The dorsal column nuclei encode and transmit the network signatures of mechanical allodynia

The neural circuits that transmit the sense of pain and how pain is encoded by these circuits are still poorly understood.Mechanical allodynia is a prominent form of chronic pain characterized by painful responses to innocuous touch that develops as a consequence of nerve damage and inflammation. Here, we show that alterations to the normal log-normal distribution of neuronal activity and structure of neural correlations between neurons in the dorsal column nuclei (DCN) constitute a signature feature of mechanical allodynia, with the transmission of "allodynic" light touch information to the thalamus by somatostatin-positive projection neurons in the DCN being essential for its expression and development. Our findings are consistent with neural activity in the DCN encoding a reference landscape of tactile percepts that animals use to differentiate innocuous touch from potentially noxious mechanical stimuli.