The recruitment order of stapedius motoneurons in the acoustic reflex varies with sound laterality.
In many muscles, motor units are recruited in a fixed order with increasing strength of muscular contraction. We show that for the stapedius muscle of the cat, vastly different recruitment orders can be obtained, depending on which ear is acoustically stimulated. The data support the idea that the distribution of inputs to a motoneuron pool can be inhomogeneous and a significant factor in determining recruitment order.
Eaton-Peabody Laboratory of Auditory Physiology, Massachusetts Eye and Ear Infirmary, Boston 02114.
J B
JB
Kobler
S R
SR
Vacher
J J
JJ
Guinan
D000818:Animals; D001307:Auditory Perception / Q000502:physiology*; D002415:Cats; D009046:Motor Neurons / Q000502:physiology*; D009132:Muscles / Q000294:innervation*; D009431:Neural Conduction; D011999:Recruitment, Neurophysiological; D012022:Reflex, Acoustic; D012684:Sensory Thresholds; D013017:Sound Localization / Q000502:physiology*; D013198:Stapedius / Q000294:innervation*