| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Physiology, University of Montreal, Montreal, Quebec, Canada
* To whom correspondence should be addressed. E-mail: trevor.drew{at}umontreal.ca.
We have used the technique of spatial facilitation to examine the interactions between the signals conveyed by the corticospinal tract and those of cutaneous afferents in the hindlimb of the intact, walking cat. Microstimulation was applied to 20 cortical sites in the hindlimb representation of the motor cortex and to 3 different cutaneous nerves innervating the hindpaw in 4 cats. Conditioning stimuli to the motor cortex induced both facilitation and depression of cutaneous reflexes evoked by stimulation of nerves in the hindlimb contralateral to the cortical stimulation site. Facilitation was most frequently evoked by conditioning stimuli in the range of 10 - 30 ms before the cutaneous stimulation; depression was normally evoked by shorter and longer conditioning delays. Similar changes were observed after conditioning stimuli to the pyramidal tract, suggesting that the changes were independent of any changes in cortical excitability. Modulation of reflex activity varied according to the muscle under study, the cutaneous nerve used to evoke the reflex and the cortical site used to condition the reflex. Together, these results suggest that there is spatial convergence of corticospinal and cutaneous afferent activity and that this convergence is mediated by distinct subpopulations of spinal interneurones.
This article has been cited by other articles:
|
|
 |
|
  A. Frigon, G. Barriere, H. Leblond, and S. Rossignol Asymmetric Changes in Cutaneous Reflexes After a Partial Spinal Lesion and Retention Following Spinalization During Locomotion in the Cat J Neurophysiol, November 1, 2009; 102(5): 2667 - 2680. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Frigon and S. Rossignol Locomotor and Reflex Adaptation After Partial Denervation of Ankle Extensors in Chronic Spinal Cats J Neurophysiol, September 1, 2008; 100(3): 1513 - 1522. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Frigon and S. Rossignol Adaptive changes of the locomotor pattern and cutaneous reflexes during locomotion studied in the same cats before and after spinalization J. Physiol., June 15, 2008; 586(12): 2927 - 2945. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Haridas, E. P. Zehr, and J. E. Misiaszek Adaptation of Cutaneous Stumble Correction When Tripping Is Part of the Locomotor Environment J Neurophysiol, June 1, 2008; 99(6): 2789 - 2797. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y.-C. Pai and T. S Bhatt Repeated-Slip Training: An Emerging Paradigm for Prevention of Slip-Related Falls Among Older Adults Physical Therapy, November 1, 2007; 87(11): 1478 - 1491. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. A. McVea and K. G. Pearson Long-Lasting, Context-Dependent Modification of Stepping in the Cat After Repeated Stumbling-Corrective Responses J Neurophysiol, January 1, 2007; 97(1): 659 - 669. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Bretzner and T. Drew Changes in Corticospinal Efficacy Contribute to the Locomotor Plasticity Observed After Unilateral Cutaneous Denervation of the Hindpaw in the Cat J Neurophysiol, October 1, 2005; 94(4): 2911 - 2927. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
