An extremely dense, well organized book, full of interesting facts, but is not targeted at the average reader in my opinion.

I have decide to stop reading this book about 20% in. It reminds me of “Thinking Fast and Slow”, which is another book I never finished. While the content is useful and interesting, it is very dense difficult for me to absorb and retain information from. The only way I managed to remember what I read was by reviewing my notes afterwards. It is worth mentioning that the first time I tried reading Sapiens I also could not finish it, but I absolutely loved it the second time.

Some parts about the frontal cortex were very scientific, rigorous, and provided a lot of new information I wasn’t aware of int he past. However, there were a few very qualitative conversations that dragged on and provided no benefit whatsoever. For example, the whole discussions about testosterone, and how it could make someone more aggressive, or not, and how it could be abused by athletes, or not, just felt very boring and repetitive…

=== Notes ===

  • Ovulation cycles become in sync for mice who live in the same cage as well as college roommates

“The opposite of love is ignorance, not hate”

  • People who love/hate someone else treat them in very similar ways

PNS: Parasympathetic Nervous System

  • Responsible for basic needs like digesting, resting, etc..

SNS: Sympathetic Nervous System

- Responsible for the 4 Fs: Fight, Flight, Feed, Fornicate (i.e. Fuck)

Three layers in the brain:

  • Hypothalamus is between layers 1 and 2

  • Front cortex is between layers 2 and 3

Brain is split into two halves:

- Left system: Analytical

- Right system: Intuitive and creative

Amygdala

  • Responsible for fear, aggression, anxiety, anger, violence, etc…

  • It was later found that Whitman (University of Texas shooter) had a tumor pushing against his amighdala

  • Amygdala kicks in before the prefrontal cortex in identifying people we see (i.e. racial biases)

Prefrontal cortex

  • Crotex (I.e. Front context) comes from the latin term “Tree Bark”

  • Resting metabolic rate in PFC can vary 30 fold between individuals

  • DL-PFC- over-agressive and over-sexual

  • VL_PFC - doesn’t shift behavior based on negative feedback

  • Front cortex makes you do the right thing even when it’s the more difficult thing to do.

- Runaway trolly problem:

- Option 1: Divert trolly to kill one person but save five lives

- Option 2: Push 1 person in front of a moving trolly to save fixes lives

  • DL-PFC responsible for solving this problem

Dopamine

  • Can be generated by just thinking about things like sex, food cars, etc…

- Side note: Made me think about how I personally, am not driven by sex, food, cars, etc…

  • Losing the lottery -> bad luck -> no effects on dopamine

  • Losing a bidding war -> personal loss -> acts as a dopamine inhibitor

Human habitation

  • Humans have a very strong degree of habitation

  • “What was an unexpected pleasure yesterday is what we feel entitled to today, and won’t be enough tomorrow”

Sweat:

  • Humans can tell the difference in smell between sweat that is the result of fear/stress and pheromones