As the primaries end and the general election race gets underway, a new study provides a timely reminder to both Barack Obama and John McCain: If you hope to inspire your followers, pay careful attention to the imagery of your speeches.

As every successful politician knows, an effective speech can galvanize the public. Charisma, as conveyed on the podium, is an important asset in the ongoing effort to inspire voters and convince them of the wisdom of your ideas.

But why do some addresses galvanize audiences, while others leave listeners cold? An impassioned delivery style is surely one factor, but psychologists Loren J. Naidoo of the City University of New York and Robert G. Lord of the University of Akron have found the specific wording of a speech makes a huge difference.

In a paper published in the June 2008 issue of Leadership Quarterly, the researchers describe an experiment in which two groups of college students listened to different versions of Franklin D. Roosevelt’s first inaugural address. One listened to an actor reading the actual speech, which is full of vivid imagery; the second heard an edited “low-imagery version” in which the poetic passages were replaced by prosaic prose.

FDR spoke of “the withered leaves of industrial enterprise,” a colorful but accurate description of an economy decimated by the Depression. In the low-imagery version, that phrase was changed to “the effects of industrial folly.” A bit later, in an attempt to reassure the public things can and will get better, Roosevelt declared “We are stricken by no plague of locusts.” Version 2.0 replaced that line with “We are faced with no unsolvable problem.”

Naidoo and Lord found the students who listened to the original speech reported higher levels of positive emotional arousal (including interest and excitement), and rated Roosevelt higher in terms of charisma and general leadership qualities.

The researchers note that this important address “helped set the stage for the sweeping reforms that followed,” adding that its effectiveness has “a number of important implications” for today’s political elite.

“For leaders who are in crisis situations, using imagery may help shift followers away from anxiety or despair over the crisis towards en gaging in actions in line with the leader’s vision,” they write.

Or to put it in more vivid terms: Strong, image-based language can act like the flute of the Pied Piper, beckoning people to follow.

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