Sexual attraction starts with a whiff of signals that gets your motor running. Your nose -- and brain – are behind your gender, sexual orientation, and choice of partner. Kayt Sukel explains how the brain rules when it comes to sex and love.
Dr. Stieg: Today we're talking with Kate Sukel, a science writer and author of several books including Dirty Minds: How Our Brains Influence, Love, Sex and Relationships. So I have to say, Kate, I'm a neurosurgeon and for me I, you know, the brain is the sexiest organ in the body and in fact the brain is a sexual organ. You brought your background in cognitive psychology and engineering psychology together to study the neurobiology of attraction. So let's talk about it. How does our brain influence, loves sex and relationships?
Kate Sukel: Uh, you really can't take it out of the equation whatsoever. I mean, just the same way that it governs every thought, every emotion, every behavior. The brain is right there in the middle of it. I sometimes hesitate to talk about the brain as if it's its own entity. It is kind of directing the scene. It is really sort of pointing us to one person when we really think we should be with another and makes us feel all those feelings and do sometimes risky things. And it's important not to use that as an excuse, but I think really to understand why we often are our own worst enemy when it comes to love and relationships.
Dr. Stieg: Can you describe the basics of what's going on when we become sexually aroused?
Kate Sukel: it really starts often with our noses and of course humans. We think we're a little bit more sophisticated than the sense of smell. After all, we're not rats or dogs. We're not immediately meeting someone and you know, sticking our face, uh, up into their backside. However, we give off a lot of chemo sensory signals. And most of those we're not even aware of. Not only do we give them off, but we picked them up from other people below the level of conscious thought. Our brain somehow processes those and lets us know whether or not somebody is physically attractive, whether that's somebody that we want to have sex with or maybe someone that we might fall in love with. We like to think of ourselves as being very conscious and very deliberate about our choices, but I think all of us before have fallen for someone who wasn't quite what we had in mind and we couldn't really explain the attraction and it might've actually come down to the fact that he just gave off the right smells, smells that we couldn't even necessarily explain or detect, but gave our brain a lot of information about his health status, his genetics, makeup, and also we've been, to a certain extent, his potential status as a father or a partner.
Dr. Stieg: Let's extend this to another topic in terms of the research found regarding the differences between heterosexual and homosexual relationships, is it behavioral and induced? What did you find in your analysis?
Kate Sukel: While certainly the world of neuroscience has gotten away from this idea of being hardwired, I think that if anything is, you know, born this way, it really is a matter of your sexual preferences do come up that way. Patterns of brain activity when it comes to looking at stimuli that are, that are arousing what you find attractive, what you see are the same patterns in a heterosexual male looking at a woman as you do in a homosexual male looking at a man, there is something intrinsic to the brain wiring. That means that people are attracted to one sex over the other.
Dr. Stieg: So is that through functional MRI studies?
Kate Sukel: From functional MRI studies, yes. And also Dick Swaab who's a researcher in the Netherlands, he's also looked at transgender and has found similar things. If you look at differences between male and female brains, you'll find a whole host of different little changes. And in fact when he looked at individuals who were transgendered, he found that they had brains basically that matched the sex that they identified with. So if they were born biologically male, but identified as female, they had very female like brains, even though they happen to have a penis and vice versa. And that's also fascinating, you know, because it shows that there can be this disconnect. It's really sort of opened the door to talk about homosexuality. And transgender issues and have people understand that this isn't a choice. This is something that seems to be written into your code and it's also something that should not be talked about in terms of a mental disease or defect. It's just some kind of biological difference that should be more accepted.
Dr. Stieg: And something at this stage that we still don't have the scientific techniques to really analyze if there is something scientific about it.
Kate Sukel: Well, and that's the hard thing about any of this stuff. We have brain imaging, we have behavioral studies and there's certainly we want the evidence to converge, but we're not at the point now where we really want to be, you know, opening up people's skulls and then mucking about in there. There's some studies that can be done with people who have epilepsy or perhaps some kind of disease that requires deep brain stimulation where you can go in and ask some questions and get a closer look at some brain areas. But those studies are few and far between and they're not always that easy to do. It's hard to understand the nature of love when you have seven minutes to participate in this study in between implanting a deep brain stimulator and closing up somebody's skulls as they can heal properly. A lot of the studies, you know you were talking about before, these researchers are genetically modifying some of these animals and they're looking at how that might change the way the animal behaves in a type of prarie vole that is always been known to be socially monogamous. They find a mate early on and they pretty much stick with them for life. If you start mucking about with these different levels of receptors for neuromodulators like oxytocin and vasopressin, you can actually change in their behavior. You can turn that one very solid, very committed prairie vole into a little Casanova and vice versa. You can take voles that are traditionally more promiscuous and make them that bastion of monogamy. That's not really something we want to be doing with humans. I'm sure there are some people out there listening that would think, I wouldn't mind giving my, my husband a little vasopressin if it meant he stayed home or what have you, but we don't know the far reaching effects. We talk so often in genetics that this is the love gene or this is the monogamy gene or the risk gene or what have you. But really gene's just code for protein and vasopressin actually got its name because it's very important for kidney function and for vasoconstriction in the heart. And you know, so if you up or lower it in certain people, yeah, you might possibly make your man more monogamous, but you may do so at the extent, you know, expense of his kidneys. Maybe that's a worthwhile trade off for you, but probably not for most hospital and universities' institutional review boards.
Dr. Stieg: To where do you see the next most interesting or new developments regarding the sex and brain coming from?
Kate Sukel: We're seeing a lot more work being done on smell. Again, w you know, we sort of think of this as a lower order mammal issue. Dogs smell, rats smell, humans. We've thought that we're kind of above that and yet we're learning in so many different ways how important smell is. In fact, if you look at neurodegenerative disorders like Parkinson's disease, Alzheimer's disease, you'll find that most often one of the first symptoms that comes to light is issues with smell. So obviously we, we may not have the same kind of olfactory setup that many rats or rodents or even primates do, but it seems to play a much more integral role in a lot of cognition than we once thought. And similarly I think it does in terms of understanding why we're attracted to certain people, what it is that that draws us to someone initially and maybe even what later on makes them not attractive at all anymore. I think almost everyone has probably had the experience of feeling madly in love with someone and then kind of waking up one day and thinking, eh, they're just not that great, but what if it is a slight change in smell? What if we are picking up different signals from them at that point? And that makes a difference. What if there are these things that are happening subconsciously for us really do influence how we form these social bonds and how we maintain them over the course of time.
Kate Sukel: What is considered normal love and sexual behaviors? You need to go with the old statistical model of normal and that's of course the normal distribution which looks kind of like a mountain and while we often talk about love and sexual behaviors as if they need to exist in this very, very small contained box, this is what's normal. In fact, they really do run the gamut and I think once people realize that there's nothing wrong with them, they're not unlovable, their brain is really set up for them to love, fail at love, and love again. I think that they do much better. I think overall as humans we put a much, much too much pressure on ourselves about there being a right way to handle love, the right way to be a partner. And of course, like anything else, when you really do map it out, statistically, you'll find out that your mileage may vary and what works for you may not work for someone else. So it pays to pay attention to be cognizant and aware, self-aware, and figure out what's normal for you.
Dr. Stieg: Kate, thanks so much for being with us today and helping us better understand gender and relationship choices.