Difference in selectivity to song note properties between the vocal nuclei of the zebra finch

Responses to a single note from a zebra finch song and an artificially modified note were recorded from neurons in the vocal nuclei in the zebra finch. Response patterns recorded in the higher vocal center (HVC) and the lateral magnocellular nucleus of the neostriatum (IMAN) were compared. A subset of neurons were found to preferentially respond to the original temporal sequence of the components of the note and/or the specific harmonic structure of the note. These neurons were more common in the IMAN than in the HVC. These results suggest that response selectivity to both the harmonic and temporal pattern of the note increases as auditory information flows from the HVC to the IMAN.