OBJECTIVES: Transcranial magnetic stimulation (TMS) was used to study intracortical inhibitory and excitatory phenomena in patients with cerebellar ataxia. METHODS: Motor evoked potentials (MEP) following single and paired TMS were recorded from the first dorsal interosseus muscle (FDI) in 15 patients with autosomal-dominant or idiopathic cerebellar ataxia and 15 age matched normal controls. RESULTS: MEP amplitudes after paired TMS with short interstimulus intervals (1-4 ms) showing intracortical inhibition in the control group were not significantly different in the patient group. In contrast, with longer interstimulus intervals (8-20 ms) mean MEP amplitudes were significantly reduced in the patient group, indicating a decrease of intracortical facilitation. The mean postexcitatory inhibition after TMS was also significantly prolonged in the patient group. CONCLUSION: Our findings support the idea that the cerebellum physiologically exerts a facilitatory influence on the motor cortex which is decreased in patients with a cerebellar degeneration.
OBJECTIVES: Transcranial magnetic stimulation (TMS) was used to study intracortical inhibitory and excitatory phenomena in patients with cerebellar ataxia. METHODS: Motor evoked potentials (MEP) following single and paired TMS were recorded from the first dorsal interosseus muscle (FDI) in 15 patients with autosomal-dominant or idiopathic cerebellar ataxia and 15 age matched normal controls. RESULTS: MEP amplitudes after paired TMS with short interstimulus intervals (1-4 ms) showing intracortical inhibition in the control group were not significantly different in the patient group. In contrast, with longer interstimulus intervals (8-20 ms) mean MEP amplitudes were significantly reduced in the patient group, indicating a decrease of intracortical facilitation. The mean postexcitatory inhibition after TMS was also significantly prolonged in the patient group. CONCLUSION: Our findings support the idea that the cerebellum physiologically exerts a facilitatory influence on the motor cortex which is decreased in patients with a cerebellar degeneration.
Authors: G Grimaldi; G P Argyropoulos; A Boehringer; P Celnik; M J Edwards; R Ferrucci; J M Galea; S J Groiss; K Hiraoka; P Kassavetis; E Lesage; M Manto; R C Miall; A Priori; A Sadnicka; Y Ugawa; U Ziemann Journal: Cerebellum Date: 2014-02 Impact factor: 3.847
Authors: Christos Ganos; Simone Zittel; Martina Minnerop; Odette Schunke; Christina Heinbokel; Christian Gerloff; Christine Zühlke; Peter Bauer; Thomas Klockgether; Alexander Münchau; Tobias Bäumer Journal: Cerebellum Date: 2014-02 Impact factor: 3.847
Authors: Tiago da Silva Lopes; Samir K Ballas; Jamille Evelyn Rodrigues Souza Santana; Pedro de Melo-Carneiro; Lilian Becerra de Oliveira; Katia Nunes Sá; Larissa Conceição Dias Lopes; Wellington Dos Santos Silva; Rita Lucena; Abrahão Fontes Baptista Journal: Front Med (Lausanne) Date: 2022-09-20