|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL, USA
2 Department of Physical Therapy, University of Illinois at Chicago, Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, IL, USA
Magnetic stimulation of human primary motor cortex (M1) paired with electrical stimulation of a peripheral motor nerve has been used to produce a lasting modulation of corticomotor (CM) excitability. This paired associative stimulation (PAS) protocol has been used to induce bidirectional changes in excitability in upper limb CM pathways. The present study tested the hypothesis that temporally dependent PAS applied to the common peroneal nerve during the swing phase of walking would induce bidirectional changes in CM excitability consistent with the Hebbian principle of activity-dependent plasticity. Fourteen subjects with no known neurological disorder participated in two data collection sessions each. PAS was delivered as a single block of 120 pairs of stimuli delivered in a 10 min period during treadmill walking at 4.0 km h1. Changes in CM excitability were assessed by examining the size of motor potentials evoked by transcranial magnetic stimulation prior to and following PAS. Tibialis anterior motor-evoked potentials amplitude increased to 121% over baseline when the magnetic stimulus was delivered over M1 after the estimated arrival time of the afferent volley in sensorimotor cortex and decreased to 83% of baseline when the magnetic stimulus was delivered prior to the estimated afferent volley arrival. This extent of modulation was undiminished following a further 10 min period of walking without stimulation. The temporal nature of the bidirectional effects following PAS, their rapid evolution and subsequent persistence supported the study's hypothesis and were similar to the effects described by others in quiescent muscles of the upper limb.
(Received 16 May 2005;
accepted after revision 22 June 2005;
first published online 23 June 2005)
* Corresponding author J. W. Stinear: Sensory Motor Performance Program, 345 E. Superior St, Chicago, IL 60611, USA. Email: j-stinear{at}northwestern.edu
This article has been cited by other articles:
![]() |
X. Y. Chen, S. Pillai, Y. Chen, Y. Wang, L. Chen, J. S. Carp, and J. R. Wolpaw Spinal and Supraspinal Effects of Long-Term Stimulation of Sensorimotor Cortex in Rats J Neurophysiol, August 1, 2007; 98(2): 878 - 887. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. D. Roy, J. A. Norton, and M. A. Gorassini Role of Sustained Excitability of the Leg Motor Cortex After Transcranial Magnetic Stimulation in Associative Plasticity J Neurophysiol, August 1, 2007; 98(2): 657 - 667. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. R. Sheffler, M. T. Hennessey, G. G. Naples, and J. Chae Improvement in Functional Ambulation as a Therapeutic Effect of Peroneal Nerve Stimulation in Hemiplegia: Two Case Reports Neurorehabil Neural Repair, July 1, 2007; 21(4): 366 - 369. [Abstract] [PDF] |
||||
![]() |
N. Mrachacz-Kersting, M. Fong, B. A. Murphy, and T. Sinkjaer Changes in Excitability of the Cortical Projections to the Human Tibialis Anterior After Paired Associative Stimulation J Neurophysiol, March 1, 2007; 97(3): 1951 - 1958. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |