Changes in Spinal Excitability After PAS

• Published in: Journal of neurophysiology 2007-04, Vol.97 (4), p.3131-3135
• Main Authors: Meunier, Sabine, Russmann, Heike, Simonetta-Moreau, Marion, Hallett, Mark
• Format: Article
• Language: English
• Subjects: Adult; Animal biology; Electric Stimulation; Evoked Potentials, Motor; Evoked Potentials, Motor - physiology; H-Reflex; H-Reflex - physiology; Hand; Hand - innervation; Hand - physiology; Humans; Life Sciences; Median Nerve; Median Nerve - physiology; Middle Aged; Muscle, Skeletal; Muscle, Skeletal - innervation; Muscle, Skeletal - physiology; Pilot Projects; Recruitment, Neurophysiological; Recruitment, Neurophysiological - physiology; Spine; Spine - physiology; Transcranial Magnetic Stimulation; Veterinary medicine and animal Health; Wrist; Wrist - innervation; Wrist - physiology
• ISSN: 0022-3077; 1522-1598
• DOI: 10.1152/jn.01086.2006

1 Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland; 2 Institut National de la Santé et de la Recherche Médicale (INSERM), U731, Paris, France; 3 Université Pierre et Marie Curie-Paris 6, Unité Mixte de Recherche S731, Paris, France; and 4 INSERM, U 825, Toulouse F-31059 France, Hôpital Purpan, Fédération de Neurologie, Toulouse, France Submitted 11 October 2006; accepted in final form 19 January 2007 Repetitive pairing of a peripheral stimulation with a magnetic transcortical stimulation (PAS) is widely used to induce plastic changes in the human motor cortex noninvasively. Based on the contrast between PAS-induced increase of corticospinal excitability and absence of PAS-induced increase of the spinal F wave size, it has been generally accepted that PAS-induced plasticity is cortical in origin. Here, instead of F waves, we used H reflex recruitment curves to assess spinal excitability, and we demonstrate that PAS induces parallel changes in cortical and spinal excitability. Address for reprint requests and other correspondence: S. Meunier, INSERM U731/UPMC, Service de Réadaptation Fonctionnelle, Hôpital de la Salpêtrière, 47 Bd de l'Hôpital, 75651 Paris Cedex 13, France (E-mail: meunier.sabine{at}free.fr )