Bengalese Finches Lonchura Striata Domestica Depend upon Auditory Feedback for the Maintenance of Adult Song

摘要

Male birds of age-limited song-learning species develop their full song repertoires in the first year of life. For this type of song learner, once song is stabilized in adulthood, it is highly stereotyped and stable over time. Traditionally, it has been believed that age-limited song learners do not depend on auditory feedback for the maintenance of adult song. A recent report, however, showed that adult song in zebra finches, age-limited learners, does change after long-term deafness. We report here that another species of age-limited learner, Bengalese finches, depends critically on auditory feedback for adult song maintenance. We surgically deafened adult males and recorded song for 12 weeks after surgery. Results show that song degraded significantly within 1 week of surgery and continued to degrade over the next 11 weeks. This represents a more rapid degradation of song than has been seen previously in age-limited species. Song deficits after deafening included a marked decrease in syllable sequence stereotypy, skewed syllable distribution within song bouts, degradation of syllable phonology, and dropped, combined, and new or unrecognizable syllables. Decreased sequence stereotypy and combined syllables appeared within 1 week of deafening and did not worsen over time. Skewed syllable distributions and syllable phonology changes appeared after 1 week and did worsen. Occurrences of dropped and new syllables appeared within 1 week and increased over time. Comparison with other species indicates that much variability exists among species in the extent to which auditory feedback is necessary for song maintenance.