Test Yourself What are the three inputs to an alpha motor neuron? What is the organization of the spinal column with regard to flexation, extension, axial and distal muscle control? . What is the molecular mechanism behind a muscle contraction? . What muscles do alpha motor neurons innervate? What is the functional role of these neurons? What about Gamma motor neurons? . What does a muscle spindle sense? Golgi tendon organ? What is the consequence of activating each of these sensory pathways? Do you understand spinal interneurons? Inhibitory, excitatory? What is the complete circuit regulating the strecth reflex?