(Never finished this book)
Highlights
- This is a central point of this book—we don’t hate violence. We hate and fear the wrong kind of violence, violence in the wrong context. (Location 126)
- This book explores the biology of violence, aggression, and competition—the behaviors and the impulses behind them, the acts of individuals, groups, and states, and when these are bad or good things. (Location 136)
- In other words, when you think categorically, you have trouble seeing how similar or different two things are. If you pay lots of attention to where boundaries are, you pay less attention to complete pictures. (Location 182)
- Thus, the official intellectual goal of this book is to avoid using categorical buckets when thinking about the biology of some of our most complicated behaviors, (Location 184)
- As noted, we distinguish between hot-blooded and cold-blooded violence. We understand the former more, can see mitigating factors in it—consider the grieving, raging man who kills the killer of his child. And conversely, affectless violence seems horrifying and incomprehensible; (Location 355)
- Which reminds us that we don’t hate aggression; we hate the wrong kind of aggression but love it in the right context. And conversely, in the wrong context our most laudable behaviors are anything but. The motoric features of our behaviors are less important and challenging to understand than the meaning behind our muscles’ actions. (Location 369)
- But on the most proximal level, in this chapter we ask: What happened one second before the behavior that caused it to occur? This puts us in the realm of neurobiology, of understanding the brain that commanded those muscles. (Location 389)
- Consistent with that, the hypothalamus gets massive inputs from limbic layer 2 structures but disproportionately sends projections to layer 1 regions. These are the evolutionarily ancient midbrain and brain stem, which regulate automatic reactions throughout the body. (Location 453)
- All of this is automatic, or “autonomic.” And thus the midbrain and brain-stem regions, along with their projections down the spine and out to the body, are collectively termed the “autonomic nervous system.” (Location 459)
- So the limbic system indirectly regulates autonomic function and hormone release. What does this have to do with behavior? Plenty—because the autonomic and hormonal states of the body feed back to the brain, influencing behavior (typically unconsciously). (Location 482)
- While the hypothalamus dwells at the interface of layers 1 and 2, it is the incredibly interesting frontal cortex that is the interface between layers 2 and 3. (Location 499)
- In different circumstances the frontal cortex and limbic system stimulate or inhibit each other, collaborate and coordinate, or bicker and work at cross-purposes. It really is an honorary member of the limbic system. (Location 506)
- Crucially, the brain region most involved in feeling afraid and anxious is most involved in generating aggression. (Location 575)
- Instead of inevitable fear, we show “prepared learning”—learning to be afraid of snakes and spiders more readily than of pandas or beagles. (Location 618)
- When we stop fearing something, it isn’t because some amygdaloid neurons have lost their excitability. We don’t passively forget that something is scary. We actively learn that it isn’t anymore.fn19 (Location 651)
- In other words, the default state is to trust, and what the amygdala does is learn vigilance and distrust. (Location 666)
- Someone does something lousy and selfish to you in a game, and the extent of insular and amygdaloid activation predicts how much outrage you feel and how much revenge you take. (Location 708)
- Again, there’s a trade-off—increased speed by by-passing the cortex, but decreased accuracy. Thus the input shortcut may prompt you to see the cell phone as a gun. And the output shortcut may prompt you to pull a trigger before you consciously mean to. (Location 729)
- Your heart does roughly the same thing whether you are in a murderous rage or having an orgasm. Again, the opposite of love is not hate, it’s indifference. (Location 749)
- Fear typically increases aggression only in those already prone to it; among the subordinate who lack the option of expressing aggression safely, fear does the opposite. (Location 753)
- Thus, fear and violence are not always connected at the hip. But a connection is likely when the aggression evoked is reactive, frenzied, and flecked with spittle. In a world in which no amygdaloid neuron need be afraid and instead can sit under its vine and fig tree, the world is very likely to be a more peaceful place.fn25 (Location 758)
- the frontal cortex makes you do the harder thing when it’s the right thing to do. (Location 770)
- Once it has decided, the PFC sends orders via projections to the rest of the frontal cortex, sitting just behind it. Those neurons then talk to the “premotor cortex,” sitting just behind it, which then passes it to the “motor cortex,” which talks to your muscles. And a behavior ensues.fn27 (Location 796)