor and muscle activity. I. Theory and application to unsynchronized electromyogram. Biol Cybern 78, 349–357.
Timmermann, L., Gross, J., Kircheis, G., Haussinger, D. & Schnitzler, A. (2002). Cortical origin of mini-asterixis in hepatic encephalopathy. Neurology, 58, 295–298.
Timmermann, L., Gross, J., Butz, al. (2003a). Mini-asterixis in hepatic encephalopathy induced by pathologic thalamo-motor-cortical coupling. Neurology, 61, 689–692.
Timmermann, L., Gross, J., Dirks, al. (2003b). The cerebral oscillatory network of parkinsonian resting tremor. Brain, 126, 199–212.
Timmermann, L., Butz, M., Gross, al. (2005). Neural synchronization in hepatic encephalopathy. Metab Brain Dis, 20, 337–346.
Timmermann, L., Florin, E. & Reck, C. (2007). Pathological cerebral oscillatory activity in Parkinson's disease: a critical review on methods, data and hypotheses. Expert Rev Med Devices, 4, 651–661.
Timmermann, L., Butz, M., Gross, al. (2008). Impaired cerebral oscillatory processing in hepatic encephalopathy. Clin Neurophysiol, 119, 265–272.
Volkmann, J. (1998). Oscillations of the human sensorimotor system as revealed by magnetoencephalography. Mov Disord, 13, 73–76.
Wang, S. Y., Aziz, T. Z., Stein, J. F. & Liu, X. (2005). Time-frequency analysis of transient neuromuscular events: dynamic changes in activity of the subthalamic nucleus and forearm muscles related to the intermittent resting tremor. J Neurosci Meth, 145, 151–158.
Wenzelburger, R., Raethjen, J., Loffler, al. (2000). Kinetic tremor in a reach-to-grasp movement in Parkinson's disease. Mov Disord, 15, 1084–1094.
Yang, S. S., Chu, N. S. & Liaw, Y. F. (1985). Somatosensory evoked potentials in hepatic encephalopathy. Gastroenterology, 89, 625–630.
Yang, S. S., Wu, C. H., Chiang, T. R. & Chen, D. S. (1998). Somatosensory evoked potentials in subclinical portosystemic encephalopathy: a comparison with psychometric tests. Hepatology, 27, 357–361.
Young, R. R. & Shahani, B. T. (1986). Asterixis: one type of negative myoclonus. Adv Neurol, 43, 137–156.