Rodent models of pain such as nerve injury models are important to understand the mechanisms that may contribute to human neuropathic pain. Imaging studies in human have identified cortical regions specifically involved in the subjective, conscious perception of pain. Although laboratory animals process painful stimuli using similar mechanisms and thresholds of awareness as humans, it is much harder to assess the subjective pain experienced by animals as they can not self-report. This has led researchers to rely on objective measures of pain-related behaviors such as evoked responses to noxious stimuli. Humans, however, are able to voice discomfort, which provides rapid and direct access to the subjective experience.