Retrograde labeling of neurons in spinal cord that project directly to nucleus accumbens or the septal nuclei in the rat

Somatosensory information has been thought to ascend from the spinal cord to limbic areas of the telencephalon through indirect, multisynaptic pathways. We now report that injections of Fluoro-gold into either the nucleus accumbens or the septal nuclei labeled hundreds of neurons in the spinal cord. These and our recent anterograde tracing experiments indicate that some spinal cord neurons project directly to the telencephalon and suggest that nucleus accumbens and septal nuclei process somatosensory information.