Featured Research

from universities, journals, and other organizations

Scientists image brain at point when vocal learning begins

February 19, 2010
Duke University Medical Center
Scientists have imaged living juvenile songbird brains at the moment the brains heard a tutor's mating song. Instead of staying plastic and dynamic after hearing the song, the bird's neurons snapped into a framework nearly immediately, surprising the researchers. Some birds were unable to learn or learn it well, indicating they were past their prime learning window.

High resolution in vivo images of neurons and associated dendritic spines in the brain of a juvenile songbird during the initial stages of song learning. Images taken by Todd Roberts.
Credit: Todd Roberts/Duke University Medical Center

Duke University Medical Center scientists crowded around a laser-powered microscope in a darkened room to peer into the brain of an anesthetized juvenile songbird right after he heard an adult tutors' song for the first time.

Related Articles

Specifically, they wanted to see what happened to the connections between nerve cells, or synapses, in a part of the brain where the motor commands for song are thought to originate.

In the first experiment of its kind, they employed high resolution imaging to track changes to individual dendritic spines, important points of contact between nerve cells.

"We expected to see the building of new spines and loss of old spines accelerate when the juvenile heard a tutor's song for the first time," said senior author Richard Mooney, Ph.D., a Duke professor of neurobiology. "Instead, we saw exactly the opposite: hearing a tutor song rapidly stabilized previously dynamic synapses."

Juveniles with initially higher levels of spine turnover before hearing the tutor song subsequently learned more from their tutors. Because the scientists studied birds during their late adolescence, some may have been past their optimal learning period. "Juveniles in which spines were already highly stable weren't able to learn from their tutors," said Todd Roberts, Ph.D., a postdoctoral fellow in the Department of Neurobiology who is lead author on the study, which was published online in the journal Nature on Feb. 17.

In the "learners," hearing a tutor song rapidly stabilized spines.

Roberts said they were expecting to find higher "plasticity," the brain's ability to remodel connections in response to learning or injury. "We thought we would see an initial stage of higher plasticity, because it can take weeks or even months for a juvenile to copy the tutor song." .

The findings provide fundamental insight into how the brain changes during the juvenile's critical periods for behavioral learning. They also can guide future research aimed at restoring plasticity to synapses after the critical period closes, an important therapeutic goal in helping people regain function after an injury like hearing loss or stroke, Mooney said.

The researchers studied juvenile male songbirds that were kept only with females, which do not sing. They had been exposed to other calls and noises, but not the critically important song of a male tutor. "The adult male's song is a signal that the juvenile's brain seems to crave," Mooney said.

As to why this rapid stabilization of dendritic spines might be important, Mooney said that the songbird brain, like people's brains, is learning for an important goal, which is to perform a highly precise skill. "Many skills, including communication skills, require great precision if you want to stay in the gene pool," Mooney said. "A male songbird has to learn to sing precisely or he won't attract a mate."

The finding that a stable network of synapses rapidly forms after a young bird hears the tutor song suggests that an experience can act in a young brain to build stable connections between neurons, providing a foundation for learning new behaviors, like singing or speaking.

Roberts detailed the painstaking way that he and colleagues set up the experiment and imaged the individual dendritic spines. They used an engineered virus to infect certain nerve cells, which then expressed green fluorescent protein. "Hit with the right wavelength of light from a powerful and concentrated laser beam, the neuron glows and we can even see its dendritic spines, which are tiny components of excitatory synapses," Roberts said. The same neurons and spines were tracked and photographed for up to a month.

Co-authors included Katherine A. Tschida and Marguerita E. Klein of the Duke Department of Neurobiology. The study was funded by the National Science Foundation (NSF), the National Institutes of Health (NIH), a National Research Service Award from the NIH, an NSF pre-doctoral award and the Howard Hughes Medical Institute.

Story Source:

The above story is based on materials provided by Duke University Medical Center. Note: Materials may be edited for content and length.

Journal Reference:

  1. Todd F. Roberts, Katherine A. Tschida, Marguerita E. Klein & Richard Mooney. Rapid spine stabilization and synaptic enhancement at the onset of behavioural learning. Nature, 2010; 463 (7283): 948 DOI: 10.1038/nature08759

Cite This Page:

Duke University Medical Center. "Scientists image brain at point when vocal learning begins." ScienceDaily. ScienceDaily, 19 February 2010. <www.sciencedaily.com/releases/2010/02/100217131128.htm>.
Duke University Medical Center. (2010, February 19). Scientists image brain at point when vocal learning begins. ScienceDaily. Retrieved March 6, 2015 from www.sciencedaily.com/releases/2010/02/100217131128.htm
Duke University Medical Center. "Scientists image brain at point when vocal learning begins." ScienceDaily. www.sciencedaily.com/releases/2010/02/100217131128.htm (accessed March 6, 2015).

Share This

More From ScienceDaily

More Mind & Brain News

Friday, March 6, 2015

Featured Research

from universities, journals, and other organizations

Featured Videos

from AP, Reuters, AFP, and other news services

Suicide Rates Up For Young Women In U.S.

Suicide Rates Up For Young Women In U.S.

Newsy (Mar. 6, 2015) According to a report from the CDC, suicide rates among young women increased from 1994 to 2012 while rates among young men have decreased. Video provided by Newsy
Powered by NewsLook.com
Former NFL Players Donate Brains to Science

Former NFL Players Donate Brains to Science

Reuters - US Online Video (Mar. 3, 2015) Super Bowl champions Sidney Rice and Steve Weatherford donate their brains, post-mortem, to scientific research into repetitive brain trauma. Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Alzheimer's Protein Plaque Found In 20-Year-Olds

Alzheimer's Protein Plaque Found In 20-Year-Olds

Newsy (Mar. 3, 2015) Researchers found an abnormal protein associated with Alzheimer&apos;s disease in the brains of 20-year-olds. Video provided by Newsy
Powered by NewsLook.com
This Nasal Treatment Could Help Ease Migraine Pain

This Nasal Treatment Could Help Ease Migraine Pain

Newsy (Mar. 2, 2015) Researchers gave lidocaine to 112 patients, and about 88 percent of the subjects said they needed less migraine-relief medicine the next day. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.


Breaking News:

Strange & Offbeat Stories

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News


Free Subscriptions

Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile

Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?

Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins