Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.15.205484v1?rss=1 Authors: Barik, A., Sathyamurthy, A., Thompson, J., Seltzer, M., Levine, A., Chesler, A. Abstract: Painful stimuli evoke a mixture of sensations, negative emotions and behaviors. These myriad effects are thought to be produced by parallel ascending circuits working in combination. Here we describe a pathway from spinal cord to brain for ongoing pain. Activation of a defined subset of spinal projection neurons expressing Tacr1 evokes a full repertoire of somatotopically-directed coping behaviors in the absence of noxious input. These cells project to a tiny cluster of Tacr1-positive neurons in the superior lateral parabrachial nucleus (PBN-SL) that themselves are responsive to sustained but not acute noxious stimuli. Activation of these PBN-SLTacr1 neurons alone does not trigger pain responses but instead serves to dramatically heighten nocifensive behaviors and suppress itch. Remarkably, mice with silenced PBN-SLTacr1 neurons ignore long-lasting noxious stimuli. These data reveal a spinoparabrachial pathway that plays a key role in the sensation of ongoing pain. Copy rights belong to original authors. Visit the link for more info