NEUR30003 Lecture Notes - Lecture 11: Alpha Motor Neuron, Tendon Reflex, Extraocular Muscles

• School: University of Melbourne
• Department: Neuroscience
• Course: NEUR30003
• Professor: Peter

Document Summary

Lecture 12: the lower motornueron: motor(cid:374)euro(cid:374)s: the (cid:862)fi(cid:374)al (cid:272)o(cid:373)(cid:373)o(cid:374) pathwa(cid:455)(cid:863, the motor unit, connections to motorneurons: peripheral, segmental and supra-spinal, more complex spinal circuits: intersegmental coordination & pattern regeneration. Overall organization of neural structures that control movement. Output from ns is the effector (skeletal muscle) 30 thousand neurons in chicken, 100 thousand in humans. Bigger neuron, bigger peripheral targets e. g. muscles. Spatial distribution of lower motor neurons in the ventral horn of the spinal cord. Motor neurons sit in the anterior/posterior horn in clusters or constellations constellations are grouped approximately (slightly overlapping constellation depending on which muscle they are responsible for) Somatotopic organization of lower motor neurons results from retrograde labeling of muscles. Muscles that are proximal, close to the midline, have motor neurons that are also close to the midline medial in the spinal chord. Distal muscles have neurons that innervate them in a lateral location in the spinal chord.