Dr. Lisa Hiura Transcript
Hello, and welcome to Ask a Scientist. The podcast for both kids and adults to ask scientists questions about anything they want to know. There are so many scientists out there doing a lot of cool scientific research. In the news, we’re constantly hearing about scientists and their new ideas and where those ideas are going to take us in the future. But just who are these scientists? In this podcast, we will learn a little more about who they are and what inspires them as scientists.
I’m your host, Victoria Crystal. Every other week, I’ll sit down with a different scientist and ask them questions written by you, the listeners, and by students from classrooms throughout the country.
Victoria:
Today. Our guest is Dr. Lisa Hiura. She is a post-doctoral fellow in the department of Molecular Cellular and Developmental Biology at the University of Colorado, Boulder.
Thank you so much for being with us today.
Dr. Hiura:
Thank you so much for having me. I love talking science, and I’m happy to have an audience.
Victoria:
Yay. Well, we’ve got an audience and we’ve got a bunch of questions for you.
Dr. Hiura:
Fantastic.
Victoria:
But before we get to those, do you want to give the listeners a little bit of information about you and your career and your research?
Dr. Hiura:
Absolutely. So I’m really interested in the neurobiology of social behavior. All that means is the interactions between the environment and the brain and how that makes it so that certain animals are social with each other, aggressive with each other, bond with each other, pretty much any social behavior I find to be interesting. So I’m trying to become a professor so that I can keep researching those things for my career.
Dr. Hiura:
Awesome.
Well, we’ve got so many questions about all of those things today. And with that, we can go ahead and start. All of these questions were submitted by listeners through emails and on social media.
Victoria:
(Sierra – What are the main chemicals in the brain that cause bonding and hatred? Is there an overlap between the two?)
So this first question comes from listener Sierra. What are the main chemicals in the brain that caused bonding and hatred? Is there an overlap between the two?
Dr. Hiura:
So that’s a really great question. One important thing to consider when we’re talking about animal behavior is how it might be different or similar with human behavior. So yes, animals absolutely spawn and bonds, they have affiliation, they like to spend time together, they sometimes prefer other individuals.
But hatred is a difficult one. That’s definitely one that I think is really common word to use with human behavior. But what does hatred look like in animals? And so really focusing in on the language that we use to describe animal behavior is really important when we’re trying to understand the neural processes that might be driving those behaviors.
But when it comes to any kind of bonding or maybe aggression, aggressions probably would be the most analogous to hatred when we’re talking about animal research. What we primarily study is oxytocin and vasopressin. So a lot of people in my field look at these two molecules that it turns out when they’re circulating in different parts of the brain, depending on the types of receptors that they bind to, they really mediate a lot of different types of social behaviors. But there’s also steroid hormones that are really important, as well as things like dopamine and stress hormones.
So one of the best things about studying social behavior is that really it’s a constellation of different hormones across all different types of cells and brain structures that make it so that an animal chooses to do something like fight another animal versus mate with another animal.
Victoria:
(Joe – I have read that oxytocin is the cuddle hormone in humans. Is this the same in animals? Are there other hormones that promote cuddling or other forms of closeness in people and animals?)
Interesting. That’s cool.
Oh, speaking of it, Joe wants to know, I have read that oxytocin is the cuddle hormone in humans. Is this the same in animals? Are there other hormones that promote cuddling or other forms of closeness in people and animals?
Dr. Hiura:
Yeah. So one of the really cool things about peptides like oxytocin and vasopressin and dopamine is that they’re actually really conservative molecules. And so what that means is that the same molecules that impact these social behaviors in humans are the ones that are also mediating those behaviors in animals. So when we’re talking about oxytocin, we’re really talking about the same molecules in humans and these non-human animals.
And it turns out like oxytocin and vasopressin and dopamine are all involved in the cuddling processes. And in fact, there’s a lot of work that demonstrates that oxytocin and dopamine have interactions. So you actually need both in order to facilitate a lot of those types of pro-social behaviors like cuddling or having a favorite other individual.
Victoria:
(Chris – Is there one particular part of the brain where bonding and relationship formation occurs?)
Oh, cool.
All right. And then this next question comes from Chris. Is there one particular part of the brain where bonding and relationship formation occurs?
Dr. Hiura:
Yeah. So I think for a long time, the way that people thought about brains is that we have these different brain regions and one must be important for vision, and one must be important for aggression, and so on and so forth. And that’s kind of a modular approach to understanding the brain. And as neuroscience is advanced, it’s become really clear that lots of brain processes are actually interacting together in order to make complex behaviors happen.
So when we’re studying something like bonding or relationship formation, what’s most likely happening is that multiple areas of the brain are talking to each other all the time, passing information back and forth. And that’s really what is encoding things in the environment or driving changes in behavior.
And so, it’s not like every part of the brain does everything. There are still regions that seem to specialize in certain types of behaviors. And so that there are particular brain areas, namely those that are important for processing social information, things like the hypothalamus, as well as brain areas that are important for processing reward, things like the ventral tegmental area and the nucleus accumbens. Brain regions have a lot of big, long complex names. So a lot of times we summarize them by calling them reward structures, social structures, so on and so forth.
But it’s really seems to be that’s the interaction of the regions that process social information with the regions that process reward information, when those two things converge is when we get like affiliative behaviors.
Victoria:
Okay. That’s cool. So when people say that like something is a left brain or a right brain activity, is that, you know, kind of the old way of looking at it that you mentioned?
Dr. Hiura:
Yeah, exactly. There are a couple of things like language that actually do have laterality, that’s what we say when we talk about one side of the brain. But really the two hemispheres of the brain are involved all the time. They’re talking to each other. And there’s not really a sightedness in terms of the analytical mind, the artistic mind, or anything like that.
Victoria:
(Andrea – Are all of our social feelings controlled by neurons?)
Okay, cool.
All right. so we’ve got some questions here. Let’s see. Oh, no, I guess just one question here about neurons. Andrea wants to know are all of our social feelings controlled by neurons?
Dr. Hiura:
Yes. neurons are involved in pretty much anything that has to do with perception or behavior or cognition. All of those things are being computationally processed by neurons that are in our brains.
But it’s not neurons alone. Like remembering that the brain is embedded in your body. You can’t really have one system without the other. The brain is the way that we process information, but the body is the way that we interact with the environment. And so all of our social feelings are controlled by neurons. But that information is mediated by parts of our body as well.
Victoria:
Okay. So do the hormones that you mentioned, do those pass through the neurons or interact with the neurons?
Dr. Hiura:
Yeah, so a lot of the hormones are actually created by the neurons themselves, and then the neurons will project to other places and release those hormones depending on certain environments, the control of other peptides or hormonal signals that are coming in, electrical signals from other neurons. So they’re all kind of mediating each other and there’s these big complex networks that determine what hormones go where and when.
Victoria:
(Kelly – How many different animals develop strong relationships? Is that the same as what they call “mating for life”?)
Okay, cool.
All right. Let’s see. So I think our next group of questions are all about animals and different relationships. Kelly wants to know how many different animals develop strong relationships? Is that the same as what they call “mating for life”?
Dr. Hiura:
I love this question. And one of the reasons I love it is because when we think about animals that form strong bonds, we kind of tend to categorize it as animals that do and animals that don’t. But when we look across the animal kingdom, that’s not really the reality. It’s a spectrum of behaviors that we’re seeing. So there’s some animals that are highly social with each other, or only social with a mating partner.
And the frequency of those types of behaviors really depends on the class of animal. And what I mean by that is that animals fall into these different classes. There’s mammals, fishes, birds, and amphibians. And those are kind of the main ones that we talk about. And the frequency of whether an animal kind of forms pair bonds, or raises animals with its, raises young with its partners, depends on which one of those classes that we’re looking at.
So for example, I study pair bonding and biparental care, meaning that two animals, when they mate, they form a really strong bond with each other, they prefer each other over an opposite sex animal of their same species. And they raise their young together.
And it turns out that mammals, when we look at them, only five to 10% of mammals really do that. It’s a really low percentage of mammals. So when think about dogs and cat, those animals don’t form biparental, they don’t do biparental care and they don’t form pair bonds, whereas humans do. So we kind of fall into that smaller subset of the mammalian world, that does have those special behaviors.
But when you look at birds, over 90% of birds actually have the biparental care and pair bonding behavior. So it really varies depending on the type of animal that you’re looking at.
In terms of what they call mating for life, that really touches on different types of what we call monogamy. So monogamy, you might’ve heard it before, it’s like you have one partner and you kind of stick with them. But what’s really important is to be specific about the type of monogamy that you’re talking about. So there’s two types, primarily, sexual and social monogamy. And you can think about sexual monogamy, who you mate with, versus social monogamy, who you live with. So there are animals that will mate specifically with one animal, that’s their whole social world, that’s who they stick with. And others that have a partner that they live within the home. They always go back to them, to the nest. But when they’re out, they’re actually mating with other individuals too.
Victoria:
Hmm. Interesting. That’s cool. Which animals do that?
Dr. Hiura:
Yeah. So I primarily study the socially monogamous prairie voles. And so prairie voles are known for being this like hallmark of love and bonding and monogamy. But really, they’re just socially monogamous. So they have a partner that they pair bond to, they’re extremely attached to, they spend a lot of times with, and oftentimes when they bond in the wild, that’s their partner for life. So we see the mating for life thing. But a subset of these animals will still go out and mate with other individuals if they find them in the wild.
Victoria:
Oh, cool. Interesting. I’d never thought about that before.
Dr. Hiura:
Yeah. Very nuanced.
Victoria:
(Andrea – Why is our brain similar to the rodents? Are there other animals that form bonds like humans?)
All right. Other animal questions. Andrea wants to know why is our brain similar to the rodents? Are there other animals that form bonds like humans, which you touched on a little bit already?
Dr. Hiura:
Totally. So the general idea with the reason for why our brains are the way that they are, is that a long, long time ago, there was probably some ancestral brain from which all other animal brains have evolved and descended. And so if we think about the fact that there was some ancestral brain out there, it has features that we’ve essentially inherited. So when you look across those animal classes, the mammals and the birds and the amphibians and the fishes, they actually have core features that they share across them. This can be regions, this can be connections, but a lot of the times it’s certain proteins or hormones, signaling systems, as well as the morphology of things like neurons. So basic neural functioning is similar across all those different classes.
And so the reason that our brains are similar to rodents is because we essentially share the same ancestors as rodents. I think we are about 90 million years separated, for most recent common ancestor, humans and rodents.
But despite all of that time, the brain is so efficient and works so well in the way that it does, that it seems like selection pressures and changes in the evolutionary environment have made it, so that our brains haven’t diverged really that much.
Let’s see, and then there was a second part of the question, right? Are there other animals that form bonds like humans? So there actually are other primate species too, that form bonds like humans. They have this really cute behavior where they’ll sit next to their partners and their tails will dangle, and they’ll wrap them around each other, kind of like they’re holding hands, they wrap tails, which is the cutest thing I’ve ever heard of.
But yes, other animals, definitely lots of birds, there are frogs that do it, there are fish that do it. It’s actually a pretty common across the animal kingdom, just less common for mammals.
Victoria:
(Diane – How much is the capacity for bonding biological or genetic and how much is learned behavior ( e.g. dependent on experiences with parents, etc.)?)
Cool. Oh, that’s interesting.
All right, let’s see. What’s our next animal question here, or I guess this is sort of a general relationship question. Diane wants to know how much is the capacity for bonding, biological or genetic, and how much is learned behavior, for example, dependent on experiences with parents.
Dr. Hiura:
So this question is pretty much my dissertation, what I got my PhD.
So, pretty much like all behaviors, not just social behaviors like bonding, all behaviors are dependent pretty much on a mix of both, biological and genetic components, as well as environmental or experiential learning components.
So I think when you look at kind of like the common literature, you might come across this nature versus nurture debate, you see it kind of pop up, everyone’s kind of heard those terms. So it used to be that we wanted to describe like what percentage of this behavior or phenotype, which is just what you can observe in an animal, what percentage of those features are based on genetics versus environment.
But that’s actually an older notion and it’s been replaced by this idea called the gene by environment interaction, which is basically when you’re born, you have this genetic profile that’s susceptible to changes in gene expression, depending on features of the environment, things like stress, things like nutrition, how much social interaction that you’re getting. And so when we ask, what is really driving social behavior or different types of behaviors in animals, it’s a combination of what’s typical for their species, so what’s that genetic makeup that is common across animals of that species, and what type of environment are those animals growing up in: are they getting all sorts of care and experience that they need to from their families, or are they not. And depending on what those features are, those two components, that genetics and the environment, interact to make a diversity of different types of phenotypes in animals, both within a species and across species.
Victoria:
Oh, cool. I have two follow-up questions that I just thought of. So some of the questions I’m asking obviously are not on the list, but it’s just like what I’m thinking of.
Dr. Hiura:
I love it.
Victoria:
So is that what people mean when they say epigenetics?
Dr. Hiura:
Oh yes. So epigenetics is a really interesting and currently booming field because we’re getting better at looking at changes in molecular markers that are related to epigenetics.
So for those of you who don’t know, genetics is kind of like a recipe or a cookbook, you’re given these letters or the instructions to make something, right. But epigenetics is essentially how do those instructions look. So if you have pages that are glued together in a cookbook, like you’re not going to be able to read the instructions inside them. And that’s the same type of thing with epigenetics is you have changed the way that the information within a gene is accessible, and if it’s less accessible, then those proteins aren’t going to be transcribed and translated. So you don’t have as much of them. And epigenetics is essentially the way that molecules in our bodies make it so that some genes are more or less accessible than others.
And so social experiences actually do have a really big effect on epigenetic profile for genes that are important for driving social behavior.
Victoria:
Oh, cool.
And then I forgot what my second. Oh, I know. So, if an organism grows up with an environmental factor that influence that their genetics and the way that things are expressed, but then that environmental factor goes away, can it change back to the original way it was?
Dr. Hiura:
So it really depends on the gene and the type of epigenetic mechanism. So there’s a few different epigenetic mechanisms that change the way that genes are accessed and delivered effectively. And so some of those things are reversible and some of them are not.
So, for example, I think it’s a species of wild hamster that depending on the seasonality changes their epigenetic profile, so that their fur color changes with the season.
But there are other epigenetic things that are kind of one hit and doesn’t seem to change back. So, once that occurs, then a gene either is then transcribed, or is from that on not transcribed.
Victoria:
(Diane – Is there variation within as well as between species (e.g. why are some people more social than others)?)
Okay, cool. That makes sense. Okay.
Another question from Diane, is there variation within as well as between species, for example, why are some people more social than others?
Dr. Hiura:
Fantastic question. So I’m actually interested in both of these facets.
One of the things that I’m doing now is actually looking at two different species of voles. One’s a prairie vole, and one’s a meadow vole. They look really similar to each other, but they have completely different social lives. So those are those that variation between species.
But even if we look at prairie voles all in the same colony, they’re in the same building, they’re caught at the same time, born around the same time, there’s still really wide variation in their behaviors and the things that they do with each other.
And so what we’re interested in is looking at the biological mechanisms that drive those species differences, the differences between prairie voles and meadow voles, as well as the interspecific differences. So what is it that makes it so that prairie vole from this home cage is different from a prairie voles in this home cage.
Victoria:
(Sierra – How long does it take for animals to create a bond with another animal?)
Cool.
Okay. Let’s see more animal questions coming up. This one is from Sierra. How long does it take for animals to create a bond with another animal?
Dr. Hiura:
So that’s probably going to depend on the animal that you’re talking about.
I’m sure we’ve all had this experience where we go off to summer camp when we’re a kid and we meet someone for a weekend and all of a sudden, we’re like, feel like best friends in that moment, and then go off and never talk to each other again.
And so it depends on the species as well as the environment. When we talk about prairie voles, which is what I’m most knowledgeable about, it can be as short as living with each other for 24 hours. So in a 24 hour period, if you allow two voles to live with each other, a male and a female, they can form a bond that could last the rest of their lives.
And what is really interesting is that you can actually speed up that process if you give them certain drugs like oxytocin, and you can slow it down if you block the action of natural oxytocin.
Victoria:
(Sierra – How long does it take to form a bond with a shelter animal? Does it take longer if they have had a previous owner or faster since they have made other bonds?)
Wow. I think we have some questions about that coming up later. So, I have some follow-up questions, so hopefully we’ll get those answered later on.
But this is another question from Sierra, a follow-up to that previous question. How long does it take to form a bond with a shelter animal? Does it take longer if they have had a previous owner or faster since they’ve made other bonds?
Dr. Hiura:
So Sierra, that’s a fantastic question. Interspecies bonds, so a bond between individuals of two different species aren’t as commonly studied, I don’t think, as bonds within a species, but it’s a really interesting avenue of research and I hope that more people do it.
So, in voles, once they formed a pair bond, they have a partner, they really like them, one of the features of that bond is that they actually become extremely aggressive towards voles that are not their partner.
But in animals like cats and dogs that you commonly find in shelters, early socialization with their peers, or if they have friends, is really important for social development. So if they’ve had a previous owner that didn’t socialize them, well, they may take longer to bond with you. Or if they had an owner that did socialize them well as they were growing up, then it’s likely that there’ll be more social in the future.
And so it really depends on, again, I’m going to keep repeating myself as it really depends on the species that you’re looking at. So with voles, having a prior bond makes it harder for them to bond later. But with animals like cats and dogs, early socialization seems to be really important for their boldness or their activeness and willingness to interact with each other later on in life.
One more thing is that, there are also some fun studies that have shown that oxytocin levels increase in both humans and dogs when the humans pet the dogs. So even though they’re two completely different species, it seems like they’re undergoing those same kind of hormonal processes and changes when they’re experiencing that social contact. So you’ve been, when you have that situation of looking at bonds across different species, there are still molecular mechanisms that seem to be common between them.
Victoria:
(Sierra – can animals create the same bond with several animals or humans? What makes them have that same bond?)
Okay. That makes sense. I can see that.
All right, let’s see. What’s our next animal question? Another question from Sierra, can animals create the same bond with several animals or humans? What makes them have that same bond?
Dr. Hiura:
So it depends on the type of bond. When I talk about bonding, I typically am talking about a male and a female, a mating pair, that form of pair bond with each other. But there’s also different types of bonds that can happen. There’s the bond between parents and children, mothers and her offspring, between individuals of the same sex and same species, so that’s something that we would refer to as like analogous to friendships maybe in animals.
And depending on the type of bond they can have multiple or just one. So pair bonding is even in the name, it’s two of them. So usually you just have a bond with one individual and don’t have that same kind of selective, really strong bond with other individuals. Unless that bond gets broken and then with enough time you can repair it. So think about relationships, breakups, and then new partners.
And then other instances in which you can have bonds with many individuals, like if a mother mouse or rat has a litter of young, there could be seven individuals there. But they’re still really doting on all of them and not just picking one and thinking you are my bonded infant, so on and so forth.
Victoria:
(Limetra – Does the degree of relationship development between animals influence their success in reproduction and rearing of offspring?)
Okay. Cool.
All right. Let’s see. Oh, a good follow-up question. Speaking of offspring, Limetra wants to know, does the degree of relationship development between animals influence their success in reproduction and rearing of offspring?
Dr. Hiura:
Yes. So this is really critical for biparental species.
So let’s say you have an animal like a cat, and the parent doesn’t necessarily need to form a strong bond with their mating partner because they’re not raising their young together. And so, if a cat doesn’t have a strong pair bond, that’s totally typical and they can rear their young just fine.
But for biparental species, like a lot of birds, cooperation between the parents and taking care of their offspring is really important, crucial, even for the survival of their offspring. So if you have a biparental species that has a strong pair bond, you likely have one parent that can protect the offspring while the other one forges, or one parent to groom the offspring while the other builds the shelter, they can take turns. And that really benefits their offspring being able to survive to adulthood so that they can have their own offspring.
So depending on the species, sometimes you need that turn-taking and for other species, it’s just the mom doing all the work, or even in species like fish, there are fish in which the dad does all the work. The mom lays the eggs, the dad takes over, she’s gone and he raises them.
Victoria:
Cool. When I was a kid, I tried to mate betta fish and it was like I never got it to work cause whenever the female was ready to lay eggs and the dad has to make the nest for the eggs. So whenever the dad made the nest, the female wasn’t laying the eggs and vice versa.
Dr. Hiura:
All that timing coordination is crucial.
Victoria:
(Ryan – Are animals that form strong bonds more social than animals that form weaker relationships?)
Yeah. Let’s see, we’ve got some more animal questions here. This one’s from Ryan. Are animals that form strong bonds more social than animals. That form weaker relationships?
Dr. Hiura:
Fabulous. So it really depends on how we define social. If we’re defining social as pair bonding, then those strong bonds are going to be really important for those individuals.
But there’s other types of social too. So for example, if we look at the meadow vole, which is another type of vole that doesn’t form strong pair ponds, and they’re not necessarily extremely social in the wild, depending on the season. So in the winter, when it gets really cold outside, and there’s a benefit to huddling together for warmth, those animals actually become more social, and they allow that kind of proximity to other individuals. And so they look more social even though they don’t form pair bonds.
So it really depends on kind of the circumstances of those animals, what their environments look like in the wild and how we define that level of sociality. So if we talk about pair bonding, prairie voles will seem extremely social. If we’re talking about huddling with other individuals, meadow voles seem extremely social.
Victoria:
(Andrea – What is the benefit of having friends versus being more independent? Is it better that people are social?)
Okay. That makes sense. That’s cool.
All right, let’s see here. Speaking of other types of social relationships, Andrea wants to know what is the benefit of having friends versus being more independent? Is it better that people are social?
Dr. Hiura:
I think that this is a really poignant and important question in the context of COVID right now. There is so much clinical evidence that socialization and having dependable relationships or support network is beneficial for humans, from psychological components to physiological components, health outcomes, all of those things are impacted by how strong and healthy our social networks are. So for humans, yes, it is better that we’re social.
But remembering that it’s not just the quantity of relationships, how many friends that we have, how many likes on Instagram that we’re getting. It’s also the quality of those relationships. If you have a small knit community of reliable individuals, that’s probably going to be more beneficial than having a lot of kind of loose tenuous relationships with other individuals. So, some of the negatives of being isolated, or stressed out from being alone can be buffered by having those social connections or networks of friends.
Victoria:
(David – How do you look at the brains? Do you use a microscope?)
Okay. That makes sense.
All right. Now we’re switching gears a little bit. There’s a bunch of questions here. That’s all about you, and how you actually do this research. So this first question in that category comes from David. How do you look at the brains? Do you use a microscope?
Dr. Hiura:
So it depends on what we’re interested in in terms of looking at the brain. So there’s a lot of different ways.
Oftentimes what we do is we extract the brain, and we’ll do dissections. So we’ll slice it up really thin, will stain it with certain types of molecules that will make it so that proteins of interest glow in reds or greens, and we can put all that under the microscope and look to kind of look to see connections between cells or the number of a type of cell in a region of interest. So yes, we definitely use a lot of microscopes and a lot of fancy glowing proteins in order to look at the brains.
A couple of other techniques also include using radioactive proteins. And so instead of looking at proteins in fancy colors, what we can do is we can take molecules that are radioactive, that we know bind to certain brain regions of interest, and we wash the brains. A lot of molecular biology is just fancy baths, and brains taking fancy baths. and so we’ve made the brain sections in the solution that has those radioactive molecules. and then we lay literally analog film on top of those sections and the radiation gives off energy that is then transcribed to those films. And then we can look at this film and literally it’s like taking a picture of the brain except for the dark areas are the areas of the brain that we stained for, that contained the proteins of interest. So that’s a bit of an older school technology that’s still really useful today.
Another way that I look at brain specifically, if I’m interested in their activity, it means I can’t look at them once I’ve taken the brain out, because they’re no longer active. And so if I’m interested in the activity, we can actually use viruses and lasers. So I can inject a virus in a specific part of the brain that I’m interested in that carries the code for a protein that changes when the cell is active. So when it’s active, it admits a little bit of light, and then I can put a probe into the brain and use lasers effectively to measure those changes in light as the animal is moving around in its environment. So that’s one of the ways that we can look at brain activity as it’s happening in real time when the animal’s behaving and start understanding, okay, changes in activity in this brain region must be important for XYZ behavior.
And those are kind of the core techniques and technologies that I’m currently implementing in my work.
Victoria:
That is so cool.
Dr. Hiura:
My life feels like a sci-fi movie someday.
Victoria:
Yeah, that’s incredible. Like, I don’t know what I’m more fascinated by, the lasers or the film.
Dr. Hiura:
Right.
Victoria:
(Andrea – What kind of experiments do you do to learn about neurobiology?)
That is super cool. All right. And a good, or a follow-up question to that, you’ve talked about. You know, everything you just said is really cool, but if there’s anything that you can add. Andrea wants to know, what kind of experiments do you do to learn about neurobiology?
Dr. Hiura:
Yes. That is a great question.
So, a long time ago, before we knew as much as we do now about how brains function, a lot of times we would do lesion studies. So that means is you go into the brain and you might lesion an area, and then you see how an animal’s behavior changes after that. If it’s different after you damaged a brain area, you can probably assume that that brain area is important for that behavior.
And another example, besides doing those type, making lesions on purpose, is you can look at animals or people that seem to have some sort of behavioral or cognitive impairments and then scan the brain and see, is there anything about this brain that looks abnormal?
So for example, Phineas Gage is a really famous example in the psychology literature of how we found out that the frontal cortex is really important for emotional regulation. So Phineas Gage was this individual that used a tamping iron to tamp down a TNT, and it turns out the TNT exploded and the rod shot through his frontal brain, and he survived the incident, but then his personality and his emotions completely changed. And so from that, we knew that, okay, it turns out that the frontal cortex is really important for that type of behavior.
And so, it’s that two-way street: we can look for behavioral abnormalities and then look for brain differences that might weigh them, or we can manipulate the brain and look for behavioral changes.
And so after those types of more like crude lesion studies, our techniques and technology have gotten much more sophisticated in contemporary, modern day neuroscience. So instead of figuring out, okay, if we lesion in this region, what are the behavioral changes that happen? We can actually start looking at the connections between regions, or the functions of specific hormones or peptides in specific regions. We have ways that we can use the lasers I was talking about before to activate only certain cells in certain time periods to see what does this cell do when the animals interacting in this context versus another context.
Another way to look at neurobiology, and its relationship to behavior, that I did for my dissertation work, was I raised animals at different types of early life environments, and then looked at the differences in their brains as adult. So it doesn’t always taken manipulating the brain specifically to see if there are changes in the brain as a function of whatever manipulation. Sometimes you can do something as simple as raised animals with their dads or without their dads, and look at their brains later on in life to see how important was that environmental effect for things like receptor density, the number of neurons, things like that.
Victoria:
(Chris – In your research, can you influence animal bonding formation by giving them high doses of particular hormones or drugs?)
(Aaron – How do you give the animals the chemicals? Shot? Pills? Does it hurt the animals?)
Cool. Oh, that’s so interesting.
All right, let’s see here. speaking of things you do in your research, Oh, this is getting at that question that we mentioned earlier about, you know, giving the hormones. So Chris wants to know, in your research, can you influence animal bonding formation by giving them high doses of particular hormones or drugs? And then kind of going along with that Aaron’s question.
How do you give the animals the chemicals? Shot? Pills? Does it hurt the animals?
Dr. Hiura:
So these are all really important questions. And I’m really glad that audiences are intuiting some of the results that we have from our field.
So first, can we manipulate bond formation with drugs? Yes. that’s one of the most exciting things that I think is coming out of the field is that we’re getting really good at delivering drugs or certain types of stimulations to specific brain regions and seeing how that impacts pair bonding. So I mentioned before that oxytocin and dopamine, those two things are needed together in order to form pair bonds or accelerate them. We have techniques now that we can deliver drugs to very specific parts of the brain instead of the whole body.
So I’m kind of gonna mix my answer here with Chris and Aaron, is that there are some chemicals that can be inhaled, so gases; other chemicals that can be delivered subcutaneously, so shots; other chemicals that can be added to water or food, so the animals just consume them.
But if we’re interested in the effect of a drug on a really specific part of the brain, we don’t just want to bathe the entire body in that chemical. Right. Because then we won’t know if the behavioral change is an effect of that drug on a different body structure or different part of the brain, so on and so forth. And so, those types of drug treatments will require surgeries so that we can really precisely inject drugs of interest, like literally oxytocin or dopamine or drugs that block oxytocin and dopamine receptors, and look at changes in pair bonding.
So when we give oxytocin to voles specifically in some of those rewards structures, instead of it taking 24 hours for the voles to form a bond, it can take 12 hours. So we can really accelerate that cycle. If we give them an antagonist, meaning a drug that blocks those oxytocin or dopamine receptors in those reward structures, we can stop a bond from happening when it would have happened otherwise. So we can do those manipulations.
And for any type of drug manipulation, before they can be done, labs like ours or any science lab that uses animals, has to work closely with veterinarians and other governing bodies of the universities to figure out what is the safest and most pain-free way to deliver those drugs. Because we want to treat our animals with as much respect and compassion as possible. Working with animals is a privilege and not a right. And so we want to make sure that anytime we’re doing manipulations that could potentially cause harm to the animal that we’re doing them in the most humane way possible.
And then after manipulations like surgeries or injections happen, especially those directly in the brain, we monitor the animals really closely and we actually give them pain medication. They get some of the pain medications that our pets at home would get, or that we would get, in a hospital, in order to reduce any kind of that discomfort that they might be feeling. So one of the jokes I like to make is that oftentimes the animals that we see in these labs or science experiments are getting better healthcare than we are.
Victoria:
Oh man. That is really good to know. Cause when you said surgeries and I was like, Hmm, I wonder how that works. So that’s good to know. That’s awesome.
Dr. Hiura:
Yep. Lots of training and like responsible animal handling courses. Everyone that works with animals is having to essentially take a lot of modules and practice working with the animals before they can do any type of experimental thing.
Victoria:
Okay. That makes sense. Do you name the animals or would that be too, would that make you too attached?
Dr. Hiura:
Yeah. So, there are animals in the lab that I’ve been in before that have names that kind of become lab mascots. When you work with animals really closely, I think it’s kind of our human cultural nature to want to give them names. There are definitely contexts in which it should be avoided because giving them names can make it so that you become more attached to the animals.
But it also depends on the nature of the study and the type of animals that you work with. If you have a primate colony, you’re probably not, you know, calling the animals very frequently, they’re going to live long lives. So giving them names is totally normal. Whereas mouse colony, when you have these shorter lived or terminal studies, oftentimes they’re just numbers.
Victoria:
Yeah, that makes sense. When I was in a geochemistry lab at CU, we obviously didn’t have any animals that we worked with in our lab, but we named all of the machines in the lab.
Dr. Hiura:
Oh, that’s, yeah, definitely. Computers have names, pipettes have names.
Victoria:
Yeah. Name all the inanimate objects.
Dr. Hiura:
Exactly.
Victoria:
(Jane – How did you get interested in studying close relationships?)
All right. And then this is our very last question. Jane wants to know, how did you get interested in studying close relationships?
Dr. Hiura:
I’m always interested in knowing how people got into the jobs that they did. So I’m really happy to hear this question.
When I was a kid, I was obsessed with animals. I would chase squirrels. If I found a frog, I would pick it up to my parents’ chagrin. I was just always really, really interested in animals. I was the type of kid that if you took me to a zoo, I could spend two hours just staring at the same exhibit, just watching penguins. Like I just always wanted to know what they were doing and why. I’m really interested in observing the world around me. I’ve also really always been interested in psychology and understanding, wanting to know why people do the things that they do.
And then getting to college and realizing there’s an entire science of trying to understand why people do the things that they do. And so kind of combining my love for observing animals and my interest in understanding people and their relationships kind of led me to this intersection of, oh wow, they’re animal systems that actually have close relationships and interesting brain functions and I’m allowed to study them.
So it was kind of combining all those different interests together. And it turns out that there’s a field specifically for the neurobiology of social behavior. And discovering that that was an option for a career was life-changing for me.
Victoria:
Oh, that’s awesome. That’s a great origin story.
So I guess I kind of lied when I said that was the last question. I do have a question. Do you have any questions of your own for the listeners?
Dr. Hiura:
Oh, do I have questions of my own? Yeah. So, I guess one thing that I’m always wanting to know, when we go into academia or we have a lot of like courses, and papers that we read, we can really get kind of steeped in our own philosophies. And so I’m curious what the listeners know generally about brain function and animal behavior. Like what do they know about how closely related we are to other animals? What do they find interesting? It seems like bonding kind of strikes a chord with a lot of people. We’re all kind of interested in, you know, things that we do and the capacities that we have. But how closely do people actually think about, you know, our role as animals in the world? We like to think of ourselves sometimes as special, humans are different, ensure that they have things that they can do that other animals can’t, but we really are just animals in the animal kingdom. So do listeners think about that? And what do they think about that?
Victoria:
Awesome.
And do you have any, like professional social media accounts, or anything that they can follow you on?
Dr. Hiura:
Yeah, you can find me on Twitter. I think @LHiura. And I’m always happy to answer questions, even if you just Google me and send me an email. I love talking science and I would love to talk to anyone.
Victoria:
Awesome. Sounds great. So if listeners have answers to that question, that’s how you can get in touch.
Thank you so much for joining us today. I’ve really enjoyed having you.
Dr. Hiura:
Thanks for having me. It’s been a pleasure to chat.
Victoria:
Yeah, this is great.
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