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The spinal cord helps relay sensory and motor information between the brain and the PNS.
The sensory receptors in the skin detect somatic sensory stimuli, such as touch, temperature, or pain, and transmit nerve impulses that travel through the sensory neurons to the spinal cord.
The impulse first reaches the dorsal root of the spinal cord and then travels to the dorsal gray horn.
An impulse may directly enter the white matter and ascend to the brain.
Alternatively, it can enter the interneurons of the dorsal gray horn. The axons of these interneurons enter the white matter to reach the brain.
The impulse entered in the dorsal gray horn may take the third path, reaching the somatic motor neurons involved in spinal reflex pathways.
Similarly, the motor output from the brain first descends into the white matter of the spinal cord. Then, it enters the ventral gray horn and ventral root to reach the spinal nerve.
The impulse is finally carried to the target muscles for the intended response.
The spinal cord is an integral hub for motor and sensory information that enables the brain to communicate with the peripheral nervous system (PNS). T…
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