that the effect of Type III Nrg1 signaling on TRPV1 in sensory neurons is important for thermal pain sensation and the development of thermal hypersensitivity in vivo. Our finding that Type III Nrg1 signaling in sensory neurons regulates functional levels of the receptor TRPV1 in a way that may affect thermal pain sensation and inflammatory thermal hypersensitivity also has implications for understanding the neurobiology of sensory abnormalities occurring in schizophrenia. Schizophrenia patients show abnormalities in pain sensitivity [12,14,16,18,35], but these deficits were often attributed to general cognitive deficits seen in the disease. We now provide evidence that Type III Nrg1—a protein whose levels were decreased in tissue from some schizophrenia patients—is important for the perception of thermal pain, and that this behavioral effect may result from regulation of functional axonal TRPV1 by Type III Nrg1 signaling in nociceptive sensory neurons. 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Gen Hosp Psychiatry 12: 319–322. PLoS ONE | www.plosone.org 16 September 2011 | Volume 6 | Issue 9 | e25108