Hunches & Physiological response

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Slides 30-31

Physiological response  Imagine there are four decks of cards, two of them red and the other two blue. Each card in those four decks either wins or costs you money. Your job is to turn over cards from any of the decks, one at a time, in such a way that maximizes your winnings. What you don’t know is that the red decks are a minefield, and you can really only win by picking cards from the blue decks. The question is, how long will it take you to figure this out?

After we’ve turned over about 50 cards, most of us start to develop a hunch about what’s going on. We don’t know why we prefer the blue decks, but we’re pretty sure, at that point, that they are a better bet.

(CLICK) After turning over about 80 cards, most of us have figured the game out and can explain exactly why the first two decks are such a bad idea.

But the Iowa scientists did something else, and this is where the strange part of the experiment begins. They hooked each gambler up to a polygraph (a lie detector machine) that measured the activity of the sweat glands that all of us have below the skin in the palm of our hands. Most sweat glands respond to temperature, but those in our palms open up in response to stress – which is why we get clammy hands when we are nervous. What the Iowa scientists found out is that gamblers started generating stress responses to the red decks by (CLICK) the tenth card, forty cards before they were able to say that they had a hunch about what was wrong with those two decks. Most importantly, when their palms started sweating their behavior began to change as well: they started favoring the blue decks.

They had a physiological response (triggered by the emotional brain) that affected their behavior before they could make sense of it.