ISSN:
1432-1106
Keywords:
Polysynaptic Ia excitation
;
Spinal interneurones
;
Voluntary movement
;
Human quadriceps
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Homonymous Ia facilitation of quadriceps (Q) motoneurones (MNs) was significantly larger during (and at the onset of) a very weak Q voluntary contraction than at rest. This increase in Ia facilitation only appeared with a conditioning-test interval within the narrow range of 5–9 ms, which fits the time course of the recently described polysynaptic Ia excitation to Q MNs. This suggests that interneurones mediating polysynaptic Ia excitatory effects to Q MNs receive a strong descending excitation during such a contraction. It is therefore argued that these interneurones might mediate part of the descending command to Q MNs during voluntary contraction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00236863
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