Bird song clue to human brain functions?

How birds learn songs and which brain circuits are used may have implications for diagnosing and treating human developmental disorders, U.S. scientists report. Researchers at Duke University say they found the same circuitry in a bird's brain involved in vocal control also participates in auditory learning, raising the possibility vocal circuits in the human brain also help encode auditory experience important to speech and language learning. "Birds learn their songs early in life by listening to and memorizing the song of their parent or other adult bird tutor, in a process similar to how humans learn to speak," Duke postdoctoral researcher Todd Roberts said. "They shape their vocalizations to match or copy the tutor's song." A young male zebra finch, Roberts said, learns his song in two phases -- memorization and practice. Memorization can be quick but the bird may need to practice singing as many as 100,000 times in a 45-day period to accurately imitate the tutor's song. "We learn some of our most interesting behaviors, including language, speech and music, by listening to an appropriate model and then emulating this model through intensive practice," senior author Richard Mooney, a professor of neurobiology, said in a Duke release. "A traditional view is that this two-step sequence -- listening followed by motor rehearsal -- first involves activation by the model of brain regions important to auditory processing. This is followed days, weeks or even months later by activation of brain regions important to motor control." The research has implications for the role of premotor circuits in the brain and suggests these areas are important targets to consider when assessing developmental disorders that affect speech, language and other imitative behaviors in humans, the researchers said.