title: Self-touch modulates the somatosensory evoked P100.
abstract: It has recently been shown that contact between one's own limbs (self-touch) reduces the perceived intensity of pain, over and above the well-known modulation of pain by simultaneous colocalized tactile input Kammers et al. (Curr Biol 20:1819-1822, 2010). Here, we investigate how self-touch modulates somatosensory evoked potentials (SEPs) evoked by afferent somatosensory input. We show that the P100 SEP component, which has previously been implicated in the conscious perception of a tactile stimulus, is enhanced during self-touch, as compared to when one is touching nothing, an inanimate object, or another person. A follow-up experiment showed that there was no effect of self-touch on SEPs when the body parts in contact were not symmetric. Altogether, our findings suggest the interpretation that the secondary somatosensory cortex might underlie the specific analgesic effect of self-touch.
authors.affiliation: Experimental Psychology Division, Helmholtz Institute, Universiteit Utrecht, Utrecht, The Netherlands. j.h.a.hogendoorn@uu.nl.
authors.forename: Hinze
authors.initials: H
authors.lastname: Hogendoorn
authors.affiliation: Experimental Psychology Division, Helmholtz Institute, Universiteit Utrecht, Utrecht, The Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: Kammers
authors.affiliation: Institute of Cognitive Neuroscience, University College London, London, UK.
authors.forename: Patrick
authors.initials: P
authors.lastname: Haggard
authors.affiliation: Experimental Psychology Division, Helmholtz Institute, Universiteit Utrecht, Utrecht, The Netherlands.|Department of Psychology, University of Sydney, Sydney, Australia.
authors.forename: Frans
authors.initials: F
authors.lastname: Verstraten
mesh_terms: D000328:Adult; D000698:Analgesia; D004569:Electroencephalography / Q000379:methods*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D006801:Humans; D059225:Nociception / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*
keywords: Analgesia; Nociception; SEPs; Self-touch; Somatosensory evoked potentials