The cell bodies of somatic motor neurons, also known as motor neurons, are located in the central nervous system (CNS) of the human body. Specifically, they are found in the spinal cord and brainstem.In the spinal cord, motor neuron cell bodies are located in the anterior horn of the gray matter. The anterior horn is the ventral (front) part of the spinal cord and is responsible for the initiation and control of voluntary movement. The motor neurons in the spinal cord send their axons out of the cord and into the peripheral nervous system (PNS) to innervate skeletal muscles. These motor neurons are responsible for controlling muscle tone, posture, and movement.In the brainstem, motor neuron cell bodies are located in the ventral horn of the gray matter, specifically in the medulla oblongata, pons and midbrain. The brainstem is responsible for controlling essential functions such as breathing, heart rate, and blood pressure, and it also contains a number of nuclei that are important for the control of movement.It's important to note that motor neurons are a subtype of the larger class of neurons called efferent neurons, which are responsible for transmitting signals from the CNS to the PNS, such as muscles and glands. The opposite of efferent neurons are afferent neurons, which transmit signals from the PNS to the CNS.In summary, the cell bodies of somatic motor neurons are located in the spinal cord and brainstem in the ventral horn of the gray matter, specifically in the anterior horn of the spinal cord and in the ventral horn of the brainstem in the medulla oblongata, pons, and midbrain. These neurons are responsible for controlling skeletal muscle movement and also play a role in essential functions such as breathing, heart rate and blood pressure.