title: The representation of social facial touch in rat barrel cortex.
abstract: Controlled presentation of stimuli to anesthetized [1] or awake [2] animals suggested that neurons in sensory cortices respond to elementary features [3, 4], but we know little about neuronal responses evoked by social interactions. Here we investigate processing in the barrel cortex of rats engaging in social facial touch [5, 6]. Sensory stimulation by conspecifics differs from classic whisker stimuli such as deflections, contact poles [7, 8], or textures [9, 10]. A large fraction of barrel cortex neurons responded to facial touch. Social touch responses peaked when animals aligned their faces and contacted each other by multiple whiskers with small, irregular whisker movements. Object touch was associated with larger, more regular whisker movements, and object responses were weaker than social responses. Whisker trimming abolished responses. During social touch, neurons in males increased their firing on average by 44%, while neurons in females increased their firing by only 19%. In females, socially evoked and ongoing firing rates were more than 1.5-fold higher in nonestrus than in estrus. Barrel cortex represented socially different contacts by distinct firing rates, and the variation of activity with sex and sexual status could contribute to the generation of gender-specific neural constructs of conspecifics.
authors.affiliation: Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Philippstrasse 13, Haus 6, 10115 Berlin, Germany; Berlin School of Mind and Brain, Humboldt University of Berlin, Unter den Linden 6, 10099 Berlin, Germany.
authors.forename: Evgeny
authors.initials: E
authors.lastname: Bobrov
authors.affiliation: Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Philippstrasse 13, Haus 6, 10115 Berlin, Germany.
authors.forename: Jason
authors.initials: J
authors.lastname: Wolfe
authors.affiliation: Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Philippstrasse 13, Haus 6, 10115 Berlin, Germany.
authors.forename: Rajnish P
authors.initials: RP
authors.lastname: Rao
authors.affiliation: Bernstein Center for Computational Neuroscience, Humboldt University of Berlin, Philippstrasse 13, Haus 6, 10115 Berlin, Germany. Electronic address: michael.brecht@bccn-berlin.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Brecht
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D008297:Male; D051381:Rats; D012737:Sex Factors; D012919:Social Behavior; D014110:Touch / Q000502:physiology*; D014738:Vibrissae / Q000502:physiology