Functional neuroanatomy of the spinal cord

Abstract

The spinal cord (SC) is the part of the central nervous system (CNS) that is responsible for the motor, somato-sensory, and visceral innervation of the extremities, trunk, and large parts of the neck as well as all inner organs. Spinal nerves of the peripheral nervous system (PNS) serve as connections between the CNS and distal receptors and organs. And just as the SC controls many aspects of locomotion and visceral function, it also serves as an important relay station for incoming, afferent information from the periphery to central brain regions. It thus constitutes the major coordination hub for how humans unconsciously perceive their periphery and how our bodies react to this information, often involuntarily and without involvement of higher brain functions. And while the topography and cytoarchitecture of the human spinal cord is fairly well understood, the functional implications of some well-described structures remain elusive. Because of the central role the spinal cord plays in many forms of CNS impairment, a better understanding of the functional neuroanatomy of this structure is a prerequisite for addressing potential therapeutic approaches. This chapter gives an overview of spinal cord development, topography, cytoarchitecture, and functional assembly with a special focus on two aspects often compromised during spinal cord injury, namely, the control of micturition and the propriospi- nal neuron networks that hold great promise for the future improvement of therapies for patients suffering from spinal cord injury.