Journal
CLINICAL NEUROPHYSIOLOGY
Volume 132, Issue 8, Pages 1878-1886Publisher
ELSEVIER IRELAND LTD
DOI: 10.1016/j.clinph.2021.04.011
Keywords
rPDC; Corticomuscular coupling; Essential tremor; FCMTE; Tremor network
Categories
Funding
- NWO technology foundation STW [NeuroSIPE 10739]
Ask authors/readers for more resources
The study aimed to clarify the role of the motor cortex in tremor generation in essential tremor (ET) and familial cortical myoclonic tremor with epilepsy (FCMTE). The results showed that the majority of ET patients lacked a linear cortical drive, with weaker ascending coupling in ET compared to healthy controls around 5-6 Hz.
Objective: A role of the motor cortex in tremor generation in essential tremor (ET) is assumed, yet the directionality of corticomuscular coupling is unknown. Our aim is to clarify the role of the motor cortex. To this end we also study 'familial cortical myoclonic tremor with epilepsy' (FCMTE) and slow repetitive voluntary movements with a known cortical drive. Methods: Directionality of corticomuscular coupling (EEG-EMG) was studied with renormalized partial directed coherence (rPDC) during tremor in 25 ET patients, 25 healthy controls (mimicked) and in seven FCMTE patients; and during a self-paced 2 Hz task in eight ET patients and seven healthy controls. Results: Efferent coupling around tremor frequency was seen in 33% of ET patients, 45.5% of healthy controls, all FCMTE patients, and, around 2 Hz, in all ET patients and all healthy controls. Ascending coupling, seen in the majority of all participants, was weaker in ET than in healthy controls around 5-6 Hz. Conclusions: Possible explanations are that tremor in ET results from faulty subcortical output bypassing the motor cortex; rate-dependent transmission similar to generation of rhythmic movements; and/or faulty feedforward mechanism resulting from decreased afferent (sensory) coupling. Significance: A linear cortical drive is lacking in the majority of ET patients. (C) 2021 International Federation of Clinical Neurophysiology. Published by Elsevier B.V.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available