Songbirds' Method of Learning Tunes Could Yield Better Understanding of Human Diseases
A new study into how songbirds learn to sing could help scientists understand more about Parkinson's disease.
Parkinson's, along with Huntington's disease and a host of others, are linked to a disorder in the basal ganglia, an area of the brain involved with motor learning.
Writing in the journal Neuron, a team of scientists details their study of songbirds' ability to learn songs, which happens in a method similar to how humans learn how to speak.
Songbirds have been documented memorizing a song taught to them, and then practicing that song until they produce a similar one, the researchers said. This learning style is dependent on the basal ganglia.
"As adults, they continue to produce this learned song, but what's interesting is that they keep it just a little bit variable" said Sarah Woolley, a biology professor at McGill University. "The variability isn't a default, it isn't that they can't produce a better version, they can - in particular when they sing to a female. So when they sing alone and their song is variable it's because they are actively making it that way."
Woolley and her research collaborators used this change in song variability to study how the activity of cells in different parts of the brain altered their activity depending on the social environment.
"We found that the social modulation of variability emerged within the basal ganglia, a brain area known to be important for learning and producing movements not only in birds but also in mammals, including humans" Woolley said in a statement. "This indicates that one way that the basal ganglia may be important in motor learning across species is through its involvement in generating variability."
Songbirds were chosen for this study because they have cortical-basal ganglia circuit that is specific for singing, unlike other species that have their basal ganglia linked to other brain cells and circuit pathways.
"The evolution in songbirds of an identifiable circuit for a single complex behavior gives us a tremendous advantage as we try to parse out exactly what these parts of the brain do and how they do it," Woolley said.
In the future, the research could be used to better understand how language and flexibility in motion becomes affected by diseased such as Parkinson's.
"These are the kind of questions that we are now starting to pursue in the lab: how variability is affected when you radically manipulate the system akin to what happens during disease," Woolley said.