Science: by implanting memory into the brain, birds can learn to sing

October 5, 2019 / BIOON / - -- animals learn by imitating behaviors, such as when a baby animal mimics the voice of its mother, or when a young male zebra finch mimics the courtship of an older male Tutor (usually its father) In a new study, researchers from the Southwestern Medical Center of the University of Texas in the United States identified the neural circuit that grass finches use to learn the length of singing syllables, and then used photogenetics to manipulate the neural circuit to build a false memory for young birds to use to make their courtship sounds in adulthood The relevant research results were published in the Science Journal on October 4, 2019, with the title of "perception of memories that guide vocal learning in the songbird" Picture from utsw In order to learn from observation, you have to create a memory of someone doing something right, and then use the sensory information to guide your motor system to learn how to perform the behavior We really don't know where and how these memories are formed " The authors "address the first step in the process, which is how you form the memory that will then guide you in carrying out the behavior." Todd Roberts, a neuroscientist at the University of Texas Southwestern Medical Center and co-author of the paper, said, "our initial goal was actually much more moderate." Initially, Wenchan Zhao, a graduate student at Roberts lab, set out to test whether disrupting this neural activity can block the ability of the birds to form interactive memories when young finches interact with male Mentors (the older birds in the following) She uses light to manipulate genetically engineered cells that are sensitive to light in a brain circuit known to be involved in song learning in young birds When the young finches spent time with their older birds, Zhao activated the genetically engineered cells by shining light on their brains, while the young finches, as controls, lived alone Later, she noticed that the songs of these so-called control birds were different - not only from those of young birds who had never seen the older birds, but also from those of young birds who interacted with the older birds Once Zhao and her colleagues heard the unusual song, Roberts said, they decided to "test whether the activity in this neural circuit is enough to implant memory." The researchers stimulated the neural circuits of young birds for five days with 50 or 300 milliseconds of light genetic pulses, during which time they usually interacted with older birds, but not with adult males When these young birds grow up, they sing adult courtship songs that are consistent with their exposure to light Young birds exposed to short pulses of light sing for about 50 milliseconds as they grow up, while those exposed to extended pulses maintain longer notes as they grow up Some song functions, including pitch and the level of noise in songs and sound stanzas, do not appear to be affected by optogenetic manipulation As another measure, entropy is similar to the amount of information carried in communication It can be used in young birds who normally receive guidance from older birds and those who receive 50 milliseconds of photogenetics There is no distinction between young birds exposed to pulses, but the entropy of songs sung by young birds who are coached by older birds is greater than that of songs sung by young birds who live alone and those who are exposed to 300 millisecond light pulses Although the manipulation of this neural circuit affects the duration of the sound in the grass sparrow songs, other singing behavior elements (including the schedule of singing occurrence, the frequency of bird practice and the social occasions in which they finally use these songs) are similar to those of young birds who learn from adult birds The researchers then determined that when these young birds were exposed to light while interacting with singing older birds, the songs they sang in adulthood were more like those that were only exposed to light, suggesting that photogenetic stimulation could replace the guidance of older birds When the researchers disrupted this neural circuit before young birds met their older birds, they did not attempt to mimic the courtship songs of adulthood But if these young birds had the opportunity to interact with the older birds before their neural circuits were destroyed, they would have no problem learning songs This finding points out that this neural circuit plays an important role in the formation of initial memory of vocalization time, but it does not play a role in long-term memory storage, so it can be used to guide the formation of songs "What we can implant is information about the duration of syllables that birds want to try to learn how to sing," Roberts told scientists But he said birds need to pay attention to many other features when learning songs, including pitch and how to put syllables in the right order The next step is to identify neural circuits that carry other types of information, and to study the mechanisms that encode these memories and where they are stored in the brain Sarah London, a neuroscientist at the University of Chicago, agreed that the strategy used in the study could serve as a template to distinguish where other features of the songs learned came from In a broader sense, however, she said, the research on songbirds is linked to our broader prospects for learning and memory understanding She explained that song learning "is a complex behavior that requires multiple brain regions to coordinate their functions during long-term development In any case, the brain is changing, and most importantly, the brain's behavior is changing " She added that studying the generation of mottled tits' singing can provide insight into "how mature neural circuits are affected by the environment," including the internal and external social environment of the brain "This is a truly unique opportunity, not only for songs, but also for languages, and for learning in a larger context - children trying to understand and adopt behavior patterns that fit their time and place." (bio Com) reference: 1 Wenchan Zhao et al Perception of memories that guide vocal learning in the songbird Science, 2019, DOI: 10.1126/science.aaw4226 2 David F Clayton Learning birdsong by animation Science, 2019, doi:10.1126/science.aaz1552 3.Researchers Implant Memories in Zebra Finch Brains https://www.the-scientist.com/news-opinion/researchers-implant-memories-in-zebra-finch-brains-66527