[Editor's note: Plays off catch phrase: "Thought About Saving Darfur?" Saw this paper flier posted at a sandwich place near work in DC last week.]
Republished from SaveDarfur.org.
Get Out of Your Own Way: Studies Show the Value of Not Overthinking a Decision
By ROBERT LEE HOTZ. June 27, 2008; Page A9. Wall Street Journal. View original.
Reprinted from The Wall Street Journal:
Fishing in the stream of consciousness, researchers now can detect our intentions and predict our choices before we are aware of them ourselves. The brain, they have found, appears to make up its mind 10 seconds before we become conscious of a decision — an eternity at the speed of thought.
Their findings challenge conventional notions of choice.
“We think our decisions are conscious,” said neuroscientist John-Dylan Haynes at the Bernstein Center for Computational Neuroscience in Berlin, who is pioneering this research. “But these data show that consciousness is just the tip of the iceberg. This doesn’t rule out free will, but it does make it implausible.”
Through a series of intriguing experiments, scientists in Germany, Norway and the U.S. have analyzed the distinctive cerebral activity that foreshadows our choices. They have tracked telltale waves of change through the cells that orchestrate our memory, language, reason and self-awareness.
In ways we are only beginning to understand, the synapses and neurons in the human nervous system work in concert to perceive the world around them, to learn from their perceptions, to remember important experiences, to plan ahead, and to decide and act on incomplete information. In a rudimentary way, they predetermine our choices.
To probe what happens in the brain during the moments before people sense they’ve reached a decision, Dr. Haynes and his colleagues devised a deceptively simple experiment, reported in April in Nature Neuroscience. They monitored the swift neural currents coursing through the brains of student volunteers as they decided, at their own pace and at random, whether to push a button with their left or right hands.
In all, they tested seven men and seven women from 21 to 30 years old. They recorded neural changes associated with thoughts using a functional magnetic resonance imaging machine and analyzed the results with an experimental pattern-recognition computer program.
While inside the brain scanner, the students watched random letters stream across a screen. Whenever they felt the urge, they pressed a button with their right hand or a button with their left hand. Then they marked down the letter that had been on the screen in the instant they had decided to press the button.
Studying the brain behavior leading up to the moment of conscious decision, the researchers identified signals that let them know when the students had decided to move 10 seconds or so before the students knew it themselves. About 70% of the time, the researchers could also predict which button the students would push.
“It’s quite eerie,” said Dr. Haynes.
A battle of ideas is going on inside your mind.
Reprinted from the Jun 26th 2008 edition of the Economist.
THAT problem solving becomes easier when more minds are put to the task is no more than common sense. But the phenomenon goes further than that. Ask two people to answer a question like “how many windows are there on a London double-decker bus” and average their answers. Their combined guesses will usually be more accurate than if just one person had been asked. Ask a crowd, rather than a pair, and the average is often very close to the truth. The phenomenon was called “the wisdom of crowds” by James Surowiecki, a columnist for the New Yorker who wrote a book about it. Now a pair of psychologists have found an intriguing corollary. They have discovered that two guesses made by the same person at different times are also better than one.
That is strange. Until now, psychologists have assumed that when people make a guess, they make the most accurate guess that they can. Ask them to make a second and it should, by definition, be less accurate. If that were true, averaging the first and second guesses should decrease the accuracy. Yet Edward Vul at the Massachusetts Institute of Technology and Harold Pashler at the University of California, San Diego, have revealed in a study just published in Psychological Science that the average of first and second guesses is indeed better than either guess on its own.
Related content: The wisdom of crowds at the Economist.
Related content: Measuring the Crowd Within: Probabilistic Representations Within Individuals (pdf scientific article)