Customized Deep Brain Stimulation for a more efficient therapy of severe tremor

• Applicant: Dr. David Pedrosa
• Subject Area: Clinical Neurology; Neurosurgery and Neuroradiology
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 259395926

Tremor is one of the most common symptoms of different movement disorders. Its pathophysiology is suspected to pivot around exaggerated synchronisation within the human motor system with a complex interplay of different brain areas at cortical as well as at subcortical levels. The difficulty accessing the latter for electrophysiological recordings contributes to the limited number of studies regarding this interplay to date. In this context, thalamic recordings would be particularly desirable, as this brain region appears crucial for tremor generation. This significance is reflected as the ventrolateral thalamus constitutes one of the most important targets for therapeutical interventions for different forms of tremor. For instance, the application of electrical pulses within e.g. Deep Brain Stimulation (DBS) might successfully treat severely affected patients. Nevertheless, current forms of continuous thalamic stimulation suppressing tremor are linked to several stimulation-induced side-effects and a long-term loss of effect. This corroborates the need for establishing a better understanding of the underlying pathomechanisms of tremor and underlines the importance of the search for more efficient stimulation algorithms. Hence, this project is concerned with two different questions: first, the thalamic implantation of electrodes will be used for electrophysiological recordings. Combining electroencephalographic (EEG) with local field potential (LFP) measurements, we will analyse linear and non-linear interactions of remote brain areas. Particularly, the identification of biomarkers emerging before the onset of tremor will be of interest, as such markers could enable on-demand stimulation with less side-effects in a future. The second part of the project is designed to measure reduction of tremor amplitude with a novel stimulation algorithm. We will compare the reduction of tremor amplitude with pulses at low-frequency to effects during the established high-frequency DBS. The low frequency pulses will be coupled to the tremor phase enabling an adaptive and more efficient stimulation with a reduced number of pulses. Overall, this project is intended to combine basic science with a clinical study and aims at improving efficacy of therapeutic approaches for tremor in a future.

• DFG Programme: Research Fellowships
• International Connection: United Kingdom
• Host: Professor Dr. Peter Brown