Bernstein Center for Computational Neuroscience Berlin, Institut für Biologie, Humboldt-Universität zu Berlin, Philippstraße 13, Haus 6, 10115 Berlin, Germany; Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany
Michael Brecht
Bernstein Center for Computational Neuroscience Berlin, Institut für Biologie, Humboldt-Universität zu Berlin, Philippstraße 13, Haus 6, 10115 Berlin, Germany; NeuroCure Cluster of Excellence, Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
Shimpei Ishiyama
Bernstein Center for Computational Neuroscience Berlin, Institut für Biologie, Humboldt-Universität zu Berlin, Philippstraße 13, Haus 6, 10115 Berlin, Germany; Institut für Pathophysiologie, Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Duesbergweg 6, 55128 Mainz, Germany; Corresponding author
Summary: The cellular mechanisms of emotional contagion are unknown. We investigated tickle contagion and the underlying neuronal representations in playful rats. We recorded trunk somatosensory cortex activity of observer rats while they received tickling and audiovisual playback of tickling footage and while they witnessed tickling of demonstrator rats. Observers vocalized and showed “Freudensprünge” (“joy jumps”) during witnessing live tickling, while they showed little behavioral responses to playbacks. Deep layers in the trunk somatosensory neurons showed a larger correlation between direct and witnessed tickling responses compared to superficial layers. Trunk somatosensory neurons discharged upon emission of own and demonstrator’s vocalizations and might drive contagious “laughter”. We conclude that trunk somatosensory cortex might represent ticklishness contagion.
