How we Decide by Jonah Lehrer (Book Review #1)
https://www.goodreads.com/book/show/3860977-how-we-decide
Should
I buy the shirt, or the shoes? A ticket home for spring break, or a trip with
the roommates? Going on the late-night restaurant excursion or catching up on
sleep? If there’s one thing I’ve learned in college, it’s that decisions are an
integral part of nearly everything we do. If you’ve ever wondered how the
process works, how to make better decisions and why, this book is a good layman’s
resource!
Any time we’re faced with two or more
conflicting choices, our brain filters massive amounts of information and offers
an emotional response, largely based on release of the chemical dopamine.
Dopamine is released in response to stimuli, generating patterns (often
cause-effect) based on data collected by the anterior cingulate cortex (ACC). Any
time we face a situation which relates to past experiences, our brain projects
a response derived from this information that yields the best possible result.
The brain is constantly weighing excitation of the NAcc (nucleus accumens)
against the insula, ultimately presenting a consensus response even if the
cost-benefit analysis is very close. This is an incredibly useful process,
honed through millions of years of evolution, and operates extremely efficiently.
In a case study involving four decks of cards, with corresponding rewards (two
of which had smaller rewards, but a much better average return), people’s “gut”
reaction (their physical stimuli, such as perspiration or increased heart rate)
indicated pattern recognition some four times faster than the rational brain
could produce. While such studies seem to indicate the necessity of “following
our inclinations,” they fail to capture a few key blind spots: truly random
processes, simple decisions, and processes that are unprecedented in prior
experience.
To
illustrate this, we look at patients whose dopamine activity is increased—patients
with Parkinson’s disease, for example, who take drugs to increase the activity
of their current dopamine chemicals to compensate for extensive loss in
quantity. In such subjects, the propensity to gamble is wildly increased,
because dopamine rewards unpredicted success. A slot machine, for example, becomes
intoxicatingly fascinating for its anomalous payouts, which represent a mystery
that refuses to be solved. Truly random events, consequently, are best left to
the rational brain.
Simple
decisions testify to the utility of the pre-frontal cortex (PFC), found in the
frontal lobe and far more developed in higher primates than any other animals
in the world. The PFC permits that a wide variety of data can be processed,
repackaged, and applied to novel situations. This is a relatively new
(evolutionarily speaking) but exceptionally useful process, which permits
development of forward looking counterfactuals (how will this affect me in the
future?). An unfortunate limitation is the human working memory, which can only
process between 5 and 9 pieces of disparate data at any given time. Thus, the
PFC is more efficient than emotions
at differentiating between a couple pieces of data (which type of oatmeal
should I buy), and far less efficient
in very complicated situations (should I ask the girl out? Do I want to take
job A or job B?). It is also extremely useful in novel situations, where past
experience is irrelevant (piloting a crashing airplane before flight
simulators).
So how
should we make decisions? The best uniform advice is to trust your gut in very
important decisions, like buying a car or choosing a wife. It’s important that
you let your rational brain take in the convoluted information (read reviews,
learn about features, go on a serious number of dates), but there should be a
period of incubation or distraction of the rational brain while the emotional half
churns through information. Consumers who were given too much data before making a car purchase selected the
(objectively) best vehicle only 25% of the time, but when they were distracted
by a memory game in-between, their success rate was well over 60%. In simple
decisions, like buying groceries or having another cup of coffee, the rational
brain is your tool of choice. When in doubt, metacognition (thinking about
thinking) can save us from impulsive decisions, or allow us to give ourselves
the space to let our emotional supercomputer take the lead.
Hope this helps! Questions, corrections, and comments are
encouraged!
Sean
