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The Bad News: Trauma Can Be Inherited. The Good News — So Can Resilience
This discovery could lead to a whole new class of drugs for psychiatric disorders.
We tend to understand where our physical traits come from. We may have our mother’s eyes or our father’s chin. But when it comes to personality traits, we tend to think of them as our own. Psychologists go one step farther. They see things like anxiety or depression stemming from personal experiences which shaped us. Some studies however reach back even farther, are in fact passed down from parents or even grandparents.
Neurosis, anxiety, an adventuresome spirit, can these be inherited? That was the question on the minds of two researchers back in 1992. Then molecular biologist and geneticist Moshe Szyf and neurobiologist Michael Meaney, both of Montreal’s McGill University, met after a conference and had a few beers in a nearby bar. They started discussing inheritable traits, and Meaney theorized that certain emotional traits could be passed down through genes inside the brain. Szyf though skeptical was intrigued.
DNA inhabits the nuclei of cells. Since the 1970’s, scientists had wondered what tells each cell to transcribe certain genes and discard others. It was found that molecules in the methyl group earmarked certain genes, tagging them for transcription. Because of the discovery of these methyl groups and their position, each sitting beside a corresponding gene, the field of epigenetics was born. The Greek prefix epi meaning over from. At first, it was thought that epigenetic changes only occurred in the fetal stage of life. Over time, scientists discovered that changes in diet, exposure to certain elements in the environment, and other encounters also changed our DNA.
Artist’s rendition of DNA methylation. By Christoph Bock (Max Planck Institute for Informatics) - Own work, CC BY-SA 3.0
What Prof. Meaney hypothesized was that a parent who experienced a trauma could have certain changes in their brain which might lead to epigenetic changes that were passed on, inhabiting the neurons of their children’s brains or even their grandchildren. That rumination bore an entirely new field, behavioral epigenetics. That means if you had a parent or grandparent who lived through a genocide, war, saw someone murdered, or who suffered a different trauma, say at the hands of an abusive or neglectful parent, you carry traits for the emotional impact in your genes.
A grandfather who was neglected as a child for instance, may have experienced depression, and so passed that predisposition onward. It works in the positive sense too. If your grandfather had loving, nurturing parents, you get a genetic boost in the psychological and behavioral sense. How far does this epigenetic influence go? It’s pretty hard to parse out, even for scientists.
Meaney was able to prove that certain emotional traits were passed down by studying female rats and their pups. He and colleagues gathered data reaching back to the 1950’s. Those baby rats handled by researchers, for as little as five minutes a day, during the first few weeks after birth, were calmer and less stressed than those who were never handled. Meaney and colleagues found this was not due to human handling.
Instead, mother rats were more likely to groom their pups after humans had touched them. They also tended to give them more room for suckling. This extra attention led to better adjusted pups. Meaney showed that the more attention an infant rat received, the lower their stress hormone level in adulthood was. He said, "What we had done up to that point in time was to identify maternal care and its influence on specific genes.” It was after this experiment that Meaney met Szyf.
Syrian refugees. Those who endure dramatic experiences pass epigenetic changes down to their offspring.
The pair conducted an array of experiments. They began by selecting highly attentive mother rats and those who were neglectful. The offspring of neglectful mothers were more anxious and easily startled. Researchers took the offspring of these rats in adulthood and examined their brains, specifically the hippocampus. This is the area that has to do with stress, anxiety, and the formation of memories.
Those who had neglectful mothers had observable changes in the methylation of the genes there. These changes produced more glucocorticoid receptors, which interact with the stress hormone. More of them means a higher sensitivity to stress. Those with diligent mothers did not display such changes.
Next, Meaney and Szyf took a group of pups raised by neglectful mothers. They injected their brains with a drug called trichostatin A. This removes methyl groups. None of the skittishness seen in their mothers was found in this group. Their brains were once again examined, and no epigenetic changes were found. “It was like rebooting a computer,” Szyf said.
In a 2008 study, the pair found that neglectful mother rats had fewer estrogen receptors in their brain. When their female offspring matured, this resulted in fewer estrogen receptors in their brains, which led to neglect of their own young. Meaney and Szyf had discovered what is now called postnatal inheritance, or epigenetic changes from the environment that are written into our DNA, and then passed down to the next generation. These two scientists have published 24 papers on the subject since.
Next, the researchers moved on to human subjects. In a 2008 study, Meaney and Szyf examined the brains of those who committed suicide, and compared them with those who had died for other reasons. Among the suicidal, neural genes in the hippocampus showed excessive methylation. Since their brains were so methylated, researchers concluded that suicidal subjects must have been abused as children. This could be why someone who had neglectful or abusive parents must struggle to overcome the trauma they endured. Methyl groups in their neural genes bind them to feelings of anxiety, hopelessness, malaise, or worry. Of course, due to ethical concerns, examining the brains of living humans is out of the question. Professor Szyf however has located signs of epigenetic methylation in blood samples.
An orphans suffering may affect their genome, long-term.
In one experiment, Szy and researchers from Yale recruited 14 Russian children brought up in an orphanage, and 14 others raised by their parents. Each gave a blood sample which was examined. Orphans had far more methylation than those who were raised by their parents. Areas of the brain important for communication and brain development were most affected.
The study concluded that separation from biological parents causes early stress that effects the person’s genome, long-term. This in turn could explain why adopted children may be more susceptible to damage from harsh parenting styles, on the part of adoptive parents. Study co-author, psychologist Elena Grigorenko wrote, “Parenting adopted children might require much more nurturing care to reverse these changes in genome regulation.”
The most exciting revelation was from a study last year out of New York’s Mount Sinai hospital. 32 holocaust survivors and their children had their genes analyzed. A methylation tag was found in a stress-related gene in parents and children alike. “The gene changes in the children could only be attributed to Holocaust exposure in the parents,” said Rachel Yehuda, lead researchers on the study.
More research must be done to understand the processes involved. How epigenetic changes are passed on from parent to offspring still remains Unknown. Though we may despair that our parents or grandparents trauma lives on in us, Prof. Yehuda says other, related methylation tags may make us more resilient, which could be passed down too.
Some researchers take it a step further. It could be that many or even most of our emotional and psychological tendencies, whether we are intellectual or tactile, communicative or quiet, emotional or stoic, forgetful or possess a perfect memory, might all arise from epigenetic changes passed down from our ancestors. What’s more, this breakthrough could lead to big changes in how we treat psychiatric conditions. Big Pharma and small biotech startups alike are already hunting for compounds, hoping to launch the next generation of drugs for psychiatric disorders, ones that are more effective, with very few, if any, side effects.
To learn more about the holocaust study and it’s implication for mental health click here:
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>
Sexuality dilemmas<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>
Regulating designer babies<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>
It's hard to stop looking back and forth between these faces and the busts they came from.
- A quarantine project gone wild produces the possibly realistic faces of ancient Roman rulers.
- A designer worked with a machine learning app to produce the images.
- It's impossible to know if they're accurate, but they sure look plausible.
How the Roman emperors got faced<a href="https://payload.cargocollective.com/1/6/201108/14127595/2K-ENGLISH-24x36-Educational_v8_WATERMARKED_2000.jpg" ><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQ2NDk2MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyOTUzMzIxMX0.OwHMrgKu4pzu0eCsmOUjybdkTcSlJpL_uWDCF2djRfc/img.jpg?width=980" id="775ca" class="rm-shortcode" data-rm-shortcode-id="436000b6976931b8320313478c624c82" data-rm-shortcode-name="rebelmouse-image" alt="lineup of emperor faces" data-width="1440" data-height="963" /></a>
Credit: Daniel Voshart<p>Voshart's imaginings began with an AI/neural-net program called <a href="https://www.artbreeder.com" target="_blank">Artbreeder</a>. The freemium online app intelligently generates new images from existing ones and can combine multiple images into…well, who knows. It's addictive — people have so far used it to generate nearly 72.7 million images, says the site — and it's easy to see how Voshart fell down the rabbit hole.</p><p>The Roman emperor project began with Voshart feeding Artbreeder images of 800 busts. Obviously, not all busts have weathered the centuries equally. Voshart told <a href="https://www.livescience.com/ai-roman-emperor-portraits.html" target="_blank" rel="noopener noreferrer">Live Science</a>, "There is a rule of thumb in computer programming called 'garbage in garbage out,' and it applies to Artbreeder. A well-lit, well-sculpted bust with little damage and standard face features is going to be quite easy to get a result." Fortunately, there were multiple busts for some of the emperors, and different angles of busts captured in different photographs.</p><p>For the renderings Artbreeder produced, each face required some 15-16 hours of additional input from Voshart, who was left to deduce/guess such details as hair and skin coloring, though in many cases, an individual's features suggested likely pigmentations. Voshart was also aided by written descriptions of some of the rulers.</p><p>There's no way to know for sure how frequently Voshart's guesses hit their marks. It is obviously the case, though, that his interpretations look incredibly plausible when you compare one of his emperors to the sculpture(s) from which it was derived.</p><p>For an in-depth description of Voshart's process, check out his posts on <a href="https://medium.com/@voshart/photoreal-roman-emperor-project-236be7f06c8f" target="_blank">Medium</a> or on his <a href="https://voshart.com/ROMAN-EMPEROR-PROJECT" target="_blank" rel="noopener noreferrer">website</a>.</p><p>It's fascinating to feel like you're face-to-face with these ancient and sometimes notorious figures. Here are two examples, along with some of what we think we know about the men behind the faces.</p>
Caligula<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQ2NDk4Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MzQ1NTE5NX0.LiTmhPQlygl9Fa9lxay8PFPCSqShv4ELxbBRFkOW_qM/img.jpg?width=980" id="7bae0" class="rm-shortcode" data-rm-shortcode-id="ce795c554490fe0a36a8714b86f55b16" data-rm-shortcode-name="rebelmouse-image" data-width="992" data-height="558" />
One of numerous sculptures of Caligula, left
Nero<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQ2NTAwMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NTQ2ODU0NX0.AgYuQZzRQCanqehSI5UeakpxU8fwLagMc_POH7xB3-M/img.jpg?width=980" id="a8825" class="rm-shortcode" data-rm-shortcode-id="9e0593d79c591c97af4bd70f3423885e" data-rm-shortcode-name="rebelmouse-image" data-width="992" data-height="558" />
One of numerous sculptures of Nero, left
To understand ourselves and our place in the universe, "we should have humility but also self-respect," Frank Wilczek writes in a new book.
Debating is cognitively taxing but also important for the health of a democracy—provided it's face-to-face.
- New research at Yale identifies the brain regions that are affected when you're in disagreeable conversations.
- Talking with someone you agree with harmonizes brain regions and is less energetically taxing.
- The research involves face-to-face dialogues, not conversations on social media.
There are two kinds of identity politics. One is good. The other, very bad. | Jonathan Haidt<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="6f0e52833af5d35adab591bb92d79f8e"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/l-_yIhW9Ias?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Unsurprisingly, harmonious synchronization of brain states occurred when volunteers agreed, similar to <a href="https://www.researchgate.net/publication/322764116_Creativity_and_Flow_in_Surgery_Music_and_Cooking_An_Interview_with_Neuroscientist_Charles_Limb" target="_blank">group flow</a>—the coordination of brain waves that hip-hop and jazz musicians (among others) experience when performing together. Coordination exceeds the social, into the neurological. As the team writes, "talking during agreement was characterized by increased activity in a social and attention network including right supramarginal gyrus, bilateral frontal eye-fields, and left frontopolar regions."</p><p>This contrasts with argumentative behavior, in which "the frontoparietal system including bilateral dorsolateral prefrontal cortex, left supramarginal gyrus, angular gyrus, and superior temporal gyrus showed increased activity while talking during disagreement."</p><p>Senior author Joy Hirsch notes that our brain is essentially a social processing network. The evolutionary success of humans is thanks to our ability to coordinate. Dissonance is exhausting. Overall, <a href="https://www.sciencedaily.com/releases/2021/01/210113090938.htm" target="_blank">she says</a>, "it just takes a lot more brain real estate to disagree than to agree," comparing arguments to a symphony orchestra playing different music. </p><p>As the team notes, language, visual, and social systems are all dynamically intertwined inside of our brain. For most of history, yelling at one another in comment sections was impossible. Arguments had to occur the old-fashioned way: while staring at the source of your discontent. </p>
People of the "left-wing" side yell at a Trump supporter during a "Demand Free Speech" rally on Freedom Plaza on July 6, 2019 in Washington, DC.
Credit: Stephanie Keith/Getty Images<p>Leading us to an interesting question: do the same brain regions fire when you're screaming with your fingers on your Facebook feed? Given the lack of visual feedback from the person on the other side of the argument, likely not—as it is unlikely that many people would argue in the same manner when face-to-face with a person on the other side of a debate. We are generally more civil in real life than on a screen.</p><p>The researchers point out that seeing faces causes complex neurological reactions that must be interpreted in real-time. For example, gazing into someone's eyes requires higher-order processing that must be dealt with during the moment. Your brain coordinates to make sense of the words being spoken <em>and</em> pantomimes being witnessed. This combination of verbal and visual processes are "generally associated with high-level cognitive and linguistic functions."</p><p>While arguing is more exhausting, it also sharpens your senses—when a person is present, at least. Debating is a healthy function of society. Arguments force you to consider other viewpoints and potentially come to different conclusions. As with physical exercise, which makes you stronger even though it's energetically taxing, disagreement propels societies forward.</p>In this study, every participant was forced to <em>listen</em> to the other person. As this research was focused on live interactions, it adds to the literature of cognitive processing during live interactions and offers insights into the cognitive tax of anger. Even anger is a net positive when it forces both sides to think through their thoughts and feelings on a matter. As social animals, we need that tension in our lives in order to grow. Yelling into the void of a comments section? Not so helpful. <p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a> and <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a>. His most recent book is</em> "<em><a href="https://www.amazon.com/gp/product/B08KRVMP2M?pf_rd_r=MDJW43337675SZ0X00FH&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee" target="_blank" rel="noopener noreferrer">Hero's Dose: The Case For Psychedelics in Ritual and Therapy</a>."</em></p>
In a joint briefing at the 101st American Meteorological Society Annual Meeting, NASA and NOAA revealed 2020's scorching climate data.