title: Abnormal short-latency synaptic plasticity in the motor cortex of subjects with Becker muscular dystrophy: a rTMS study.
abstract: We used repetitive transcranial magnetic stimulation (rTMS) to further investigate motor cortex excitability in 13 patients with Becker muscular dystrophy (BMD), six of them with slight mental retardation. RTMS delivered at 5Hz frequency and suprathreshold intensity progressively increases the size of motor evoked potentials (MEPs) in healthy subjects; the rTMS-induced facilitation of MEPs was significantly reduced in the BMD patients mentally retarded or classified as borderline when compared with age-matched control subjects and the BMD patients with normal intelligence. The increase in the duration of the cortical silent period was similar in both patient groups and controls. These findings suggest an altered cortical short-term synaptic plasticity in glutamate-dependent excitatory circuits within the motor cortex in BMD patients with intellectual disabilities. RTMS studies may shed new light on the physiological mechanisms of cortical involvement in dystrophinopathies.
authors.affiliation: Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; TMS & fMRI Lab, Department of Neurology, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria. Electronic address: s.golaszewski@salk.at.
authors.forename: Stefan
authors.initials: S
authors.lastname: Golaszewski
authors.affiliation: Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; TMS & fMRI Lab, Department of Neurology, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Schwenker
authors.affiliation: Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bergmann
authors.affiliation: Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Department of Neurological, Neuropsychological, Morphological and Movement Sciences, University of Verona, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Brigo
authors.affiliation: Department of Physiology, Medical University of Graz, Graz, Austria.
authors.forename: Monica
authors.initials: M
authors.lastname: Christova
authors.affiliation: Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Eugen
authors.initials: E
authors.lastname: Trinka
authors.affiliation: Department of Neurology and Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria; Department of Neurology, Franz Tappeiner Hospital, Merano, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Nardone
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D019054:Evoked Potentials, Motor; D006801:Humans; D009044:Motor Cortex / Q000503:physiopathology*; D020388:Muscular Dystrophy, Duchenne / Q000503:physiopathology*; D009473:Neuronal Plasticity; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: Becker muscular dystrophy; Cortical plasticity; Cortical silent period; Dystrophinopathies; Glutamatergic transmission; Motor evoked potentials; Repetitive transcranial magnetic stimulation