Overview / α and γ rigidity
α and γ rigidity
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increased muscle tone can have two forms:
- ALPHA RIGIDITY: results from an increase in excitatory signals or decrease in inhibitory signals that contact alpha motorneurons directly, resulting in contraction of extrafusal fibres, and generation of force
- independent of stretch reflex pathways
- GAMMA RIGIDITY: results from an increase in excitatory signals or decrease in inhibitory signals that contact gamma motorneurons that result in contraction of intrafusal fibres
- dependent upon stretch reflex pathways
- ALPHA RIGIDITY: results from an increase in excitatory signals or decrease in inhibitory signals that contact alpha motorneurons directly, resulting in contraction of extrafusal fibres, and generation of force