Vocal learning in songbirds bears similarities to human speech development: Novice birds go through a period of "screeching" before learning to imitate songs accurately, much as babies babble before grasping words. Therefore, the new research points to the need for a quantitative study of the effects of sleep on learning in human infants, says Partha Mitra, a theoretical neuroscientist at Cold Spring Harbor Laboratory who participated in the research
The study examined the effect of sleep on song learning in young zebra finches. Individuals of this species are active in the daytime, do not sing in darkness, and develop their song during a critical window of brain "plasticity" between one and three months after hatching.
In order to learn to sing, it's known that young birds must hear an adult song, and through practice, develop their own version of the tune by comparing their vocalizations to a memory template of the song that they "hear in their heads."
Interestingly, researchers have previously found that zebra finch brain neurons involved in vocal learning display patterns of activity while the birds are asleep that are similar to the patterns observed while awake birds are singing. Until now, however, there has been no direct evidence that sleep affects song learning, and if so, how. (See image)
To collect the data used in the study, City College New York behavioral neuroscientists Ofer Tchernichovski and Sbastien Dergnaucourt recorded every vocalization--approximately a million syllables per bird--made by 12 yo
Contact: Peter Sherwood
Cold Spring Harbor Laboratory