Tuesday, February 6, 2024

Unreadable: Podcast Transcript - February 2024

In this month's episode, we revisit an old favorite, The Science of Love. This episode was originally published in 2019 and remains one of our favorite episodes. 

Did you know that prairie voles are monogamous? In this episode, Ross interviews Dr. Larry J. Young of Emory University about what studying prairie vole relationships can teach us about human relationships.



Ross Gericke: Hello and welcome to Unreadable, the official Forsyth County Public Library podcast for library news, upcoming programs, and recommendations. I’m your host Ross Gericke, the Branch Manager at Hampton Park.

For this episode, we will be rerunning one of our most popular episodes from way back in February of 2019. Dr. Larry J. Young visited the library to talk about the science behind love, specifically in the surprisingly monogamous relationship between prairie voles, and what their genetic makeup may tell us about our own.

Keep in mind that this is an older episode, so the program Dr. Young and I talk about won't actually happen this month, but the content is still super interesting. 

Now on with the show.


Ross: Dr. Young, welcome to the podcast. 

Dr. Larry J. Young: Thank you.

Ross: So, I think about a lot of things when I think about love, but voles aren't one of them. Why voles?

Dr. Young: Well, voles are really interesting little creatures that have taught us a lot about love, believe it or not. They're little hamster-sized rodents that live in the midwestern United States. And, what makes them so special is that, like people, they form life long relationships, especially the prairie voles. These guys, once they mate, something magic happens in their brains so that from then on they stay together; they raise their offspring together; and they usually don't separate. 

Ross: So, they are monogamous rodents.

Dr. Young: We call socially monogamous, which means that they form these bonds, but they are not necessarily always one hundred percent faithful. Sometimes, they slip up. 

Ross: [Laughs] We won't hold that against them, I don't think.

Dr. Young: But that still allows to be able to understand what goes on in the brain to cause animals to form these bonds. Another cool thing about the voles is that there are different species of voles that look almost identical but they don't form bonds at all. They mate. After mating, they split, and the female has her babies by herself, and she raises them by herself. And the male goes off looking for other females. 

So we can actually look in the brains of these two different species that behave very differently and pick apart what's different and identify things that might be important for being able to form that bond. 

Ross: So what makes the prairie vole special? Why are they different than your run-of-the-mill vole? 

Dr. Young: Well, you can answer that two ways. One is why do they have this behavior where they form these bonds, and that has something to do with their environment. Maybe there are predators in the environment, so that if a male decided he didn't want to stick with his female and help protect his offspring and raise those offspring, he may be able to mate with many females and have lots of babies, but if he is not there to protect them, they get eaten. So, the best strategy for him is to stick with his female and he'll have just a few babies, but they are most likely to survive. 

Ross: So it's an evolutionary adaptation.

Dr. Young: It's an evolutionary adaptation, and we understand quite a bit about the brain mechanisms that give rise to that evolutionary adaptation.

Ross: So what is it, specific in their brains then, that allows them to form these bonds with one another?

Dr. Young: Well, there's two molecules in the brain that play important roles here. One is a very special molecule, for humans as well, and that's called oxytocin. Oxytocin is found in all mammals that give birth, and it is the molecule that causes uterus contractions to occur, labor to progress. In fact, if you go to the doctor—a pregnant woman is induced into labor—the doctor gives her oxytocin. That same molecule is released after the baby is born and the baby nurses, it is released from the brain, goes down to the breast, and causes the milk to be ejected. So, it is a quintessential maternal hormone. And, we know that also in all mammals where mothers bond with their babies that oxytocin is released in the brain to cause the mother to bond with the babies.

Now, in prairie voles, that molecule, this signaling system, has been tweaked a little bit, so that mothers cannot only bond with their babies, but adults can bond with each other. And it turns out that the receptor that binds to oxytocin is highly concentrated in a part of the brain that is involved in reward and addiction, and we believe that when adults mate and oxytocin is released, and you also have dopamine being released at the same time, that creates the bond between the partners.

Ross: So you are saying that they essentially become addicted to love.

Dr. Young: Right, there is some amazing parallels between love and addiction. Some of the same brain areas are involved, and the same molecules are involved–so, dopamine for example; opiates are involved in bonding and addiction. And this oxytocin is special because what it does is make social stimuli more salient. In other words, when a mother is nursing her baby, she looks at her baby and that baby is the most special baby in the world to her. The same molecule is released when we make love or when we look into each other's eyes, and it makes our brain really pick up on the cues of the partner. And imagine that those cues, whether that be the face [or] the eyes, they are transmitted into the brain and then oxytocin is released in the brain. Oxytocin is like the grease of the social brain. It helps the flow of that information about your partner through the brain and directs it directly into the reward system to help you make actual neural connections so that the representation of the partner becomes linked into the reward system and that is why your partner is inherently rewarding.

Ross: So, could you artificially stimulate that or inject that? How would that work?

Dr. Young: Yeah, actually, scientists are administering oxytocin all the time to people to try to figure out what does it do. And, it is nowhere near as powerful as the oxytocin that is released when, you know, a couple are together and have a romantic relationship or whatever, but some does get in. One of the more interesting studies was done where they gave men who were in monogamous relationships this intranasal oxytocin or placebo and then they asked them to look at pictures of their wife or other women that college students had ranked to be equally attractive, and what they found was that if men where given the oxytocin, they would rate their partner as more attractive than when they were given placebo. So, it made their partner more attractive, but it did not make other women more attractive. So, it seems that even in humans that oxytocin makes you sort of grow fonder towards your partner and make your partner appear more attractive to you.

Ross: That's incredible.

Dr. Young: Right. So, what you need to do is not to figure out how to take oxytocin but how to stimulate oxytocin release in your partner. 

Ross: [Laughs]

Dr. Young: To make them love you more!

Ross: That sounds like a plan. 

But it goes beyond just marital relationships as well. I know that you had mentioned the affects of oxytocin potentially with relation to the autism spectrum. 

Dr. Young: Right, so as I mentioned before, oxytocin is like the grease of the social brain, what it really does is help the flow of social information throughout the brain making social stimuli more salient. And, of course, that is one of the deficits in autism is that social cues are not any more salient than say trains or chairs, and so we believe that we can tap into this oxytocin system to maybe enhance the salience of social stimuli and maybe that would be useful in making behavioral therapies more effective than they are currently. So, just by studying this little vole and what molecules are involved in forming these bonds, we may be able to improve the quality of life for disorders where there's deficits in the social realm such as autism. 

Ross: So, how close is that to reality? How much research, or field work I guess, have you done?

Dr. Young: Yeah, it is being done all over the world, not just in my lab. I do some of that, but in Australia, I have collaborators, and in Japan—really, all over the world. And we are at a stage where it is definitely not a cure, but we are still investigating and exploring how exactly we might use it [and] when you deliver it, what kind of exposure needs to come after that. So, we are still in the investigation stages, and I think that maybe there will be future developments where there will be other drugs that tap into this oxytocin system so that we are not just getting the same molecule that is produced in our brain, but there are more next generation drugs and I think that's where we might go with this in the future. 

Ross: Because it is definitely more complex than just oxytocin, right? There is a whole bunch of things going on upstairs. 

Dr. Young: Right. You can't just think about a single molecule. You've gotta think about the different brain regions that it's acting in and what those brain regions do. So, it's not just like taking a vitamin. It's not that people with autism don't have enough oxytocin. It's just that we know that if you can give oxytocin and activate these systems you can make social stimuli more salient, and then you've gotta figure out how to deliver social stimuli that may be useful in helping them grow and strengthen their social circuitry.

Ross: So it's not as simple as taking one of those love nasal sprays or anything like that.

Dr. Young: No, it's not. We still have a long way to figure out exactly the best strategy for doing this. 

Ross: That's awesome. Thank you, Dr. Young, for everything. I look forward to seeing you at our program on Sunday, February 10 from 2:00–3:00 p.m., This is Your Brain on Love. 

Dr. Young: Thank you. I'm looking forward to it.

Ross: Thank you.


Additional Links: 
The Chemistry Between Us: Love, Sex, and the Science of Attraction by Dr. Larry J. Young

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