![]() Songbirds can age out of the capacity to learn a tutor song just like a person can age out of the capacity to learn to speak French fluently." "That’s directly analogous to sensitive periods for human speech learning. "If the bird gets beyond a certain age, then it becomes very hard for it to learn from other birds," said Mooney. Notably, these simple songs are much less attractive to females, putting the unschooled bird at a serious disadvantage for mating. If juveniles don't meet a suitable tutor before they are 60 days old, they grow up to sing songs that are much simpler than those they might learn from a tutor. Scientists have known for decades that zebra finches have a sensitive period for song learning. ![]() In fact, turning off the PAG in juveniles caused them to ignore their tutors, suggesting that this brain area affects the young finch’s ability to recognize and attend to an appropriate tutor. The activity in the juvenile’s PAG continued for a short while even after the tutor stopped singing, meaning that the neurons likely respond to something other than sound - possibly social cues from the older bird. In young birds who hadn't met a tutor before, the researchers found that PAG neurons lit up with activity in the presence of a singing adult male, but were silent when the juvenile encountered quiet males or adult females, which do not sing, or heard zebra finch songs played over a speaker. In the finch, these dopamine-secreting PAG neurons send long fibers that end in the song cortex. The second is a pinhead-sized region known as the periaqueductal grey or PAG, which contains a group of nerve cells that release dopamine and, in mice, respond to other mice. The first is the part of the cortex essential for singing and is a bit like Broca's area in the human brain, which is essential to speech. The researchers focused their work on two areas of the finch’s brain. “Birdsong is one of the very few examples in the animal world where a behavior is transmitted from one generation to the next by imitation as opposed to genetic inheritance." The fact that birds learn “speech” as we do gives researchers the opportunity to use the animals to study how a young learner memorizes someone else's actions and then eventually learns to imitate those actions. "In humans it’s clear that being able to learn species-specific behaviors like speech is really important," said Richard Mooney, the George Barth Geller professor of neurobiology. If those connections aren’t activated, a young finch fails to copy the tutor’s song. 17 in the journal Nature, reveals that being near a singing tutor activates connections between a social area of the young bird's brain and the part of the brain responsible for the juvenile's ability to sing. ![]() The study, which appears early online Oct. Now, findings from Duke University scientists show how the juvenile birds identify the right teacher. Researchers already knew that juveniles don't copy songs played through a loudspeaker or sung by other species of birds. Young male zebra finches must learn to copy the song of an adult tutor in order to ultimately attract a mate. But young learners are selective in who they copy, and scientists don't understand how they choose the right teacher. These behavioral changes suggested the vocal control mechanisms on which the auditory feedback is based have a predictable effect on amplitude, but complex spectral effects on individual note production.Youngsters learn many important behaviors by imitating adults. Further, individually specific modes of changes in F0 are shown. The results confirmed that the Lombard effect occurs at the note level of Bengalese finch song. To accurately analyze these acoustic characteristics, two different bandpass-filtered noises at two levels of sound intensity were used. Here, the changes in amplitude and F0 with a focus on the distinct song elements (i.e., notes) of Bengalese finches under noise presentation are demonstrated. domestica) are a suitable model for comparative, ethological, and neuroscientific studies on audio-vocal interaction because they require real-time auditory feedback of their own songs to maintain normal singing. Bengalese finches ( Lonchura striata var. Along with vocal amplitude, other acoustic characteristics, including fundamental frequency (F0), also change in some species. One such audio-vocal interaction is the Lombard effect, an involuntary increase in vocal amplitude in response to the presence of background noise. Online regulation of vocalization in response to auditory feedback is one of the essential issues for vocal communication. ![]()
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