HVC is an area of the birdsong production system that has properties that are similar to the “mirror-neurons” seen in primates, including people. HVC neurons activate when a bird sings its song, but they will also activate when the same bird is passively listening to birdsong. What controls the strength of HVC’s response to birdsong? At Sensorimotor Journal Club on Tuesday, December 19th, Kris Bouchard will talk about some work that he and Michael Brainard have done looking at the effect of song context on HVC response to birdsong:
Neural Encoding of Song Statistics In Sensorimotor Nucleus HVC of Bengallese Finch
The natural statistics of the environment can have dramatic effects on the development and activity of networks of neurons in many sensory areas. Here we report that the population of neurons in sensory/motor nucleus HVC of songbirds encodes the transition probabilities found in the produced song, the most salient acoustic event in its environment. By playing back long strings of randomly sequenced syllables, we probed the effect of syllabic context on the population response to a given syllable and report that, within the family of naturally produced sequences, the most probable non-repeated transitions elicited strongest responses and had positive integrations extending up to 5 syllables. These data are consistent with an emerging picture of HVC selectivity that responses to auditory stimuli are strongly shaped by bird's experience of his own song and further supports the hypothesis that HVC is a major site of sensorimotor integration in the song system. In contrast, repeated transitions resulted in a decline in the auditory response with increased repeat number, suggesting that auditory feedback may be involved with the termination of repeat production during singing through stimulus-specific adaptation.
Kris’s results have some interesting parallels with a paper previously presented at Sensorimotor Journal Club on November 28th. In it, Schutz-Bosbach et al. explain their results (a reduced mirror-neuron response to seening the moving hand when the subject thinks the hand is his own) by suggesting it could be caused by an inhibitory response to seeing your own movements:
“Brass et al.  have reported an anterior frontomedial and right temporoparietal inhibitory network that suppresses a natural tendency to imitate others and thus prevents inappropriate responses. This would be even more important for preventing inappropriate perseveration or entrainment when viewing one’s own actions”
Come to Sensorimotor Journal Club on Tuesday, December 19th, listen to Kris’s talk, and we’ll discuss these issues!