The effect of chain fibre ‘driving’ on the length sensitivity of primary sensory endings in the tenuissimus, peroneus tertius and soleus muscles
Direct observation of cat muscle spindles has shown that driving of primary endings (one afferent spike per γ efferent impulse constitutes 1:1 driving) by static γ axons is due to mechanical excitation of the small spirals of the primary sensory ending by oscillating nuclear chain fibres (Boyd et al., 1977). Driving has now been studied in 25 tenuissimus spindles and two from each of the peroneus tertius and soleus muscles to assess the generality of the phenomenon.
KeywordsSoleus Muscle Muscle Length Final Length Chain Fibre Rapid Muscle
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