Neural response to bird's own song and tutor song in the zebra finch field L and caudal mesopallium

Neurons in the song system nuclei of songbirds exhibit a strong preference for the sound of the bird's own song relative to that of conspecific songs. This selectivity is observed in the high vocal center and the nucleus interface of the nidopallium, two song nuclei that receive input from the bird's auditory system. To investigate the role of the auditory system in generating the selective responses observed in the song system, we recorded auditory responses in the zebra finch primary auditory forebrain, field L, and in a secondary auditory area, the caudal mesopallium. Field L and caudal mesopallium project directly or indirectly to the high vocal center and nucleus interface of the nidopallium and are presumed to provide substantial auditory input to the song system. We found that, on average, neurons in field L and caudal mesopallium did not show positive selective responses for the bird's own song or tutor song relative to conspecific song. Moreover, there were no particular sub-areas in the auditory telencephalon that were relatively more selective than the average. The selectivity for the bird's own song would therefore be restricted to song nuclei and would arise in one processing step, potentially found at the interface between the auditory and the song systems