Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Songbird Brains

29.06.2009
When a zebra finch hears a new song from a member of its own species, the experience changes gene expression in its brain in unexpected ways, researchers report. The sequential switching on and off of thousands of genes after a bird hears a new tune offers a new picture of memory in the songbird brain.

The finding, detailed this month in the Proceedings of the National Academy of Sciences, was a surprise, said principal investigator David Clayton, a professor of cell and developmental biology at the University of Illinois.

He and his colleagues had not expected to see so many genes involved, and thought that any changes in gene activity after a bird heard a new song would quickly dissipate.

The new experiments uncovered three distinct profiles of gene expression in the brain. One is typical of a bird sitting alone in silence. A second profile appears quickly just after a bird hears a recorded song – but only if the song is new to the bird. A third profile then emerges 24 hours later, after the song has become familiar.

“I can tell you whether the bird has heard a particular song before or not just by looking at the molecular assay,” Clayton said.

In the study, each bird was kept in quiet isolation overnight before it heard a recording of a new song. The recording was then repeated every 10 seconds for up to three hours.

“The most important thing in its whole life is the sound of another bird of its species singing,” Clayton said.

“And what we found is that 24 hours after the experience its brain is still trying to make sense of what it heard.”

The new study took a broad snapshot of gene activity in the brain. Using DNA microarray analysis, the researchers measured changes in levels of messenger RNAs in the auditory forebrain of finches exposed to a new song. These mRNAs are templates that allow the cell to translate individual genes into the proteins that do the work of the cells. Any surge or drop in the number of mRNAs in brain cells after a stimulus offers clues to how the brain is responding.

Some genes were upregulated within 30 minutes of exposure to a new song, the researchers found, and these included a lot of transcription factors that modulate the activity of other genes. Many other genes were downregulated, including those that code for ion channel proteins, which allow ions to flow into the cell. This could be one way that the brain dampens its response to a powerful stimulus, protecting itself from too much disturbance, Clayton said.

“Whenever something unexpected and different comes along, such as the song of a new bird in the neighborhood, it’s going to deform the listening bird’s neural network,” Clayton said. “And so the system has to basically absorb some of that, make some changes and not be overwhelmed by it. If you push the system around too much, cells die.”

On the other hand, if the system were completely resistant to disturbance, no memory would form, he said.

Twenty-four hours after the initial stimulus, the pattern of activated genes was entirely different from that of the initial response, regardless of whether the bird heard the song again on day two or not, Clayton said. Those genes that were originally upregulated or downregulated had returned to baseline, and a new network of genes was engaged. A major focus of this new network appears to be the regulation of energy metabolism. This suggests a lot is still going on in the brain, Clayton said.

“It’s like we’ve lifted the hood and we’re seeing that these things are just chugging away,” Clayton said. “The bird had this one day of experience and a day later the brain is in a different state. It’s still in high gear. It’s still processing stuff. It’s still reverberating and echoing.”

Clayton is an affiliate of the Institute for Genomic Biology and of the Beckman Institute for Advanced Science and Technology at the University of Illinois.

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>