Rodriguez-Saltos, C. A. | bioRxiv Science

bioRxiv2021

Oxytocin receptor antagonism during song tutoring in zebra finches reduces preference for and learning of the tutor's song

In species with vocal learning, acquiring species-typical vocalizations relies on early social orienting. In zebra finches (Taeniopygia guttata), for example, learning song requires dynamic social interactions with a "tutor" during an early sensitive period. The oxytocin system plays a central role in social orienting across species, yet it is unknown whether this system participates in the attentional and motivational processes that support vocal learning. Here, we tested whether blocking oxytocin receptors during exposure to tutors would impact learning from those tutors. Juvenile, song-naive males were each tutored by two unfamiliar adults. During exposure to one tutor, juveniles were treated with oxytocin receptor antagonist (OTA) and during exposure to the other, saline (control). We found that OTA significantly reduced behaviors associated with approach and attention during tutoring sessions. Next, using an operant assay in which exposure to the two songs was balanced, we found that the juveniles preferred the control song over the OTA song. The developmental trajectory of preference for the control song resembled the pattern shown by father-reared birds choosing to hear their fathers song. Finally, the adult songs of the tutored birds more closely resembled control song than OTA song. The magnitude of this difference was significantly predicted by the early preference for the control song. Overall, oxytocin antagonism during exposure to a tutor seemed to bias juveniles against that tutor and his song. Our results suggest that oxytocin receptors play a role in socially-guided vocal learning in zebra finches, perhaps by affecting attention and motivation during tutoring.

animal behavior and cognition↗

bioRxiv2021

Song preferences predict the quality of vocal learning in zebra finches

In songbirds, learning to sing is a highly social process that likely involves social reward. Here, we hypothesized that the degree to which a juvenile songbird learns a song depends on the degree to which it finds that song rewarding to hear during vocal development. We tested this hypothesis by measuring song preferences in young birds during song learning and then analyzing their adult songs. Song preferences were measured in an operant key-pressing assay. Juvenile male zebra finches (Taeniopygia guttata) had access to two keys, each of which was associated with a higher likelihood of playing the song of their father or that of another familiar adult ("neighbor"). To minimize the effects of exposure on learning, we implemented a reinforcement schedule that allowed us to detect preferences while balancing exposure to each song. On average, the juveniles significantly preferred the fathers song early during song learning, before they were themselves singing. At around post-hatch day 60, their preference shifted to the neighbors song. At the end of the song learning period, we recorded the juveniles songs and compared them to the fathers and the neighbors song. All of the birds copied fathers song. The accuracy with which the fathers song was imitated was positively correlated with the peak strength of the preference for the fathers song during the sensitive period. Our results show that preference for a social stimulus, in this case a vocalization, predicted social learning during development.

animal behavior and cognition↗