Pain intensity, pain location and pain modulation: a combined neurophysiological and psychophysical approach. (360G-Wellcome-094863_Z_10_Z)

Pain is a complex subjective experience, most often caused by the activation of the nociceptive system. This project aims to investigate the neural bases of three cardinal aspects of pain perception: where it is (spatial localization), how much pain there is (intensity) and how it can be modulated by other somatosensory input (touch-pain interactions). Previous work on pain perception has been limited by poor control of pain stimuli and unreliable psychophysical techniques. We will resolve these problems by applying new fast, feedback-controlled laser stimulation, and improved subjective judgement methods, in a series of experiments with healthy volunteers. First, by investigating spatial acuity of pain, we will ask whether pain is more profoundly spatial than classically thought. By comparing its spatial precision to that of touch, we explore the possibility of shared spatial representations between the two senses. Second, we will develop improved pscyhophysical methods for reporting pain intensity, and then use these to better identify neural correlates of pain intensity using modern neuroimaging techniques. Finally, we combine this knowledge about spatial and intensity aspects of pain, to invest how nearby touch can inhibit pain. This basic understanding of pain mechanisms will have direct implications for clinical pain treatment.