With the 2012 presidential election looming on the horizon in November, consider these two crucial questions: Who looks more competent, Barack Obama or Mitt Romney? Who has the deepest and most resonant voice? Maybe your answer is, “Who cares? I vote for candidates based on their policies and positions, not on how they look and sound!” If so, that very likely is your rational brain justifying an earlier choice that your emotional brain made based on these seemingly shallow criteria.

Before the election, I urge you to read Leonard Mlodinow's new book, Subliminal: How Your Unconscious Mind Rules Your Behavior (Pantheon). You will gain such insights as that higher-pitched voices are judged by subjects as more nervous, less truthful and less empathetic than speakers with lower-pitched voices and that speaking a little faster and louder, with fewer pauses and greater variation in volume, leads people to judge someone to be energetic, intelligent and knowledgeable. Looks matter even more. One study presented subjects with campaign flyers featuring black-and-white photographs of models posing as Democrats or Republicans in fictional congressional races; half looked able and competent, whereas the other half did not, as rated by volunteers before the experiment. The flyers included the candidate's name, party affiliation, education, occupation, political experience and three position statements. To control for party preference, half the subjects were shown the more suitable-looking candidate as a Democrat, and the other half saw him as a Republican. Results: 59 percent of the vote went to the candidate with the more capable appearance regardless of other qualifications. A similar study in a mock election resulted in a 12-percentage-point advantage for the more authoritative-looking politician.

To test these effects in real elections, Princeton University psychologist Alexander Todorov and his colleagues had volunteers rate for “competence” black-and-white head shots of all the candidates in 600 contests for the U.S. House of Representatives and 95 races for the Senate from 2000, 2002 and 2004. Results: candidates rated as more competent won 67 percent of the House races and 72 percent of the Senate ones. In a follow-up study published in 2007 the psychologists conducted the face-evaluation process before the 2006 elections, predicting the winners in 72 percent of Senate runs and 69 percent of gubernatorial competitions based on the candidates' appearances alone.

These data—and others—confirm what was perceived the night of September 26, 1960, during the first televised presidential debate between John F. Kennedy and Richard M. Nixon. Well rested and tan from campaigning in California, Kennedy was radiant, like an “athlete come to receive his wreath of laurel,” journalist Howard K. Smith noted. In contrast, Nixon had been campaigning right up to the debate and had been hospitalized for a knee infection that had left him with a 102-degree fever and looking pale and haggard, worsened by his notoriously heavy five o'clock shadow. Seventy million people watched the event. Millions more listened on the radio. According to a study published in the trade journal Broadcasting, those who saw the debate thought Kennedy won, whereas those who heard it gave Nixon the nod. For example, when New York Herald Tribune writer Earl Mazo first observed reactions to the debate at a conference, he observed, “Nixon was best on radio simply because his deep, resonant voice conveyed more conviction, command, and determination than Kennedy's higher-pitched voice and his Boston-Harvard accent. But on television, Kennedy looked sharper, more in control, more firm.” These conclusions were replicated in a 2003 study in which subjects who viewed the debate were more likely to think Kennedy won than those who listened to it.

Why are we so influenced by such apparently trivial characteristics as voice and looks? In our evolutionary past they served as proxies for health, vigor and overall fitness (in both the physical and evolutionary sense). Such cognitive shortcuts remain necessary today because in a world abuzz with information overload, it isn't possible to rationally analyze all incoming data. So, on Election Day, try to override your predictably irrational propensity to succumb to these influences and engage your rational brain to vote the issues and not the person.

SCIENTIFIC AMERICAN ONLINE

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