Somatic Nervous System

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The somatic nervous system, part of the peripheral nervous system (PNS), controls voluntary movements like muscle contractions throughout the body. Nerves deliver information from the senses to the brain and carry commands from the brain to the muscles to allow movement. For internal organs, the somatic nervous system helps indicate organ pain using “referred pain” — feeling pain in a specific area while it’s coming from a problem nearby (pain from a heart attack felt in the left arm, back, jaw, or abdomen). It also controls when you inhale and exhale, either automatically or deliberately. Two responsibilities:

• Sensory input. All senses travel through the somatic nervous system to the brain except sight (retina/optic nerve connect directly to the brain). Touch sense below the neck travels the somatic nervous system to spinal cord, relays signals to brain.
• Movement control. Signals from the brain must pass through the somatic nervous system to reach the body’s muscles that give them instructions to facilitate movement. Somatosensation is vital for motor learning and motor recovery after brain damage