The Nucleus proprius is a layer of the spinal cord adjacent to the substantia gelatinosa. Nucleus proprius constitutes the bulk of the dorsal horn and receives inputs from the dorsal root ganglions that carry sensory information, such as light touch, as well as pain and temperature information. Cells in this nucleus project to deeper laminae of the spinal cord, to the posterior column nuclei, and to other supraspinal relay centers including the midbrain, thalamus, and hypothalamus. Rexed laminae III, IV, and V make up the nucleus propius1 Nucleus proprius (NP), along with nucleus dorsalis (ND) are involved in sensing fine touch and proprioception.
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