The Brain Has 3 Systems for Mating — Combined, They Promote Adultery

Even though adultery is punishable by death in some societies, it still occurs regularly. This tells Dr. Helen Fisher there is probably a genetic predisposition toward cheating on your partner.

Helen Fisher: Everywhere you look in the world people are adulterers, even where you can get your head chopped off for it or stoned. That means that it probably has some biological predisposition. There’s all kinds of cultural reasons that people are adulterers. If you ask a person why they’re adulterers they may say, "Well I get lonely when my partner is out of town; I want to solve a sex problem; I’d like to have more sex; I’d like to get caught and patch up my marriage; I’d like to get caught and end my marriage; I’d like to supplement my marriage." But scientists are beginning to find out some biological predispositions. A predisposition doesn’t mean that you’re necessarily going to be adulterous. I mean, you can have a predisposition to alcohol and give up drinking.

And there’s some things about the brain that seem to predispose some people to adultery. One of them is a set of genes or a gene, we’re not quite sure which, in the vasopressin system. And there was a wonderful study out of Sweden. They studied a gene in the vasopressin among 552 men. Some men had no copies of the gene, some had one copy of the gene and some had two copies of the gene. And the more copies of this gene you had, the less stable your primary relationship was. They were not studying adultery but they were studying the stability of a partnership which can certainly lead to adultery that’s unstable. There’s also some genes in the immune system that seem to play a role in adultery. We tend to be drawn to people who have a different set of genes in this part of the immune system and, in fact, when the data show that when you are with a partner who is very similar to you in this part of the immune system women particularly are more likely to be adulterers and more likely to be adulterers when they’re ovulating, when they’re more likely to get pregnant.

I think we’ve evolved these three distinctly different brain systems for mating and reproduction – sex drive, feelings of intense romantic love and feelings of deep attachment. They’re often connected to each other. You can fall in love with somebody, drives up the dopamine system, triggers the testosterone system and all of a sudden they’re the sexiest person in the whole world. But they’re not always well connected. You can lie in bed at night and feel deep attachment for one person and then swing wildly into feelings of intense romantic love for somebody else and then swing wildly into feeling the sex drive for somebody who you barely ever met.

Which made me wonder whether millions of years ago there was something adaptive about having a partnership with one person and raising your babies and having extra relationships with other people. And it’s actually relatively easy to explain. Let’s dial back a million years. You’ve got a man who’s got a wife, a partnership, and two children. And he occasionally goes over the hill and sleeps with another woman and has two children, extra children, with her. He’s doubled the amount of DNA he has spread into the next generation. Those children will live and pass on whatever it is in him, some of the genetics, some of the brain circuitry to be predisposed to adultery.

But why would a woman be adulterous? A lot of people think that they’re not as adulterous but every time there’s a man sleeping around he’s generally sleeping around with a woman so you’ve got to explain women too. What would a woman have gotten if she’s had a partner a million years ago and two children. She slips over the hill and has sex with another man. Well she’ll get extra goods and resources and extra meat, extra protection. If her husband gets injured and dies one of these extra lovers might come in and help her with her children, even think some of those children are his. It’s an insurance policy. And she may even have an extra child and create more genetic variety in her lineage.

So the bottom line is for millions of years there were some reproductive payoffs not only to forming a pair bond but also to adultery, leaving each one of us with a tremendous drive to fall in love and pair up but also some susceptibility to cheating on the side.

Even though adultery is punishable by death in some societies, it still occurs regularly. This tells Dr. Helen Fisher there is probably a genetic predisposition toward cheating on your partner. Of course not everyone cheats, so it's not necessary for survival, but if we dial back ten thousand years, to a time when resources were more scarce, adultery would have helped genes survive the present generation and be passed onto the next. That gives a clear rational for men's desire to cheat, but what about women? Fisher offers several explanations...

To boost your self-esteem, write about chapters of your life

If you're lacking confidence and feel like you could benefit from an ego boost, try writing your life story.

Personal Growth

In truth, so much of what happens to us in life is random – we are pawns at the mercy of Lady Luck. To take ownership of our experiences and exert a feeling of control over our future, we tell stories about ourselves that weave meaning and continuity into our personal identity.

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Yale scientists restore brain function to 32 clinically dead pigs

Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.

Still from John Stephenson's 1999 rendition of Animal Farm.
Surprising Science
  • Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
  • They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
  • The research raises many ethical questions and puts to the test our current understanding of death.

The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?

But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.

What's dead may never die, it seems

The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.

BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.

The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.

As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.

The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.

"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.

An ethical gray matter

Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.

The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.

Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.

Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?

"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."

One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.

The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.

"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.

It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.

Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?

The dilemma is unprecedented.

Setting new boundaries

Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."

She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.

Ashes of cat named Pikachu to be launched into space

A space memorial company plans to launch the ashes of "Pikachu," a well-loved Tabby, into space.

GoFundMe/Steve Munt
Culture & Religion
  • Steve Munt, Pikachu's owner, created a GoFundMe page to raise money for the mission.
  • If all goes according to plan, Pikachu will be the second cat to enter space, the first being a French feline named Felicette.
  • It might seem frivolous, but the cat-lovers commenting on Munt's GoFundMe page would likely disagree.
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