Having followed Jonah Lehrer’s  Seed postings, I looked to the release of his new book.  How We Decide  is a fun and comprehensive survey of Decision Making’s neurologic and cognitive aspects.  http://www.powells.com/blog/?p=4507#more-4507

Book Covers the Landscape: Lehrer’s  How We Decide can seem to be a jumble of entertaining and bewildering fragments, perhaps because the book’s encyclopedic scope overwhelms.  The decision making process might not seem so chaotic, nor undefined, if we understand the sequential process of the sensory message traveling through the brain .

We know that the sensory signals coming in through the brain stem must first run the limbic gauntlet, the

brain’s front-line guards.  The emotions are associated with the amygdala which sits close to the brainstem.  It is not surprising that our emotions can be tied closely to our sense of smell, given their roles as front-line guards.

The incoming signal pattern is compared against a library of friend-or-foe profiles, “caricatures” of the usual suspects, designed for quick recognition for fast response -  as much as some would consider profiling impolitic.

If (a) the sensory signal patterns have not roused the front-line emotional guards, and (b) the brain decides there’s time for a more deliberate analysis, then the patterns are sent up to the rational PFC (prefrontal cortex) tecchie upstairs, which keeps a library of models of cool logic, abstracted from knowledge and experience.

Hopefully, there is a matching model – and a quick “intuitive” response is triggered

The process is sequential , and it’s not as if the brain consciously mulls, “Hmm, I wonder if I should get the PFC (prefrontal cortex) guys  work on this, if not I’ll just push it on my subconscious …”

The brain performs a triage on the incoming signal:  (Case 1) Do the incoming patterns match any known threat models?  If so, then the amygdala shuts the gates and sounds the alarms.   Case (2):  If the patterns are non-threathening, and there’s time,  then the sensory signals are sent up the to the PFC which then checks for a match against its abstracted models.

The brain’s two collections of models: To make decisions the brain has two “libraries” of models learned from its experiences and knowledge: (1) the rational (logical) and, (2) the emotional and instinctual models.     As a defensive mechanism for survival, Fear understandably predominates among the emotions.

We can train ourselves to recognize – i.e., “intuit” – without conscious analysis when a situation matches a model.  The incoming signal must first pass the instinctive and the emotional screens, before the signal is passed on to the rational PFC “techie” on the fifth floor, who might have  ready modules and won’t have to kludge a long analysis .

Two lines of defense : Some studies argue further that we cannot even make decisions without emotions.   You’d see this when the more savvy salespeople instinctually flank their prey:  When the purchase is a major shift for the buyer,  sell first to the fear: create a gap, a pain point. When  the buyer has made that shift, then sell on the product’s features, rationalizing the decision.

And impulse buyer that I am,  my survival instincts know to latch on to the practical features-  to justify later to the wife my latest and greatest gottahavit gizmo.    –