Vocal learning in songbirds is one example of a complex behavior which is learned. Like human speech learning, it is learned by first listening to a model song and then shaping vocalizations to match that model song. Also, like speech, song is dependant upon sensory feedback. This is an example of song from one of the tutors in our colony. We record song digitally and represent it in a spectrogram which is basically a frequency vs. time plot. Song is composed of individual syllables of varying complexity, put together into a sequence which we call a motif. A song bout is generally one to three different motifs repeated a number of times.
Behavioral variability in an adult songbird, the Bengalese finch. Cara Hampton, Michael Brainard UCSF
Vocal learning in songbirds is like speech learning in humans Bengalese Finch 30 d 60 d 90 d Sensory Sensorimotor Adult Song Tutor
Song is a learned motor skill it starts out extremely variable but then becomes finely tuned
What happens once a motor skill is well-learned? How is the brain involved? “ practice” = behavioral variability for the purpose of maintenance practice: fine tune and adjust behavior Practice and Performance performance: best version
My thesis work: Behavioral variability and the brain How is behavioral variability regulated by the brain? Why is behavioral variability regulated by the brain? Does behavioral variability exist in the adult Bengalese finch?
A male sings more variable song when alone than with a female more variable less variable
This variability is actively driven by a circuit in the brain:the AFP
Conclusions <ul><li>Adult behavior retains variability </li></ul><ul><li>song is more variable during “practice” </li></ul><ul><li>HOW? This behavioral variability is actively driven by the brain </li></ul><ul><li>AFP lesions remove variability during “practice” </li></ul><ul><li>WHY? This process may be important for behavioral maintenance. </li></ul><ul><li>AFP lesions also prevent recovery from injury. </li></ul>