All nerves involved in the voluntary control of skeletal muscles are part of the
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The somatic nervous system is the part of the peripheral nervous system and is associated with skeletal muscle voluntary control of body movements. The somatic nervous system is traditionally considered a division within the peripheral nervous system. However, this misses an important point: somatic refers to a functional division, whereas peripheral refers to an anatomic division. The somatic nervous system is responsible for our conscious perception of the environment and
for our voluntary responses to that perception by means of skeletal muscles. Peripheral sensory neurons receive input from environmental stimuli, but the neurons that produce motor responses originate in the central nervous system. Somatic nervous systemThe somatic nervous system is the part of the peripheral nervous system associated with the voluntary control of body movements through the action of skeletal muscles, and with reception of external stimuli, which helps keep the body in touch with its surroundings (e.g., touch, hearing, and sight). The system includes all the neurons connected with muscles, skin and sense organs. The somatic nervous system consists of afferent nerves that receive sensory information from external sources and transmit them to the brain and of efferent nerves responsible for receiving brain communications for muscle contraction. Additional recommended knowledgeContents
Nerve signal transmissionThe somatic nervous system processes sensory information and controls all voluntary muscular systems within the body, with the exception of reflex arcs. The basic route of nerve signals within the efferent somatic nervous system involves a sequence that begins in the upper cell bodies of motor neurons (upper motor neurons) within the precentral gyrus (which approximates the primary motor cortex). Stimuli from the precentral gyrus are transmitted from upper motor neurons and down the corticospinal tract, via axons to control skeletal (voluntary) muscles. These stimuli are conveyed from upper motor neurons through the ventral horn of the spinal cord, and across synapses to be received by the sensory receptors of alpha motor neuron (large lower motor neurons) of the brainstem and spinal cord. Upper motor neurons release a neurotransmitter, acetylcholine, from their axon terminal knobs, which are received by nicotinic receptors of the alpha motor neurons. In turn, alpha motor neurons relay the stimuli received down their axons via the ventral root of the spinal cord. These signals then proceed to the neuromuscular junctions of skeletal muscles. From there, acetylcholine is released from the axon terminal knobs of alpha motor neurons and received by postsynaptic receptors (Nicotinic acetylcholine receptors) of muscles, thereby relaying the stimulus to contract muscle fibers. Vertebrate and invertebrate differencesIn invertebrates, depending on the neurotransmitter released and the type of receptor it binds, the response in the muscle fiber could either be excitatory or inhibitory. For vertebrates, however, the response of a muscle fiber to a neurotransmitter (always acetylcholine (ACh)) can only be excitatory or, in other words, contractile. Reflex arcsA reflex arc is an automatic reaction that allows an organism to protect itself reflexively when an imminent danger is perceived. In response to certain stimuli, such as touching a hot surface, these reflexes are 'hard wired' through the spinal cord. A reflexive impulse travels up afferent nerves, through a spinal interneuron, and back down appropriate efferent nerves. See also
Is voluntary muscle control part of the central nervous system?The somatic nervous system (SNS), or voluntary nervous system is the part of the peripheral nervous system associated with the voluntary control of body movements via skeletal muscles.
What part of the nervous system is voluntary?The somatic nervous system (SNS) is also known as the voluntary nervous system.
What nerve controls skeletal muscle?The somatic nervous system, also called the somatomotor or somatic efferent nervous system, supplies motor impulses to the skeletal muscles. Because these nerves permit conscious control of the skeletal muscles, it is sometimes called the voluntary nervous system.
What system is used for skeletal muscle voluntary?The peripheral portion of the central nervous system (CNS) controls the skeletal muscles. Thus, these muscles are under conscious, or voluntary, control.
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