Brain Storms about an MRI study of dog brains and Zebra Finches singing in their sleep. SO GOOD!
Animal Brains Transcript:
Welcome to Brian Junk, I’m Amy Barton,
TK: And I’m Trace Kerr, and it’s time for a Brain Storm.
AB: I found a headline, and it said dog brains show that they see their owners as family and they prioritize the smell of humans over everything, and I for sure clicked through, because so many questions and ahhhhh.
TK: I know, it so warm fluffy!
AB: Animal Cognition Scientists at Emory University, they trained dogs to lie still in an MRI. This was my chief question-tell me about dogs in MRI”s, because the people of my family struggle with MRI’s, and so how does that work. They did have some studies where the dogs were tranquilized, or put out, like a little valium, or xanax for people? Dogs too.
Trace and Amy chuckle together in amusement at super chill dogs.
They measure their neural responses to people and dogs, both familiar and unknown, and they found that the dog’s owner’s smell triggered a region in the dog’s brain considered the reward center, and people-ding, ding, ding! Big rewards! Dogs, some rewards, because dogs love other dogs and want to smell them, but people were just..
TK: And all people?
AB: All people, but owners, in particular. They would prioritize people, but your people, your dogs people, are the ones they mainly ping for the most. And studies suggest that dogs feel complex emotions like jealousy and anticipation, so your dog really does probably miss you, and is probably jealous if you smell like other dogs when you get home. And researchers found that happy sounds in particular light up the auditory cortexes in dogs..
TK: The sound of the food hitting the bell? Ding, ding, ding!
AB: Yes! Ahhhhhh! Yup, so the researchers confirmed that dogs interact with their caregivers in the same way babies do with their parents. And when dogs are scared and worried they run to their owners, just as toddlers would, and dogs are the only non-primates to look into your eyes. So they really are looking into your eyes. Your cat’s not. Your cat hates everything.
TK: No, they don’t hate everything, they’re just above everything.
AB: OK. I agree. That would be a better description.
TK:Nice!
AB: Your dog loves you very much. Go pet it.
TK: Arf!
TK: And it’s time, for another Brain Storm! So, Science Magazine has a lot of really cool articles.
AB: I agree;
TK: I stumbled across one by Professor Daniel Margoliash, talking about birds. They seem to sing in their sleep.
AB: Gasps! I love that so much! That’s so Disney!
TK: Isn’t it?
AB: Yes!
TK: Well, now let’s go a little deeper. Zebra Finches in particular, that’s what he was studying. Young male birds seem to learn their song from male adults. So they listen to the male sing their song and they start copying it, and as they age, they change it a little, so everybody’s got their own little song going on. The theory was that all the learning that they did, was when they were awake, was through trial and error. Tried to sing it, ‘eh, it’s no really working for me, try again. Well Professor Margoliash thought they might be rehearsing in their sleep.
AB: Ahhh
TK: Yeah. So there has been some research done on zebra finches and they were anesthetizing them and watching their brains as they slept, but they were anesthetized, and brains work differently so they were doing these experiments in natural sleep, which was novel, and they were playing a recording of the birds song to them while they were sleeping and watching the neurons and found that neurons flowed freely between brain areas that governed singing, and sometimes preceded the song by a beat or so, like the bird was anticipating the tune, even in their sleep!
AB: So what I wonder…I’m super curious if you played..if this would work for people too? I know there are inhibitors that keep people asleep, that make us not move, but I’m curious about the brain function of that. If birds don’t have that, most of us don’t talk in our sleep, but is this the bird equivalent of that? I’m so curious.
TK:Well, but they were making no sound at all, so the bird is not making any sound. So it is like us when we are dreaming, there is some thought that sleep plays a key role in learning, which is part of the reason they were studying this Like what neuroscientists think happens when rats are learning mazes, they’re often somehow they think replaying that when they’re sleeping and practicing it.
AB: It’s like they’re defragging their hard drive.
TK:And humans when we’re learning motor tasks, or even martial arts, because we both do martial arts..
AB: >interrupting rudely but excitedly because she totally gets it now< When I first started Taekwondo if it was a really intense night of learning I would have a hard time sleeping, I would have weird dreams.It was very weird.
TK: Yes! But then the next day you could do whatever that thing was, and maybe be a little more dexterous at it.
AB: Yeah!
TK: So for the birds, it was the singing.
AB: Wow! That’s terrific and makes me really happy!
AB: Want to hear more? We’re on Facebook and Instagram as BrainJunkPodcast, and on Twitter as @MyBrainJunk. Trace and I will catch you next time, when we share more of everything you never knew you wanted to know, and I guarantee you won’t be bored.
Trace & Amy,
I think you have an excellent podcast! I was especially intrigued by this particular episode about animals learning during sleep. Your questions/curiosities are things that I, too, have been curious about. Last year, my colleagues and I published a paper on speech discrimination processing in infants during sleep. I don’t have much more to add other than I thought you might find it interesting. Here is a link to that research if you are curious to learn more:
https://www.colorado.edu/today/2017/05/10/what-baby-hears-while-asleep-matters-more-previously-thought
https://bmcneurosci.biomedcentral.com/articles/10.1186/s12868-017-0353-4
Please keep up the great work! Cheers!
Oooh, that is a terrific topic and raises questions I didn’t know I had. I now wonder, if babies process speach during sleep do adults do so as well? And how much? Just key words like our names and things we would normally tune into if we were in a separate conversation but overheard a key word our brain liked? Headed to read your paper as soon as I am done working on show notes! And thank you for your kind words! AB
UPDATE: I’ve abandoned the show notes and left them in a shambles and have so many new questions about hearing and brain development and how it might relate to your brain’s processing of selective attention, and how did you convince 24 parents to allow you to strap their babies into electrodes? And what about babies who are exposed to a high number of unexpected noises is that training a baby’s brain to be more vigilant-probabilistic processing? Will their sleep be compromised? How does that affect their development? I look forward to reading more about your studies and results! AB
Just being a part of this research has raised questions that I didn’t know I had, which is why I’ve enjoyed this project so much. To answer your questions:
“…if babies process speach during sleep do adults do so as well?”
Yes, adults do as well. Some previous research showing auditory responses in sleeping adults helped with the motivation and design of this study.
“And how much?”
Great question…unfortunately, we really don’t know.
“Just key words like our names and things we would normally tune into if we were in a separate conversation but overheard a key word our brain liked?”
Also a great question, and I can only speculate that key words or other “behaviorally relevant” information would be more likely to evoke an attentional shift than non-relevant information. I’ve often thought that it would be neat to replicate our studies but with the parents’ own speech as the stimuli (e.g., in a random subset of the participants). But, we’re lucky enough to get the data we have now, so adding new test conditions isn’t always feasible.
“…how did you convince 24 parents to allow you to strap their babies into electrodes?”
I am very fortunate that I get to work with Dr. Kristin Uhler on this project; she is the “real brain” behind all of this, and she is fantastic at working with families and organizations that help recruit babies for the study. The motivation behind this research is to discover new biomarkers and to develop new diagnostic tests that help with treatment and rehabilitation strategies in children with hearing loss. When a newborn is identified with hearing loss, we would love to be able to fit that child with a hearing aid or cochlear implant as early as possible to facilitate natural language development. I believe that the families who volunteer for these studies have equally altruistic motives to help advance clinical science. Recruiting volunteers is certainly not easy, but Kristin and her team do an awesome job; her team has now tested over 150 infants since publishing that paper!
“And what about babies who are exposed to a high number of unexpected noises is that training a baby’s brain to be more vigilant-probabilistic processing? Will their sleep be compromised? How does that affect their development?”
I’ve lumped these questions together, because the general answer is that “we don’t know for sure”, but these are definitely questions we have discussed and/or are currently pursuing in our research. We know that excess noise can disrupt our natural sleep cycles and that exposure to excess noise can result in a variety of negative health consequences. I have no reason to think that the developing brain is less susceptible.
A key theme that I’ve repeated a lot lately: just because our brain can do something doesn’t necessarily mean that it should. The brain has many jobs to do during sleep, and I’m not convinced that processing a lot of auditory information should be a priority, and in fact could compromise other sleep functions, as you suggest. However, we would like to better understand those processes, especially when a child has a hearing loss, so that we can better facilitate the brain’s work when needed.
I hope that helps some. Cheers!
Well, I think I know what one of our next Brain Storms is going to be about! Thank you for you kind words and for the super interesting research. Also, the pictures of the infants with all the electrodes on their smiling faces is strangely adorable.