Fig. 3.

Eight of fifteen birds showed degraded song after treatment to cause hair cell loss. Syllable sequences returned to the original, pretreatment order, and some aspects of syllable structure recovered toward that of the original song by 4 weeks after treatment. A, Spectrograph (frequency over time plot) of two song motifs recorded before treatment.B, Spectrograph of a syllable sequence from the same bird as in A but recorded 1 d after the end of treatment. Comparison of A and B shows that syllable order and the acoustic structure of syllables degraded in this bird after treatment. C, Two song motifs from the same bird as in A and B recorded 4 weeks after treatment. Comparison of the three panels shows that the song recorded after 4 weeks of recovery appears similar to the pretreatment song and dissimilar to the song recorded immediately after treatment. Individual syllables are labeled withnumbers, and notes are labeled withletters below the x-axis.Darkness indicates the intensity of vocalizations.