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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”

The population of Asia in 1500 was five times as big as that of Western Europe (284 million compared with 57 million), and the ratio was about the same in 1600. It was a very large market with a network of Asian traders operating between East Africa and India, and from Eastern India to Indonesia. East of the straits of Malacca,
image
trade was dominated by China. Indian ships were not sturdy enough to withstand the typhoons of the China sea, and not adequately armed to deal with pirate activity off the China coast….

The Portuguese displaced Asian traders who had supplied spices to Red Sea and Persian Gulf ports

for onward sale to Venetian, Genoese and Catalan traders. But this was only a fraction, perhaps a quarter, of Asian trade in one group of commodities. In addition there was trade within Asian waters in textiles, porcelain, precious metals, carpets, perfume, jewellery, horses, timber, salt, raw silk, gold, silver, medicinal herbs and many other commodities.

Hence, the spice trade was not the only trading opportunity for the Portuguese, or for the other later European traders (Dutch, British, French and others) who followed. Silk and porcelain played an increased role, and in the seventeenth and eighteenth centuries, cotton textiles and tea became very important. There were possibilities of participating in intra–Asian trade as well. In the 1550s to the 1630s this kind of trade between China and Japan was a particularly profitable source of income for Portugal.

Angus Maddison / OECD

As soon as an Analytic Engine exists, it will necessarily guide the future course of science.

Whenever any result is sought by its aid, the question will arise—By what course of calculation can these results be arrived at by the machine in the shortest time?

Charles Babbage (1864)