title: Modulation of non-painful phantom sensation in subjects with spinal cord injury by means of rTMS.
abstract: We aimed in this study to investigate whether repetitive transcranial magnetic stimulation (rTMS), given as theta burst stimulation (TBS), can interfere with non-painful phantom sensations in subjects with spinal cord injury (SCI). In double-blind, sham-controlled experiments in five subjects with cervical or thoracic traumatic SCI, we evaluated the effects of a single session of inhibitory (continuous) TBS, excitatory (intermittent) TBS, or placebo TBS, on simplex and complex non-painful phantom sensations. The interventions targeted the contralateral primary motor cortex (M1), the primary sensory cortex (S1) and the posterior parietal cortex (PPC). Measurements were carried out at baseline (T0), 5 min (T1) and 30 min later (T2) after the intervention. Descriptive evaluation of results shows that non-painful phantom sensations were not affected by rTMS applied over M1. Continuous (inhibitory) TBS over S1 induced a short-lasting decrease of simple non-painful phantom sensations, while continuous TBS over PPC induced a short-lasting decrease of both simple and complex phantom sensations. Intermittent (excitatory) TBS over PPC induced a slight increase of non-painful phantom sensations. Tests for significance confirm these observations, but must be interpreted with caution because of the small sample size. In conclusion, non-painful phantom sensations may be associated to a hyperexcitability of PPC and to a lesser extent of S1, which can be normalized by inhibitory rTMS. Our preliminary findings provide further evidence that neuromodulatory techniques are able to reverse phantom sensations not only after limb amputation but also in other conditions characterized by deafferentation such as SCI.
authors.affiliation: Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University and Center for Cognitive Neuroscience, Salzburg, Austria; Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria. Electronic address: raffaele.nardone@asbmeran-o.it.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Nardone
authors.affiliation: Department of Mathematics, Paris Lodron University of Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Langthaler
authors.affiliation: Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University and Center for Cognitive Neuroscience, Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Höller
authors.affiliation: Department of Mathematics, Paris Lodron University of Salzburg, Austria.
authors.forename: Arne
authors.initials: A
authors.lastname: Bathke
authors.affiliation: Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University and Center for Cognitive Neuroscience, Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Vanessa N
authors.initials: VN
authors.lastname: Frey
authors.affiliation: Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Department of Neurological, Neuropsychological, Morphological and Movement Sciences, Section of Clinical Neurology, University of Verona, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Brigo
authors.affiliation: Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University and Center for Cognitive Neuroscience, Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Eugen
authors.initials: E
authors.lastname: Trinka
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology*; D010591:Phantom Limb / Q000503:physiopathology / Q000628:therapy*; D013003:Somatosensory Cortex / Q000502:physiology; D013119:Spinal Cord Injuries / Q000503:physiopathology / Q000628:therapy*; D013826:Theta Rhythm / Q000502:physiology; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
keywords: Phantom sensation; Posterior parietal cortex; Somatosensory cortex; Spinal cord injury; Theta burst stimulation