Stefan J Groiss1,2, Hitoshi Mochizuki1,3, Ritsuko Hanajima4, Carlos Trenado2, Setsu Nakatani-Enomoto1, Koji Otani5, Yoshikazu Ugawa1,6. 1. a Department of Neurology, Faculty of Medicine , Fukushima Medical University , Fukushima , Japan. 2. b Department of Neurology & Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty , Heinrich-Heine-University , Düsseldorf , Germany. 3. c Division of Neurology, Respirology, Endocrinology and Metabolism, Department of Internal Medicine , University of Miyazaki , Miyazaki , Japan. 4. d Department of Neurology , Kitasato University School of Medicine , Sagamihara , Japan. 5. e Department of Orthopedic Surgery, Faculty of Medicine , Fukushima Medical University , Fukushima , Japan , and. 6. f Neurology , Fukushima Global Medical Science Center, Advanced Clinical Research Center, Fukushima Medical University , Fukushima , Japan.
Abstract
OBJECTIVES: The triad conditioned facilitation (TCF) technique has been shown to detect motor cortical intrinsic rhythms depending on the functioning of specific cortical layers by measuring motor evoked potential (MEP) enhancement after a triad of conditioning TMS pulses at a certain interval. However, the influence of cortical degeneration on TCF is still undetermined. We therefore studied TCF in patients with amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder characterised by degeneration of the motor cortex. METHODS: Thirteen patients with ALS and 11 age-matched disease control patients with cervical myelopathy (CM) or radiculopathy (CR) participated in the study. We studied short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and TCF using the paired-pulse and triad conditioned TMS paradigm. RESULTS: TCF was significantly reduced in ALS patients compared to CM/CR patients, who had normal TCF. SICI and ICF did not differ between groups. CONCLUSION: The absence of TCF with preserved SICI and ICF suggests changes in the intrinsic rhythm generation within the motor cortex due to cortical neurodegeneration in ALS patients. In contrast, TCF was normal in patents with CM/CR in whom the motor cortical intrinsic circuits are not involved. This technique may be valuable to differentiate patients with ALS from those with CM/CR.
OBJECTIVES: The triad conditioned facilitation (TCF) technique has been shown to detect motor cortical intrinsic rhythms depending on the functioning of specific cortical layers by measuring motor evoked potential (MEP) enhancement after a triad of conditioning TMS pulses at a certain interval. However, the influence of cortical degeneration on TCF is still undetermined. We therefore studied TCF in patients with amyotrophic lateral sclerosis (ALS), a neurodegenerative disorder characterised by degeneration of the motor cortex. METHODS: Thirteen patients with ALS and 11 age-matched disease control patients with cervical myelopathy (CM) or radiculopathy (CR) participated in the study. We studied short-interval intracortical inhibition (SICI), intracortical facilitation (ICF) and TCF using the paired-pulse and triad conditioned TMS paradigm. RESULTS: TCF was significantly reduced in ALSpatients compared to CM/CRpatients, who had normal TCF. SICI and ICF did not differ between groups. CONCLUSION: The absence of TCF with preserved SICI and ICF suggests changes in the intrinsic rhythm generation within the motor cortex due to cortical neurodegeneration in ALSpatients. In contrast, TCF was normal in patents with CM/CR in whom the motor cortical intrinsic circuits are not involved. This technique may be valuable to differentiate patients with ALS from those with CM/CR.
Authors: Shady Safwat Hassan; Carlos Trenado; Tarek Ali Rageh; Alfons Schnitzler; Stefan Jun Groiss Journal: Exp Brain Res Date: 2020-04-22 Impact factor: 1.972
Authors: Petyo Nikolov; Johanna V Zimmermann; Shady S Hassan; Philipp Albrecht; Alfons Schnitzler; Stefan J Groiss Journal: Exp Brain Res Date: 2020-12-29 Impact factor: 1.972