HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Meunier, S Articles by Rossi, A Search for Related Content PubMed PubMed Citation Articles by Meunier, S Articles by Rossi, A

Hôpital de la Salpêtrière, Paris, France.

1. Ia projections and recurrent inhibition from quadriceps to tibialis anterior and soleus motoneurones were investigated in man. 2. Changes in the firing probability of individual voluntarily activated motor units were studied following electrical stimulation of the femoral nerve or quadriceps tendon tap. 3. Femoral nerve stimulation evoked an early increase in the firing probability of tibialis anterior units. This excitation was also evoked by a tendon tap, had a low threshold and its central delay was estimated to be the same as that of the homonymous monosynaptic Ia excitation. These findings strongly suggest that the femoral nerve-induced excitation is Ia in origin and mediated through a monosynaptic pathway. 4. The frequency of heteronymous Ia excitation from quadriceps was about the same to both ankle flexor and extensor units (79 and 70% respectively). 5. In 80% of both tibialis anterior and soleus units the Ia excitation was followed by a decrease in firing probability. This inhibition had a short latency and a long duration (up to 40 ms); it always appeared with the quadriceps reflex discharge and increased with it. These findings suggest that this decrease in firing probability is due to the Renshaw inhibition evoked by the quadriceps motoneurone discharge. 6. Both the Ia excitation and the following inhibition of tibialis anterior and soleus units were also observed when the stimulation was applied to the nerve of the vastus lateralis (a pure knee extensor). 7. The functional significance of these identical projections from quadriceps to both ankle flexor and extensor motoneurones is discussed with regard to the requirements of bipedal stance and gait.

This article has been cited by other articles:

				G. Courtine, S. J. Harkema, C. J. Dy, Y. P. Gerasimenko, and P. Dyhre-Poulsen Modulation of multisegmental monosynaptic responses in a variety of leg muscles during walking and running in humans J. Physiol., August 1, 2007; 582(3): 1125 - 1139. [Abstract] [Full Text] [PDF]

				R. J. H. Wilmink and T. R. Nichols Distribution of Heterogenic Reflexes Among the Quadriceps and Triceps Surae Muscles of the Cat Hind Limb J Neurophysiol, October 1, 2003; 90(4): 2310 - 2324. [Abstract] [Full Text] [PDF]

				J. F. Iles and J. Pardoe Changes in transmission in the pathway of heteronymous spinal recurrent inhibition from soleus to quadriceps motor neurons during movement in man Brain, September 1, 1999; 122(9): 1757 - 1764. [Abstract] [Full Text] [PDF]

				V. V. Turkin, K. S. Monroe, and T. M. Hamm Organization of Recurrent Inhibition and Facilitation in Motor Nuclei Innervating Ankle Muscles of the Cat J Neurophysiol, February 1, 1998; 79(2): 778 - 790. [Abstract] [Full Text] [PDF]