Oct. 4 (UPI) -- Scientists have implanted memories in the brain of a baby bird, helping the fledgling learn to sing.
Just as infants learn to talk by mimicking the sounds of their parents or caregivers, zebra finches learn to sing by copying the melodies of their feathered fathers.
Scientists haven't been able to figure out exactly how this learning process works in the brain. How are memories of a parent's vocalization encoded and incorporated into the learning process?
The latest research, published Friday in the journal Science, proved memories can be implanted in the brain to teach vocalizations.
"This is the first time we have confirmed brain regions that encode behavioral-goal memories -- those memories that guide us when we want to imitate anything from speech to learning the piano," Todd Roberts, a neuroscientist with with the University of Texas, Southwestern's O'Donnell Brain Institute, said in a press release. "The findings enabled us to implant these memories into the birds and guide the learning of their song."
For the study, scientists used light to manipulate two regions of the brain in bird subjects that had never heard their fathers sing. The birds learned to sing, one syllable at a time, through memories implanted by the researchers. The length of the syllable was controlled by the amount of time light activated the neurons: the longer the light was directed onto the neuronal target, the longer the syllable.
"We're not teaching the bird everything it needs to know -- just the duration of syllables in its song," Roberts said. "The two brain regions we tested in this study represent just one piece of the puzzle."
Though the birds learned to sing, their songs weren't fully-formed. The scientists were not replacement nor tutelage of a bird's father.
But scientists expect future experiments to reveal regions of the brain responsible for other aspects of the song learning process.
"If we figure out those other pathways, we could hypothetically teach a bird to sing its song without any interaction from its father," Roberts said. "But we're a long way from being able to do that."
Ultimately, Roberts and his colleagues hope their efforts to map the neurons responsible for song learning in birds will inspire treatments for humans with autism or other neurodevelopmental conditions.
Scientists have struggled to find the areas of the brain where memories involved in learning are encoded, but researchers were able to locate key neurons by using light to test connections between sensory motor areas of the brain. Researchers studied the interactions between the NIf and HVC brain regions, both of which are linked to learning through auditory experience.
The tests showed NIf neurons aid the formation of syllable-specific memories, but that the memories are stored elsewhere. When scientists cut off communication between the NIf and HVC regions, birds that had already learned the song could still perform, but birds that were trying to mimic their fathers were unable to copy the vocalizations.
Researchers aim to better understand the flow of information into and out of the HVC region through followup experiments.
"The human brain and the pathways associated with speech and language are immensely more complicated than the songbird's circuitry," Roberts said. "But our research is providing strong clues of where to look for more insight on neurodevelopmental disorders."