The Frontal Cortex

An interesting new study looks at how being able to count your own heartbeats - the most elemental form of biofeedback - correlates with better decision-making, at least when playing the Iowa Gambling Task. Here's Kevin Lewis in the Boston Globe Ideas section:

A team of psychologists in Germany asked people to count their own heartbeats (without taking a pulse) and then asked them to play a computer gambling game, which required choosing repeatedly among four card decks that yielded different returns. People who were more accurate at counting their own heartbeats picked more cards from the decks with better returns. It seems that people who are in touch with feedback from their own body have an easier time learning from positive and negative experiences.

Why would being able to count your heartbeats lead to better performance at a card game? The answer tells us something interesting about the "body loop," and the importance of eavesdropping on those subtle emotions reverberating through our flesh. As William James hypothesized back in 1882, every emotion begins as a series of physiological changes in the body; our metaphysical feelings have a very carnal source. "What kind of an emotion of fear," James wondered, "would be left [after seeing a bear in the woods] if the feeling of quickened heart beats nor of shallow breathing, neither of trembling lips nor of weakened limbs, neither of goose bumps nor of visceral stirrings, were present?" James' answer was simple: without the body there would be no fear. We need the body in order to feel.

Consider the Iowa Gambling Task (IGT), a very clever experimental task pioneered by Antonio Damasio and Antoine Bechara. The task goes like this: a subject--"the player"--is given four decks of cards, two black and two red, and $2,000 of play money. Every card tells the player that they either won money or lost money. The subject is instructed to turn over a card from one of the four decks, and to make as much money as possible.

But the cards aren't distributed at random. The scientists rig the game. Two of the decks are full of high-risk cards. These decks have bigger payouts ($100), but also contain extravagant punishments ($1250). The other two decks, by comparison, are staid and conservative. Although they have smaller payouts ($50), they rarely punish the player. If the gamblers only draw from these two decks, they would come out way ahead.

At first, the card selection process is entirely random. The players have no reason to favor any specific deck, and so they sample from each pile, searching for money-making patterns. On average, people have to turn over about 50 cards before they began to only draw from the profitable decks. It takes about 80 cards before the average experimental subject can explain why they favored those decks. Logic is slow.

But Damasio wasn't interested in logic. He was interested in the body. He attached electrodes to the palms of the subjects and measured the electrical conductance of their skin. In general, higher levels of conductance in the skin signal nervousness and anxiety. (That's why our hands get clammy before a big test.) What Damasio found was that after drawing only 10 cards the hands of the experimental subjects got "nervous" whenever they reached for the negative decks. While the brain had yet to completely understand the game (and wouldn't for another 40 cards), the subject's hands "knew" what deck to draw from. Furthermore, as their hands grew increasingly sweaty, they started drawing more and more frequently from the advantageous decks. The unconscious feelings ricocheting throughout their body preceded their conscious decision. (For more on the body loop, check out Descartes' Error.) The hand led the mind.

This latest study expands on the importance of the body loop. The hand, of course, isn't the only part of the body that's getting nervous - our pulse is also rising, adrenaline is leaking into the bloodstream, etc. Thus, it makes sense that subjects who are more sensitive to all these fleshy emotions would also be better at picking the right cards. They know when they're nervous, and that allows them to take their nervousness into account. The body, in this sense, is a window into the unconscious - it knows more than we know.