How We Decide
Jonah Lehrer’s How We Decide
embarks on anecdote-rich journey through the decision-making process, as illuminated by contemporary cognitive science. Written with the clarity and accessibility the popular science genre was meant to bring us, it details our emerging understanding of the complex interplay between various the brain’s various sub-systems.
Lehrer uses as his framework an attempt to demolish the intellect vs. emotion model of the human mind, particularly as found in Plato’s model of the charioteer (intellect) trying to control the wild horses (emotions) under his reins. This informs much of Western thought, from Descartes to Freud to the eternal Spock/McCoy duality. Although he ultimately makes his point, this choice of throughline proves a tad distracting, in that many of his examples seem to reinforce Plato’s conception.
For example, Lehrer shows that we spend way more when we use credit cards instead of cash because our brains react differently to the two types of transactions. Spending cash activates the insula, a sender of unhappy signals, which doesn’t like to expend resources we have in hand. Wise credit card purchasing requires the future-oriented prefrontal cortex to win out over the emotion centers, which overvalue immediate gains. Sounds kinda charioteer vs. horses to me.
The book examines the role dopamine, the brain’s reward chemical, plays in complex learning. When we unconsciously assimilate patterns for later use, we get a jolt of pleasure. When we make a mistake, we get anxiety signals. Thus we store complex information about the world for later use in making split second, instinctive decisions.
That’s why slot machines are so addictive: they give out tons of stimuli, and our brains assume that there’s a pattern to be learned from them. But their outcomes are completely arbitrary (albeit skewed in favor of the house.) The fruitless attempt to subconsciously find their patterns floods the brain with habit-forming dopamine.
Also interesting is the book’s glancing suggestion that unchecked authority may have a similar neurological profile to psychopathology, and its examination of the certainty impulse. Our brains massively reward us, it turns out, for rationalizing away threats to our belief systems. The more extreme the rationalization, the juicier the reward.