Zebra finches (Taeniopygia guttata) are passerine birds native to Australia.
One of the evolutionary challenges these birds face is they must learn their song from their parents and siblings since it’s not innate.
Researchers wondered whether sleep might also play a role in song acquisition. Could sleep help juvenile finches internalize the acoustic patterns they hear from their family members and commit them to long-term memory? Could these birds learn their song at least in part by rehearsing it in their minds while asleep?
When researchers mapped the neural patterns that emerged in the same brain region when the finches practiced their song while awake and compared them to the patterns elicited during sleep, their findings were astonishing.
They discovered that the pattern elicited by the act of singing while awake was an exact structural replica of the patterns elicited during the period of sleep marked by sudden bursts of high-level neural activity.
The match was so perfect that these patterns matched one another note-for-note. Zebra finches learn their song not only by practicing it out loud while awake but also by mentally replaying it while asleep without making a chirp.
During replay while asleep, the birds’ vocal cords expand and contract exactly as they do during play. Aside from mentally rehearsing their song during sleep, they also practice the bodily skills needed to actualize their song.
They dream their song to life.