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The Bengalese finch is a domesticated songbird derived from the white-rumped munia, Lonchura striata. Research papers often designate it Lonchura striata var. domestica. The name identifies a domesticated form, rather than by itself establishing a separate wild species. Its learned birdsong makes it useful for experiments on auditory feedback and behavioral change.^[ref]

In 2007, Evren C. Tumer and Michael S. Brainard tested whether small variations in otherwise stable adult birdsong could support learning. A computerized system monitored the pitch of selected song elements and disrupted auditory feedback for a selected subset of renditions. The birds shifted the targeted pitch to avoid the disruption, while other song features were relatively preserved. Delaying the feedback prevented the adaptive shift in the reported comparison.^[ref]

For an illustrative version of the logic, suppose feedback is disrupted only when one chosen song element falls below a preset pitch. Later singing above that threshold would reduce disruption. The key comparison is the distribution of that element before and after contingent feedback, together with appropriate feedback controls. A shift need not mean the bird acquired an entirely new song; it can reveal adjustment of one feature within a practiced behavior.

Evren C. Tumer is a researcher whose work with Michael S. Brainard tested how small variations in a practiced skill can support further motor learning. Their 2007 study examined adult Bengalese finch song, which is highly repeatable but still varies slightly between performances. They asked whether this variation was merely unavoidable noise or could provide alternatives from which learning selects.^[ref]

A computerized system measured the pitch of selected song elements and delivered an auditory disruption for only some of the naturally occurring variations. The birds shifted pitch to avoid the disruption, with changes restricted to the targeted features. The experiment therefore linked a measurable action, its outcome and a later change in performance. It showed that a stable adult skill can contain useful variation on which adaptive motor learning operates.^[ref]

Michael S. Brainard is a researcher in neuroscience who studies how experience shapes sensorimotor learning. His work uses songbirds to connect measured behavior with the activity of the nervous system. Song offers a particularly useful task because a young bird first hears a tutor and then uses auditory feedback to refine its own performance.^[ref]

In a 2009 study with Samuel J. Sober, adult Bengalese finches heard electronically shifted pitch through custom headphones. The birds changed their own pitch in the opposite direction and returned toward baseline when normal auditory feedback resumed. Thus an apparently stable adult skill could be actively maintained by feedback control, rather than being an unchanging motor program.^[ref]

Samuel J. Sober is a researcher in motor learning and the control of skilled movement. His laboratory combines recordings from neurons and muscles, behavioral experiments and computational analysis to investigate how the nervous system produces and adjusts movement. These approaches connect an animal's observable performance with candidate mechanisms for controlling it.^[ref]

With Michael S. Brainard, Samuel J. Sober tested whether adult birds continually correct vocal errors. A microphone captured Bengalese finch song and processing equipment altered its pitch before playing it through headphones. Compensatory changes in the birds' pitch showed adjustment to a measurable error in auditory feedback. Unlike deafening alone, this manipulation supplied an error that a change in behavior could reduce.^[ref]