Single-unit recordings from monkey spinothalamic tract (STT) neurons reveal that the responses of polymodal nociceptive lamina I STT neurons correspond with the profile of burning pain elicited in human subjects by repeated brief-contact heat. In contrast, lamina V wide-dynamic-range (WDR) neurons show a significantly different response pattern. This finding indicates that burning pain is signaled by modality-selective lamina I neurons and not convergent lamina V WDR neurons.