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| Link | Quote | Stars | Tags | Author |
| 277a77d | Various studies, predominantly by Roy Baumeister of Florida State University, show that when the frontal cortex labors hard on some cognitive task, immediately afterward individuals are more aggressive and less empathic, charitable, and honest. Metaphorically, the frontal cortex says, "Screw it. I'm tired and don't feel like thinking about my fellow human." | Robert M. Sapolsky | ||
| 4737d9d | When you get the news that everyone else disagrees with you, there is also activation of the (emotional) vmPFC, the anterior cingulate cortex, and the nucleus accumbens. This is a network mobilized during reinforcement learning, where you learn to modify your behavior when there is a mismatch between what you expected to happen and what actually did. Find out that everyone disagrees with you and this network activates. What is it basically .. | Robert M. Sapolsky | ||
| b7f7e4d | Josh Greene and Jonathan Cohen of Princeton wrote an extremely clearheaded piece on this, "For the Law, Neuroscience Changes Nothing and Everything." Where neuroscience and the rest of biology change nothing is in the continued need to protect the endangered from the dangerous.30" | Robert M. Sapolsky | ||
| 3f701e2 | How's this for a display of human kin selection: Subjects were given a scenario of a bus hurtling toward a human and a nondescript dog, and they could only save one. Whom would they pick? It depended on degree of relatedness, as one progressed from sibling (1 percent chose the dog over the sibling) to grandparent (2 percent) to distant cousin (16 percent) to foreigner (26 percent).55 | Robert M. Sapolsky | ||
| a711c61 | Let's see what "multifactorial" means in a practical sense. Consider someone with frequent depression who is visiting a friend today, pouring her heart out about her problems. How much could you have predicted the global depression and today's behavior by knowing about her biology? Suppose "knowing about her biology" consisted only of knowing what version of the serotonin transporter gene she has. How much predictive power does that give yo.. | Robert M. Sapolsky | ||
| e955941 | Irrational optimism can be great; it's why only about 15 percent instead of 99 percent of humans get clinically depressed. | Robert M. Sapolsky | ||
| c548068 | Since it morphed from "battle fatigue" or "shell shock" into a formal psychiatric illness, combat PTSD has been framed as a result of the sheer terror of being under attack, of someone trying to kill you and those around you. As we've seen, it is an illness where fear conditioning is overgeneralized and pathological, an amygdala grown large, hyperreactive, and convinced that you are never safe. But consider drone pilots--soldiers who sit in.. | Robert M. Sapolsky | ||
| 69cbaad | But consider a paper published in Science in 2008.1 The authors examined the relationship between math scores and sexual equality in forty countries (based on economic, educational, and political indices of gender equality; the worst was Turkey, the United States was middling, and, naturally, the Scandinavians were tops). Lo and behold, the more gender equal the country, the less of a discrepancy in math scores. By the time you get to the S.. | Robert M. Sapolsky | ||
| f28e3de | Edward Tylor, a distinguished nineteenth-century cultural anthropologist. For him culture is "that complex whole which includes knowledge, belief, art, morals, law, custom, and any other capabilities and habits acquired by man [sic] as a member of society." | Robert M. Sapolsky | ||
| 9d025a8 | Thus, we tend to think of Us as noble, loyal, and composed of distinctive individuals whose failings are due to circumstance. Thems, in contrast, seem disgusting, ridiculous, simple, homogeneous, undifferentiated, and interchangeable. | Robert M. Sapolsky | ||
| 85e6bfd | There is often an inverse relationship between levels of intragroup and intergroup aggression. In other words, groups with highly hostile interactions with neighbors tend to have minimal internal conflict. Or, to spin this another way, groups with high levels of internal conflict are too distracted to focus hostility on the Others. | Robert M. Sapolsky | ||
| cbef8f0 | if some octopus moved in next door, I would feel hostile superiority because I have a spine and it didn't, but that animosity might melt into a sense of kinship when I discovered that the octopus, like me, loved playing Twister as a kid. | Robert M. Sapolsky | ||
| 8997d98 | Expose subjects to evidence of someone else in pain. If their heart rate increases a lot (a peripheral indicator of anxious, amygdaloid arousal), they are unlikely to act prosocially in the situation. The prosocial ones are those whose heart rates decrease; they can hear the sound of someone else's need instead of the distressed pounding in their own chests. | Robert M. Sapolsky | ||
| f158185 | math performance in Asian American women, built around the stereotypes of Asians being good at math, and women not. Half the subjects were primed to think of themselves as Asian before a math test; their scores improved. Half were primed about gender; scores declined. Moreover, levels of activity in cortical regions involved in math skills changed in parallel. | Robert M. Sapolsky | ||
| 76900f1 | The depths of human conformity and obedience are shown by the speed with which they occur--it takes less than 200 milliseconds for your brain to register that the group has picked a different answer from yours, and less than 380 milliseconds for a profile of activation that predicts changing your opinion. Our brains are biased to get along by going along in less than a second. | Robert M. Sapolsky | ||
| 75cdf07 | Roughly half a million people died in the Roman Colosseum to supply audiences of tens of thousands the pleasure of watching captives raped, dismembered, tortured, eaten by animals. | Robert M. Sapolsky | ||
| 3b608e8 | The sympathetic nervous system (SNS) mediates the body's response to arousing circumstances, for example, producing the famed "fight or flight" stress response. To use the feeble joke told to first-year medical students, the SNS mediates the "four Fs--fear, fight, flight, and sex." Particular midbrain/brain-stem nuclei send long SNS projections down the spine and on to outposts throughout the body, where the axon terminals release the neuro.. | Robert M. Sapolsky | ||
| 42d26ab | As emphasized in chapter 10, people become more prosocial when reputation rides on it, and personality profiles also show that highly charitable people tend to be particularly dependent on external approval. Two of the studies just cited that showed dopaminergic activation when people were being charitable came with a catch. Subjects were given money and, while in a brain scanner, decided whether to keep the money or donate. Being charitabl.. | Robert M. Sapolsky | ||
| 663882a | Thus, particularly important is a 2011 study that used transcranial magnetic stimulation techniques to temporarily inactivate the vmPFC; subjects became less likely to change their answer to conform. | Robert M. Sapolsky | ||
| 5b39a9d | Feeling someone else's pain can be more effective for learning than just knowing that they're in pain. At its core the ACC is about self-interest, with caring about that other person in pain as an add-on. | Robert M. Sapolsky | ||
| e6b2cd4 | Young humans are like chimps--six-year-olds not only prefer to be with kids like themselves (by whatever criteria) but readily say so. It isn't until around age ten that kids learn that some feelings and thoughts about Thems are expressed only at home, that communication about Us/Them is charged and contextual.60 | Robert M. Sapolsky | ||
| c850009 | religious wars, which are, to cite a quote generally attributed to Napoleon, "people killing each other over who has the better imaginary friend," | Robert M. Sapolsky | ||
| bbc2eeb | Norenzayan distinguishes between private and communal religiosity in surveying support for suicide bombers among Palestinians.17 In a refutation of "Islam = terrorism" idiocy, people's personal religiosity (as assessed by how often they prayed) didn't predict support for terrorism. However, frequently attending services at a mosque did. The author then polled Indian Hindus, Russian Orthodox adherents, Israeli Jews, Indonesian Muslims, Briti.. | Robert M. Sapolsky | ||
| 03126ff | This system can indicate that this mouse is John Smith. How does it also tell that he's your never-before-encountered brother? The closer the relative, the more similar their cluster of MHC genes and the more similar their olfactory signature. Olfactory neurons in a mouse contain receptors that respond most strongly to the mouse's own MHC protein. Thus, if the receptor is maximally stimulated, it means the mouse is sniffing its armpit. If n.. | Robert M. Sapolsky | ||
| dec7662 | glucocorticoids in | Robert M. Sapolsky | ||
| ca514cc | A powerful example of this is seen in the first war of Indian independence, also known as the Sepoy Mutiny, of 1857. Indian soldiers--sepoys--serving in the British East India Company's army rebelled when it became known that the bullets they were issued were greased in either tallow, derived from cows, or lard, from pigs--major offenses to the Hindu and Muslim soldiers, respectively. Mind you, this was not the British colonial overlords do.. | Robert M. Sapolsky | ||
| b2375bc | Kids learn dichotomies in the absence of any ill intent. When a kindergarten teacher says, "Good morning, boys and girls," the kids are being taught that dividing the world that way is more meaningful than saying, "Good morning, those of you who have lost a tooth and those of you who haven't yet." | Robert M. Sapolsky | ||
| 3f128bd | Stress can be bad for you. We no longer die of smallpox or the plague and instead die of stress-related diseases of lifestyle, like heart disease or diabetes, where damage slowly accumulates over time. It is understood how stress can cause or worsen disease or make you more vulnerable to other risk factors. Much of this is even understood on the molecular level. Stress can even cause your immune system to abnormally target hair follicles, c.. | Robert M. Sapolsky | ||
| cb849c5 | By ages four through six, kids in cultures from around the world respond negatively when they are the ones being shortchanged. It isn't until ages eight through ten that kids respond negatively to someone else being treated unfairly. | Robert M. Sapolsky | ||
| 32858f7 | I once received a lesson in kids' private world of rule making from my then-four-year-old son. We had gone to a public bathroom together; we stood side by side at two urinals, and I finished a bit earlier than he did. "I wish we had finished at the same time," he said. Why? "We get more points that way." | Robert M. Sapolsky | ||
| a98802e | Level 1: Should I Eat the Cookie? Preconventional Reasoning Stage 1. It depends. How likely am I to get punished? Being punished is unpleasant. Aggression typically peaks around ages two through four, after which kids are reined in by adults' punishment ("Go sit in the corner") and peers (i.e., being ostracized). Stage 2. It depends. If I refrain, will I get rewarded? Being rewarded is nice. Both stages are ego-oriented--obedience and self-.. | Robert M. Sapolsky | ||
| e533260 | THE AMYGDALAfn8 IS the archetypal limbic structure, sitting under the cortex in the temporal lobe. It is central to mediating aggression, along with other behaviors that tell us tons about aggression. | Robert M. Sapolsky | ||
| 0a247a0 | A recent study adds an important twist to this story. There are the kids with problems with impulse control--"I'm absolutely going to hold out for two marshmallow"--who then instantly eat that first one. That profile is a statistical predictor of adult violent crime. In contrast, there are kids with steep time-discounting curves--"Wait fifteen minutes for two marshmallows when I can have one right now? What kind of fool waits fifteen minute.. | Robert M. Sapolsky | ||
| bafc1bf | A remarkably consistent finding, starting with elementary school students, is that males are better at math than females. While the difference is minor when it comes to considering average scores, there is a huge difference when it comes to math stars at the upper extreme of the distribution. For example, in 1983, for every girl scoring in the highest percentile on the math SAT, there were eleven boys. Why the difference? There have always .. | Robert M. Sapolsky | ||
| 85c63cd | There's an additional depressing reason why stress fosters aggression--because it reduces stress. Shock a rat and its glucocorticoid levels and blood pressure rise; with enough shocks, it's at risk for a "stress" ulcer. Various things can buffer the rat during shocks--running on a running wheel, eating, gnawing on wood in frustration. But a particularly effective buffer is for the rat to bite another rat. Stress-induced (aka frustration-ind.. | Robert M. Sapolsky | ||
| 6b2e265 | Culture leaves long-lasting residues--Shiites and Sunnis slaughter each other over a succession issue fourteen centuries old; across thirty-three countries population density in the year 1500 significantly predicts how authoritarian the government was in 2000; over the course of millennia, earlier adoption of the hoe over the plow predicts gender equality today. | Robert M. Sapolsky | ||
| d873156 | games. A summary: Exposing children to a violent TV or film clip increases their odds of aggression soon after.41 Interestingly, the effect is stronger in girls (amid their having lower overall levels of aggression). Effects are stronger when kids are younger or when the violence is more realistic and/or is presented as heroic. Such exposure can make kids more accepting of aggression--in one study, watching violent music videos increased ad.. | Robert M. Sapolsky | ||
| 41782eb | Oxytocin and vasopressin facilitate mother-infant bond formation and monogamous pair-bonding, decrease anxiety and stress, enhance trust and social affiliation, and make people more cooperative and generous. But this comes with a huge caveat--these hormones increase prosociality only toward an Us. When dealing with Thems, they make us more ethnocentric and xenophobic. Oxytocin is not a universal luv hormone. It's a parochial one. | Robert M. Sapolsky | ||
| b844a5b | Two Last Thoughts If you had to boil this book down to a single phrase, it would be "It's complicated." Nothing seems to cause anything; instead everything just modulates something else. Scientists keep saying, "We used to think X, but now we realize that ..." Fixing one thing often messes up ten more, as the law of unintended consequences reigns. On any big, important issue it seems like 51 percent of the scientific studies conclude one th.. | Robert M. Sapolsky | ||
| aa9ab84 | Remarkably, studies have examined brains of transgender individuals, concentrating on brain regions that, on the average, differ in size between men and women. And consistently, regardless of the desired direction of the sex change and, in fact, regardless of whether the person had undergone a sex change yet, the dimorphic brain regions in transgender individuals resembled the sex of the person they had always felt themselves to be, not the.. | Robert M. Sapolsky | ||
| c36fa3e | Here's an imaginary twin pair that would be God's gift to behavior geneticists--identical twin boys separated at birth. One, Shmuel, is raised as an Orthodox Jew in the Amazon; the other, Wolfie, is raised as a Nazi in the Sahara. Reunite them as adults and see if they do similar quirky things like, say, flushing the toilet before using it. Flabbergastingly, one twin pair came close to that. They were born in 1933 in Trinidad to a German Ca.. | Robert M. Sapolsky | ||
| ecd1c30 | Perhaps fifty years since we learned that reading problems of a type that we now call dyslexia aren't due to laziness but instead involve microscopic cortical malformations. | Robert M. Sapolsky | ||
| a1e42f4 | Most child behavioral development research is implicitly stage oriented, concerning: (a) the sequence with which stages emerge; (b) how experience influences the speed and surety with which that sequential tape of maturation unreels; and (c) how this helps create the adult a child ultimately becomes. | Robert M. Sapolsky | ||
| 14e73f8 | No brain region is an island, and the formation of circuits connecting far-flung brain regions is crucial--how else can the frontal cortex use its few myelinated neurons to talk to neurons in the brain's subbasement to make you toilet trained?2 As we saw, mammalian fetuses overproduce neurons and synapses; ineffective or unessential synapses and neurons are pruned, producing leaner, meaner, more efficient circuitry. To reiterate a theme fro.. | Robert M. Sapolsky |