Characterizing the Cortical Activity through Which Pain Emerges from Nociception
| Autor: | Michael C. Lee, Gian Domenico Iannetti, André Mouraux |
|---|---|
| Přispěvatelé: | UCL - MD/FSIO - Département de physiologie et pharmacologie, University of Cambridge - Dept. of Anaesthesiology, UCL - SSS/IONS/COSY - Systems & cognitive Neuroscience |
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Adult
Male Pain Threshold Time Factors media_common.quotation_subject Electroencephalography - methods Pain Pain Threshold - physiology Stimulus (physiology) Brain mapping Pain - pathology physiopathology Young Adult Cerebral Cortex - pathology physiopathology Perception Evoked Potentials Somatosensory Afferent Pathways - physiopathology Humans media_common Pain Measurement Cerebral Cortex Evoked Potentials Somatosensory - physiology Afferent Pathways Analysis of Variance Brain Mapping General Neuroscience Interstimulus interval Lasers Electroencephalography Articles Nociception Anesthesia Nociceptor Female Analysis of variance Percept Psychology Pain Measurement - methods Neuroscience Lasers - adverse effects |
| Zdroj: | The Journal of Neuroscience, Vol. 29, no. 24, p. 7909-7916 (2009) The Journal of Neuroscience, Vol. 29, no. 24, p. 7909-16 (2009) |
| Popis: | Nociception begins when Adelta- and C-nociceptors are activated. However, the processing of nociceptive input by the cortex is required before pain can be consciously experienced from nociception. To characterize the cortical activity related to the emergence of this experience, we recorded, in humans, laser-evoked potentials elicited by physically identical nociceptive stimuli that were either perceived or unperceived. Infrared laser pulses, which selectively activate skin nociceptors, were delivered to the hand dorsum either as a pair of rapidly succeeding and spatially displaced stimuli (two-thirds of trials) or as a single stimulus (one-third of trials). After each trial, subjects reported whether one or two distinct painful pinprick sensations, associated with Adelta-nociceptor activation, had been perceived. The psychophysical feedback after each pair of stimuli was used to adjust the interstimulus interval (ISI) of the subsequent pair: when a single percept was reported, ISI was increased by 40 ms; when two distinct percepts were reported, ISI was decreased by 40 ms. This adaptive algorithm ensured that the probability of perceiving the second stimulus of the pair tended toward 0.5. We found that the magnitude of the early-latency N1 wave was similar between perceived and unperceived stimuli, whereas the magnitudes of the later N2 and P2 waves were reduced when stimuli were unperceived. These findings suggest that the N1 wave represents an early stage of sensory processing related to the ascending nociceptive input, whereas the N2 and P2 waves represent a later stage of processing related, directly or indirectly, to the perceptual outcome of this nociceptive input. |
| Databáze: | OpenAIRE |
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