Thursday, October 30, 2008

The undecided brain on WNYC, with Josh!

Tomorrow afternoon at 1:20pm Eastern, Josh Gold and I will be on the Leonard Lopate Show to talk about the neuroscience of being undecided. I'm told there will also be someone from the Pew Center to talk about polling. Tune in - WNYC, 93.9 FM, 820 AM, and online streaming audio.

Josh has very kindly parachuted in on this topic. He works on perceptual decision-making, just one facet of an exciting modern research area, the neural basis of making decisions. He's not quite Sandra, who is off in the South Pacific. But he has a better jump shot!

Tuesday, October 28, 2008

Brain science for the novice

We've been reviewed in Nature Neuroscience by Steven Hyman, provost of the Harvard Medical School and former director of the National Institute of Mental Health. Among other things, he wrote:
"[Welcome To Your Brain is] a remarkably ambitious book that is aimed at sophisticated general readers...a superb general overview of brain science for the non-neurobiologist...Welcome to Your Brain explains a great deal with elegance, clear prose and a welcome sophistication."
The review is a comprehensive summary of what we did, from the point of view of a leading neuroscientist. More is available here.

Monday, October 27, 2008

The undecided brain

In the New York Times I have an op-ed on the neuroscience of being an undecided voter. I wrote it with fellow neuroscientist Josh Gold. Full text, with scientific references:

As we enter the final week of a seemingly endless election campaign, opinion polls continue to identify a substantial fraction of voters who consider themselves "undecided." Although their numbers are dwindling, they could still determine the outcome of the race in some states. Comedians and other commentators have portrayed these people as fools, unable to choose even when confronted with the starkest of contrasts.

Recent research in neuroscience and psychology, however, suggests that most undecided voters may be smarter than you think. They’re not indifferent or unable to make clear comparisons between the candidates. They may be more willing than others to take their time — or else just unaware that they have essentially already made a choice.

Neuroscientists have begun to tease out the brain systems that make some simple decisions. Even when it takes a second or less, decision-making is thought to involve two parts, gathering evidence and committing to a choice. In tasks as simple as deciding whether a shifting pattern of dots is moving to the left or to the right, brain activity in the parietal cortex rises as evidence is gathered, eventually reaching a tipping point of choice - though it is not yet known what brain regions drive the final choice.

Inherent to this kind of process is a trade-off between speed and accuracy. Commit early and you can get on with your life. Take more time and you might make a wiser or more accurate decision. Since a commitment to John McCain or Barack Obama is not required until Nov. 4, for the greatest accuracy, one should gather evidence until that date. So then why aren’t there even more undecided voters? For simpler decisions, after there is enough evidence to reach a decision threshold, the brain tends to ignore further input even when it might improve accuracy. The brain goes ahead and decides, freeing up mental resources to deal with other problems.

This logic suggests that undecided voters might simply require a higher degree of confidence before they commit. Pollsters know this, and so push "uncommitted" voters to state a preference. Although this approach may seem heavy-handed, it gives a fairly accurate reading of a candidate’s support. In psychological studies, people who describe themselves as undecided often reveal a pronounced preference when they are forced to choose. When someone reports being only “moderately sure” of a decision like whether to accept a new job, his eventual choice is all but certain.

Still, the person may not be aware of that internal commitment. In one study, people were asked to play a gambling game in which they could choose cards from several decks, some of which were secretly stacked against them. After losing repeatedly, most subjects began to nervously avoid the less favorable decks but were unable to say why until after much further play. People with damage to the ventromedial prefrontal cortex lack this intuition, and so they take inordinate time to make decisions in general.

Of course, undecided voters aren’t suffering from brain damage, it’s just that their brains may require an especially long amount of time to develop confidence in or awareness of a choice. In these cases, hidden commitments can be queried in creative ways. In a recent study, 33 residents of an Italian town initially told interviewers that they were undecided about their attitude toward a controversial expansion of a nearby American military base. But researchers found that those people’s opinions could be predicted by measuring how quickly they made automatic associations between photographs of the military base with positive or negative words.

If decisions are lurking somewhere in the brains of undecided voters, could brain imaging methods reveal their inclinations? Not yet. Recent research has shown that when undecided voters looked at images of candidates, their brains’ emotional centers were often activated. But this reveals little information about the content of their thoughts. This type of research serves mainly to demonstrate how difficult it is for scientists to physically trace complex concepts like preference.

It is more effective to pose indirect questions. Pollsters can learn which way “undecided” voters lean by using questions they already ask that are likely to correlate with support for either candidate: Who do you think understands your problems better? Are you more concerned about the economy or terrorism? Which candidate has the better temperament? The answers of decided voters could be used to predict the final choice of undecideds.

No matter how deeply they delve into people’s thought processes, however, polls will never be perfect predictors of election results. Like the brain of an undecided voter, the electorate as a whole may lean toward one candidate or another, but until the ballots are cast on Nov. 4, it remains undecided.

Sam Wang, an associate professor of neuroscience at Princeton, is a co-author of “Welcome to Your Brain: Why You Lose Your Car Keys but Never Forget How to Drive and Other Puzzles of Everyday Life.” Joshua Gold is an assistant professor of neuroscience at the University of Pennsylvania.

Friday, October 10, 2008

The neuroscience of being "undecided"

In this year's presidential race, current campaign trends indicate that "undecided" voters make up a similar fraction to the difference in support between Barack Obama and John McCain. How many of them are really undecided? Based on psychology and neuroscience research, maybe not many.

In a recent study (news story), 129 residents of an Italian town were asked about their attitude toward a controversial expansion of a nearby U.S. military base. Researchers found that the opinions of 33 "undecideds" could be predicted a week in advance by a series of questions relevant to the issue. This result raises the possibility that decisions exist in an internal form before people can report them.

The work is reminiscent of neuroscience research by Antonio Damasio and colleagues, who found a way to measure the gap between hunch and recognition. People were asked to play a pretend gambling game in which they could choose cards from several decks. Without the participants' knowledge, some of the decks were stacked against them. After losing repeatedly, they began to choose the more favorable decks but were unable to say why until after much further play.

So even when we claim to be undecided, we may have strong preferences that we cannot report to a questioner. This creates a major problem in interpreting the answers to opinion polls. There may not be many undecided voters out there at all.

(Cross-posted from the Princeton Election Consortium)