Fig. 4
From: Spinal cord stimulation in chronic pain: evidence and theory for mechanisms of action
Changes in Dorsal Horn Circuitry to chronic pain and SCS. In the development of chronic pain, neural circuitry undergoes rewiring wherein abnormal enhancement of excitatory pathways and loss of inhibition facilitate nociceptive transmission to sub-threshold stimuli. Increased excitatory interneuron input, decreased inhibitory interneuron input and local factors contribute to pathologic destabilization of normal input balance to the projection neuron. SCS changes the balance of nociceptive and antinociceptive inputs through the activation of local segmental and descending supraspinal mechanisms to in-part restore balance to this network. Acronyms: DCN (Dorsal Column Nuclei), E (Excitatory Interneuron), I (Inhibitory Interneuron), PN (Projection Neuron), SP (Substance P), Glu (Glutamate), GABA (Gamma Aminobutyric Acid), 5-HT (5-Hydroxytryptamine, Serotonin)