Fig. 4: Primary afferent nociceptors transmit noxious stimuli via the dorsal root ganglion to projection neurons situated in the spinal cord’s dorsal horn.

A subgroup of these projection neurons transmits noxious stimuli to the thalamus which is then relayed to the somatosensory cortex. The somatosensory cortex is responsible for the location and quality of the noxious stimuli. The parabrachial nucleus and the amygdala transmit noxious stimuli to the ACC, basal ganglia (BG), insula, and PFC, which play a significant role in regulating the emotional and affective aspects of the pain experience. Figure was created with BioRender.com.