Investigation of Motor Cortical Plasticity and Corticospinal Tract Diffusion Tensor Imaging in Patients with Parkinsons Disease and Essential Tremor.
Parkinson's disease (PD) and essential tremor (ET) are characterized with motor dysfunctions. Motor circuit dysfunctions can be complementarily investigated by paired associative stimulation (PAS)-induced long-term potentiation (LTP)-like plasticity and diffusion tensor imaging (DTI) of the corticospinal tract (CST). Three groups of twelve subjects with moderate severity PD, ET with intention tremor and healthy controls (HC) were studied. The primary motor cortex (M1) excitability, measured by motor evoked potential (MEP) amplitude and by short-interval and long-interval intracortical inhibition (SICI and LICI) was compared between the three groups before and after PAS. The DTI measures of fractional anisotropy (FA) and mean diffusivity (MD) were acquired. PAS effects and DTI data were simultaneously examined between groups. PAS increased MEP amplitude in HC but not in PD and ET. SICI and LICI were significantly reduced after PAS irrespective of groups. No significant differences of the mean FA and MD were found between groups. There was no significant correlation between the PAS effects and the DTI measures. Findings suggest that both PD and ET with intention tremor have impairment of the associative LTP-like corticospinal excitability change in M1. The microstructure of the CST is not relevant to the deficiency of M1 associative plasticity in PD and ET.
Neuroscience Laboratory, Department of Neurology, China Medical University Hospital, Taichung, Taiwan.|School of Medicine, Medical College, China Medical University, Taichung, Taiwan.|Graduate Institute of Neural and Cognitive Sciences, Medical College, China Medical University, Taichung, Taiwan.
Ming-Kuei
http://orcid.org/0000-0002-2768-4399
MK
Lu
Graduate Institute of Neural and Cognitive Sciences, Medical College, China Medical University, Taichung, Taiwan.|Department of Radiology, China Medical University Hospital, Taichung, Taiwan.
Chun-Ming
CM
Chen
Institute of Cognitive Neuroscience, National Central University, Zhongli, Taiwan.|Institute for Neural Computation, University of California San Diego, La Jolla, California, United States of America.
Jeng-Ren
JR
Duann
Department of Neurology & Stroke, and Hertie Institute for Clinical Brain Research, Eberhard-Karls-University, Tübingen, Germany.
Ulf
U
Ziemann
Neuroscience Laboratory, Department of Neurology, China Medical University Hospital, Taichung, Taiwan.|School of Medicine, Medical College, China Medical University, Taichung, Taiwan.|Graduate Institute of Neural and Cognitive Sciences, Medical College, China Medical University, Taichung, Taiwan.
Jui-Cheng
JC
Chen
School of Medicine, Medical College, China Medical University, Taichung, Taiwan.|Department of Neurosurgery, China Medical University Hospital, Taichung, Taiwan.
Shang-Ming
SM
Chiou
Neuroscience Laboratory, Department of Neurology, China Medical University Hospital, Taichung, Taiwan.|School of Medicine, Medical College, China Medical University, Taichung, Taiwan.|Graduate Institute of Neural and Cognitive Sciences, Medical College, China Medical University, Taichung, Taiwan.
Chon-Haw
CH
Tsai
D000368:Aged; D000704:Analysis of Variance; D003710:Demography; D056324:Diffusion Tensor Imaging / Q000379:methods*; D020329:Essential Tremor / Q000150:complications / Q000503:physiopathology*; D019054:Evoked Potentials, Motor / Q000502:physiology; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000503:physiopathology; D009044:Motor Cortex / Q000503:physiopathology*; D009473:Neuronal Plasticity / Q000502:physiology*; D010153:Paired-Associate Learning; D010300:Parkinson Disease / Q000503:physiopathology*; D011712:Pyramidal Tracts / Q000503:physiopathology*; D012684:Sensory Thresholds / Q000502:physiology; D050781:Transcranial Magnetic Stimulation