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Posts tagged with Robert Sapolsky

Robert Sapolsky on the Limbic System (por StanfordUniversity)

  • olfactory bulb takes up 40% of a rodent brain’s projections
  • rhine encephalon — originally viewed as to do with olfaction in all species
  • gathers whatever sense-data pertains to emotions
  • Paul McLean’s triune brain (phylogenetic conservation): hypothalamuspituitarybrainstemmidbrain⊕thyroid⊕pancreas⊕heart (robotic, boring—until it goes wrong) + the limbic system (mostly a mammalian invention: birds, reptiles, fish have less complex limbic systems) ⊕ emotional complexity + cortex (gleaming analytical machine of cognitive expertise — greatly expanded in vertebrates, in mammals, in primates, in us — cortex tied to limbic system, not independent)
  • decisions made under duress
  • think about your own mortality (kicking out “CRH”)
  • so limbic influences cortex and vice versa
  • we are “a fancy species”
  • Odene’s curse — lose the capacity for automatic breathing (you die of sleep deprivation)
  • Antonio DiMasio, Descartes’ Error
  • James Pabes
  • the limbic regions compete to control the hypothalamus (they can shush each other up)
  • edge/network/synaptic distance to the hypothalamus
  • every sense has to go through ge;3 synapses to tell the limbic system anything—except olfaction can hop 1.
  • olfaction takes up only 5% of our brain
  • grey matter (nuclei) vs white matter (axon cables wrapped in myelin)
  • amygdala, hippocampus, septum, mammilary bodies, hypothalamus, thalamus, prefrontal cortex
  • frontal cortex: where am I being touched? which note are you playing? how do I do long division? which limb do I want to move? plus long-term planning, gratification postponement, emotional regulation, impulse control
  • frontal cortex is most recently evolved, relatively largest in humans, not fully mylenated until age 25;size of prefrontal cortex in primates grows as size of typical social group
  • amygdala tells you to be afraid and pings the hippocampus: “Hey, remember to be afraid of this in future”




Robert Sapolsky on Language and schizophrenia

  • importance of FOXP2
    http://upload.wikimedia.org/wikipedia/commons/3/37/Protein_FOXP2_PDB_2a07.png
  • Take away FOXP2 from mice and they talk less complexly.
  • Give mice our human FOXP2 and they talk more.
  • Humans missing FOXP2 can’t do they no talkin be wrongly.
  • Babel → pidgin → creole
  • all creoles have the same grammar
  • …smells like…one inherent human language???
    Correlation
  • ecological factors: rainforest & biodiverse ecosystems tend to produce polytheistic cultures (more linguistic diversity, “more diversity” in many areas)
  • 90% of Earth’s languages will be extinct in not so long.
  • hunter-gatherers have a higher frequency of click languages
  • "Language is how we outsmart plants" —Steven Pinker
  • language is sequential; toolmaking is sequential
  • cooperation — game theory — kin selection — and, lying.
  • Dogs put the lid on their fear pheromones by tucking their tails.
  • A lot of the brain controls facial expressions. (important if you want to lie)
  • Game theory with communication, with semanticity, with syntax, with grammar — all traits of our language — improve outcomes in the game.

Minute 23 — Schizophrenia

  • Sequential thinking is impaired. (Can’t tell a story in an order that will make sense to others.) (Actually that sounds like me.)
  • Loose associations. (Can’t keep straight within one sentence whether “boxer” refers to dog or occupation. Gold caddy vs Cadillac)
  • (So I guess homophones differ among languages and thus schizophrenics of different languages tangent predictably based on their language?)
  • Difficulties with abstraction. (Fact vs parable vs rumour) Always interpret as concrete reality.
  • "Apple, banana, orange. What do these words have in common?" "They’re all multisyllabic words." "OK, that’s true. Anything else?" "Yes. They all have letters with closed loops." Symbolic function of language not working for them.
  • "What’s on your mind?" "My hair." "Can I take your picture?" "I don’t have a picture to give." "Can you write a sentence for me?" "A sentence for me."
  • Belief that they participated in historical events.
  • "What do apples, oranges, and bananas have in common?" "They’re all wired for sound."
  • Hallucinations. The defining feature.
  • Most hallucinations are auditory but we don’t know why.
  • People experience very structured hallucinations, not random ones. But neurologically it looks random. epsilon;
  • In fact papers have been published about the most common hallucinations. Commonest voices, in order: Jesus, Satan, the political leader.
  • The story of a schizophrenic Maasai.
  • After a really abhorrent violation of social convention, they locked her away and she died. Sound familiar? Oh well, I guess she knew what was coming to her and ∴ tacitly rationally agreed to her punishment, right?
  • Nuopharmacology evolving from trying to cure hallucinations to trying to cure disordered thought.
  • Elderly schizophrenics lose the positive symptoms (hallucinations, delusions, loose associations) and the negative symptoms (flat affect and withdrawal) dominate.
  • Schizophrenia sets on in late adolescence/early adulthood—make it to  30 without it, you’re probably safe.
  • Anchored in the frontal cortex.

(por StanfordUniversity)




Another reason for economists to take a close look at inequality, social rank, envy, greed, dreams, social or cultural messages/expectations, and so on as determinants of experienced utility.

Sapolsky’s observation is that human beings engage evolutionary stress hormones in response to purely psychological stimuli. Looking at babboons, who cause each other stress as we do, he finds that lower ranked (submissive) males carry higher amounts of epinephrine (adrenalin) and glucocorticoids than dominant alpha males. (No reports in this documentary on fat-shaming or that ugly females have higher stress.)

So that may be a basis for thinking that social inequality—where a rank and a distance exist—really does mean a lower quality of life for the bottom-rungers, even if they have an absolutely high standard of living. (Sapolsky remarks that in the park he visits, food is so plentiful for the babboons that they only need to work 3 hours a day to survive. So they could be said to have an absolutely high wealth.)

Of course the “right” use of Pareto optimality always took into account the possibility that giving more money to Bill Gates could make me more miserable—but utility is so hard to pin down that a social-optimality conversation can easily be turned by “Well, it’s wrong of you to envy the rich” — casting aside the normative/descriptive distinction.

My first thoughts leap to envy-free solutions of pie-splitting problems (S J Bram, P C Fischburn)

image image image image

but maybe there are some free-lunch alternatives as well. Such as, is there something I’m doing that makes other people feel ashamed or stressed? Some subtle pitches to my voice or subtle movements of my eyes when I’m internally judging someone but trying to not say anything out loud? Why do I care anyway if some hippie wants to be an organic farmer and not get a job? I don’t think I even have a good reason to care; “ideological opposition”. Maybe you can make some arguments sometimes that I should be stressed about the possibility that my government gets overrun by a bunch of irresponsible ideologues and it’s worth the time to debate about it. Fine, but still maybe there are some free lunches in just not socially shaming other people. Just because I have more money doesn’t mean I need to look down on you as less a person. There certainly are narratives that tell that story—"Contribution to society" type narratives or "Hard work" narratives and sometimes even Smart narratives. But I don’t need to embrace those, especially if it’s suboptimal.

 

Minute 28 they show pictures of monkey brains lighting up in the pleasure centre or stress zones.

image

Making me think again of taking an integral of the chemical flows over someone’s life (how to deal with time I don’t know) as some kind of selfish evaluation of the pain/pleasure experienced over the lifetime. The naïvest thing would be to measure dopamine and integrate it up over time, perhaps convolved with a risk preference function, anti-variance or pro-variance preference, and some time preference (either NPV/Ramsey or work hard in youth for a delightful old age). Something more realistic would have to take into account that a full life should experience a variety of emotions and corresponding chemical combinations. When your father dies you don’t want to go on smiling and partying, for example.

  

Minute 48 we get Sapolsky’s interpretation: rank isn’t necessarily it, but rather what rank means in your culture. And our own psychological freedom to decide which hierarchy we think is important. Maybe, RS. Just because I have free will doesn’t make me Herculean, it depends how hard it is to override the bad thoughts with self-affirming thoughts.

Giving rather than receiving. Ask a middle-class parent if s/he is looking forward more to giving something to their child or receiving a present from a friend, partner, or coworker this Christmas? Yet the economics 101 just takes consumption and leisure as life’s desiderata.

So put this together with Daniel Kahneman's supposed finding of an “enough” level (around $45k for Americans I think) above which extra income doesn’t add very much to one’s sense of well-being.

That is, above $45k suponemos que income sea more of a ranking tool or a “You did right” reward. People’s happiness se determine más por the way coworkers and people around them act toward them [do I have to deal with this stressful person today? Does Mr Z laugh at my jokes? Do people look and speak to me as if I’m respectable, smart, admirable, good-looking, sexy, competent, fun, nice—what kind of person am I? Am I good?

image

] y menos por consumption por sí. Their home is comfortable enough, their food is good enough, life is easy enough. Money removes discomfort rather than providing happiness, kind of idea.

Hat tip @ArcAldebaran.




Robert Sapolsky — What Makes Humans Unique

  • it ain’t the genes
  • it ain’t social behaviour
  • it ain’t murder, organised killing, or genocide
  • it ain’t empathy
  • it’s more a matter of how far we take the traits or behaviours exhibited by other animals.