Daneault et al. Journal of Medical Case Reports 2011, 5:449 http://www.jmedicalcasereports.com/content/5/1/449 throughout the trials. The unchanged EMG signal con- firms that the recorded displacement in the fourth trial is still PT and not that our patient was swaying their right hand. As for the unchanged heart rate and respira- tion, this indicates a focal event, and not a generalized change in our patient’s state. These results further point to the localized epileptic activity as a cause of the observed changes in PT. Finally, we should stress that although changes in tre- mor characteristics have been observed with the use of anti-epileptic drugs (see [13], for example), the phenom- enon observed here is quite distinct. Indeed, our patient presented with PT within normal parameters in the first trial, and although modifications of those characteristics were observed from the second to the last trial, they never entered what could be considered a pathological state. In fact, pathological tremors usually have an amplitude of more than 4 to 5 mm, with a power dis- persion of less than three, such as seen in Parkinson’s disease [9] or Essential tremor [10]. While the current protocol does not allow the deter- mination of whether the changes in PT were pre-ictal or ictal, it delivers interesting information about the mechanisms of PT and perhaps into possible monitoring methods. Indeed, as PT was the only measured physio- logical signal modified by the epileptiform activity, which was localized to the somatosensory cortex, this can argue for a possible involvement of this cortical area in the central network generating PT. In addition, since changes in PT, although very slight, were observed prior to our patient’s usual pre-ictal signs, we can hypothesize that the structures involved in the PT cortical network are hypersensitive to abnormal oscillations. Of course, studies using EEG on patients having similar types of seizures are required to confirm this hypothesis. Also, if these observed changes were in fact pre-ictal, it could lead to the development of novel, simple and inexpensive devices able to be used for long periods of time. These could be capable of alerting individuals to an upcoming seizure before any conscious symptoms occur when an EEG is not readily available or impracti- cal [14]. Again, further research is needed to determine the feasibility and practicality of such devices. Conclusions Changes in physiological tremor characteristics should now be considered as another possible pre-ictal or ictal manifestation. Consent Written informed consent was obtained from the patient for publication of this case report and any accompanying Page 5 of 6 images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Acknowledgements The authors wish to thank our patient, who volunteered her time for this study. This research was funded by a Natural Science and Engineering Research Council of Canada through a Master’s scholarship (BC), Undergraduate Student Research Award (MR) and operating grant (CD) as well as a Fonds de Recherche en Santé du Québec Doctoral scholarship (J- FD). CD is also supported by a Fonds de Recherche en Santé du Québec salary grant. Author details 1Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Quebec, Canada. 2Département de Sciences Biologiques, Université du Québec à Montréal, Montréal, Québec, Canada. 3Département de Kinanthropologie, Université du Québec à Montréal, Montréal, Québec, Canada. Authors’ contributions J-FD created the protocol, analyzed and interpreted the data from our patient regarding tremor and electromyography, and was a major contributor in writing the manuscript. BC elaborated the protocol, analyzed and interpreted the data from our patient regarding tremor and electromyography, and was a major contributor in writing the manuscript. MR interpreted the data from our patient regarding tremor and electromyography. CD interpreted the data from our patient regarding tremor and electromyography, and was a major contributor in writing the manuscript. All authors read and approved the final manuscript. Competing interests The authors declare that they have no competing interests. Received: 28 April 2011 Accepted: 12 September 2011 Published: 12 September 2011 References 1. Fisher RS, van Emde Boas W, Blume W, Elger C, Genton P, Lee P, Engel J Jr: Epileptic seizures and epilepsy: definitions proposed by the International League Against Epilepsy (ILAE) and the International Bureau for Epilepsy (IBE). Epilepsia 2005, 46:470-472. 2. Gastaut H: Clinical and electroencephalographical classification of epileptic seizures. Epilepsia 1970, 11:102-113. 3. 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