Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Songs are stored as snippets in the minds of birds


Caption: White-crowned sparrows, like this one shown singing in a tree, were used in a University of Utah study that examined how birds learn to sing -- and that may shed light on how humans learn to speak. Credit: Franz Goller, University of Utah

University of Utah scientists taught baby sparrows to sing a complete song even though the birds were exposed only to overlapping segments of the tune rather than the full melody. The study provides clues about how musical memories are stored in the brain and how those memories help birds learn to sing.

The results also may have implications for how people learn language, says Gary J. Rose, a University of Utah professor of biology and principal author of the study published in the Dec. 9 issue of the journal Nature.

"There are strong parallels between song learning in birds and speech learning in humans," he says. "Like humans, songbirds learn particular regional dialects, so they represent excellent opportunities to study the physiological basis of language. If we can understand something about how song is represented in their brains, then maybe we can better understand how speech learning occurs in humans and, when it goes awry, how we might go about fixing it."

Study co-author Stephanie Plamondon, a doctoral student in neuroscience, added: "We were able to give the birds just pieces of the song, and they were able to assemble a complete song from those pieces. … A full song or a complete sentence isn’t required to learn the song, only an association between phrases [segments] of the song."

Other authors of the study were Franz Goller, an associate professor of biology; Brenton Cooper, a postdoctoral researcher in Goller’s laboratory; and Howard Gritton and Alexander Baugh, who worked on the study as undergraduates, then as technicians.

This is Your Brain; This is Your Brain with Experience

Songbirds must hear their species’ song when they are young or they fail to learn to sing it. Such birds "produce very simple songs, mostly repeated whistles," Rose says.

Birds learn to sing in stages. First, there is a "subsong" phase in which they babble softly, almost like human infants. Then, they undergo a "plastic" phase when they practice singing for eight or nine months, and "when the bird is producing song and comparing it to the memory he has formed," Plamondon says. After that, the birds undergo "crystallization," which means their song is crystallized or essentially set in stone – at least until the next mating season, when some changes can occur.

The Utah biologists tested a theory dealing with the long-term "auditory memory" formed by young sparrows when they first hear other sparrows sing. Scientists want to know how that memory is stored in the brain, and how that memory is used as the birds learn to sing weeks later.

The complete white-crowned sparrow song has five segments or snippets – researchers call them "phrases" – represented by the letters ABCDE. A is a characteristic opening whistle; B is a "note complex," or several musical notes in a specific sequence; C is a buzzing sound; D is a trilling sound and E is another note complex.

Plamondon says song learning is unlikely to be completely genetic because white-crowned sparrows in different regions have different dialects; they vary in how they assemble song segments. Rose says there is no evidence the birds use short-term memory to remember their song when they are tutored, and it’s unlikely the sparrows carry some sort of internal instructions on how to assemble song segments into a complete song.

Instead, the new study indicates the sparrows’ characteristic song is imprinted on their brain like a long-term memory, and not as a complete song, but in pieces. Rose and colleagues propose that circuits of certain nerve cells only detect – and only need to detect – pairs of song segments (AB, BC, CD, DE) for the birds to learn to sing. That is because each pair of segments overlaps the next, allowing the bird to figure out how to string together the complete melody.

Rose says nerve circuits that detect pairs of song segments are shaped as the birds practice singing. "In many cases, experience shapes the function of the brain," he says. "If humans don’t have normal vision during the first few weeks of life, they become functionally blind. If infants don’t hear speech they obviously won’t learn to produce a verbal language."

He adds: "If experience early in life is essential for shaping the function of the brain, then we need to understand how that happens. And songbirds are one of the few cases other than humans that actually learn their verbal language and have to be tutored." (The others are the cetaceans – whales, dolphins and porpoises – and perhaps bats.)

The Bird Song Experiments

The researchers first recorded songs from white-crowned sparrows in Utah’s Wasatch Range. They digitized the recordings so they could break them into five segments or snippets they called "phrases."

Rose and colleagues obtained permits to capture sparrow nestlings, hand-feeding and raising them in the laboratory in sound-proof cages so they didn’t hear each other.

When the sparrows were 2 weeks old, the researchers began trying to teach them to sing by playing them segments of the complete song in different orders. Separate 90-minute tutoring sessions were conducted for each bird twice daily for 60 days.

In the first experiment, the scientists played one segment or phrase of the sparrow song at a time, separated by 2.5-second silences. They played the segments in reverse order – E, then D, then C, B and A – to control against the birds simply storing what they heard (ABCDE) in short-term memory and repeating it. The nine birds in this experiment could not string the segments together in the right order to sing the entire song ABCDE.

Next, eight young sparrows were played two segments or snippets of their song at a time. Each pair of segments was in the correct order, but the pairs of segments were played backward – DE, then CD, BC and AB.

Because each pair of song segments overlapped another one, these birds were able to string the segments together in the correct order and sing the full song ABCDE. Plamondon says that when birds hear two song segments at a time, they implicitly learn the rules for putting all five segments together.

In a final experiment, five sparrows heard pairs of song segments, with each pair in reverse order: BA, then CB, DC and ED. The birds again learned to string the segments together, but because the segments were reversed, they sang with the segments strung together backward – EDCBA.

Rose says the reversal was surprising because it shows training can overcome sparrows’ innate tendency to start their song with a whistle (represented by A). The sparrows’ ability to construct a complete song from its pieces by knowing how the pieces fit together is comparable to completing a jigsaw puzzle, says Rose. "You don’t have to know what the puzzle picture looks like, just the rules for putting the pieces together," for example, that they fit like locks and keys, he says.

Rose believes birds perfect their songs because they start combining various song segments and retain only those pairs (AB, BC, CD, DE) that match the memory of what they are tutored and reject others (such as AC or EC) that are not reinforced by tutoring.

This may involve interaction between basal ganglia – brain structures that control movement – and nerve circuits that control vocal movements, Rose says, noting birds can sing without basal ganglia, "but they can’t learn and maintain the song." "The relevance of these findings is that this may be representative of how learned sequences of movements of various types work," he adds. "A jazz musician, for example, learns the rules for making transition from one note to the next, and can compose full songs by observing those rules."

Gary Rose | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>