Posterior grey column: I–VI Lamina I: marginal nucleus of spinal cord or posteromarginal nucleus[3] Lamina II: substantia gelatinosa of Rolando[3] Laminae III and IV: nucleus proprius[3] Lamina V: Neck of the dorsal horn. Neurons within lamina V are mainly involved in processing sensory afferent stimuli from cutaneous, muscle and joint mechanical nociceptors as well as visceral nociceptors. This layer is home to wide dynamic range tract neurons, interneurons and propriospinal neurons.