Well to answer this question, we have to go into simple Physiology of Nervous system and its sub-divisions.
CNS is composed of brain and SC, which harbors both somatic and autonomic parts of the nervous system (afferent and efferent).
Autonomic NS is automatic and consists of Para and sympathetic NS.
Both somatic and ANS also have peripheral parts, i.e. nerves to supply the end organs, albeit through separate fibers.
In the CNS the areas which control the skeletal muscles, specifically) are arranged in layers and work in hierarchy. The decision of doing a task is originated in the highest level of neurons, for example, walking. These highest level neurons are located in different areas of the brain and composed not only of the Somatic motor control area, but the autonomic and the cerebellar areas. Cerebellum is the part of the brain, which is continuously receiving and giving information about movement of any muscle, tendon, ligament, and joint hundreds of times a second. Programs for already mastered tasks, e.g. walking are all stored in cerebellum. When a program is launched, highest neurons give orders to higher level, then to middle level and then to alpha motor neurons (located in pons, midbrain, and spinal cord). When the movement starts, signals are repeatedly sent from those muscles, joints, tendons, and ligaments back, through thalamus, to these neurons as well as Cerebellum and basal ganglion. These latter two will check that the program being executed, i.e. walking, is going according to what is already mastered. If there is a mistake, they will send orders to correct it in milliseconds.
Hence, a simple thing like walking is a complex procedure starting in the CNS and not only impulses involved going towards the muscles are important, but the signals sent back to the brain from receptors play a major role.
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