title: The role of the ipsilateral primary motor cortex in movement control after spinal cord injury: a TMS study.
abstract: Previous neuroimaging studies raised the hypothesis that enhanced activity in the ipsilateral motor cortex (M1) plays a contributing role in the compensation for the motor deficits resulting from a spinal cord injury (SCI). However, it is still unknown whether the activity in the ipsilateral M1 directly contributes to movement performance after SCI. To address this question, we evaluated in five subjects with chronic incomplete cervical SCI the effects of suprathreshold transcranial magnetic stimulation (TMS) to both hemispheres when a movement of the right and left hand was performed separately in the setting of a simple reaction time. We found that stimulation of each hemisphere resulted in delayed simple reaction times in the contralateral but not in the ipsilateral hand. These observations provide the first direct evidence in humans that the ipsilateral M1 did not contribute significantly to motor task performance after SCI.
authors.affiliation: Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, 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.forename: Yvonne
authors.initials: Y
authors.lastname: Höller
authors.forename: Peter
authors.initials: P
authors.lastname: Höller
authors.forename: Natasha
authors.initials: N
authors.lastname: Thon
authors.forename: Aljoscha
authors.initials: A
authors.lastname: Thomschewski
authors.forename: Francesco
authors.initials: F
authors.lastname: Brigo
authors.forename: Eugen
authors.initials: E
authors.lastname: Trinka
mesh_terms: D000328:Adult; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006225:Hand / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D050781:Transcranial Magnetic Stimulation
keywords: Ipsilateral motor cortex; Motor cortex; Reaction time; Spinal cord injury; Transcranial magnetic stimulation