BACKGROUND Harmaline-induced tremor in rodents has been extensively used as an animal model for essential tremor (ET). However, there is no visual documentation in the published literature. METHODS We injected mice subcutaneously with either 20 mg/kg of harmaline hydrochloride or saline and then videotaped the responses. RESULTS Action and postural tremor in the mouse began 5 minutes after ...

BACKGROUND Portable motion transducers, suitable for measuring tremor, are now available at a reasonable cost. The use of these transducers requires knowledge of their limitations and data analysis. The purpose of this review is to provide a practical overview and example software for using portable motion transducers in the quantification of tremor. METHODS Medline was searched via PubMed.go...

OBJECTIVES To examine the comparative reliability and validity of three simple ways of rating upper limb tremor in patients with multiple sclerosis. METHODS Three examiners independently rated severity of upper limb tremor in patients with multiple sclerosis on a 0-10 scale by studying videotape recordings of patients' examinations, spiral drawings, and handwriting samples. The correlations o...

Thalamomuscular coherence in essential tremor (ET) has consistently been detected in numerous neurophysiological studies. Thereby, spatial properties of coherence indicate a differentiated, somatotopic organization; so far, however, little attention has been paid to temporal aspects of this interdependency. Further insight into the relationship between tremor onset and the onset of coherence co...

BACKGROUND The re-emergent tremor of Parkinson's disease (PD) is generally recognized as a postural tremor. PHENOMENOLOGY SHOWN A PD patient with a re-emergent tremor occurring during a task (spiral drawing), which on the surface produced a tremor that resembled that of essential tremor (ET). EDUCATIONAL VALUE Researchers and clinicians should be aware of features of this re-emergent tremor...

Although cells firing at tremor frequency, called "tremor cells" (Guiot et al., 1962), have often been recorded in the thalamus of parkinsonian patients, the extent of correlation between these spike trains and tremor has rarely been assessed quantitatively. This paper describes spectral cross-correlation functions calculated between the activity of "tremor cells" and electromyogram (EMG) signa...

BACKGROUND Resting tremor is common in Parkinson's disease (PD), but up to 47% of PD patients have action tremor, which is sometimes resistant to medications. Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of the thalamus or subthalamic nucleus (STN) is effective for medication-refractory tremor in PD, though it remains unclear whether STN DBS is as effective as VIM DBS ...

See Vidailhet et al. (doi:10.1093/brain/awx140) for a scientific commentary on this article.Misdiagnosis among tremor syndromes is common, and can impact on both clinical care and research. To date no validated neurophysiological technique is available that has proven to have good classification performance, and the diagnostic gold standard is the clinical evaluation made by a movement disorder...

The effect of changes in mechanical limb properties on the peak frequency of different tremor forms was analysed. Wrist tremor was recorded by an accelerometer fixed to the dorsum of the hand and demodulated surface EMG was recorded from the wrist extensors, while the extended hand was loaded with successively heavier weights. Physiological tremor was characterised by flat EMG spectra and a gra...

Postural tremor occurs when the affected body part maintains position against gravity (e.g., extending arms in front of body). Isometric tremor results from muscle contraction against stationary objects (e.g., squeezing the examiner’s fingers). Kinetic tremor, which occurs with voluntary movement, is either simple kinetic tremor or intention tremor. Simple kinetic tremor is associated with move...