TY - JOUR T1 - Nociceptive-evoked potentials are sensitive to behaviourally relevant stimulus displacements in egocentric coordinates JF - eneuro JO - eneuro DO - 10.1523/ENEURO.0151-15.2016 SP - ENEURO.0151-15.2016 AU - M. Moayedi AU - G. Di Stefano AU - M. T. Stubbs AU - B. Djeugam AU - M. Liang AU - G. D. Iannetti Y1 - 2016/06/13 UR - http://www.eneuro.org/content/early/2016/06/10/ENEURO.0151-15.2016.abstract N2 - Feature selection has been extensively studied in the context of goal-directed behaviour, where it is heavily driven by top-down factors. A more primitive version of this function is the detection of bottom-up changes in stimulus features in the environment. Indeed, the nervous system is tuned to detect fast-rising, intense stimuli that are likely to reflect threats, such as nociceptive somatosensory stimuli. These stimuli elicit large brain potentials maximal at the scalp vertex. When elicited by nociceptive-specific laser stimuli, these responses are labeled laser-evoked potentials (LEPs). While it has been shown that changes in stimulus modality and increases in stimulus intensity evoke large LEPs, it has yet to be determined whether stimulus displacements affect the amplitude of the main LEP waves (N1, N2 and P2). Here, in three experiments, we identified a set of rules that the human nervous system obeys to identify changes in the spatial location of a nociceptive stimulus. We showed that the N2 wave is sensitive to (1) large displacements between consecutive stimuli in egocentric, but not somatotopic coordinates, and (2) displacements that entail a behaviourally relevant change in the stimulus location. These findings indicate that nociceptive-evoked vertex potentials are sensitive to behaviourally relevant changes in the location of a nociceptive stimulus with respect to the body, and that the hand is a particularly behaviourally important site.Significance Statement: The ability to detect behaviourally-relevant events when navigating in an ever-changing sensory environment is important for survival. What are the rules that the nervous system obeys to identify which changes in stimulus location are important to attend?Here, we show that changes in the spatial location of a nociceptive stimulus elicit an enhanced brain potential at the scalp vertex (vertex potential) only when they represent a threat to the body. These findings show that the magnitude of the vertex potential, relies not only on low-level stimulus features, but also complex information such as the stimulus location with respect to the body. Our results support the role of the nociceptive-evoked vertex potential in threat detection in an ever-changing sensory environment. ER -