NSCI 201 Chapter Notes - Chapter 16: Lower Motor Neuron, Alpha Motor Neuron, Anterior Grey Column

• School: McGill University
• Department: Neuroscience
• Course: NSCI 201
• Professor: Kevin Francis Casey

Document Summary

In this lecture: local circuit neurons in brainstem innervating motor neuron pools, where motor output is generated. Last stage in motor pathway, where all inputs are integrated to produce motion! Distribution of lower motor neurons in ventral horn of spinal cord! Motor neuron pool: all motor neurons innervating a single muscle! Colocalized to innervate from brain <> spinal cord, as well as rostro-caudally! Some segments span longer lengths of spinal cord than others! Medial portions corresponding to proximal parts of body, lateral parts innervating distal regions of body. (eg, muscles controlling trunk around midline)! Local circuit neurons in spinal cord gray matter ! More bilateral coordination needed here as one side contracts, the other needs to relax. Lateral circuits are ipsilateral, and span shorter distances. These control limb muscles; bilateral coordination is less important. Motor unit: all muscle bres innervated by a single alpha motor neuron. Related concept to motor pool; not to be confused.