Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Practice as well as sleep may help birds learn new songs

15.12.2008
Research looks at brain in the first moments of learning

The reorganization of neural activity during sleep helps young songbirds to develop the vocal skills they display while awake, University of Chicago researchers have found.

Sleep is well known to have a role in a broad range of learning processes studied in humans, including acquiring complex skills such as video game playing and learning new speech dialects. However, the neural mechanisms involved in the nighttime consolidation of learning are not well understood. To study this, researchers turned to an animal model system, the developmental learning of song in songbirds, which long has been known to share features with learning speech and language.

Sylvan Shank, a recent Ph.D. graduate in Psychology, and Daniel Margoliash, Professor in Organismal Biology & Anatomy and in Psychology, report in this week's issue of Nature that when young zebra finches listen to an adult tutor's song and then practice singing, the activity of premotor neurons in the brain is altered during the following night's sleep. The newly formed pattern of spikes in nighttime activity carries information both about the tutor song and auditory feedback the birds hear while singing. These nighttime changes lead to improvements the young birds' singing that can be observed the following day.

The study, described in the paper, "Sleep and Sensorimotor Integration During Early Vocal Learning in a Songbird," is the first direct observation of the nighttime activity related to vocal learning.

"This study takes big steps forward in finding out how sleep impacts learning," Margoliash said. "We looked at juvenile birds at the first moments of learning. We gained insight into the role of auditory information in structuring sleep activity, which in turn, we speculate interacts with daytime activity to drive vocal learning.

Since the changes occur in the region of the brain that drives singing during the day, but occur prior to the changes in singing, this discovery provides a compelling hypothesis for how this learning might happen. Juvenile songbirds show a complex, sleep-dependent circadian patterns of singing that have been observed during developmental vocal learning.

Their songs have less structure each morning and regain their complexity each afternoon. This daily pattern of variation is important for song learning—birds that have the greatest variation early in development are the ones that ultimately learn the best.

"We now have a new model for how this works," said Margoliash. "At night, the auditory information that the bird was exposed to during the day is reactivated, [carried by the spontaneous activity of neurons], changing the structure of the neural networks. These changes interact with changes during the day as birds listen to tutor songs and practice singing." The authors suggest that reactivation of sensory information at night might be a general mechanism for learning a new skill.

In previous work, Margoliash and his team identified places in the brain where nighttime activity is reactivated. In adult birds, individual cells spontaneously emitted patterns of bursts during sleep that were very similar to the burst patterns emitted when the bird sang during the day.

In the current study, the University team was able, for the first time, to look at juvenile zebra finches. Using microelectrodes, the team observed changes in neuronal activity during sleep in a region of the young zebra finch brain involved in singing—the acropalium (RA).

Shank and Margoliash first looked at the effects of exposing birds to different tutor songs. They then extended that work to the role of auditory feedback in driving learning. They wanted to see whether changes in the brain brought on during sleep after exposure to a new song were reinforced by practice as well as daytime listening. They theorized that the interaction of the listening followed by practice and sleep consolidation could explain how birds learn to sing new calls.

To test the role of auditory feedback on the bird's learning, the team used white noise at 100 decibels to prevent the birds from hearing themselves. In subsequent tests of their brain activity, the team found no increase in the activity after the exposure to white noise, even if the birds had listened to tutor songs. This finding demonstrated the importance of auditory feedback; after the white noise was eliminated, the birds began to learn normally.

"There is a very famous theory called the 'template theory' of birdsong learning," Margoliash said. "This theory postulates that a sensory template is formed when listening to an adult tutor, and that this template is then used to evaluate auditory feedback. We knew neither the form nor the mode of action of the template. Now we understand that the template can influence learning via sleep, and that new template information is rapidly distributed throughout the brain."

Neurons in RA do not exhibit auditory activity during the day, yet their nighttime activity patterns reflect auditory signals. Margoliash speculates that "perhaps dreams are so compelling because additional areas are recruited to process the sensory experience."

William Harms | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Life Sciences:

nachricht Research team of the HAW Hamburg reanimated ancestral microbe from the depth of the earth
01.03.2017 | Hochschule für Angewandte Wissenschaften Hamburg

nachricht Researchers Imitate Molecular Crowding in Cells
01.03.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

A better way to measure the stiffness of cancer cells

01.03.2017 | Health and Medicine

Exploring the mysteries of supercooled water

01.03.2017 | Physics and Astronomy

Research team of the HAW Hamburg reanimated ancestral microbe from the depth of the earth

01.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>