Precise auditory–vocal mirroring in neurons for learned vocal communication Nature 451, 305-310 (17 January 2008) doi:10.1038/nature06492 http://www.nature.com/nature/journal/v451/n7176/full/nature06492.html J. F. Prather, S. Peters, S. Nowicki & R. Mooney Brain mechanisms for communication must establish a correspondence between sensory and motor codes used to represent the signal. One idea is that this correspondence is established at the level of single neurons that are active when the individual performs a particular gesture or observes a similar gesture performed by another individual. Although neurons that display a precise auditory–vocal correspondence could facilitate vocal communication, they have yet to be identified. Here we report that a certain class of neurons in the swamp sparrow forebrain displays a precise auditory–vocal correspondence. We show that these neurons respond in a temporally precise fashion to auditory presentation of certain note sequences in this songbird's repertoire and to similar note sequences in other birds' songs. These neurons display nearly identical patterns of activity when the bird sings the same sequence, and disrupting auditory feedback does not alter this singing-related activity, indicating it is motor in nature. Furthermore, these neurons innervate striatal structures important for song learning, raising the possibility that singing-related activity in these cells is compared to auditory feedback to guide vocal learning.
See also: Editor's summary http://www.nature.com/nature/journal/v451/n7176/edsumm/e080117-07.html Listen and learn The 'mirror' neurons found in primates allow an individual to mimic or mirror another's behaviour, as they fire when a specific action, such as a hand gesture, is either performed or observed. A prime example of mimicry is vocal learning, as in human speech and birdsong. An obvious job for mirror neurons perhaps, but until now no auditory-vocal mirror neurons had been reported. Now, in a study of the swamp sparrow, a bird that resembles humans in its dependence on auditory experience to learn its vocal repertoire, a class of forebrain neurons specialized for auditory-vocal monitoring has been identified. They have virtually the same response to a given note sequence, whether performed or heard. News and Views Behavioural neuroscience: Neurons of imitation p249 http://www.nature.com/nature/journal/v451/n7176/full/451249a.html Ofer Tchernichovski & Josh Wallman In songbirds, a class of neurons shows a striking similarity in activity when the bird sings and when it hears a similar song. This mirroring neuronal activity could contribute to imitation. Enjoy! Xiao XIAO, Jianqiang, Ph.D. Research Associate Psychology Department Rutgers University 152 Frelinghuysen Road Piscataway, NJ 08854
